From: Theodore Ts'o <[email protected]> commit f70f362b4a6fe47c239dbfb3efc0cc2c10e4f09c upstream.
If the EOFBLOCK_FL flag is set when it should not be and the inode is zero length, then eh_entries is zero, and ex is NULL, so dereferencing ex to print ex->ee_block causes a kernel OOPS in ext4_ext_map_blocks(). On top of that, the error message which is printed isn't very helpful. So we fix this by printing something more explanatory which doesn't involve trying to print ex->ee_block. Addresses-Google-Bug: #2655740 Signed-off-by: "Theodore Ts'o" <[email protected]> Signed-off-by: Paul Gortmaker <[email protected]> --- fs/ext4/extents.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index a1d3f7c..8e8a7a4 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3381,8 +3381,9 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, */ if (unlikely(path[depth].p_ext == NULL && depth != 0)) { EXT4_ERROR_INODE(inode, "bad extent address " - "iblock: %d, depth: %d pblock %lld", - iblock, depth, path[depth].p_block); + "iblock: %lu, depth: %d pblock %lld", + (unsigned long) iblock, depth, + path[depth].p_block); err = -EIO; goto out2; } @@ -3512,8 +3513,8 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, if (unlikely(ext4_test_inode_flag(inode, EXT4_INODE_EOFBLOCKS))) { if (unlikely(!eh->eh_entries)) { EXT4_ERROR_INODE(inode, - "eh->eh_entries == 0 ee_block %d", - ex->ee_block); + "eh->eh_entries == 0 and " + "EOFBLOCKS_FL set"); err = -EIO; goto out2; } -- 1.7.3.3 _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
