]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
ext4: fix loff_t overflow in ext4_max_bitmap_size()
authorRitesh Harjani <riteshh@linux.ibm.com>
Sat, 5 Jun 2021 05:09:32 +0000 (10:39 +0530)
committerTheodore Ts'o <tytso@mit.edu>
Fri, 1 Oct 2021 04:03:51 +0000 (00:03 -0400)
commit75ca6ad408f459f00b09a64f04c774559848c097
treefede0d63735d43b1a774ff76fc80597fe0a29e13
parent6fed83957f21eff11c8496e9f24253b03d2bc1dc
ext4: fix loff_t overflow in ext4_max_bitmap_size()

We should use unsigned long long rather than loff_t to avoid
overflow in ext4_max_bitmap_size() for comparison before returning.
w/o this patch sbi->s_bitmap_maxbytes was becoming a negative
value due to overflow of upper_limit (with has_huge_files as true)

Below is a quick test to trigger it on a 64KB pagesize system.

sudo mkfs.ext4 -b 65536 -O ^has_extents,^64bit /dev/loop2
sudo mount /dev/loop2 /mnt
sudo echo "hello" > /mnt/hello  -> This will error out with
"echo: write error: File too large"

Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/594f409e2c543e90fd836b78188dfa5c575065ba.1622867594.git.riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fs/ext4/super.c