This is a note to let you know that I've just added the patch titled net/atm: fix proc_mpc_write incorrect return value to the 4.9-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: net-atm-fix-proc_mpc_write-incorrect-return-value.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3fbec01abd5c0178b56fa95345c48a72a01b3219 Author: Xiaobo Liu <cppcoffee@xxxxxxxxx> Date: Fri Oct 14 10:05:40 2022 +0800 net/atm: fix proc_mpc_write incorrect return value [ Upstream commit d8bde3bf7f82dac5fc68a62c2816793a12cafa2a ] Then the input contains '\0' or '\n', proc_mpc_write has read them, so the return value needs +1. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xiaobo Liu <cppcoffee@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/atm/mpoa_proc.c b/net/atm/mpoa_proc.c index 2df34eb5d65f..3fd2aafa9a9e 100644 --- a/net/atm/mpoa_proc.c +++ b/net/atm/mpoa_proc.c @@ -219,11 +219,12 @@ static ssize_t proc_mpc_write(struct file *file, const char __user *buff, if (!page) return -ENOMEM; - for (p = page, len = 0; len < nbytes; p++, len++) { + for (p = page, len = 0; len < nbytes; p++) { if (get_user(*p, buff++)) { free_page((unsigned long)page); return -EFAULT; } + len += 1; if (*p == '\0' || *p == '\n') break; }