This is a note to let you know that I've just added the patch titled
s390/cio: Ensure the copied buf is NUL terminated
to the 6.6-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:
s390-cio-ensure-the-copied-buf-is-nul-terminated.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 42a18988e7574afffc677edf167e7f5e32f45552
Author: Bui Quang Minh <minhquangbui99@xxxxxxxxx>
Date: Wed Apr 24 21:44:22 2024 +0700
s390/cio: Ensure the copied buf is NUL terminated
[ Upstream commit da7c622cddd4fe36be69ca61e8c42e43cde94784 ]
Currently, we allocate a lbuf-sized kernel buffer and copy lbuf from
userspace to that buffer. Later, we use scanf on this buffer but we don't
ensure that the string is terminated inside the buffer, this can lead to
OOB read when using scanf. Fix this issue by using memdup_user_nul instead.
Fixes: a4f17cc72671 ("s390/cio: add CRW inject functionality")
Signed-off-by: Bui Quang Minh <minhquangbui99@xxxxxxxxx>
Reviewed-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240424-fix-oob-read-v2-5-f1f1b53a10f4@xxxxxxxxx
Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/s390/cio/cio_inject.c b/drivers/s390/cio/cio_inject.c
index 8613fa937237b..a2e771ebae8eb 100644
--- a/drivers/s390/cio/cio_inject.c
+++ b/drivers/s390/cio/cio_inject.c
@@ -95,7 +95,7 @@ static ssize_t crw_inject_write(struct file *file, const char __user *buf,
return -EINVAL;
}
- buffer = vmemdup_user(buf, lbuf);
+ buffer = memdup_user_nul(buf, lbuf);
if (IS_ERR(buffer))
return -ENOMEM;
