diff options
| author | Dan Rosenberg | 2010-09-27 12:30:28 -0400 |
|---|---|---|
| committer | Linus Torvalds | 2010-09-27 16:29:06 -0700 |
| commit | 252a52aa4fa22a668f019e55b3aac3ff71ec1c29 (patch) | |
| tree | 93e0def0cef2ba85c203f2c20b86cda4b6190843 | |
| parent | 95929eff2cb01e9858779283795f4e3943ee020d (diff) | |
Fix pktcdvd ioctl dev_minor range check
The PKT_CTRL_CMD_STATUS device ioctl retrieves a pointer to a
pktcdvd_device from the global pkt_devs array. The index into this
array is provided directly by the user and is a signed integer, so the
comparison to ensure that it falls within the bounds of this array will
fail when provided with a negative index.
This can be used to read arbitrary kernel memory or cause a crash due to
an invalid pointer dereference. This can be exploited by users with
permission to open /dev/pktcdvd/control (on many distributions, this is
readable by group "cdrom").
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
[ Rather than add a cast, just make the function take the right type -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/block/pktcdvd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index b1cbeb59bb76..37a2bb595076 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -2369,7 +2369,7 @@ static void pkt_release_dev(struct pktcdvd_device *pd, int flush) pkt_shrink_pktlist(pd); } -static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor) +static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor) { if (dev_minor >= MAX_WRITERS) return NULL; |