| Message ID | 20211220092627.3744624-1-libaokun1@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [-next,V2] sysctl: returns -EINVAL when a negative value is passed to proc_doulongvec_minmax | expand |
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 <hulkci@huawei.com> > Signed-off-by: Baokun Li <libaokun1@huawei.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Luis
在 2021/12/21 3:17, Luis Chamberlain 写道: > 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 <hulkci@huawei.com> >> Signed-off-by: Baokun Li <libaokun1@huawei.com> > Acked-by: Luis Chamberlain <mcgrof@kernel.org> > > Luis > . Thank you for your Ack.
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 7f07b058b180..4211e39a5fd3 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1147,10 +1147,11 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, err = proc_get_long(&p, &left, &val, &neg, proc_wspace_sep, sizeof(proc_wspace_sep), NULL); - if (err) + if (err || neg) { + err = -EINVAL; break; - if (neg) - continue; + } + val = convmul * val / convdiv; if ((min && val < *min) || (max && val > *max)) { err = -EINVAL;
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 <hulkci@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> --- V1->V2: Modify the judgment position. kernel/sysctl.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)