2023-02-27 19:44:17

by George Kennedy

Subject: [PATCH] vc_screen: modify vcs_size() handling in vcs_read()

Restore the vcs_size() handling in vcs_read() to what
it had been in previous version.

Suggested-by: Jiri Slaby <[email protected]>
Signed-off-by: George Kennedy <[email protected]>
---
drivers/tty/vt/vc_screen.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c
index f566eb1839dc..c0a2273bb998 100644
--- a/drivers/tty/vt/vc_screen.c
+++ b/drivers/tty/vt/vc_screen.c
@@ -414,10 +414,8 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
*/
size = vcs_size(vc, attr, uni_mode);
if (size < 0) {
- if (read)
- break;
ret = size;
- goto unlock_out;
+ break;
}
if (pos >= size)
break;
--
2.31.1

2023-02-27 20:07:30

by Linus Torvalds

Subject: Re: [PATCH] vc_screen: modify vcs_size() handling in vcs_read()

On Mon, Feb 27, 2023 at 11:43 AM George Kennedy
<[email protected]> wrote:
>
> Restore the vcs_size() handling in vcs_read() to what
> it had been in previous version.
>
> Suggested-by: Jiri Slaby <[email protected]>
> Signed-off-by: George Kennedy <[email protected]>

Please also add a

Fixes: 226fae124b2d ("vc_screen: move load of struct vc_data
pointer in vcs_read() to avoid UAF")

or whatever it was that broke this, so that we have that context to
what the "previous version" actually was.

Linus