diff options
| author | Matthias Schiffer <mschiffer@universe-factory.net> | 2021-10-23 21:59:10 +0200 |
|---|---|---|
| committer | Laurent Vivier <laurent@vivier.eu> | 2022-01-06 11:40:52 +0100 |
| commit | 139e5de7c883522b7307e26d4b7dce489b53e307 (patch) | |
| tree | c6e77ac68da2b832507db1e469602536b166b319 /linux-user | |
| parent | 4da06fb306276946e227669bfc4df2077a8fa6c9 (diff) | |
linux-user/signal: Map exit signals in SIGCHLD siginfo_t
When converting a siginfo_t from waitid(), the interpretation of si_status
depends on the value of si_code: For CLD_EXITED, it is an exit code and
should be copied verbatim. For other codes, it is a signal number
(possibly with additional high bits from ptrace) that should be mapped.
This code was previously changed in commit 1c3dfb506ea3
("linux-user/signal: Decode waitid si_code"), but the fix was
incomplete.
Tested with the following test program:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
int main() {
pid_t pid = fork();
if (pid == 0) {
exit(12);
} else {
siginfo_t siginfo = {};
waitid(P_PID, pid, &siginfo, WEXITED);
printf("Code: %d, status: %d\n", (int)siginfo.si_code, (int)siginfo.si_status);
}
pid = fork();
if (pid == 0) {
raise(SIGUSR2);
} else {
siginfo_t siginfo = {};
waitid(P_PID, pid, &siginfo, WEXITED);
printf("Code: %d, status: %d\n", (int)siginfo.si_code, (int)siginfo.si_status);
}
}
Output with an x86_64 host and mips64el target before 1c3dfb506ea3
(incorrect: exit code 12 is translated like a signal):
Code: 1, status: 17
Code: 2, status: 17
After 1c3dfb506ea3 (incorrect: signal number is not translated):
Code: 1, status: 12
Code: 2, status: 12
With this patch:
Code: 1, status: 12
Code: 2, status: 17
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <81534fde7cdfc6acea4889d886fbefdd606630fb.1635019124.git.mschiffer@universe-factory.net>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Diffstat (limited to 'linux-user')
| -rw-r--r-- | linux-user/signal.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/linux-user/signal.c b/linux-user/signal.c index 510db73c34..1229fecf5c 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -406,7 +406,12 @@ static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo, case TARGET_SIGCHLD: tinfo->_sifields._sigchld._pid = info->si_pid; tinfo->_sifields._sigchld._uid = info->si_uid; - tinfo->_sifields._sigchld._status = info->si_status; + if (si_code == CLD_EXITED) + tinfo->_sifields._sigchld._status = info->si_status; + else + tinfo->_sifields._sigchld._status + = host_to_target_signal(info->si_status & 0x7f) + | (info->si_status & ~0x7f); tinfo->_sifields._sigchld._utime = info->si_utime; tinfo->_sifields._sigchld._stime = info->si_stime; si_type = QEMU_SI_CHLD; |