diff options
| author | Ritesh Harjani <riteshh@linux.ibm.com> | 2020-05-05 17:43:14 +0200 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2020-06-03 23:16:54 -0400 |
| commit | 175efa81feb8405676e0136d97b10380179c92e0 (patch) | |
| tree | dedc073038563e46c894404a9802869434f2c12a | |
| parent | 9f364e1d9537d44fdf58deeeddb51277d8327ce5 (diff) | |
ext4: fix EXT4_MAX_LOGICAL_BLOCK macro
ext4 supports max number of logical blocks in a file to be 0xffffffff.
(This is since ext4_extent's ee_block is __le32).
This means that EXT4_MAX_LOGICAL_BLOCK should be 0xfffffffe (starting
from 0 logical offset). This patch fixes this.
The issue was seen when ext4 moved to iomap_fiemap API and when
overlayfs was mounted on top of ext4. Since overlayfs was missing
filemap_check_ranges(), so it could pass a arbitrary huge length which
lead to overflow of map.m_len logic.
This patch fixes that.
Fixes: d3b6f23f7167 ("ext4: move ext4_fiemap to use iomap framework")
Reported-by: syzbot+77fa5bdb65cc39711820@syzkaller.appspotmail.com
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200505154324.3226743-2-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| -rw-r--r-- | fs/ext4/ext4.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index a94e7aaea6e6..1eb07ca91fca 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -733,7 +733,7 @@ enum { #define EXT4_MAX_BLOCK_FILE_PHYS 0xFFFFFFFF /* Max logical block we can support */ -#define EXT4_MAX_LOGICAL_BLOCK 0xFFFFFFFF +#define EXT4_MAX_LOGICAL_BLOCK 0xFFFFFFFE /* * Structure of an inode on the disk |