From: Utako Kusaka Date: Thu, 28 Jul 2011 02:11:20 +0000 (-0400) Subject: ext4: Fix overflow caused by missing cast in ext4_fallocate() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=29ae07b702cb77dbc24b0843f15ee8cf8a642311;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git ext4: Fix overflow caused by missing cast in ext4_fallocate() The logical block number in map.l_blk is a __u32, and so before we shift it left, by the block size, we neeed cast it to a 64-bit size. Otherwise i_size can be corrupted on an ENOSPC. # df -T /mnt/mp1 Filesystem Type 1K-blocks Used Available Use% Mounted on /dev/sda6 ext4 9843276 153056 9190200 2% /mnt/mp1 # fallocate -o 0 -l 2199023251456 /mnt/mp1/testfile fallocate: /mnt/mp1/testfile: fallocate failed: No space left on device # stat /mnt/mp1/testfile File: `/mnt/mp1/testfile' Size: 4293656576 Blocks: 19380440 IO Block: 4096 regular file Device: 806h/2054d Inode: 12 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2011-07-25 13:01:31.414490496 +0900 Modify: 2011-07-25 13:01:31.414490496 +0900 Change: 2011-07-25 13:01:31.454490495 +0900 Signed-off-by: Utako Kusaka Signed-off-by: "Theodore Ts'o" -- fs/ext4/extents.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) --- diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index a25bbdc7d493..57cf568a98ab 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3824,7 +3824,7 @@ retry: blkbits) >> blkbits)) new_size = offset + len; else - new_size = (map.m_lblk + ret) << blkbits; + new_size = ((loff_t) map.m_lblk + ret) << blkbits; ext4_falloc_update_inode(inode, mode, new_size, (map.m_flags & EXT4_MAP_NEW));