From 2973dfdb877c17b36c27ba66d71028ff1eb2f32e Mon Sep 17 00:00:00 2001 From: Glauber de Oliveira Costa Date: Sun, 30 Oct 2005 15:03:05 -0800 Subject: [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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ext3/inode.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'fs/ext3/inode.c') diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c index b5da5244e14..5d9b00e2883 100644 --- a/fs/ext3/inode.c +++ b/fs/ext3/inode.c @@ -523,7 +523,6 @@ static int ext3_alloc_branch(handle_t *handle, struct inode *inode, if (!nr) break; branch[n].key = cpu_to_le32(nr); - keys = n+1; /* * Get buffer_head for parent block, zero it out @@ -531,6 +530,9 @@ static int ext3_alloc_branch(handle_t *handle, struct inode *inode, * parent to disk. */ bh = sb_getblk(inode->i_sb, parent); + if (!bh) + break; + keys = n+1; branch[n].bh = bh; lock_buffer(bh); BUFFER_TRACE(bh, "call get_create_access"); @@ -864,6 +866,10 @@ struct buffer_head *ext3_getblk(handle_t *handle, struct inode * inode, if (!*errp && buffer_mapped(&dummy)) { struct buffer_head *bh; bh = sb_getblk(inode->i_sb, dummy.b_blocknr); + if (!bh) { + *errp = -EIO; + goto err; + } if (buffer_new(&dummy)) { J_ASSERT(create != 0); J_ASSERT(handle != 0); @@ -896,6 +902,7 @@ struct buffer_head *ext3_getblk(handle_t *handle, struct inode * inode, } return bh; } +err: return NULL; } -- cgit v1.2.3-18-g5258