| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/kernel/sys.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| */ |
| |
| #include <linux/export.h> |
| #include <linux/mm.h> |
| #include <linux/mm_inline.h> |
| #include <linux/utsname.h> |
| #include <linux/mman.h> |
| #include <linux/reboot.h> |
| #include <linux/prctl.h> |
| #include <linux/highuid.h> |
| #include <linux/fs.h> |
| #include <linux/kmod.h> |
| #include <linux/perf_event.h> |
| #include <linux/resource.h> |
| #include <linux/kernel.h> |
| #include <linux/workqueue.h> |
| #include <linux/capability.h> |
| #include <linux/device.h> |
| #include <linux/key.h> |
| #include <linux/times.h> |
| #include <linux/posix-timers.h> |
| #include <linux/security.h> |
| #include <linux/suspend.h> |
| #include <linux/tty.h> |
| #include <linux/signal.h> |
| #include <linux/cn_proc.h> |
| #include <linux/getcpu.h> |
| #include <linux/task_io_accounting_ops.h> |
| #include <linux/seccomp.h> |
| #include <linux/cpu.h> |
| #include <linux/personality.h> |
| #include <linux/ptrace.h> |
| #include <linux/fs_struct.h> |
| #include <linux/file.h> |
| #include <linux/mount.h> |
| #include <linux/gfp.h> |
| #include <linux/syscore_ops.h> |
| #include <linux/version.h> |
| #include <linux/ctype.h> |
| #include <linux/syscall_user_dispatch.h> |
| |
| #include <linux/compat.h> |
| #include <linux/syscalls.h> |
| #include <linux/kprobes.h> |
| #include <linux/user_namespace.h> |
| #include <linux/time_namespace.h> |
| #include <linux/binfmts.h> |
| |
| #include <linux/sched.h> |
| #include <linux/sched/autogroup.h> |
| #include <linux/sched/loadavg.h> |
| #include <linux/sched/stat.h> |
| #include <linux/sched/mm.h> |
| #include <linux/sched/coredump.h> |
| #include <linux/sched/task.h> |
| #include <linux/sched/cputime.h> |
| #include <linux/rcupdate.h> |
| #include <linux/uidgid.h> |
| #include <linux/cred.h> |
| |
| #include <linux/nospec.h> |
| |
| #include <linux/kmsg_dump.h> |
| /* Move somewhere else to avoid recompiling? */ |
| #include <generated/utsrelease.h> |
| |
| #include <linux/uaccess.h> |
| #include <asm/io.h> |
| #include <asm/unistd.h> |
| |
| #include "uid16.h" |
| |
| #include <trace/hooks/sys.h> |
| |
| #ifndef SET_UNALIGN_CTL |
| # define SET_UNALIGN_CTL(a, b) (-EINVAL) |
| #endif |
| #ifndef GET_UNALIGN_CTL |
| # define GET_UNALIGN_CTL(a, b) (-EINVAL) |
| #endif |
| #ifndef SET_FPEMU_CTL |
| # define SET_FPEMU_CTL(a, b) (-EINVAL) |
| #endif |
| #ifndef GET_FPEMU_CTL |
| # define GET_FPEMU_CTL(a, b) (-EINVAL) |
| #endif |
| #ifndef SET_FPEXC_CTL |
| # define SET_FPEXC_CTL(a, b) (-EINVAL) |
| #endif |
| #ifndef GET_FPEXC_CTL |
| # define GET_FPEXC_CTL(a, b) (-EINVAL) |
| #endif |
| #ifndef GET_ENDIAN |
| # define GET_ENDIAN(a, b) (-EINVAL) |
| #endif |
| #ifndef SET_ENDIAN |
| # define SET_ENDIAN(a, b) (-EINVAL) |
| #endif |
| #ifndef GET_TSC_CTL |
| # define GET_TSC_CTL(a) (-EINVAL) |
| #endif |
| #ifndef SET_TSC_CTL |
| # define SET_TSC_CTL(a) (-EINVAL) |
| #endif |
| #ifndef GET_FP_MODE |
| # define GET_FP_MODE(a) (-EINVAL) |
| #endif |
| #ifndef SET_FP_MODE |
| # define SET_FP_MODE(a,b) (-EINVAL) |
| #endif |
| #ifndef SVE_SET_VL |
| # define SVE_SET_VL(a) (-EINVAL) |
| #endif |
| #ifndef SVE_GET_VL |
| # define SVE_GET_VL() (-EINVAL) |
| #endif |
| #ifndef PAC_RESET_KEYS |
| # define PAC_RESET_KEYS(a, b) (-EINVAL) |
| #endif |
| #ifndef PAC_SET_ENABLED_KEYS |
| # define PAC_SET_ENABLED_KEYS(a, b, c) (-EINVAL) |
| #endif |
| #ifndef PAC_GET_ENABLED_KEYS |
| # define PAC_GET_ENABLED_KEYS(a) (-EINVAL) |
| #endif |
| #ifndef SET_TAGGED_ADDR_CTRL |
| # define SET_TAGGED_ADDR_CTRL(a) (-EINVAL) |
| #endif |
| #ifndef GET_TAGGED_ADDR_CTRL |
| # define GET_TAGGED_ADDR_CTRL() (-EINVAL) |
| #endif |
| |
| /* |
| * this is where the system-wide overflow UID and GID are defined, for |
| * architectures that now have 32-bit UID/GID but didn't in the past |
| */ |
| |
| int overflowuid = DEFAULT_OVERFLOWUID; |
| int overflowgid = DEFAULT_OVERFLOWGID; |
| |
| EXPORT_SYMBOL(overflowuid); |
| EXPORT_SYMBOL(overflowgid); |
| |
| /* |
| * the same as above, but for filesystems which can only store a 16-bit |
| * UID and GID. as such, this is needed on all architectures |
| */ |
| |
| int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; |
| int fs_overflowgid = DEFAULT_FS_OVERFLOWGID; |
| |
| EXPORT_SYMBOL(fs_overflowuid); |
| EXPORT_SYMBOL(fs_overflowgid); |
| |
| /* |
| * Returns true if current's euid is same as p's uid or euid, |
| * or has CAP_SYS_NICE to p's user_ns. |
| * |
| * Called with rcu_read_lock, creds are safe |
| */ |
| static bool set_one_prio_perm(struct task_struct *p) |
| { |
| const struct cred *cred = current_cred(), *pcred = __task_cred(p); |
| |
| if (uid_eq(pcred->uid, cred->euid) || |
| uid_eq(pcred->euid, cred->euid)) |
| return true; |
| if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) |
| return true; |
| return false; |
| } |
| |
| /* |
| * set the priority of a task |
| * - the caller must hold the RCU read lock |
| */ |
| static int set_one_prio(struct task_struct *p, int niceval, int error) |
| { |
| int no_nice; |
| |
| if (!set_one_prio_perm(p)) { |
| error = -EPERM; |
| goto out; |
| } |
| if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
| error = -EACCES; |
| goto out; |
| } |
| no_nice = security_task_setnice(p, niceval); |
| if (no_nice) { |
| error = no_nice; |
| goto out; |
| } |
| if (error == -ESRCH) |
| error = 0; |
| set_user_nice(p, niceval); |
| out: |
| return error; |
| } |
| |
| SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
| { |
| struct task_struct *g, *p; |
| struct user_struct *user; |
| const struct cred *cred = current_cred(); |
| int error = -EINVAL; |
| struct pid *pgrp; |
| kuid_t uid; |
| |
| if (which > PRIO_USER || which < PRIO_PROCESS) |
| goto out; |
| |
| /* normalize: avoid signed division (rounding problems) */ |
| error = -ESRCH; |
| if (niceval < MIN_NICE) |
| niceval = MIN_NICE; |
| if (niceval > MAX_NICE) |
| niceval = MAX_NICE; |
| |
| rcu_read_lock(); |
| read_lock(&tasklist_lock); |
| switch (which) { |
| case PRIO_PROCESS: |
| if (who) |
| p = find_task_by_vpid(who); |
| else |
| p = current; |
| if (p) |
| error = set_one_prio(p, niceval, error); |
| break; |
| case PRIO_PGRP: |
| if (who) |
| pgrp = find_vpid(who); |
| else |
| pgrp = task_pgrp(current); |
| do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
| error = set_one_prio(p, niceval, error); |
| } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
| break; |
| case PRIO_USER: |
| uid = make_kuid(cred->user_ns, who); |
| user = cred->user; |
| if (!who) |
| uid = cred->uid; |
| else if (!uid_eq(uid, cred->uid)) { |
| user = find_user(uid); |
| if (!user) |
| goto out_unlock; /* No processes for this user */ |
| } |
| do_each_thread(g, p) { |
| if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) |
| error = set_one_prio(p, niceval, error); |
| } while_each_thread(g, p); |
| if (!uid_eq(uid, cred->uid)) |
| free_uid(user); /* For find_user() */ |
| break; |
| } |
| out_unlock: |
| read_unlock(&tasklist_lock); |
| rcu_read_unlock(); |
| out: |
| return error; |
| } |
| |
| /* |
| * Ugh. To avoid negative return values, "getpriority()" will |
| * not return the normal nice-value, but a negated value that |
| * has been offset by 20 (ie it returns 40..1 instead of -20..19) |
| * to stay compatible. |
| */ |
| SYSCALL_DEFINE2(getpriority, int, which, int, who) |
| { |
| struct task_struct *g, *p; |
| struct user_struct *user; |
| const struct cred *cred = current_cred(); |
| long niceval, retval = -ESRCH; |
| struct pid *pgrp; |
| kuid_t uid; |
| |
| if (which > PRIO_USER || which < PRIO_PROCESS) |
| return -EINVAL; |
| |
| rcu_read_lock(); |
| read_lock(&tasklist_lock); |
| switch (which) { |
| case PRIO_PROCESS: |
| if (who) |
| p = find_task_by_vpid(who); |
| else |
| p = current; |
| if (p) { |
| niceval = nice_to_rlimit(task_nice(p)); |
| if (niceval > retval) |
| retval = niceval; |
| } |
| break; |
| case PRIO_PGRP: |
| if (who) |
| pgrp = find_vpid(who); |
| else |
| pgrp = task_pgrp(current); |
| do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
| niceval = nice_to_rlimit(task_nice(p)); |
| if (niceval > retval) |
| retval = niceval; |
| } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
| break; |
| case PRIO_USER: |
| uid = make_kuid(cred->user_ns, who); |
| user = cred->user; |
| if (!who) |
| uid = cred->uid; |
| else if (!uid_eq(uid, cred->uid)) { |
| user = find_user(uid); |
| if (!user) |
| goto out_unlock; /* No processes for this user */ |
| } |
| do_each_thread(g, p) { |
| if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) { |
| niceval = nice_to_rlimit(task_nice(p)); |
| if (niceval > retval) |
| retval = niceval; |
| } |
| } while_each_thread(g, p); |
| if (!uid_eq(uid, cred->uid)) |
| free_uid(user); /* for find_user() */ |
| break; |
| } |
| out_unlock: |
| read_unlock(&tasklist_lock); |
| rcu_read_unlock(); |
| |
| return retval; |
| } |
| |
| /* |
| * Unprivileged users may change the real gid to the effective gid |
| * or vice versa. (BSD-style) |
| * |
| * If you set the real gid at all, or set the effective gid to a value not |
| * equal to the real gid, then the saved gid is set to the new effective gid. |
| * |
| * This makes it possible for a setgid program to completely drop its |
| * privileges, which is often a useful assertion to make when you are doing |
| * a security audit over a program. |
| * |
| * The general idea is that a program which uses just setregid() will be |
| * 100% compatible with BSD. A program which uses just setgid() will be |
| * 100% compatible with POSIX with saved IDs. |
| * |
| * SMP: There are not races, the GIDs are checked only by filesystem |
| * operations (as far as semantic preservation is concerned). |
| */ |
| #ifdef CONFIG_MULTIUSER |
| long __sys_setregid(gid_t rgid, gid_t egid) |
| { |
| struct user_namespace *ns = current_user_ns(); |
| const struct cred *old; |
| struct cred *new; |
| int retval; |
| kgid_t krgid, kegid; |
| |
| krgid = make_kgid(ns, rgid); |
| kegid = make_kgid(ns, egid); |
| |
| if ((rgid != (gid_t) -1) && !gid_valid(krgid)) |
| return -EINVAL; |
| if ((egid != (gid_t) -1) && !gid_valid(kegid)) |
| return -EINVAL; |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| old = current_cred(); |
| |
| retval = -EPERM; |
| if (rgid != (gid_t) -1) { |
| if (gid_eq(old->gid, krgid) || |
| gid_eq(old->egid, krgid) || |
| ns_capable_setid(old->user_ns, CAP_SETGID)) |
| new->gid = krgid; |
| else |
| goto error; |
| } |
| if (egid != (gid_t) -1) { |
| if (gid_eq(old->gid, kegid) || |
| gid_eq(old->egid, kegid) || |
| gid_eq(old->sgid, kegid) || |
| ns_capable_setid(old->user_ns, CAP_SETGID)) |
| new->egid = kegid; |
| else |
| goto error; |
| } |
| |
| if (rgid != (gid_t) -1 || |
| (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) |
| new->sgid = new->egid; |
| new->fsgid = new->egid; |
| |
| retval = security_task_fix_setgid(new, old, LSM_SETID_RE); |
| if (retval < 0) |
| goto error; |
| |
| return commit_creds(new); |
| |
| error: |
| abort_creds(new); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
| { |
| return __sys_setregid(rgid, egid); |
| } |
| |
| /* |
| * setgid() is implemented like SysV w/ SAVED_IDS |
| * |
| * SMP: Same implicit races as above. |
| */ |
| long __sys_setgid(gid_t gid) |
| { |
| struct user_namespace *ns = current_user_ns(); |
| const struct cred *old; |
| struct cred *new; |
| int retval; |
| kgid_t kgid; |
| |
| kgid = make_kgid(ns, gid); |
| if (!gid_valid(kgid)) |
| return -EINVAL; |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| old = current_cred(); |
| |
| retval = -EPERM; |
| if (ns_capable_setid(old->user_ns, CAP_SETGID)) |
| new->gid = new->egid = new->sgid = new->fsgid = kgid; |
| else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) |
| new->egid = new->fsgid = kgid; |
| else |
| goto error; |
| |
| retval = security_task_fix_setgid(new, old, LSM_SETID_ID); |
| if (retval < 0) |
| goto error; |
| |
| return commit_creds(new); |
| |
| error: |
| abort_creds(new); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE1(setgid, gid_t, gid) |
| { |
| return __sys_setgid(gid); |
| } |
| |
| /* |
| * change the user struct in a credentials set to match the new UID |
| */ |
| static int set_user(struct cred *new) |
| { |
| struct user_struct *new_user; |
| |
| new_user = alloc_uid(new->uid); |
| if (!new_user) |
| return -EAGAIN; |
| |
| free_uid(new->user); |
| new->user = new_user; |
| return 0; |
| } |
| |
| static void flag_nproc_exceeded(struct cred *new) |
| { |
| if (new->ucounts == current_ucounts()) |
| return; |
| |
| /* |
| * We don't fail in case of NPROC limit excess here because too many |
| * poorly written programs don't check set*uid() return code, assuming |
| * it never fails if called by root. We may still enforce NPROC limit |
| * for programs doing set*uid()+execve() by harmlessly deferring the |
| * failure to the execve() stage. |
| */ |
| if (is_ucounts_overlimit(new->ucounts, UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC)) && |
| new->user != INIT_USER) |
| current->flags |= PF_NPROC_EXCEEDED; |
| else |
| current->flags &= ~PF_NPROC_EXCEEDED; |
| } |
| |
| /* |
| * Unprivileged users may change the real uid to the effective uid |
| * or vice versa. (BSD-style) |
| * |
| * If you set the real uid at all, or set the effective uid to a value not |
| * equal to the real uid, then the saved uid is set to the new effective uid. |
| * |
| * This makes it possible for a setuid program to completely drop its |
| * privileges, which is often a useful assertion to make when you are doing |
| * a security audit over a program. |
| * |
| * The general idea is that a program which uses just setreuid() will be |
| * 100% compatible with BSD. A program which uses just setuid() will be |
| * 100% compatible with POSIX with saved IDs. |
| */ |
| long __sys_setreuid(uid_t ruid, uid_t euid) |
| { |
| struct user_namespace *ns = current_user_ns(); |
| const struct cred *old; |
| struct cred *new; |
| int retval; |
| kuid_t kruid, keuid; |
| |
| kruid = make_kuid(ns, ruid); |
| keuid = make_kuid(ns, euid); |
| |
| if ((ruid != (uid_t) -1) && !uid_valid(kruid)) |
| return -EINVAL; |
| if ((euid != (uid_t) -1) && !uid_valid(keuid)) |
| return -EINVAL; |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| old = current_cred(); |
| |
| retval = -EPERM; |
| if (ruid != (uid_t) -1) { |
| new->uid = kruid; |
| if (!uid_eq(old->uid, kruid) && |
| !uid_eq(old->euid, kruid) && |
| !ns_capable_setid(old->user_ns, CAP_SETUID)) |
| goto error; |
| } |
| |
| if (euid != (uid_t) -1) { |
| new->euid = keuid; |
| if (!uid_eq(old->uid, keuid) && |
| !uid_eq(old->euid, keuid) && |
| !uid_eq(old->suid, keuid) && |
| !ns_capable_setid(old->user_ns, CAP_SETUID)) |
| goto error; |
| } |
| |
| if (!uid_eq(new->uid, old->uid)) { |
| retval = set_user(new); |
| if (retval < 0) |
| goto error; |
| } |
| if (ruid != (uid_t) -1 || |
| (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) |
| new->suid = new->euid; |
| new->fsuid = new->euid; |
| |
| retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
| if (retval < 0) |
| goto error; |
| |
| retval = set_cred_ucounts(new); |
| if (retval < 0) |
| goto error; |
| |
| flag_nproc_exceeded(new); |
| return commit_creds(new); |
| |
| error: |
| abort_creds(new); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
| { |
| return __sys_setreuid(ruid, euid); |
| } |
| |
| /* |
| * setuid() is implemented like SysV with SAVED_IDS |
| * |
| * Note that SAVED_ID's is deficient in that a setuid root program |
| * like sendmail, for example, cannot set its uid to be a normal |
| * user and then switch back, because if you're root, setuid() sets |
| * the saved uid too. If you don't like this, blame the bright people |
| * in the POSIX committee and/or USG. Note that the BSD-style setreuid() |
| * will allow a root program to temporarily drop privileges and be able to |
| * regain them by swapping the real and effective uid. |
| */ |
| long __sys_setuid(uid_t uid) |
| { |
| struct user_namespace *ns = current_user_ns(); |
| const struct cred *old; |
| struct cred *new; |
| int retval; |
| kuid_t kuid; |
| |
| kuid = make_kuid(ns, uid); |
| if (!uid_valid(kuid)) |
| return -EINVAL; |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| old = current_cred(); |
| |
| retval = -EPERM; |
| if (ns_capable_setid(old->user_ns, CAP_SETUID)) { |
| new->suid = new->uid = kuid; |
| if (!uid_eq(kuid, old->uid)) { |
| retval = set_user(new); |
| if (retval < 0) |
| goto error; |
| } |
| } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { |
| goto error; |
| } |
| |
| new->fsuid = new->euid = kuid; |
| |
| retval = security_task_fix_setuid(new, old, LSM_SETID_ID); |
| if (retval < 0) |
| goto error; |
| |
| retval = set_cred_ucounts(new); |
| if (retval < 0) |
| goto error; |
| |
| flag_nproc_exceeded(new); |
| return commit_creds(new); |
| |
| error: |
| abort_creds(new); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE1(setuid, uid_t, uid) |
| { |
| return __sys_setuid(uid); |
| } |
| |
| |
| /* |
| * This function implements a generic ability to update ruid, euid, |
| * and suid. This allows you to implement the 4.4 compatible seteuid(). |
| */ |
| long __sys_setresuid(uid_t ruid, uid_t euid, uid_t suid) |
| { |
| struct user_namespace *ns = current_user_ns(); |
| const struct cred *old; |
| struct cred *new; |
| int retval; |
| kuid_t kruid, keuid, ksuid; |
| bool ruid_new, euid_new, suid_new; |
| |
| kruid = make_kuid(ns, ruid); |
| keuid = make_kuid(ns, euid); |
| ksuid = make_kuid(ns, suid); |
| |
| if ((ruid != (uid_t) -1) && !uid_valid(kruid)) |
| return -EINVAL; |
| |
| if ((euid != (uid_t) -1) && !uid_valid(keuid)) |
| return -EINVAL; |
| |
| if ((suid != (uid_t) -1) && !uid_valid(ksuid)) |
| return -EINVAL; |
| |
| old = current_cred(); |
| |
| /* check for no-op */ |
| if ((ruid == (uid_t) -1 || uid_eq(kruid, old->uid)) && |
| (euid == (uid_t) -1 || (uid_eq(keuid, old->euid) && |
| uid_eq(keuid, old->fsuid))) && |
| (suid == (uid_t) -1 || uid_eq(ksuid, old->suid))) |
| return 0; |
| |
| ruid_new = ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && |
| !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid); |
| euid_new = euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && |
| !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid); |
| suid_new = suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && |
| !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid); |
| if ((ruid_new || euid_new || suid_new) && |
| !ns_capable_setid(old->user_ns, CAP_SETUID)) |
| return -EPERM; |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| |
| if (ruid != (uid_t) -1) { |
| new->uid = kruid; |
| if (!uid_eq(kruid, old->uid)) { |
| retval = set_user(new); |
| if (retval < 0) |
| goto error; |
| } |
| } |
| if (euid != (uid_t) -1) |
| new->euid = keuid; |
| if (suid != (uid_t) -1) |
| new->suid = ksuid; |
| new->fsuid = new->euid; |
| |
| retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
| if (retval < 0) |
| goto error; |
| |
| retval = set_cred_ucounts(new); |
| if (retval < 0) |
| goto error; |
| |
| flag_nproc_exceeded(new); |
| return commit_creds(new); |
| |
| error: |
| abort_creds(new); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
| { |
| return __sys_setresuid(ruid, euid, suid); |
| } |
| |
| SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) |
| { |
| const struct cred *cred = current_cred(); |
| int retval; |
| uid_t ruid, euid, suid; |
| |
| ruid = from_kuid_munged(cred->user_ns, cred->uid); |
| euid = from_kuid_munged(cred->user_ns, cred->euid); |
| suid = from_kuid_munged(cred->user_ns, cred->suid); |
| |
| retval = put_user(ruid, ruidp); |
| if (!retval) { |
| retval = put_user(euid, euidp); |
| if (!retval) |
| return put_user(suid, suidp); |
| } |
| return retval; |
| } |
| |
| /* |
| * Same as above, but for rgid, egid, sgid. |
| */ |
| long __sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid) |
| { |
| struct user_namespace *ns = current_user_ns(); |
| const struct cred *old; |
| struct cred *new; |
| int retval; |
| kgid_t krgid, kegid, ksgid; |
| bool rgid_new, egid_new, sgid_new; |
| |
| krgid = make_kgid(ns, rgid); |
| kegid = make_kgid(ns, egid); |
| ksgid = make_kgid(ns, sgid); |
| |
| if ((rgid != (gid_t) -1) && !gid_valid(krgid)) |
| return -EINVAL; |
| if ((egid != (gid_t) -1) && !gid_valid(kegid)) |
| return -EINVAL; |
| if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) |
| return -EINVAL; |
| |
| old = current_cred(); |
| |
| /* check for no-op */ |
| if ((rgid == (gid_t) -1 || gid_eq(krgid, old->gid)) && |
| (egid == (gid_t) -1 || (gid_eq(kegid, old->egid) && |
| gid_eq(kegid, old->fsgid))) && |
| (sgid == (gid_t) -1 || gid_eq(ksgid, old->sgid))) |
| return 0; |
| |
| rgid_new = rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && |
| !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid); |
| egid_new = egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && |
| !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid); |
| sgid_new = sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && |
| !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid); |
| if ((rgid_new || egid_new || sgid_new) && |
| !ns_capable_setid(old->user_ns, CAP_SETGID)) |
| return -EPERM; |
| |
| new = prepare_creds(); |
| if (!new) |
| return -ENOMEM; |
| |
| if (rgid != (gid_t) -1) |
| new->gid = krgid; |
| if (egid != (gid_t) -1) |
| new->egid = kegid; |
| if (sgid != (gid_t) -1) |
| new->sgid = ksgid; |
| new->fsgid = new->egid; |
| |
| retval = security_task_fix_setgid(new, old, LSM_SETID_RES); |
| if (retval < 0) |
| goto error; |
| |
| return commit_creds(new); |
| |
| error: |
| abort_creds(new); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
| { |
| return __sys_setresgid(rgid, egid, sgid); |
| } |
| |
| SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) |
| { |
| const struct cred *cred = current_cred(); |
| int retval; |
| gid_t rgid, egid, sgid; |
| |
| rgid = from_kgid_munged(cred->user_ns, cred->gid); |
| egid = from_kgid_munged(cred->user_ns, cred->egid); |
| sgid = from_kgid_munged(cred->user_ns, cred->sgid); |
| |
| retval = put_user(rgid, rgidp); |
| if (!retval) { |
| retval = put_user(egid, egidp); |
| if (!retval) |
| retval = put_user(sgid, sgidp); |
| } |
| |
| return retval; |
| } |
| |
| |
| /* |
| * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This |
| * is used for "access()" and for the NFS daemon (letting nfsd stay at |
| * whatever uid it wants to). It normally shadows "euid", except when |
| * explicitly set by setfsuid() or for access.. |
| */ |
| long __sys_setfsuid(uid_t uid) |
| { |
| const struct cred *old; |
| struct cred *new; |
| uid_t old_fsuid; |
| kuid_t kuid; |
| |
| old = current_cred(); |
| old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); |
| |
| kuid = make_kuid(old->user_ns, uid); |
| if (!uid_valid(kuid)) |
| return old_fsuid; |
| |
| new = prepare_creds(); |
| if (!new) |
| return old_fsuid; |
| |
| if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || |
| uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || |
| ns_capable_setid(old->user_ns, CAP_SETUID)) { |
| if (!uid_eq(kuid, old->fsuid)) { |
| new->fsuid = kuid; |
| if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) |
| goto change_okay; |
| } |
| } |
| |
| abort_creds(new); |
| return old_fsuid; |
| |
| change_okay: |
| commit_creds(new); |
| return old_fsuid; |
| } |
| |
| SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
| { |
| return __sys_setfsuid(uid); |
| } |
| |
| /* |
| * Samma på svenska.. |
| */ |
| long __sys_setfsgid(gid_t gid) |
| { |
| const struct cred *old; |
| struct cred *new; |
| gid_t old_fsgid; |
| kgid_t kgid; |
| |
| old = current_cred(); |
| old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); |
| |
| kgid = make_kgid(old->user_ns, gid); |
| if (!gid_valid(kgid)) |
| return old_fsgid; |
| |
| new = prepare_creds(); |
| if (!new) |
| return old_fsgid; |
| |
| if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || |
| gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || |
| ns_capable_setid(old->user_ns, CAP_SETGID)) { |
| if (!gid_eq(kgid, old->fsgid)) { |
| new->fsgid = kgid; |
| if (security_task_fix_setgid(new,old,LSM_SETID_FS) == 0) |
| goto change_okay; |
| } |
| } |
| |
| abort_creds(new); |
| return old_fsgid; |
| |
| change_okay: |
| commit_creds(new); |
| return old_fsgid; |
| } |
| |
| SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
| { |
| return __sys_setfsgid(gid); |
| } |
| #endif /* CONFIG_MULTIUSER */ |
| |
| /** |
| * sys_getpid - return the thread group id of the current process |
| * |
| * Note, despite the name, this returns the tgid not the pid. The tgid and |
| * the pid are identical unless CLONE_THREAD was specified on clone() in |
| * which case the tgid is the same in all threads of the same group. |
| * |
| * This is SMP safe as current->tgid does not change. |
| */ |
| SYSCALL_DEFINE0(getpid) |
| { |
| return task_tgid_vnr(current); |
| } |
| |
| /* Thread ID - the internal kernel "pid" */ |
| SYSCALL_DEFINE0(gettid) |
| { |
| return task_pid_vnr(current); |
| } |
| |
| /* |
| * Accessing ->real_parent is not SMP-safe, it could |
| * change from under us. However, we can use a stale |
| * value of ->real_parent under rcu_read_lock(), see |
| * release_task()->call_rcu(delayed_put_task_struct). |
| */ |
| SYSCALL_DEFINE0(getppid) |
| { |
| int pid; |
| |
| rcu_read_lock(); |
| pid = task_tgid_vnr(rcu_dereference(current->real_parent)); |
| rcu_read_unlock(); |
| |
| return pid; |
| } |
| |
| SYSCALL_DEFINE0(getuid) |
| { |
| /* Only we change this so SMP safe */ |
| return from_kuid_munged(current_user_ns(), current_uid()); |
| } |
| |
| SYSCALL_DEFINE0(geteuid) |
| { |
| /* Only we change this so SMP safe */ |
| return from_kuid_munged(current_user_ns(), current_euid()); |
| } |
| |
| SYSCALL_DEFINE0(getgid) |
| { |
| /* Only we change this so SMP safe */ |
| return from_kgid_munged(current_user_ns(), current_gid()); |
| } |
| |
| SYSCALL_DEFINE0(getegid) |
| { |
| /* Only we change this so SMP safe */ |
| return from_kgid_munged(current_user_ns(), current_egid()); |
| } |
| |
| static void do_sys_times(struct tms *tms) |
| { |
| u64 tgutime, tgstime, cutime, cstime; |
| |
| thread_group_cputime_adjusted(current, &tgutime, &tgstime); |
| cutime = current->signal->cutime; |
| cstime = current->signal->cstime; |
| tms->tms_utime = nsec_to_clock_t(tgutime); |
| tms->tms_stime = nsec_to_clock_t(tgstime); |
| tms->tms_cutime = nsec_to_clock_t(cutime); |
| tms->tms_cstime = nsec_to_clock_t(cstime); |
| } |
| |
| SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
| { |
| if (tbuf) { |
| struct tms tmp; |
| |
| do_sys_times(&tmp); |
| if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
| return -EFAULT; |
| } |
| force_successful_syscall_return(); |
| return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
| } |
| |
| #ifdef CONFIG_COMPAT |
| static compat_clock_t clock_t_to_compat_clock_t(clock_t x) |
| { |
| return compat_jiffies_to_clock_t(clock_t_to_jiffies(x)); |
| } |
| |
| COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf) |
| { |
| if (tbuf) { |
| struct tms tms; |
| struct compat_tms tmp; |
| |
| do_sys_times(&tms); |
| /* Convert our struct tms to the compat version. */ |
| tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime); |
| tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime); |
| tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime); |
| tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime); |
| if (copy_to_user(tbuf, &tmp, sizeof(tmp))) |
| return -EFAULT; |
| } |
| force_successful_syscall_return(); |
| return compat_jiffies_to_clock_t(jiffies); |
| } |
| #endif |
| |
| /* |
| * This needs some heavy checking ... |
| * I just haven't the stomach for it. I also don't fully |
| * understand sessions/pgrp etc. Let somebody who does explain it. |
| * |
| * OK, I think I have the protection semantics right.... this is really |
| * only important on a multi-user system anyway, to make sure one user |
| * can't send a signal to a process owned by another. -TYT, 12/12/91 |
| * |
| * !PF_FORKNOEXEC check to conform completely to POSIX. |
| */ |
| SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
| { |
| struct task_struct *p; |
| struct task_struct *group_leader = current->group_leader; |
| struct pid *pgrp; |
| int err; |
| |
| if (!pid) |
| pid = task_pid_vnr(group_leader); |
| if (!pgid) |
| pgid = pid; |
| if (pgid < 0) |
| return -EINVAL; |
| rcu_read_lock(); |
| |
| /* From this point forward we keep holding onto the tasklist lock |
| * so that our parent does not change from under us. -DaveM |
| */ |
| write_lock_irq(&tasklist_lock); |
| |
| err = -ESRCH; |
| p = find_task_by_vpid(pid); |
| if (!p) |
| goto out; |
| |
| err = -EINVAL; |
| if (!thread_group_leader(p)) |
| goto out; |
| |
| if (same_thread_group(p->real_parent, group_leader)) { |
| err = -EPERM; |
| if (task_session(p) != task_session(group_leader)) |
| goto out; |
| err = -EACCES; |
| if (!(p->flags & PF_FORKNOEXEC)) |
| goto out; |
| } else { |
| err = -ESRCH; |
| if (p != group_leader) |
| goto out; |
| } |
| |
| err = -EPERM; |
| if (p->signal->leader) |
| goto out; |
| |
| pgrp = task_pid(p); |
| if (pgid != pid) { |
| struct task_struct *g; |
| |
| pgrp = find_vpid(pgid); |
| g = pid_task(pgrp, PIDTYPE_PGID); |
| if (!g || task_session(g) != task_session(group_leader)) |
| goto out; |
| } |
| |
| err = security_task_setpgid(p, pgid); |
| if (err) |
| goto out; |
| |
| if (task_pgrp(p) != pgrp) |
| change_pid(p, PIDTYPE_PGID, pgrp); |
| |
| err = 0; |
| out: |
| /* All paths lead to here, thus we are safe. -DaveM */ |
| write_unlock_irq(&tasklist_lock); |
| rcu_read_unlock(); |
| return err; |
| } |
| |
| static int do_getpgid(pid_t pid) |
| { |
| struct task_struct *p; |
| struct pid *grp; |
| int retval; |
| |
| rcu_read_lock(); |
| if (!pid) |
| grp = task_pgrp(current); |
| else { |
| retval = -ESRCH; |
| p = find_task_by_vpid(pid); |
| if (!p) |
| goto out; |
| grp = task_pgrp(p); |
| if (!grp) |
| goto out; |
| |
| retval = security_task_getpgid(p); |
| if (retval) |
| goto out; |
| } |
| retval = pid_vnr(grp); |
| out: |
| rcu_read_unlock(); |
| return retval; |
| } |
| |
| SYSCALL_DEFINE1(getpgid, pid_t, pid) |
| { |
| return do_getpgid(pid); |
| } |
| |
| #ifdef __ARCH_WANT_SYS_GETPGRP |
| |
| SYSCALL_DEFINE0(getpgrp) |
| { |
| return do_getpgid(0); |
| } |
| |
| #endif |
| |
| SYSCALL_DEFINE1(getsid, pid_t, pid) |
| { |
| struct task_struct *p; |
| struct pid *sid; |
| int retval; |
| |
| rcu_read_lock(); |
| if (!pid) |
| sid = task_session(current); |
| else { |
| retval = -ESRCH; |
| p = find_task_by_vpid(pid); |
| if (!p) |
| goto out; |
| sid = task_session(p); |
| if (!sid) |
| goto out; |
| |
| retval = security_task_getsid(p); |
| if (retval) |
| goto out; |
| } |
| retval = pid_vnr(sid); |
| out: |
| rcu_read_unlock(); |
| return retval; |
| } |
| |
| static void set_special_pids(struct pid *pid) |
| { |
| struct task_struct *curr = current->group_leader; |
| |
| if (task_session(curr) != pid) |
| change_pid(curr, PIDTYPE_SID, pid); |
| |
| if (task_pgrp(curr) != pid) |
| change_pid(curr, PIDTYPE_PGID, pid); |
| } |
| |
| int ksys_setsid(void) |
| { |
| struct task_struct *group_leader = current->group_leader; |
| struct pid *sid = task_pid(group_leader); |
| pid_t session = pid_vnr(sid); |
| int err = -EPERM; |
| |
| write_lock_irq(&tasklist_lock); |
| /* Fail if I am already a session leader */ |
| if (group_leader->signal->leader) |
| goto out; |
| |
| /* Fail if a process group id already exists that equals the |
| * proposed session id. |
| */ |
| if (pid_task(sid, PIDTYPE_PGID)) |
| goto out; |
| |
| group_leader->signal->leader = 1; |
| set_special_pids(sid); |
| |
| proc_clear_tty(group_leader); |
| |
| err = session; |
| out: |
| write_unlock_irq(&tasklist_lock); |
| if (err > 0) { |
| proc_sid_connector(group_leader); |
| sched_autogroup_create_attach(group_leader); |
| } |
| return err; |
| } |
| |
| SYSCALL_DEFINE0(setsid) |
| { |
| return ksys_setsid(); |
| } |
| |
| DECLARE_RWSEM(uts_sem); |
| |
| #ifdef COMPAT_UTS_MACHINE |
| #define override_architecture(name) \ |
| (personality(current->personality) == PER_LINUX32 && \ |
| copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ |
| sizeof(COMPAT_UTS_MACHINE))) |
| #else |
| #define override_architecture(name) 0 |
| #endif |
| |
| /* |
| * Work around broken programs that cannot handle "Linux 3.0". |
| * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 |
| * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be |
| * 2.6.60. |
| */ |
| static int override_release(char __user *release, size_t len) |
| { |
| int ret = 0; |
| |
| if (current->personality & UNAME26) { |
| const char *rest = UTS_RELEASE; |
| char buf[65] = { 0 }; |
| int ndots = 0; |
| unsigned v; |
| size_t copy; |
| |
| while (*rest) { |
| if (*rest == '.' && ++ndots >= 3) |
| break; |
| if (!isdigit(*rest) && *rest != '.') |
| break; |
| rest++; |
| } |
| v = LINUX_VERSION_PATCHLEVEL + 60; |
| copy = clamp_t(size_t, len, 1, sizeof(buf)); |
| copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); |
| ret = copy_to_user(release, buf, copy + 1); |
| } |
| return ret; |
| } |
| |
| SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
| { |
| struct new_utsname tmp; |
| |
| down_read(&uts_sem); |
| memcpy(&tmp, utsname(), sizeof(tmp)); |
| up_read(&uts_sem); |
| if (copy_to_user(name, &tmp, sizeof(tmp))) |
| return -EFAULT; |
| |
| if (override_release(name->release, sizeof(name->release))) |
| return -EFAULT; |
| if (override_architecture(name)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| #ifdef __ARCH_WANT_SYS_OLD_UNAME |
| /* |
| * Old cruft |
| */ |
| SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) |
| { |
| struct old_utsname tmp; |
| |
| if (!name) |
| return -EFAULT; |
| |
| down_read(&uts_sem); |
| memcpy(&tmp, utsname(), sizeof(tmp)); |
| up_read(&uts_sem); |
| if (copy_to_user(name, &tmp, sizeof(tmp))) |
| return -EFAULT; |
| |
| if (override_release(name->release, sizeof(name->release))) |
| return -EFAULT; |
| if (override_architecture(name)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) |
| { |
| struct oldold_utsname tmp; |
| |
| if (!name) |
| return -EFAULT; |
| |
| memset(&tmp, 0, sizeof(tmp)); |
| |
| down_read(&uts_sem); |
| memcpy(&tmp.sysname, &utsname()->sysname, __OLD_UTS_LEN); |
| memcpy(&tmp.nodename, &utsname()->nodename, __OLD_UTS_LEN); |
| memcpy(&tmp.release, &utsname()->release, __OLD_UTS_LEN); |
| memcpy(&tmp.version, &utsname()->version, __OLD_UTS_LEN); |
| memcpy(&tmp.machine, &utsname()->machine, __OLD_UTS_LEN); |
| up_read(&uts_sem); |
| if (copy_to_user(name, &tmp, sizeof(tmp))) |
| return -EFAULT; |
| |
| if (override_architecture(name)) |
| return -EFAULT; |
| if (override_release(name->release, sizeof(name->release))) |
| return -EFAULT; |
| return 0; |
| } |
| #endif |
| |
| SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
| { |
| int errno; |
| char tmp[__NEW_UTS_LEN]; |
| |
| if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
| return -EPERM; |
| |
| if (len < 0 || len > __NEW_UTS_LEN) |
| return -EINVAL; |
| errno = -EFAULT; |
| if (!copy_from_user(tmp, name, len)) { |
| struct new_utsname *u; |
| |
| down_write(&uts_sem); |
| u = utsname(); |
| memcpy(u->nodename, tmp, len); |
| memset(u->nodename + len, 0, sizeof(u->nodename) - len); |
| errno = 0; |
| uts_proc_notify(UTS_PROC_HOSTNAME); |
| up_write(&uts_sem); |
| } |
| return errno; |
| } |
| |
| #ifdef __ARCH_WANT_SYS_GETHOSTNAME |
| |
| SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
| { |
| int i; |
| struct new_utsname *u; |
| char tmp[__NEW_UTS_LEN + 1]; |
| |
| if (len < 0) |
| return -EINVAL; |
| down_read(&uts_sem); |
| u = utsname(); |
| i = 1 + strlen(u->nodename); |
| if (i > len) |
| i = len; |
| memcpy(tmp, u->nodename, i); |
| up_read(&uts_sem); |
| if (copy_to_user(name, tmp, i)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| #endif |
| |
| /* |
| * Only setdomainname; getdomainname can be implemented by calling |
| * uname() |
| */ |
| SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
| { |
| int errno; |
| char tmp[__NEW_UTS_LEN]; |
| |
| if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
| return -EPERM; |
| if (len < 0 || len > __NEW_UTS_LEN) |
| return -EINVAL; |
| |
| errno = -EFAULT; |
| if (!copy_from_user(tmp, name, len)) { |
| struct new_utsname *u; |
| |
| down_write(&uts_sem); |
| u = utsname(); |
| memcpy(u->domainname, tmp, len); |
| memset(u->domainname + len, 0, sizeof(u->domainname) - len); |
| errno = 0; |
| uts_proc_notify(UTS_PROC_DOMAINNAME); |
| up_write(&uts_sem); |
| } |
| return errno; |
| } |
| |
| SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
| { |
| struct rlimit value; |
| int ret; |
| |
| ret = do_prlimit(current, resource, NULL, &value); |
| if (!ret) |
| ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; |
| |
| return ret; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| |
| COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource, |
| struct compat_rlimit __user *, rlim) |
| { |
| struct rlimit r; |
| struct compat_rlimit r32; |
| |
| if (copy_from_user(&r32, rlim, sizeof(struct compat_rlimit))) |
| return -EFAULT; |
| |
| if (r32.rlim_cur == COMPAT_RLIM_INFINITY) |
| r.rlim_cur = RLIM_INFINITY; |
| else |
| r.rlim_cur = r32.rlim_cur; |
| if (r32.rlim_max == COMPAT_RLIM_INFINITY) |
| r.rlim_max = RLIM_INFINITY; |
| else |
| r.rlim_max = r32.rlim_max; |
| return do_prlimit(current, resource, &r, NULL); |
| } |
| |
| COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource, |
| struct compat_rlimit __user *, rlim) |
| { |
| struct rlimit r; |
| int ret; |
| |
| ret = do_prlimit(current, resource, NULL, &r); |
| if (!ret) { |
| struct compat_rlimit r32; |
| if (r.rlim_cur > COMPAT_RLIM_INFINITY) |
| r32.rlim_cur = COMPAT_RLIM_INFINITY; |
| else |
| r32.rlim_cur = r.rlim_cur; |
| if (r.rlim_max > COMPAT_RLIM_INFINITY) |
| r32.rlim_max = COMPAT_RLIM_INFINITY; |
| else |
| r32.rlim_max = r.rlim_max; |
| |
| if (copy_to_user(rlim, &r32, sizeof(struct compat_rlimit))) |
| return -EFAULT; |
| } |
| return ret; |
| } |
| |
| #endif |
| |
| #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT |
| |
| /* |
| * Back compatibility for getrlimit. Needed for some apps. |
| */ |
| SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
| struct rlimit __user *, rlim) |
| { |
| struct rlimit x; |
| if (resource >= RLIM_NLIMITS) |
| return -EINVAL; |
| |
| resource = array_index_nospec(resource, RLIM_NLIMITS); |
| task_lock(current->group_leader); |
| x = current->signal->rlim[resource]; |
| task_unlock(current->group_leader); |
| if (x.rlim_cur > 0x7FFFFFFF) |
| x.rlim_cur = 0x7FFFFFFF; |
| if (x.rlim_max > 0x7FFFFFFF) |
| x.rlim_max = 0x7FFFFFFF; |
| return copy_to_user(rlim, &x, sizeof(x)) ? -EFAULT : 0; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
| struct compat_rlimit __user *, rlim) |
| { |
| struct rlimit r; |
| |
| if (resource >= RLIM_NLIMITS) |
| return -EINVAL; |
| |
| resource = array_index_nospec(resource, RLIM_NLIMITS); |
| task_lock(current->group_leader); |
| r = current->signal->rlim[resource]; |
| task_unlock(current->group_leader); |
| if (r.rlim_cur > 0x7FFFFFFF) |
| r.rlim_cur = 0x7FFFFFFF; |
| if (r.rlim_max > 0x7FFFFFFF) |
| r.rlim_max = 0x7FFFFFFF; |
| |
| if (put_user(r.rlim_cur, &rlim->rlim_cur) || |
| put_user(r.rlim_max, &rlim->rlim_max)) |
| return -EFAULT; |
| return 0; |
| } |
| #endif |
| |
| #endif |
| |
| static inline bool rlim64_is_infinity(__u64 rlim64) |
| { |
| #if BITS_PER_LONG < 64 |
| return rlim64 >= ULONG_MAX; |
| #else |
| return rlim64 == RLIM64_INFINITY; |
| #endif |
| } |
| |
| static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) |
| { |
| if (rlim->rlim_cur == RLIM_INFINITY) |
| rlim64->rlim_cur = RLIM64_INFINITY; |
| else |
| rlim64->rlim_cur = rlim->rlim_cur; |
| if (rlim->rlim_max == RLIM_INFINITY) |
| rlim64->rlim_max = RLIM64_INFINITY; |
| else |
| rlim64->rlim_max = rlim->rlim_max; |
| } |
| |
| static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) |
| { |
| if (rlim64_is_infinity(rlim64->rlim_cur)) |
| rlim->rlim_cur = RLIM_INFINITY; |
| else |
| rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; |
| if (rlim64_is_infinity(rlim64->rlim_max)) |
| rlim->rlim_max = RLIM_INFINITY; |
| else |
| rlim->rlim_max = (unsigned long)rlim64->rlim_max; |
| } |
| |
| /* make sure you are allowed to change @tsk limits before calling this */ |
| int do_prlimit(struct task_struct *tsk, unsigned int resource, |
| struct rlimit *new_rlim, struct rlimit *old_rlim) |
| { |
| struct rlimit *rlim; |
| int retval = 0; |
| |
| if (resource >= RLIM_NLIMITS) |
| return -EINVAL; |
| resource = array_index_nospec(resource, RLIM_NLIMITS); |
| |
| if (new_rlim) { |
| if (new_rlim->rlim_cur > new_rlim->rlim_max) |
| return -EINVAL; |
| if (resource == RLIMIT_NOFILE && |
| new_rlim->rlim_max > sysctl_nr_open) |
| return -EPERM; |
| } |
| |
| /* protect tsk->signal and tsk->sighand from disappearing */ |
| read_lock(&tasklist_lock); |
| if (!tsk->sighand) { |
| retval = -ESRCH; |
| goto out; |
| } |
| |
| rlim = tsk->signal->rlim + resource; |
| task_lock(tsk->group_leader); |
| if (new_rlim) { |
| /* Keep the capable check against init_user_ns until |
| cgroups can contain all limits */ |
| if (new_rlim->rlim_max > rlim->rlim_max && |
| !capable(CAP_SYS_RESOURCE)) |
| retval = -EPERM; |
| if (!retval) |
| retval = security_task_setrlimit(tsk, resource, new_rlim); |
| } |
| if (!retval) { |
| if (old_rlim) |
| *old_rlim = *rlim; |
| if (new_rlim) |
| *rlim = *new_rlim; |
| } |
| task_unlock(tsk->group_leader); |
| |
| /* |
| * RLIMIT_CPU handling. Arm the posix CPU timer if the limit is not |
| * infinite. In case of RLIM_INFINITY the posix CPU timer code |
| * ignores the rlimit. |
| */ |
| if (!retval && new_rlim && resource == RLIMIT_CPU && |
| new_rlim->rlim_cur != RLIM_INFINITY && |
| IS_ENABLED(CONFIG_POSIX_TIMERS)) |
| update_rlimit_cpu(tsk, new_rlim->rlim_cur); |
| out: |
| read_unlock(&tasklist_lock); |
| return retval; |
| } |
| |
| /* rcu lock must be held */ |
| static int check_prlimit_permission(struct task_struct *task, |
| unsigned int flags) |
| { |
| const struct cred *cred = current_cred(), *tcred; |
| bool id_match; |
| |
| if (current == task) |
| return 0; |
| |
| tcred = __task_cred(task); |
| id_match = (uid_eq(cred->uid, tcred->euid) && |
| uid_eq(cred->uid, tcred->suid) && |
| uid_eq(cred->uid, tcred->uid) && |
| gid_eq(cred->gid, tcred->egid) && |
| gid_eq(cred->gid, tcred->sgid) && |
| gid_eq(cred->gid, tcred->gid)); |
| if (!id_match && !ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) |
| return -EPERM; |
| |
| return security_task_prlimit(cred, tcred, flags); |
| } |
| |
| SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, |
| const struct rlimit64 __user *, new_rlim, |
| struct rlimit64 __user *, old_rlim) |
| { |
| struct rlimit64 old64, new64; |
| struct rlimit old, new; |
| struct task_struct *tsk; |
| unsigned int checkflags = 0; |
| int ret; |
| |
| if (old_rlim) |
| checkflags |= LSM_PRLIMIT_READ; |
| |
| if (new_rlim) { |
| if (copy_from_user(&new64, new_rlim, sizeof(new64))) |
| return -EFAULT; |
| rlim64_to_rlim(&new64, &new); |
| checkflags |= LSM_PRLIMIT_WRITE; |
| } |
| |
| rcu_read_lock(); |
| tsk = pid ? find_task_by_vpid(pid) : current; |
| if (!tsk) { |
| rcu_read_unlock(); |
| return -ESRCH; |
| } |
| ret = check_prlimit_permission(tsk, checkflags); |
| if (ret) { |
| rcu_read_unlock(); |
| return ret; |
| } |
| get_task_struct(tsk); |
| rcu_read_unlock(); |
| |
| ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, |
| old_rlim ? &old : NULL); |
| |
| if (!ret && old_rlim) { |
| rlim_to_rlim64(&old, &old64); |
| if (copy_to_user(old_rlim, &old64, sizeof(old64))) |
| ret = -EFAULT; |
| } |
| |
| put_task_struct(tsk); |
| return ret; |
| } |
| |
| SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
| { |
| struct rlimit new_rlim; |
| |
| if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) |
| return -EFAULT; |
| return do_prlimit(current, resource, &new_rlim, NULL); |
| } |
| |
| /* |
| * It would make sense to put struct rusage in the task_struct, |
| * except that would make the task_struct be *really big*. After |
| * task_struct gets moved into malloc'ed memory, it would |
| * make sense to do this. It will make moving the rest of the information |
| * a lot simpler! (Which we're not doing right now because we're not |
| * measuring them yet). |
| * |
| * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
| * races with threads incrementing their own counters. But since word |
| * reads are atomic, we either get new values or old values and we don't |
| * care which for the sums. We always take the siglock to protect reading |
| * the c* fields from p->signal from races with exit.c updating those |
| * fields when reaping, so a sample either gets all the additions of a |
| * given child after it's reaped, or none so this sample is before reaping. |
| * |
| * Locking: |
| * We need to take the siglock for CHILDEREN, SELF and BOTH |
| * for the cases current multithreaded, non-current single threaded |
| * non-current multithreaded. Thread traversal is now safe with |
| * the siglock held. |
| * Strictly speaking, we donot need to take the siglock if we are current and |
| * single threaded, as no one else can take our signal_struct away, no one |
| * else can reap the children to update signal->c* counters, and no one else |
| * can race with the signal-> fields. If we do not take any lock, the |
| * signal-> fields could be read out of order while another thread was just |
| * exiting. So we should place a read memory barrier when we avoid the lock. |
| * On the writer side, write memory barrier is implied in __exit_signal |
| * as __exit_signal releases the siglock spinlock after updating the signal-> |
| * fields. But we don't do this yet to keep things simple. |
| * |
| */ |
| |
| static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
| { |
| r->ru_nvcsw += t->nvcsw; |
| r->ru_nivcsw += t->nivcsw; |
| r->ru_minflt += t->min_flt; |
| r->ru_majflt += t->maj_flt; |
| r->ru_inblock += task_io_get_inblock(t); |
| r->ru_oublock += task_io_get_oublock(t); |
| } |
| |
| void getrusage(struct task_struct *p, int who, struct rusage *r) |
| { |
| struct task_struct *t; |
| unsigned long flags; |
| u64 tgutime, tgstime, utime, stime; |
| unsigned long maxrss = 0; |
| |
| memset((char *)r, 0, sizeof (*r)); |
| utime = stime = 0; |
| |
| if (who == RUSAGE_THREAD) { |
| task_cputime_adjusted(current, &utime, &stime); |
| accumulate_thread_rusage(p, r); |
| maxrss = p->signal->maxrss; |
| goto out; |
| } |
| |
| if (!lock_task_sighand(p, &flags)) |
| return; |
| |
| switch (who) { |
| case RUSAGE_BOTH: |
| case RUSAGE_CHILDREN: |
| utime = p->signal->cutime; |
| stime = p->signal->cstime; |
| r->ru_nvcsw = p->signal->cnvcsw; |
| r->ru_nivcsw = p->signal->cnivcsw; |
| r->ru_minflt = p->signal->cmin_flt; |
| r->ru_majflt = p->signal->cmaj_flt; |
| r->ru_inblock = p->signal->cinblock; |
| r->ru_oublock = p->signal->coublock; |
| maxrss = p->signal->cmaxrss; |
| |
| if (who == RUSAGE_CHILDREN) |
| break; |
| fallthrough; |
| |
| case RUSAGE_SELF: |
| thread_group_cputime_adjusted(p, &tgutime, &tgstime); |
| utime += tgutime; |
| stime += tgstime; |
| r->ru_nvcsw += p->signal->nvcsw; |
| r->ru_nivcsw += p->signal->nivcsw; |
| r->ru_minflt += p->signal->min_flt; |
| r->ru_majflt += p->signal->maj_flt; |
| r->ru_inblock += p->signal->inblock; |
| r->ru_oublock += p->signal->oublock; |
| if (maxrss < p->signal->maxrss) |
| maxrss = p->signal->maxrss; |
| t = p; |
| do { |
| accumulate_thread_rusage(t, r); |
| } while_each_thread(p, t); |
| break; |
| |
| default: |
| BUG(); |
| } |
| unlock_task_sighand(p, &flags); |
| |
| out: |
| r->ru_utime = ns_to_kernel_old_timeval(utime); |
| r->ru_stime = ns_to_kernel_old_timeval(stime); |
| |
| if (who != RUSAGE_CHILDREN) { |
| struct mm_struct *mm = get_task_mm(p); |
| |
| if (mm) { |
| setmax_mm_hiwater_rss(&maxrss, mm); |
| mmput(mm); |
| } |
| } |
| r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ |
| } |
| |
| SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
| { |
| struct rusage r; |
| |
| if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
| who != RUSAGE_THREAD) |
| return -EINVAL; |
| |
| getrusage(current, who, &r); |
| return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru) |
| { |
| struct rusage r; |
| |
| if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
| who != RUSAGE_THREAD) |
| return -EINVAL; |
| |
| getrusage(current, who, &r); |
| return put_compat_rusage(&r, ru); |
| } |
| #endif |
| |
| SYSCALL_DEFINE1(umask, int, mask) |
| { |
| mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); |
| return mask; |
| } |
| |
| static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) |
| { |
| struct fd exe; |
| struct inode *inode; |
| int err; |
| |
| exe = fdget(fd); |
| if (!exe.file) |
| return -EBADF; |
| |
| inode = file_inode(exe.file); |
| |
| /* |
| * Because the original mm->exe_file points to executable file, make |
| * sure that this one is executable as well, to avoid breaking an |
| * overall picture. |
| */ |
| err = -EACCES; |
| if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path)) |
| goto exit; |
| |
| err = file_permission(exe.file, MAY_EXEC); |
| if (err) |
| goto exit; |
| |
| err = replace_mm_exe_file(mm, exe.file); |
| exit: |
| fdput(exe); |
| return err; |
| } |
| |
| /* |
| * Check arithmetic relations of passed addresses. |
| * |
| * WARNING: we don't require any capability here so be very careful |
| * in what is allowed for modification from userspace. |
| */ |
| static int validate_prctl_map_addr(struct prctl_mm_map *prctl_map) |
| { |
| unsigned long mmap_max_addr = TASK_SIZE; |
| int error = -EINVAL, i; |
| |
| static const unsigned char offsets[] = { |
| offsetof(struct prctl_mm_map, start_code), |
| offsetof(struct prctl_mm_map, end_code), |
| offsetof(struct prctl_mm_map, start_data), |
| offsetof(struct prctl_mm_map, end_data), |
| offsetof(struct prctl_mm_map, start_brk), |
| offsetof(struct prctl_mm_map, brk), |
| offsetof(struct prctl_mm_map, start_stack), |
| offsetof(struct prctl_mm_map, arg_start), |
| offsetof(struct prctl_mm_map, arg_end), |
| offsetof(struct prctl_mm_map, env_start), |
| offsetof(struct prctl_mm_map, env_end), |
| }; |
| |
| /* |
| * Make sure the members are not somewhere outside |
| * of allowed address space. |
| */ |
| for (i = 0; i < ARRAY_SIZE(offsets); i++) { |
| u64 val = *(u64 *)((char *)prctl_map + offsets[i]); |
| |
| if ((unsigned long)val >= mmap_max_addr || |
| (unsigned long)val < mmap_min_addr) |
| goto out; |
| } |
| |
| /* |
| * Make sure the pairs are ordered. |
| */ |
| #define __prctl_check_order(__m1, __op, __m2) \ |
| ((unsigned long)prctl_map->__m1 __op \ |
| (unsigned long)prctl_map->__m2) ? 0 : -EINVAL |
| error = __prctl_check_order(start_code, <, end_code); |
| error |= __prctl_check_order(start_data,<=, end_data); |
| error |= __prctl_check_order(start_brk, <=, brk); |
| error |= __prctl_check_order(arg_start, <=, arg_end); |
| error |= __prctl_check_order(env_start, <=, env_end); |
| if (error) |
| goto out; |
| #undef __prctl_check_order |
| |
| error = -EINVAL; |
| |
| /* |
| * Neither we should allow to override limits if they set. |
| */ |
| if (check_data_rlimit(rlimit(RLIMIT_DATA), prctl_map->brk, |
| prctl_map->start_brk, prctl_map->end_data, |
| prctl_map->start_data)) |
| goto out; |
| |
| error = 0; |
| out: |
| return error; |
| } |
| |
| #ifdef CONFIG_CHECKPOINT_RESTORE |
| static int prctl_set_mm_map(int opt, const void __user *addr, unsigned long data_size) |
| { |
| struct prctl_mm_map prctl_map = { .exe_fd = (u32)-1, }; |
| unsigned long user_auxv[AT_VECTOR_SIZE]; |
| struct mm_struct *mm = current->mm; |
| int error; |
| |
| BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); |
| BUILD_BUG_ON(sizeof(struct prctl_mm_map) > 256); |
| |
| if (opt == PR_SET_MM_MAP_SIZE) |
| return put_user((unsigned int)sizeof(prctl_map), |
| (unsigned int __user *)addr); |
| |
| if (data_size != sizeof(prctl_map)) |
| return -EINVAL; |
| |
| if (copy_from_user(&prctl_map, addr, sizeof(prctl_map))) |
| return -EFAULT; |
| |
| error = validate_prctl_map_addr(&prctl_map); |
| if (error) |
| return error; |
| |
| if (prctl_map.auxv_size) { |
| /* |
| * Someone is trying to cheat the auxv vector. |
| */ |
| if (!prctl_map.auxv || |
| prctl_map.auxv_size > sizeof(mm->saved_auxv)) |
| return -EINVAL; |
| |
| memset(user_auxv, 0, sizeof(user_auxv)); |
| if (copy_from_user(user_auxv, |
| (const void __user *)prctl_map.auxv, |
| prctl_map.auxv_size)) |
| return -EFAULT; |
| |
| /* Last entry must be AT_NULL as specification requires */ |
| user_auxv[AT_VECTOR_SIZE - 2] = AT_NULL; |
| user_auxv[AT_VECTOR_SIZE - 1] = AT_NULL; |
| } |
| |
| if (prctl_map.exe_fd != (u32)-1) { |
| /* |
| * Check if the current user is checkpoint/restore capable. |
| * At the time of this writing, it checks for CAP_SYS_ADMIN |
| * or CAP_CHECKPOINT_RESTORE. |
| * Note that a user with access to ptrace can masquerade an |
| * arbitrary program as any executable, even setuid ones. |
| * This may have implications in the tomoyo subsystem. |
| */ |
| if (!checkpoint_restore_ns_capable(current_user_ns())) |
| return -EPERM; |
| |
| error = prctl_set_mm_exe_file(mm, prctl_map.exe_fd); |
| if (error) |
| return error; |
| } |
| |
| /* |
| * arg_lock protects concurrent updates but we still need mmap_lock for |
| * read to exclude races with sys_brk. |
| */ |
| mmap_read_lock(mm); |
| |
| /* |
| * We don't validate if these members are pointing to |
| * real present VMAs because application may have correspond |
| * VMAs already unmapped and kernel uses these members for statistics |
| * output in procfs mostly, except |
| * |
| * - @start_brk/@brk which are used in do_brk_flags but kernel lookups |
| * for VMAs when updating these members so anything wrong written |
| * here cause kernel to swear at userspace program but won't lead |
| * to any problem in kernel itself |
| */ |
| |
| spin_lock(&mm->arg_lock); |
| mm->start_code = prctl_map.start_code; |
| mm->end_code = prctl_map.end_code; |
| mm->start_data = prctl_map.start_data; |
| mm->end_data = prctl_map.end_data; |
| mm->start_brk = prctl_map.start_brk; |
| mm->brk = prctl_map.brk; |
| mm->start_stack = prctl_map.start_stack; |
| mm->arg_start = prctl_map.arg_start; |
| mm->arg_end = prctl_map.arg_end; |
| mm->env_start = prctl_map.env_start; |
| mm->env_end = prctl_map.env_end; |
| spin_unlock(&mm->arg_lock); |
| |
| /* |
| * Note this update of @saved_auxv is lockless thus |
| * if someone reads this member in procfs while we're |
| * updating -- it may get partly updated results. It's |
| * known and acceptable trade off: we leave it as is to |
| * not introduce additional locks here making the kernel |
| * more complex. |
| */ |
| if (prctl_map.auxv_size) |
| memcpy(mm->saved_auxv, user_auxv, sizeof(user_auxv)); |
| |
| mmap_read_unlock(mm); |
| return 0; |
| } |
| #endif /* CONFIG_CHECKPOINT_RESTORE */ |
| |
| static int prctl_set_auxv(struct mm_struct *mm, unsigned long addr, |
| unsigned long len) |
| { |
| /* |
| * This doesn't move the auxiliary vector itself since it's pinned to |
| * mm_struct, but it permits filling the vector with new values. It's |
| * up to the caller to provide sane values here, otherwise userspace |
| * tools which use this vector might be unhappy. |
| */ |
| unsigned long user_auxv[AT_VECTOR_SIZE] = {}; |
| |
| if (len > sizeof(user_auxv)) |
| return -EINVAL; |
| |
| if (copy_from_user(user_auxv, (const void __user *)addr, len)) |
| return -EFAULT; |
| |
| /* Make sure the last entry is always AT_NULL */ |
| user_auxv[AT_VECTOR_SIZE - 2] = 0; |
| user_auxv[AT_VECTOR_SIZE - 1] = 0; |
| |
| BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); |
| |
| task_lock(current); |
| memcpy(mm->saved_auxv, user_auxv, len); |
| task_unlock(current); |
| |
| return 0; |
| } |
| |
| static int prctl_set_mm(int opt, unsigned long addr, |
| unsigned long arg4, unsigned long arg5) |
| { |
| struct mm_struct *mm = current->mm; |
| struct prctl_mm_map prctl_map = { |
| .auxv = NULL, |
| .auxv_size = 0, |
| .exe_fd = -1, |
| }; |
| struct vm_area_struct *vma; |
| int error; |
| |
| if (arg5 || (arg4 && (opt != PR_SET_MM_AUXV && |
| opt != PR_SET_MM_MAP && |
| opt != PR_SET_MM_MAP_SIZE))) |
| return -EINVAL; |
| |
| #ifdef CONFIG_CHECKPOINT_RESTORE |
| if (opt == PR_SET_MM_MAP || opt == PR_SET_MM_MAP_SIZE) |
| return prctl_set_mm_map(opt, (const void __user *)addr, arg4); |
| #endif |
| |
| if (!capable(CAP_SYS_RESOURCE)) |
| return -EPERM; |
| |
| if (opt == PR_SET_MM_EXE_FILE) |
| return prctl_set_mm_exe_file(mm, (unsigned int)addr); |
| |
| if (opt == PR_SET_MM_AUXV) |
| return prctl_set_auxv(mm, addr, arg4); |
| |
| if (addr >= TASK_SIZE || addr < mmap_min_addr) |
| return -EINVAL; |
| |
| error = -EINVAL; |
| |
| /* |
| * arg_lock protects concurrent updates of arg boundaries, we need |
| * mmap_lock for a) concurrent sys_brk, b) finding VMA for addr |
| * validation. |
| */ |
| mmap_read_lock(mm); |
| vma = find_vma(mm, addr); |
| |
| spin_lock(&mm->arg_lock); |
| prctl_map.start_code = mm->start_code; |
| prctl_map.end_code = mm->end_code; |
| prctl_map.start_data = mm->start_data; |
| prctl_map.end_data = mm->end_data; |
| prctl_map.start_brk = mm->start_brk; |
| prctl_map.brk = mm->brk; |
| prctl_map.start_stack = mm->start_stack; |
| prctl_map.arg_start = mm->arg_start; |
| prctl_map.arg_end = mm->arg_end; |
| prctl_map.env_start = mm->env_start; |
| prctl_map.env_end = mm->env_end; |
| |
| switch (opt) { |
| case PR_SET_MM_START_CODE: |
| prctl_map.start_code = addr; |
| break; |
| case PR_SET_MM_END_CODE: |
| prctl_map.end_code = addr; |
| break; |
| case PR_SET_MM_START_DATA: |
| prctl_map.start_data = addr; |
| break; |
| case PR_SET_MM_END_DATA: |
| prctl_map.end_data = addr; |
| break; |
| case PR_SET_MM_START_STACK: |
| prctl_map.start_stack = addr; |
| break; |
| case PR_SET_MM_START_BRK: |
| prctl_map.start_brk = addr; |
| break; |
| case PR_SET_MM_BRK: |
| prctl_map.brk = addr; |
| break; |
| case PR_SET_MM_ARG_START: |
| prctl_map.arg_start = addr; |
| break; |
| case PR_SET_MM_ARG_END: |
| prctl_map.arg_end = addr; |
| break; |
| case PR_SET_MM_ENV_START: |
| prctl_map.env_start = addr; |
| break; |
| case PR_SET_MM_ENV_END: |
| prctl_map.env_end = addr; |
| break; |
| default: |
| goto out; |
| } |
| |
| error = validate_prctl_map_addr(&prctl_map); |
| if (error) |
| goto out; |
| |
| switch (opt) { |
| /* |
| * If command line arguments and environment |
| * are placed somewhere else on stack, we can |
| * set them up here, ARG_START/END to setup |
| * command line arguments and ENV_START/END |
| * for environment. |
| */ |
| case PR_SET_MM_START_STACK: |
| case PR_SET_MM_ARG_START: |
| case PR_SET_MM_ARG_END: |
| case PR_SET_MM_ENV_START: |
| case PR_SET_MM_ENV_END: |
| if (!vma) { |
| error = -EFAULT; |
| goto out; |
| } |
| } |
| |
| mm->start_code = prctl_map.start_code; |
| mm->end_code = prctl_map.end_code; |
| mm->start_data = prctl_map.start_data; |
| mm->end_data = prctl_map.end_data; |
| mm->start_brk = prctl_map.start_brk; |
| mm->brk = prctl_map.brk; |
| mm->start_stack = prctl_map.start_stack; |
| mm->arg_start = prctl_map.arg_start; |
| mm->arg_end = prctl_map.arg_end; |
| mm->env_start = prctl_map.env_start; |
| mm->env_end = prctl_map.env_end; |
| |
| error = 0; |
| out: |
| spin_unlock(&mm->arg_lock); |
| mmap_read_unlock(mm); |
| return error; |
| } |
| |
| #ifdef CONFIG_CHECKPOINT_RESTORE |
| static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr) |
| { |
| return put_user(me->clear_child_tid, tid_addr); |
| } |
| #else |
| static int prctl_get_tid_address(struct task_struct *me, int __user * __user *tid_addr) |
| { |
| return -EINVAL; |
| } |
| #endif |
| |
| static int propagate_has_child_subreaper(struct task_struct *p, void *data) |
| { |
| /* |
| * If task has has_child_subreaper - all its descendants |
| * already have these flag too and new descendants will |
| * inherit it on fork, skip them. |
| * |
| * If we've found child_reaper - skip descendants in |
| * it's subtree as they will never get out pidns. |
| */ |
| if (p->signal->has_child_subreaper || |
| is_child_reaper(task_pid(p))) |
| return 0; |
| |
| p->signal->has_child_subreaper = 1; |
| return 1; |
| } |
| |
| int __weak arch_prctl_spec_ctrl_get(struct task_struct *t, unsigned long which) |
| { |
| return -EINVAL; |
| } |
| |
| int __weak arch_prctl_spec_ctrl_set(struct task_struct *t, unsigned long which, |
| unsigned long ctrl) |
| { |
| return -EINVAL; |
| } |
| |
| #define PR_IO_FLUSHER (PF_MEMALLOC_NOIO | PF_LOCAL_THROTTLE) |
| |
| #ifdef CONFIG_ANON_VMA_NAME |
| |
| #define ANON_VMA_NAME_MAX_LEN 256 |
| #define ANON_VMA_NAME_INVALID_CHARS "\\`$[]" |
| |
| static inline bool is_valid_name_char(char ch) |
| { |
| /* printable ascii characters, excluding ANON_VMA_NAME_INVALID_CHARS */ |
| return ch > 0x1f && ch < 0x7f && |
| !strchr(ANON_VMA_NAME_INVALID_CHARS, ch); |
| } |
| |
| static int prctl_set_vma(unsigned long opt, unsigned long addr, |
| unsigned long size, unsigned long arg) |
| { |
| struct mm_struct *mm = current->mm; |
| const char __user *uname; |
| struct anon_vma_name *anon_name = NULL; |
| int error; |
| |
| switch (opt) { |
| case PR_SET_VMA_ANON_NAME: |
| uname = (const char __user *)arg; |
| if (uname) { |
| char *name, *pch; |
| |
| name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN); |
| if (IS_ERR(name)) |
| return PTR_ERR(name); |
| |
| for (pch = name; *pch != '\0'; pch++) { |
| if (!is_valid_name_char(*pch)) { |
| kfree(name); |
| return -EINVAL; |
| } |
| } |
| /* anon_vma has its own copy */ |
| anon_name = anon_vma_name_alloc(name); |
| kfree(name); |
| if (!anon_name) |
| return -ENOMEM; |
| |
| } |
| |
| mmap_write_lock(mm); |
| error = madvise_set_anon_name(mm, addr, size, anon_name); |
| mmap_write_unlock(mm); |
| anon_vma_name_put(anon_name); |
| break; |
| default: |
| error = -EINVAL; |
| } |
| |
| return error; |
| } |
| |
| #else /* CONFIG_ANON_VMA_NAME */ |
| static int prctl_set_vma(unsigned long opt, unsigned long start, |
| unsigned long size, unsigned long arg) |
| { |
| return -EINVAL; |
| } |
| #endif /* CONFIG_ANON_VMA_NAME */ |
| |
| SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
| unsigned long, arg4, unsigned long, arg5) |
| { |
| struct task_struct *me = current; |
| unsigned char comm[sizeof(me->comm)]; |
| long error; |
| |
| error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
| if (error != -ENOSYS) |
| return error; |
| |
| error = 0; |
| switch (option) { |
| case PR_SET_PDEATHSIG: |
| if (!valid_signal(arg2)) { |
| error = -EINVAL; |
| break; |
| } |
| me->pdeath_signal = arg2; |
| break; |
| case PR_GET_PDEATHSIG: |
| error = put_user(me->pdeath_signal, (int __user *)arg2); |
| break; |
| case PR_GET_DUMPABLE: |
| error = get_dumpable(me->mm); |
| break; |
| case PR_SET_DUMPABLE: |
| if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { |
| error = -EINVAL; |
| break; |
| } |
| set_dumpable(me->mm, arg2); |
| break; |
| |
| case PR_SET_UNALIGN: |
| error = SET_UNALIGN_CTL(me, arg2); |
| break; |
| case PR_GET_UNALIGN: |
| error = GET_UNALIGN_CTL(me, arg2); |
| break; |
| case PR_SET_FPEMU: |
| error = SET_FPEMU_CTL(me, arg2); |
| break; |
| case PR_GET_FPEMU: |
| error = GET_FPEMU_CTL(me, arg2); |
| break; |
| case PR_SET_FPEXC: |
| error = SET_FPEXC_CTL(me, arg2); |
| break; |
| case PR_GET_FPEXC: |
| error = GET_FPEXC_CTL(me, arg2); |
| break; |
| case PR_GET_TIMING: |
| error = PR_TIMING_STATISTICAL; |
| break; |
| case PR_SET_TIMING: |
| if (arg2 != PR_TIMING_STATISTICAL) |
| error = -EINVAL; |
| break; |
| case PR_SET_NAME: |
| comm[sizeof(me->comm) - 1] = 0; |
| if (strncpy_from_user(comm, (char __user *)arg2, |
| sizeof(me->comm) - 1) < 0) |
| return -EFAULT; |
| set_task_comm(me, comm); |
| proc_comm_connector(me); |
| break; |
| case PR_GET_NAME: |
| get_task_comm(comm, me); |
| if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) |
| return -EFAULT; |
| break; |
| case PR_GET_ENDIAN: |
| error = GET_ENDIAN(me, arg2); |
| break; |
| case PR_SET_ENDIAN: |
| error = SET_ENDIAN(me, arg2); |
| break; |
| case PR_GET_SECCOMP: |
| error = prctl_get_seccomp(); |
| break; |
| case PR_SET_SECCOMP: |
| error = prctl_set_seccomp(arg2, (char __user *)arg3); |
| break; |
| case PR_GET_TSC: |
| error = GET_TSC_CTL(arg2); |
| break; |
| case PR_SET_TSC: |
| error = SET_TSC_CTL(arg2); |
| break; |
| case PR_TASK_PERF_EVENTS_DISABLE: |
| error = perf_event_task_disable(); |
| break; |
| case PR_TASK_PERF_EVENTS_ENABLE: |
| error = perf_event_task_enable(); |
| break; |
| case PR_GET_TIMERSLACK: |
| if (current->timer_slack_ns > ULONG_MAX) |
| error = ULONG_MAX; |
| else |
| error = current->timer_slack_ns; |
| break; |
| case PR_SET_TIMERSLACK: |
| if (arg2 <= 0) |
| current->timer_slack_ns = |
| current->default_timer_slack_ns; |
| else |
| current->timer_slack_ns = arg2; |
| break; |
| case PR_MCE_KILL: |
| if (arg4 | arg5) |
| return -EINVAL; |
| switch (arg2) { |
| case PR_MCE_KILL_CLEAR: |
| if (arg3 != 0) |
| return -EINVAL; |
| current->flags &= ~PF_MCE_PROCESS; |
| break; |
| case PR_MCE_KILL_SET: |
| current->flags |= PF_MCE_PROCESS; |
| if (arg3 == PR_MCE_KILL_EARLY) |
| current->flags |= PF_MCE_EARLY; |
| else if (arg3 == PR_MCE_KILL_LATE) |
| current->flags &= ~PF_MCE_EARLY; |
| else if (arg3 == PR_MCE_KILL_DEFAULT) |
| current->flags &= |
| ~(PF_MCE_EARLY|PF_MCE_PROCESS); |
| else |
| return -EINVAL; |
| break; |
| default: |
| return -EINVAL; |
| } |
| break; |
| case PR_MCE_KILL_GET: |
| if (arg2 | arg3 | arg4 | arg5) |
| return -EINVAL; |
| if (current->flags & PF_MCE_PROCESS) |
| error = (current->flags & PF_MCE_EARLY) ? |
| PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; |
| else |
| error = PR_MCE_KILL_DEFAULT; |
| break; |
| case PR_SET_MM: |
| error = prctl_set_mm(arg2, arg3, arg4, arg5); |
| break; |
| case PR_GET_TID_ADDRESS: |
| error = prctl_get_tid_address(me, (int __user * __user *)arg2); |
| break; |
| case PR_SET_CHILD_SUBREAPER: |
| me->signal->is_child_subreaper = !!arg2; |
| if (!arg2) |
| break; |
| |
| walk_process_tree(me, propagate_has_child_subreaper, NULL); |
| break; |
| case PR_GET_CHILD_SUBREAPER: |
| error = put_user(me->signal->is_child_subreaper, |
| (int __user *)arg2); |
| break; |
| case PR_SET_NO_NEW_PRIVS: |
| if (arg2 != 1 || arg3 || arg4 || arg5) |
| return -EINVAL; |
| |
| task_set_no_new_privs(current); |
| break; |
| case PR_GET_NO_NEW_PRIVS: |
| if (arg2 || arg3 || arg4 || arg5) |
| return -EINVAL; |
| return task_no_new_privs(current) ? 1 : 0; |
| case PR_GET_THP_DISABLE: |
| if (arg2 || arg3 || arg4 || arg5) |
| return -EINVAL; |
| error = !!test_bit(MMF_DISABLE_THP, &me->mm->flags); |
| break; |
| case PR_SET_THP_DISABLE: |
| if (arg3 || arg4 || arg5) |
| return -EINVAL; |
| if (mmap_write_lock_killable(me->mm)) |
| return -EINTR; |
| if (arg2) |
| set_bit(MMF_DISABLE_THP, &me->mm->flags); |
| else |
| clear_bit(MMF_DISABLE_THP, &me->mm->flags); |
| mmap_write_unlock(me->mm); |
| break; |
| case PR_MPX_ENABLE_MANAGEMENT: |
| case PR_MPX_DISABLE_MANAGEMENT: |
| /* No longer implemented: */ |
| return -EINVAL; |
| case PR_SET_FP_MODE: |
| error = SET_FP_MODE(me, arg2); |
| break; |
| case PR_GET_FP_MODE: |
| error = GET_FP_MODE(me); |
| break; |
| case PR_SVE_SET_VL: |
| error = SVE_SET_VL(arg2); |
| break; |
| case PR_SVE_GET_VL: |
| error = SVE_GET_VL(); |
| break; |
| case PR_GET_SPECULATION_CTRL: |
| if (arg3 || arg4 || arg5) |
| return -EINVAL; |
| error = arch_prctl_spec_ctrl_get(me, arg2); |
| break; |
| case PR_SET_SPECULATION_CTRL: |
| if (arg4 || arg5) |
| return -EINVAL; |
| error = arch_prctl_spec_ctrl_set(me, arg2, arg3); |
| break; |
| case PR_PAC_RESET_KEYS: |
| if (arg3 || arg4 || arg5) |
| return -EINVAL; |
| error = PAC_RESET_KEYS(me, arg2); |
| break; |
| case PR_PAC_SET_ENABLED_KEYS: |
| if (arg4 || arg5) |
| return -EINVAL; |
| error = PAC_SET_ENABLED_KEYS(me, arg2, arg3); |
| break; |
| case PR_PAC_GET_ENABLED_KEYS: |
| if (arg2 || arg3 || arg4 || arg5) |
| return -EINVAL; |
| error = PAC_GET_ENABLED_KEYS(me); |
| break; |
| case PR_SET_TAGGED_ADDR_CTRL: |
| if (arg3 || arg4 || arg5) |
| return -EINVAL; |
| error = SET_TAGGED_ADDR_CTRL(arg2); |
| break; |
| case PR_GET_TAGGED_ADDR_CTRL: |
| if (arg2 || arg3 || arg4 || arg5) |
| return -EINVAL; |
| error = GET_TAGGED_ADDR_CTRL(); |
| break; |
| case PR_SET_IO_FLUSHER: |
| if (!capable(CAP_SYS_RESOURCE)) |
| return -EPERM; |
| |
| if (arg3 || arg4 || arg5) |
| return -EINVAL; |
| |
| if (arg2 == 1) |
| current->flags |= PR_IO_FLUSHER; |
| else if (!arg2) |
| current->flags &= ~PR_IO_FLUSHER; |
| else |
| return -EINVAL; |
| break; |
| case PR_GET_IO_FLUSHER: |
| if (!capable(CAP_SYS_RESOURCE)) |
| return -EPERM; |
| |
| if (arg2 || arg3 || arg4 || arg5) |
| return -EINVAL; |
| |
| error = (current->flags & PR_IO_FLUSHER) == PR_IO_FLUSHER; |
| break; |
| case PR_SET_SYSCALL_USER_DISPATCH: |
| error = set_syscall_user_dispatch(arg2, arg3, arg4, |
| (char __user *) arg5); |
| break; |
| #ifdef CONFIG_SCHED_CORE |
| case PR_SCHED_CORE: |
| error = sched_core_share_pid(arg2, arg3, arg4, arg5); |
| break; |
| #endif |
| case PR_SET_VMA: |
| error = prctl_set_vma(arg2, arg3, arg4, arg5); |
| break; |
| default: |
| error = -EINVAL; |
| break; |
| } |
| trace_android_vh_syscall_prctl_finished(option, me); |
| return error; |
| } |
| |
| SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
| struct getcpu_cache __user *, unused) |
| { |
| int err = 0; |
| int cpu = raw_smp_processor_id(); |
| |
| if (cpup) |
| err |= put_user(cpu, cpup); |
| if (nodep) |
| err |= put_user(cpu_to_node(cpu), nodep); |
| return err ? -EFAULT : 0; |
| } |
| |
| /** |
| * do_sysinfo - fill in sysinfo struct |
| * @info: pointer to buffer to fill |
| */ |
| static int do_sysinfo(struct sysinfo *info) |
| { |
| unsigned long mem_total, sav_total; |
| unsigned int mem_unit, bitcount; |
| struct timespec64 tp; |
| |
| memset(info, 0, sizeof(struct sysinfo)); |
| |
| ktime_get_boottime_ts64(&tp); |
| timens_add_boottime(&tp); |
| info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); |
| |
| get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT); |
| |
| info->procs = nr_threads; |
| |
| si_meminfo(info); |
| si_swapinfo(info); |
| |
| /* |
| * If the sum of all the available memory (i.e. ram + swap) |
| * is less than can be stored in a 32 bit unsigned long then |
| * we can be binary compatible with 2.2.x kernels. If not, |
| * well, in that case 2.2.x was broken anyways... |
| * |
| * -Erik Andersen <andersee@debian.org> |
| */ |
| |
| mem_total = info->totalram + info->totalswap; |
| if (mem_total < info->totalram || mem_total < info->totalswap) |
| goto out; |
| bitcount = 0; |
| mem_unit = info->mem_unit; |
| while (mem_unit > 1) { |
| bitcount++; |
| mem_unit >>= 1; |
| sav_total = mem_total; |
| mem_total <<= 1; |
| if (mem_total < sav_total) |
| goto out; |
| } |
| |
| /* |
| * If mem_total did not overflow, multiply all memory values by |
| * info->mem_unit and set it to 1. This leaves things compatible |
| * with 2.2.x, and also retains compatibility with earlier 2.4.x |
| * kernels... |
| */ |
| |
| info->mem_unit = 1; |
| info->totalram <<= bitcount; |
| info->freeram <<= bitcount; |
| info->sharedram <<= bitcount; |
| info->bufferram <<= bitcount; |
| info->totalswap <<= bitcount; |
| info->freeswap <<= bitcount; |
| info->totalhigh <<= bitcount; |
| info->freehigh <<= bitcount; |
| |
| out: |
| return 0; |
| } |
| |
| SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) |
| { |
| struct sysinfo val; |
| |
| do_sysinfo(&val); |
| |
| if (copy_to_user(info, &val, sizeof(struct sysinfo))) |
| return -EFAULT; |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| struct compat_sysinfo { |
| s32 uptime; |
| u32 loads[3]; |
| u32 totalram; |
| u32 freeram; |
| u32 sharedram; |
| u32 bufferram; |
| u32 totalswap; |
| u32 freeswap; |
| u16 procs; |
| u16 pad; |
| u32 totalhigh; |
| u32 freehigh; |
| u32 mem_unit; |
| char _f[20-2*sizeof(u32)-sizeof(int)]; |
| }; |
| |
| COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) |
| { |
| struct sysinfo s; |
| struct compat_sysinfo s_32; |
| |
| do_sysinfo(&s); |
| |
| /* Check to see if any memory value is too large for 32-bit and scale |
| * down if needed |
| */ |
| if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) { |
| int bitcount = 0; |
| |
| while (s.mem_unit < PAGE_SIZE) { |
| s.mem_unit <<= 1; |
| bitcount++; |
| } |
| |
| s.totalram >>= bitcount; |
| s.freeram >>= bitcount; |
| s.sharedram >>= bitcount; |
| s.bufferram >>= bitcount; |
| s.totalswap >>= bitcount; |
| s.freeswap >>= bitcount; |
| s.totalhigh >>= bitcount; |
| s.freehigh >>= bitcount; |
| } |
| |
| memset(&s_32, 0, sizeof(s_32)); |
| s_32.uptime = s.uptime; |
| s_32.loads[0] = s.loads[0]; |
| s_32.loads[1] = s.loads[1]; |
| s_32.loads[2] = s.loads[2]; |
| s_32.totalram = s.totalram; |
| s_32.freeram = s.freeram; |
| s_32.sharedram = s.sharedram; |
| s_32.bufferram = s.bufferram; |
| s_32.totalswap = s.totalswap; |
| s_32.freeswap = s.freeswap; |
| s_32.procs = s.procs; |
| s_32.totalhigh = s.totalhigh; |
| s_32.freehigh = s.freehigh; |
| s_32.mem_unit = s.mem_unit; |
| if (copy_to_user(info, &s_32, sizeof(s_32))) |
| return -EFAULT; |
| return 0; |
| } |
| #endif /* CONFIG_COMPAT */ |