[003/289] block: limit vec count in bio_kmalloc() and bio_alloc_map_data()

Greg KH
2010-12-08T02:04:39Z

From: Jens Axboe <jaxboe@fusionio.com>

commit f3f63c1c28bc861a931fac283b5bc3585efb8967 upstream.

Reported-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
fs/bio.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/fs/bio.c
+++ b/fs/bio.c
@@ -370,6 +370,9 @@ struct bio *bio_kmalloc(gfp_t gfp_mask,
{
struct bio *bio;

+ if (nr_iovecs > UIO_MAXIOV)
+ return NULL;
+
bio = kmalloc(sizeof(struct bio) + nr_iovecs * sizeof(struct bio_vec),
gfp_mask);
if (unlikely(!bio))
@@ -697,8 +700,12 @@ static void bio_free_map_data(struct bio
static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
gfp_t gfp_mask)
{
- struct bio_map_data *bmd = kmalloc(sizeof(*bmd), gfp_mask);
+ struct bio_map_data *bmd;
+
+ if (iov_count > UIO_MAXIOV)
+ return NULL;

+ bmd = kmalloc(sizeof(*bmd), gfp_mask);
if (!bmd)
return NULL;