From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
commit 94cd8fa09f5f1ebdd4e90964b08b7f2cc4b36c43 upstream.
In a scenario where kcalloc() fails to allocate memory, the futex_waitv
system call immediately returns -ENOMEM without invoking
destroy_hrtimer_on_stack(). When CONFIG_DEBUG_OBJECTS_TIMERS=y, this
results in leaking a timer debug object.
Fixes: bf69bad38cf6 ("futex: Implement sys_futex_waitv()")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx # v5.16+
Link: https://lore.kernel.org/r/20221214222008.200393-1-mathieu.desnoyers@xxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/futex/syscalls.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
--- a/kernel/futex/syscalls.c
+++ b/kernel/futex/syscalls.c
@@ -286,19 +286,22 @@ SYSCALL_DEFINE5(futex_waitv, struct fute
}
futexv = kcalloc(nr_futexes, sizeof(*futexv), GFP_KERNEL);
- if (!futexv)
- return -ENOMEM;
+ if (!futexv) {
+ ret = -ENOMEM;
+ goto destroy_timer;
+ }
ret = futex_parse_waitv(futexv, waiters, nr_futexes);
if (!ret)
ret = futex_wait_multiple(futexv, nr_futexes, timeout ? &to : NULL);
+ kfree(futexv);
+
+destroy_timer:
if (timeout) {
hrtimer_cancel(&to.timer);
destroy_hrtimer_on_stack(&to.timer);
}
-
- kfree(futexv);
return ret;
}
