ext4: fix NULL pointer dereference in ext4_mark_inode_dirty()
[ Upstream commitwifi-calibration5e1021f2b6
] ext4_reserve_inode_write() in ext4_mark_inode_dirty() could fail on error (e.g. EIO) and iloc.bh can be NULL in this case. But the error is ignored in the following "if" condition and ext4_expand_extra_isize() might be called with NULL iloc.bh set, which triggers NULL pointer dereference. This is uncovered by commit8b4953e13f
("ext4: reserve code points for the project quota feature"), which enlarges the ext4_inode size, and run the following script on new kernel but with old mke2fs: #/bin/bash mnt=/mnt/ext4 devname=ext4-error dev=/dev/mapper/$devname fsimg=/home/fs.img trap cleanup 0 1 2 3 9 15 cleanup() { umount $mnt >/dev/null 2>&1 dmsetup remove $devname losetup -d $backend_dev rm -f $fsimg exit 0 } rm -f $fsimg fallocate -l 1g $fsimg backend_dev=`losetup -f --show $fsimg` devsize=`blockdev --getsz $backend_dev` good_tab="0 $devsize linear $backend_dev 0" error_tab="0 $devsize error $backend_dev 0" dmsetup create $devname --table "$good_tab" mkfs -t ext4 $dev mount -t ext4 -o errors=continue,strictatime $dev $mnt dmsetup load $devname --table "$error_tab" && dmsetup resume $devname echo 3 > /proc/sys/vm/drop_caches ls -l $mnt exit 0 [ Patch changed to simplify the function a tiny bit. -- Ted ] Signed-off-by: Eryu Guan <guaneryu@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
parent
6e939f787e
commit
7925f4fb3d
|
@ -5094,6 +5094,8 @@ int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
|
|||
might_sleep();
|
||||
trace_ext4_mark_inode_dirty(inode, _RET_IP_);
|
||||
err = ext4_reserve_inode_write(handle, inode, &iloc);
|
||||
if (err)
|
||||
return err;
|
||||
if (ext4_handle_valid(handle) &&
|
||||
EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
|
||||
!ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
|
||||
|
@ -5124,9 +5126,7 @@ int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
|
|||
}
|
||||
}
|
||||
}
|
||||
if (!err)
|
||||
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
|
||||
return err;
|
||||
return ext4_mark_iloc_dirty(handle, inode, &iloc);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
Loading…
Reference in New Issue