[PATCH] Test for sb_getblk return value
This patch adds tests for the return value of sb_getblk() in the ext2/3
filesystems. In fs/buffer.c it is stated that the getblk() function never
fails. However, it does can return NULL in some situations due to I/O
errors, which may lead us to NULL pointer dereferences
Signed-off-by: Glauber de Oliveira Costa <glommer@br.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index fdba4d1..e7d3f05 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -440,6 +440,10 @@
* the pointer to new one, then send parent to disk.
*/
bh = sb_getblk(inode->i_sb, parent);
+ if (!bh) {
+ err = -EIO;
+ break;
+ }
lock_buffer(bh);
memset(bh->b_data, 0, blocksize);
branch[n].bh = bh;
