This is a note to let you know that I've just added the patch titled
netdevsim: prevent bad user input in nsim_dev_health_break_write()
to the 5.15-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:
netdevsim-prevent-bad-user-input-in-nsim_dev_health_.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 12b1661b6b4162c5ecbd69b9587e94d77b388f70
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Fri Dec 13 17:25:18 2024 +0000
netdevsim: prevent bad user input in nsim_dev_health_break_write()
[ Upstream commit ee76746387f6233bdfa93d7406990f923641568f ]
If either a zero count or a large one is provided, kernel can crash.
Fixes: 82c93a87bf8b ("netdevsim: implement couple of testing devlink health reporters")
Reported-by: syzbot+ea40e4294e58b0292f74@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://lore.kernel.org/netdev/675c6862.050a0220.37aaf.00b1.GAE@xxxxxxxxxx/T/#u
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Jiri Pirko <jiri@xxxxxxxxxx>
Reviewed-by: Joe Damato <jdamato@xxxxxxxxxx>
Link: https://patch.msgid.link/20241213172518.2415666-1-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/netdevsim/health.c b/drivers/net/netdevsim/health.c
index 04aebdf85747..c9306506b741 100644
--- a/drivers/net/netdevsim/health.c
+++ b/drivers/net/netdevsim/health.c
@@ -235,6 +235,8 @@ static ssize_t nsim_dev_health_break_write(struct file *file,
char *break_msg;
int err;
+ if (count == 0 || count > PAGE_SIZE)
+ return -EINVAL;
break_msg = memdup_user_nul(data, count);
if (IS_ERR(break_msg))
return PTR_ERR(break_msg);
