From 00515ea3a15703a3d196c1d1bd372214abc990ad Mon Sep 17 00:00:00 2001 From: Alistair Francis Date: Mon, 6 Apr 2020 10:56:26 -0700 Subject: [PATCH] linux: wait4: Fix incorrect return value comparison Patch 600f00b "linux: Use long time_t for wait4/getrusage" introduced two bugs: - The usage32 struct was set if the wait4 syscall had an error. - For 32-bit systems the usage struct was set even if it was specified as NULL. This patch fixes the two issues. --- sysdeps/unix/sysv/linux/wait4.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/sysdeps/unix/sysv/linux/wait4.c b/sysdeps/unix/sysv/linux/wait4.c index d14bd4da27..44c55f60fe 100644 --- a/sysdeps/unix/sysv/linux/wait4.c +++ b/sysdeps/unix/sysv/linux/wait4.c @@ -29,13 +29,13 @@ __wait4_time64 (pid_t pid, int *stat_loc, int options, struct __rusage64 *usage) # if __KERNEL_OLD_TIMEVAL_MATCHES_TIMEVAL64 return SYSCALL_CANCEL (wait4, pid, stat_loc, options, usage); # else + pid_t ret; struct __rusage32 usage32; - pid_t ret = SYSCALL_CANCEL (wait4, pid, stat_loc, options, &usage32); - if (ret != 0) - return ret; + ret = SYSCALL_CANCEL (wait4, pid, stat_loc, options, + usage != NULL ? &usage32 : NULL); - if (usage != NULL) + if (ret > 0 && usage != NULL) rusage32_to_rusage64 (&usage32, usage); return ret; @@ -114,15 +114,14 @@ libc_hidden_def (__wait4_time64) pid_t __wait4 (pid_t pid, int *stat_loc, int options, struct rusage *usage) { - pid_t ret ; + pid_t ret; struct __rusage64 usage64; - ret = __wait4_time64 (pid, stat_loc, options, &usage64); + ret = __wait4_time64 (pid, stat_loc, options, + usage != NULL ? &usage64 : NULL); - if (ret != 0) - return ret; - - rusage64_to_rusage (&usage64, usage); + if (ret > 0 && usage != 0) + rusage64_to_rusage (&usage64, usage); return ret; }