Commit-ID: a9445e47d897054876b8f43e46dc5a3eca2b844d Gitweb: https://git.kernel.org/tip/a9445e47d897054876b8f43e46dc5a3eca2b844d Author: Max R. P. Grossmann <[email protected]> AuthorDate: Mon, 8 Jan 2018 20:01:57 +0100 Committer: Thomas Gleixner <[email protected]> CommitDate: Sun, 14 Jan 2018 20:50:59 +0100
posix-cpu-timers: Make set_process_cpu_timer() more robust Because the return value of cpu_timer_sample_group() is not checked, compilers and static checkers can legitimately warn about a potential use of the uninitialized variable 'now'. This is not a runtime issue as all call sites hand in valid clock ids. Also cpu_timer_sample_group() is invoked unconditionally even when the result is not used because *oldval is NULL. Make the invocation conditional and check the return value. [ tglx: Massage changelog ] Signed-off-by: Max R. P. Grossmann <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] --- kernel/time/posix-cpu-timers.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index cef79ca..ec9f5da 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -1189,9 +1189,8 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, u64 now; WARN_ON_ONCE(clock_idx == CPUCLOCK_SCHED); - cpu_timer_sample_group(clock_idx, tsk, &now); - if (oldval) { + if (oldval && cpu_timer_sample_group(clock_idx, tsk, &now) != -EINVAL) { /* * We are setting itimer. The *oldval is absolute and we update * it to be relative, *newval argument is relative and we update
