6.6-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ 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@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/675c6862.050a0220.37aaf.00b1.GAE@google.com/T... Signed-off-by: Eric Dumazet edumazet@google.com Cc: Jiri Pirko jiri@nvidia.com Reviewed-by: Joe Damato jdamato@fastly.com Link: https://patch.msgid.link/20241213172518.2415666-1-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/netdevsim/health.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/net/netdevsim/health.c b/drivers/net/netdevsim/health.c index eb04ed715d2d..c63427b71898 100644 --- a/drivers/net/netdevsim/health.c +++ b/drivers/net/netdevsim/health.c @@ -203,6 +203,8 @@ 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);