This is a note to let you know that I've just added the patch titled
rsxx: Return -EFAULT if copy_to_user() fails
to the 4.4-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:
rsxx-return-efault-if-copy_to_user-fails.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5370357c0ec0a2af2f963b13c25e17976b8c87a2
Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Wed Mar 3 13:59:12 2021 +0300
rsxx: Return -EFAULT if copy_to_user() fails
[ Upstream commit 77516d25f54912a7baedeeac1b1b828b6f285152 ]
The copy_to_user() function returns the number of bytes remaining but
we want to return -EFAULT to the user if it can't complete the copy.
The "st" variable only holds zero on success or negative error codes on
failure so the type should be int.
Fixes: 36f988e978f8 ("rsxx: Adding in debugfs entries.")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/block/rsxx/core.c b/drivers/block/rsxx/core.c
index 620a3a67cdd5..0d9137408e3c 100644
--- a/drivers/block/rsxx/core.c
+++ b/drivers/block/rsxx/core.c
@@ -180,15 +180,17 @@ static ssize_t rsxx_cram_read(struct file *fp, char __user *ubuf,
{
struct rsxx_cardinfo *card = file_inode(fp)->i_private;
char *buf;
- ssize_t st;
+ int st;
buf = kzalloc(cnt, GFP_KERNEL);
if (!buf)
return -ENOMEM;
st = rsxx_creg_read(card, CREG_ADD_CRAM + (u32)*ppos, cnt, buf, 1);
- if (!st)
- st = copy_to_user(ubuf, buf, cnt);
+ if (!st) {
+ if (copy_to_user(ubuf, buf, cnt))
+ st = -EFAULT;
+ }
kfree(buf);
if (st)
return st;
