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| author | Peter Maydell <peter.maydell@linaro.org> | 2019-07-25 14:16:45 +0100 |
|---|---|---|
| committer | Laurent Vivier <laurent@vivier.eu> | 2019-07-26 19:24:33 +0200 |
| commit | 5bfce0b74fbd5d53089bb866919d685c47edad9e (patch) | |
| tree | 7b352053272100d776034988ef56d2241afba8db /linux-user/main.c | |
| parent | fff3159900d2b95613a9cb75fc3703e67a674729 (diff) | |
| download | qemu-5bfce0b74fbd5d53089bb866919d685c47edad9e.zip qemu-5bfce0b74fbd5d53089bb866919d685c47edad9e.tar.gz qemu-5bfce0b74fbd5d53089bb866919d685c47edad9e.tar.bz2 | |
linux-user: Make sigaltstack stacks per-thread
The alternate signal stack set up by the sigaltstack syscall is
supposed to be per-thread. We were incorrectly implementing it as
process-wide. This causes problems for guest binaries that rely on
this. Notably the Go runtime does, and so we were seeing crashes
caused by races where two guest threads might incorrectly both
execute on the same stack simultaneously.
Replace the global target_sigaltstack_used with a field
sigaltstack_used in the TaskState, and make all the references to the
old global instead get a pointer to the TaskState and use the field.
Fixes: https://bugs.launchpad.net/qemu/+bug/1696773
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20190725131645.19501-1-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Diffstat (limited to 'linux-user/main.c')
| -rw-r--r-- | linux-user/main.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/linux-user/main.c b/linux-user/main.c index a59ae94..8ffc525 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -180,6 +180,11 @@ void stop_all_tasks(void) void init_task_state(TaskState *ts) { ts->used = 1; + ts->sigaltstack_used = (struct target_sigaltstack) { + .ss_sp = 0, + .ss_size = 0, + .ss_flags = TARGET_SS_DISABLE, + }; } CPUArchState *cpu_copy(CPUArchState *env) |