On Mon, Dec 20, 2021 at 05:26:27PM +0800, Baokun Li wrote:

When we pass a negative value to the proc_doulongvec_minmax() function,
the function returns 0, but the corresponding interface value does not
change.

we can easily reproduce this problem with the following commands:
    `cd /proc/sys/fs/epoll`
    `echo -1 > max_user_watches; echo $?; cat max_user_watches`

This function requires a non-negative number to be passed in, so when
a negative number is passed in, -EINVAL is returned.

Reported-by: Hulk Robot <redacted>
Signed-off-by: Baokun Li <redacted>

Acked-by: Luis Chamberlain <mcgrof@kernel.org>

 Luis