upgrade the GDB to 13.1 version, hookpost-extended-remote will not work. GNU gdb (GDB) 14.0.50.20230320-git Copyright (C) 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-pc-linux-gnu". Type "show configuration" for configuration details. For bug reporting instructions, please see: <https://www.gnu.org/software/gdb/bugs/>. Find the GDB manual and other documentation resources online at: <http://www.gnu.org/software/gdb/documentation/>. For help, type "help". Type "apropos word" to search for commands related to "word". (gdb) define target hookpost-extended-remote Type commands for definition of "target hookpost-extended-remote". End with a line saying just "end". >echo hookpost-extended-remote\n >end (gdb) target extended-remote 127.0.0.1:2345 Remote debugging using 127.0.0.1:2345 please note here: after issue target extended-remote 127.0.0.1:2345, the "hookpost-extended-remote; string didnot echo. this issue exist on version 13.1 and later.
I can reproduce the bug and created a tentative fix, see https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=f48f80529710f7dc9a87c6821315b7a1fa66853e I'll run it through my CI and eventually submit.
The master branch has been updated by Jan Vrany <jv@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=b69378ced6a2db6adfbea9974a246a65d931bab2 commit b69378ced6a2db6adfbea9974a246a65d931bab2 Author: Jan Vrany <jan.vrany@labware.com> Date: Fri May 19 13:20:04 2023 +0100 gdb: fix post-hook execution for remote targets Commit b5661ff2 ("gdb: fix possible use-after-free when executing commands") attempted to fix possible use-after-free in case command redefines itself. Commit 37e5833d ("gdb: fix command lookup in execute_command ()") updated the previous fix to handle subcommands as well by using the original command string to lookup the command again after its execution. This fixed the test in gdb.base/define.exp but it turned out that it does not work (at least) for "target remote" and "target extended-remote". The problem is that the command buffer P passed to execute_command () gets overwritten in dont_repeat () while executing "target remote" command itself: #0 dont_repeat () at top.c:822 #1 0x000055555730982a in target_preopen (from_tty=1) at target.c:2483 #2 0x000055555711e911 in remote_target::open_1 (name=0x55555881c7fe ":1234", from_tty=1, extended_p=0) at remote.c:5946 #3 0x000055555711d577 in remote_target::open (name=0x55555881c7fe ":1234", from_tty=1) at remote.c:5272 #4 0x00005555573062f2 in open_target (args=0x55555881c7fe ":1234", from_tty=1, command=0x5555589d0490) at target.c:853 #5 0x0000555556ad22fa in cmd_func (cmd=0x5555589d0490, args=0x55555881c7fe ":1234", from_tty=1) at cli/cli-decode.c:2737 #6 0x00005555573487fd in execute_command (p=0x55555881c802 "4", from_tty=1) at top.c:688 Therefore the second call to lookup_cmd () at line 697 fails to find command because the original command string is gone. This commit addresses this particular problem by creating a *copy* of original command string for the sole purpose of using it after command execution to lookup the command again. It may not be the most efficient way but it's safer given that command buffer is shared and overwritten in hard-to-foresee situations. Tested on x86_64-linux. PR 30249 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30249 Approved-By: Tom Tromey <tom@tromey.com>
Could you "git cherry-pick -x" this to the gdb 13 branch?
Optimistically setting the target milestone.
The gdb-13-branch branch has been updated by Jan Vrany <jv@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=bcd95b84d3045aef8ec50c019d7d9d4d0d5f3817 commit bcd95b84d3045aef8ec50c019d7d9d4d0d5f3817 Author: Jan Vrany <jan.vrany@labware.com> Date: Fri May 19 13:20:04 2023 +0100 gdb: fix post-hook execution for remote targets Commit b5661ff2 ("gdb: fix possible use-after-free when executing commands") attempted to fix possible use-after-free in case command redefines itself. Commit 37e5833d ("gdb: fix command lookup in execute_command ()") updated the previous fix to handle subcommands as well by using the original command string to lookup the command again after its execution. This fixed the test in gdb.base/define.exp but it turned out that it does not work (at least) for "target remote" and "target extended-remote". The problem is that the command buffer P passed to execute_command () gets overwritten in dont_repeat () while executing "target remote" command itself: #0 dont_repeat () at top.c:822 #1 0x000055555730982a in target_preopen (from_tty=1) at target.c:2483 #2 0x000055555711e911 in remote_target::open_1 (name=0x55555881c7fe ":1234", from_tty=1, extended_p=0) at remote.c:5946 #3 0x000055555711d577 in remote_target::open (name=0x55555881c7fe ":1234", from_tty=1) at remote.c:5272 #4 0x00005555573062f2 in open_target (args=0x55555881c7fe ":1234", from_tty=1, command=0x5555589d0490) at target.c:853 #5 0x0000555556ad22fa in cmd_func (cmd=0x5555589d0490, args=0x55555881c7fe ":1234", from_tty=1) at cli/cli-decode.c:2737 #6 0x00005555573487fd in execute_command (p=0x55555881c802 "4", from_tty=1) at top.c:688 Therefore the second call to lookup_cmd () at line 697 fails to find command because the original command string is gone. This commit addresses this particular problem by creating a *copy* of original command string for the sole purpose of using it after command execution to lookup the command again. It may not be the most efficient way but it's safer given that command buffer is shared and overwritten in hard-to-foresee situations. Tested on x86_64-linux. PR 30249 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30249 Approved-By: Tom Tromey <tom@tromey.com> (cherry picked from commit b69378ced6a2db6adfbea9974a246a65d931bab2)
(In reply to Tom Tromey from comment #3) > Could you "git cherry-pick -x" this to the gdb 13 branch? I did that, run the test suite and pushed. Hope all is all right.
Looks great, going to close this.