summaryrefslogtreecommitdiff
path: root/fs/ext4
diff options
context:
space:
mode:
authorJan Kara <jack@suse.cz>2021-04-12 13:23:33 +0300
committerTheodore Ts'o <tytso@mit.edu>2021-06-17 17:53:19 +0300
commitd0b040f5f2557b2f507c01e88ad8cff424fdc6a9 (patch)
tree09cfb51d1f41cf9c30209d2bc4d0ab286fc1b9d2 /fs/ext4
parent614124bea77e452aa6df7a8714e8bc820b489922 (diff)
downloadlinux-d0b040f5f2557b2f507c01e88ad8cff424fdc6a9.tar.xz
ext4: fix overflow in ext4_iomap_alloc()
A code in iomap alloc may overflow block number when converting it to byte offset. Luckily this is mostly harmless as we will just use more expensive method of writing using unwritten extents even though we are writing beyond i_size. Cc: stable@kernel.org Fixes: 378f32bab371 ("ext4: introduce direct I/O write using iomap infrastructure") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210412102333.2676-4-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4')
-rw-r--r--fs/ext4/inode.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index fe6045a46599..211acfba3af7 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3418,7 +3418,7 @@ retry:
* i_disksize out to i_size. This could be beyond where direct I/O is
* happening and thus expose allocated blocks to direct I/O reads.
*/
- else if ((map->m_lblk * (1 << blkbits)) >= i_size_read(inode))
+ else if (((loff_t)map->m_lblk << blkbits) >= i_size_read(inode))
m_flags = EXT4_GET_BLOCKS_CREATE;
else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT;