5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zichen Xie <zichenxie0106@xxxxxxxxx>
[ Upstream commit 4ce1f56a1eaced2523329bef800d004e30f2f76c ]
This was found by a static analyzer.
We should not forget the trailing zero after copy_from_user()
if we will further do some string operations, sscanf() in this
case. Adding a trailing zero will ensure that the function
performs properly.
Fixes: c6385c0b67c5 ("netdevsim: Allow reporting activity on nexthop buckets")
Signed-off-by: Zichen Xie <zichenxie0106@xxxxxxxxx>
Reviewed-by: Petr Machata <petrm@xxxxxxxxxx>
Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxx>
Link: https://patch.msgid.link/20241022171907.8606-1-zichenxie0106@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/netdevsim/fib.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/net/netdevsim/fib.c b/drivers/net/netdevsim/fib.c
index 14787d17f703f..b71414b3a1d40 100644
--- a/drivers/net/netdevsim/fib.c
+++ b/drivers/net/netdevsim/fib.c
@@ -1366,10 +1366,12 @@ static ssize_t nsim_nexthop_bucket_activity_write(struct file *file,
if (pos != 0)
return -EINVAL;
- if (size > sizeof(buf))
+ if (size > sizeof(buf) - 1)
return -EINVAL;
if (copy_from_user(buf, user_buf, size))
return -EFAULT;
+ buf[size] = 0;
+
if (sscanf(buf, "%u %hu", &nhid, &bucket_index) != 2)
return -EINVAL;
--
2.43.0
