On 07. 06. 22, 16:19, Ilpo Järvinen wrote:
On Tue, 7 Jun 2022, Jiri Slaby wrote:
Only the return value of copy_to_user() is checked in con_get_unimap().
Do the same for put_user() of the count too.
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/tty/vt/consolemap.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/vt/consolemap.c b/drivers/tty/vt/consolemap.c
index 831450f2bfd1..92b5dddb00d9 100644
--- a/drivers/tty/vt/consolemap.c
+++ b/drivers/tty/vt/consolemap.c
@@ -813,7 +813,8 @@ int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct,
console_unlock();
if (copy_to_user(list, unilist, min(ect, ct) * sizeof(*unilist)))
ret = -EFAULT;
- put_user(ect, uct);
+ if (put_user(ect, uct))
+ ret = -EFAULT;
kvfree(unilist);
return ret ? ret : (ect <= ct) ? 0 : -ENOMEM;
}
Doesn't this fix something?
If you mean a Fixes tag, this is pre-git.
If you mean a bug, well, likely yes, users now get informed. But I don't
think anyone cares ;). But who knows, maybe we will start seeing
userspace failures now (as they might not provide writable count field
-- unlikely). That's one of the reasons why I did this as a separate
commit. Let's see if are going to revert this or not...
thanks,
--
js
suse labs
