This is a note to let you know that I've just added the patch titled sysctl: Fix data races in proc_dointvec_minmax(). to the 5.18-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: sysctl-fix-data-races-in-proc_dointvec_minmax.patch and it can be found in the queue-5.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 269aced08b4fb3a49c4ada45ebe1a5c80ca28bdb Author: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> Date: Wed Jul 6 16:39:54 2022 -0700 sysctl: Fix data races in proc_dointvec_minmax(). [ Upstream commit f613d86d014b6375a4085901de39406598121e35 ] A sysctl variable is accessed concurrently, and there is always a chance of data-race. So, all readers and writers need some basic protection to avoid load/store-tearing. This patch changes proc_dointvec_minmax() to use READ_ONCE() and WRITE_ONCE() internally to fix data-races on the sysctl side. For now, proc_dointvec_minmax() itself is tolerant to a data-race, but we still need to add annotations on the other subsystem's side. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 6c61e2992fed..22ebf3f5eefe 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -929,7 +929,7 @@ static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp, if ((param->min && *param->min > tmp) || (param->max && *param->max < tmp)) return -EINVAL; - *valp = tmp; + WRITE_ONCE(*valp, tmp); } return 0;