This is a note to let you know that I've just added the patch titled
futex: Fix futex_waitv() hrtimer debug object leak on kcalloc error
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
futex-fix-futex_waitv-hrtimer-debug-object-leak-on-kcalloc-error.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 94cd8fa09f5f1ebdd4e90964b08b7f2cc4b36c43 Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Date: Wed, 14 Dec 2022 17:20:08 -0500
Subject: futex: Fix futex_waitv() hrtimer debug object leak on kcalloc error
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;
}
Patches currently in stable-queue which might be from mathieu.desnoyers@xxxxxxxxxxxx are
queue-6.0/futex-fix-futex_waitv-hrtimer-debug-object-leak-on-kcalloc-error.patch
queue-6.0/mm-mempolicy-fix-memory-leak-in-set_mempolicy_home_node-system-call.patch
