Searched hist:"2 ba48b20" (Results 1 – 3 of 3) sorted by relevance
| /openbmc/linux/fs/btrfs/ |
| H A D | disk-io.h | 2ba48b20 Wed Dec 21 17:59:17 CST 2022 Qu Wenruo <wqu@suse.com> btrfs: fix compat_ro checks against remount
[BUG]
Even with commit 81d5d61454c3 ("btrfs: enhance unsupported compat RO
flags handling"), btrfs can still mount a fs with unsupported compat_ro
flags read-only, then remount it RW:
# btrfs ins dump-super /dev/loop0 | grep compat_ro_flags -A 3
compat_ro_flags 0x403
( FREE_SPACE_TREE |
FREE_SPACE_TREE_VALID |
unknown flag: 0x400 )
# mount /dev/loop0 /mnt/btrfs
mount: /mnt/btrfs: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error.
dmesg(1) may have more information after failed mount system call.
^^^ RW mount failed as expected ^^^
# dmesg -t | tail -n5
loop0: detected capacity change from 0 to 1048576
BTRFS: device fsid cb5b82f5-0fdd-4d81-9b4b-78533c324afa devid 1 transid 7 /dev/loop0 scanned by mount (1146)
BTRFS info (device loop0): using crc32c (crc32c-intel) checksum algorithm
BTRFS info (device loop0): using free space tree
BTRFS error (device loop0): cannot mount read-write because of unknown compat_ro features (0x403)
BTRFS error (device loop0): open_ctree failed
# mount /dev/loop0 -o ro /mnt/btrfs
# mount -o remount,rw /mnt/btrfs
^^^ RW remount succeeded unexpectedly ^^^
[CAUSE]
Currently we use btrfs_check_features() to check compat_ro flags against
our current mount flags.
That function get reused between open_ctree() and btrfs_remount().
But for btrfs_remount(), the super block we passed in still has the old
mount flags, thus btrfs_check_features() still believes we're mounting
read-only.
[FIX]
Replace the existing @sb argument with @is_rw_mount.
As originally we only use @sb to determine if the mount is RW.
Now it's callers' responsibility to determine if the mount is RW, and
since there are only two callers, the check is pretty simple:
- caller in open_ctree()
Just pass !sb_rdonly().
- caller in btrfs_remount()
Pass !(*flags & SB_RDONLY), as our check should be against the new
flags.
Now we can correctly reject the RW remount:
# mount /dev/loop0 -o ro /mnt/btrfs
# mount -o remount,rw /mnt/btrfs
mount: /mnt/btrfs: mount point not mounted or bad option.
dmesg(1) may have more information after failed mount system call.
# dmesg -t | tail -n 1
BTRFS error (device loop0: state M): cannot mount read-write because of unknown compat_ro features (0x403)
Reported-by: Chung-Chiang Cheng <shepjeng@gmail.com>
Fixes: 81d5d61454c3 ("btrfs: enhance unsupported compat RO flags handling")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
| H A D | super.c | 2ba48b20 Wed Dec 21 17:59:17 CST 2022 Qu Wenruo <wqu@suse.com> btrfs: fix compat_ro checks against remount
[BUG]
Even with commit 81d5d61454c3 ("btrfs: enhance unsupported compat RO
flags handling"), btrfs can still mount a fs with unsupported compat_ro
flags read-only, then remount it RW:
# btrfs ins dump-super /dev/loop0 | grep compat_ro_flags -A 3
compat_ro_flags 0x403
( FREE_SPACE_TREE |
FREE_SPACE_TREE_VALID |
unknown flag: 0x400 )
# mount /dev/loop0 /mnt/btrfs
mount: /mnt/btrfs: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error.
dmesg(1) may have more information after failed mount system call.
^^^ RW mount failed as expected ^^^
# dmesg -t | tail -n5
loop0: detected capacity change from 0 to 1048576
BTRFS: device fsid cb5b82f5-0fdd-4d81-9b4b-78533c324afa devid 1 transid 7 /dev/loop0 scanned by mount (1146)
BTRFS info (device loop0): using crc32c (crc32c-intel) checksum algorithm
BTRFS info (device loop0): using free space tree
BTRFS error (device loop0): cannot mount read-write because of unknown compat_ro features (0x403)
BTRFS error (device loop0): open_ctree failed
# mount /dev/loop0 -o ro /mnt/btrfs
# mount -o remount,rw /mnt/btrfs
^^^ RW remount succeeded unexpectedly ^^^
[CAUSE]
Currently we use btrfs_check_features() to check compat_ro flags against
our current mount flags.
That function get reused between open_ctree() and btrfs_remount().
But for btrfs_remount(), the super block we passed in still has the old
mount flags, thus btrfs_check_features() still believes we're mounting
read-only.
[FIX]
Replace the existing @sb argument with @is_rw_mount.
As originally we only use @sb to determine if the mount is RW.
Now it's callers' responsibility to determine if the mount is RW, and
since there are only two callers, the check is pretty simple:
- caller in open_ctree()
Just pass !sb_rdonly().
- caller in btrfs_remount()
Pass !(*flags & SB_RDONLY), as our check should be against the new
flags.
Now we can correctly reject the RW remount:
# mount /dev/loop0 -o ro /mnt/btrfs
# mount -o remount,rw /mnt/btrfs
mount: /mnt/btrfs: mount point not mounted or bad option.
dmesg(1) may have more information after failed mount system call.
# dmesg -t | tail -n 1
BTRFS error (device loop0: state M): cannot mount read-write because of unknown compat_ro features (0x403)
Reported-by: Chung-Chiang Cheng <shepjeng@gmail.com>
Fixes: 81d5d61454c3 ("btrfs: enhance unsupported compat RO flags handling")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
| H A D | disk-io.c | 2ba48b20 Wed Dec 21 17:59:17 CST 2022 Qu Wenruo <wqu@suse.com> btrfs: fix compat_ro checks against remount
[BUG]
Even with commit 81d5d61454c3 ("btrfs: enhance unsupported compat RO
flags handling"), btrfs can still mount a fs with unsupported compat_ro
flags read-only, then remount it RW:
# btrfs ins dump-super /dev/loop0 | grep compat_ro_flags -A 3
compat_ro_flags 0x403
( FREE_SPACE_TREE |
FREE_SPACE_TREE_VALID |
unknown flag: 0x400 )
# mount /dev/loop0 /mnt/btrfs
mount: /mnt/btrfs: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error.
dmesg(1) may have more information after failed mount system call.
^^^ RW mount failed as expected ^^^
# dmesg -t | tail -n5
loop0: detected capacity change from 0 to 1048576
BTRFS: device fsid cb5b82f5-0fdd-4d81-9b4b-78533c324afa devid 1 transid 7 /dev/loop0 scanned by mount (1146)
BTRFS info (device loop0): using crc32c (crc32c-intel) checksum algorithm
BTRFS info (device loop0): using free space tree
BTRFS error (device loop0): cannot mount read-write because of unknown compat_ro features (0x403)
BTRFS error (device loop0): open_ctree failed
# mount /dev/loop0 -o ro /mnt/btrfs
# mount -o remount,rw /mnt/btrfs
^^^ RW remount succeeded unexpectedly ^^^
[CAUSE]
Currently we use btrfs_check_features() to check compat_ro flags against
our current mount flags.
That function get reused between open_ctree() and btrfs_remount().
But for btrfs_remount(), the super block we passed in still has the old
mount flags, thus btrfs_check_features() still believes we're mounting
read-only.
[FIX]
Replace the existing @sb argument with @is_rw_mount.
As originally we only use @sb to determine if the mount is RW.
Now it's callers' responsibility to determine if the mount is RW, and
since there are only two callers, the check is pretty simple:
- caller in open_ctree()
Just pass !sb_rdonly().
- caller in btrfs_remount()
Pass !(*flags & SB_RDONLY), as our check should be against the new
flags.
Now we can correctly reject the RW remount:
# mount /dev/loop0 -o ro /mnt/btrfs
# mount -o remount,rw /mnt/btrfs
mount: /mnt/btrfs: mount point not mounted or bad option.
dmesg(1) may have more information after failed mount system call.
# dmesg -t | tail -n 1
BTRFS error (device loop0: state M): cannot mount read-write because of unknown compat_ro features (0x403)
Reported-by: Chung-Chiang Cheng <shepjeng@gmail.com>
Fixes: 81d5d61454c3 ("btrfs: enhance unsupported compat RO flags handling")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|