Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into sh/urgent

1 files changed, 21 insertions, 2 deletions

diff --git a/fs/bio.c b/fs/bio.c
index 8abb2dfb2e7c..4bd454fa844e 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -370,6 +370,9 @@ struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs)
 {
 	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_map_data *bmd)
 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;
 
@@ -827,6 +834,12 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 		end = (uaddr + iov[i].iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 		start = uaddr >> PAGE_SHIFT;
 
+		/*
+		 * Overflow, abort
+		 */
+		if (end < start)
+			return ERR_PTR(-EINVAL);
+
 		nr_pages += end - start;
 		len += iov[i].iov_len;
 	}
@@ -955,6 +968,12 @@ static struct bio *__bio_map_user_iov(struct request_queue *q,
 		unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 		unsigned long start = uaddr >> PAGE_SHIFT;
 
+		/*
+		 * Overflow, abort
+		 */
+		if (end < start)
+			return ERR_PTR(-EINVAL);
+
 		nr_pages += end - start;
 		/*
 		 * buffer must be aligned to at least hardsector size for now
@@ -982,7 +1001,7 @@ static struct bio *__bio_map_user_iov(struct request_queue *q,
 		unsigned long start = uaddr >> PAGE_SHIFT;
 		const int local_nr_pages = end - start;
 		const int page_limit = cur_page + local_nr_pages;
-		
+
 		ret = get_user_pages_fast(uaddr, local_nr_pages,
 				write_to_vm, &pages[cur_page]);
 		if (ret < local_nr_pages) {