2003-02-05 20:20:16

by Alexandre Pereira Nunes

[permalink] [raw]
Subject: promiscuous bttv parameter checking (2.4.21-pre3)

Hi,

As of linux 2.4.21-pre3, bttv driver fails to check the "channel"
attribute correctly. This is caused because there is no check for
negative values on the channel parameter (at least ) in ioctls
VIDIOCGCHAN (bttv-driver.c:1510) and VIDIOCSCHAN (same file, at line
1537). Negative parameters, though invalid, are passed along.

While in the first case (VIDIOCGCHAN) I see no dark effects other than
the wacky channel name in the name member of the returned structure, it
is possible that passing the negative value in VIDIOCSCHAN spots
side-effects, specially in the function bt848_muxsel.


(A cc: went to the maintainer. Any questions please cc: me since I'm not
subscribed to the kernel mailing list).


Best regards,


Alexandre