From dfe8c6516289fd21045e2f22eeb49e1fdf9845df Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Wed, 24 Mar 2021 14:42:20 +0000 Subject: [PATCH] netdevsim: switch to memdup_user_nul() [ Upstream commit 20fd4f421cf4c21ab37a8bf31db50c69f1b49355 ] Use memdup_user_nul() helper instead of open-coding to simplify the code. Reported-by: Hulk Robot Signed-off-by: Wei Yongjun Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller Stable-dep-of: ee76746387f6 ("netdevsim: prevent bad user input in nsim_dev_health_break_write()") Signed-off-by: Sasha Levin --- drivers/net/netdevsim/health.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/net/netdevsim/health.c b/drivers/net/netdevsim/health.c index 21e297466..04aebdf85 100755 --- a/drivers/net/netdevsim/health.c +++ b/drivers/net/netdevsim/health.c @@ -235,15 +235,10 @@ static ssize_t nsim_dev_health_break_write(struct file *file, char *break_msg; int err; - break_msg = kmalloc(count + 1, GFP_KERNEL); - if (!break_msg) - return -ENOMEM; + break_msg = memdup_user_nul(data, count); + if (IS_ERR(break_msg)) + return PTR_ERR(break_msg); - if (copy_from_user(break_msg, data, count)) { - err = -EFAULT; - goto out; - } - break_msg[count] = '\0'; if (break_msg[count - 1] == '\n') break_msg[count - 1] = '\0';