From: Carlos Maiolino cem@kernel.org
Commit 9f0902091c332b2665951cfb970f60ae7cbdc0f3 upstream
Mounting a filesystem that requires quota state changing will generate a transaction.
We already check for a read-only device; we should do that for norecovery too.
A quotacheck on a norecovery mount, and with the right log size, will cause the mount process to hang on:
[<0>] xlog_grant_head_wait+0x5d/0x2a0 [xfs] [<0>] xlog_grant_head_check+0x112/0x180 [xfs] [<0>] xfs_log_reserve+0xe3/0x260 [xfs] [<0>] xfs_trans_reserve+0x179/0x250 [xfs] [<0>] xfs_trans_alloc+0x101/0x260 [xfs] [<0>] xfs_sync_sb+0x3f/0x80 [xfs] [<0>] xfs_qm_mount_quotas+0xe3/0x2f0 [xfs] [<0>] xfs_mountfs+0x7ad/0xc20 [xfs] [<0>] xfs_fs_fill_super+0x762/0xa50 [xfs] [<0>] get_tree_bdev_flags+0x131/0x1d0 [<0>] vfs_get_tree+0x26/0xd0 [<0>] vfs_cmd_create+0x59/0xe0 [<0>] __do_sys_fsconfig+0x4e3/0x6b0 [<0>] do_syscall_64+0x82/0x160 [<0>] entry_SYSCALL_64_after_hwframe+0x76/0x7e
This is caused by a transaction running with bogus initialized head/tail
I initially hit this while running generic/050, with random log sizes, but I managed to reproduce it reliably here with the steps below:
mkfs.xfs -f -lsize=1025M -f -b size=4096 -m crc=1,reflink=1,rmapbt=1, -i sparse=1 /dev/vdb2 > /dev/null mount -o usrquota,grpquota,prjquota /dev/vdb2 /mnt xfs_io -x -c 'shutdown -f' /mnt umount /mnt mount -o ro,norecovery,usrquota,grpquota,prjquota /dev/vdb2 /mnt
Last mount hangs up
As we add yet another validation if quota state is changing, this also add a new helper named xfs_qm_validate_state_change(), factoring the quota state changes out of xfs_qm_newmount() to reduce cluttering within it.
Signed-off-by: Carlos Maiolino cmaiolino@redhat.com Reviewed-by: Darrick J. Wong djwong@kernel.org Signed-off-by: Carlos Maiolino cem@kernel.org --- fs/xfs/xfs_qm_bhv.c | 49 ++++++++++++++++++++++++++++++++++--------------- 1 file changed, 34 insertions(+), 15 deletions(-)
diff --git a/fs/xfs/xfs_qm_bhv.c b/fs/xfs/xfs_qm_bhv.c index ed1d597c30ca25..dabb1d6d7e463e 100644 --- a/fs/xfs/xfs_qm_bhv.c +++ b/fs/xfs/xfs_qm_bhv.c @@ -79,6 +79,28 @@ xfs_qm_statvfs( } }
+STATIC int +xfs_qm_validate_state_change( + struct xfs_mount *mp, + uint uqd, + uint gqd, + uint pqd) +{ + int state; + + /* Is quota state changing? */ + state = ((uqd && !XFS_IS_UQUOTA_ON(mp)) || + (!uqd && XFS_IS_UQUOTA_ON(mp)) || + (gqd && !XFS_IS_GQUOTA_ON(mp)) || + (!gqd && XFS_IS_GQUOTA_ON(mp)) || + (pqd && !XFS_IS_PQUOTA_ON(mp)) || + (!pqd && XFS_IS_PQUOTA_ON(mp))); + + return state && + (xfs_dev_is_read_only(mp, "changing quota state") || + xfs_has_norecovery(mp)); +} + int xfs_qm_newmount( xfs_mount_t *mp, @@ -98,24 +120,21 @@ xfs_qm_newmount( }
/* - * If the device itself is read-only, we can't allow - * the user to change the state of quota on the mount - - * this would generate a transaction on the ro device, - * which would lead to an I/O error and shutdown + * If the device itself is read-only and/or in norecovery + * mode, we can't allow the user to change the state of + * quota on the mount - this would generate a transaction + * on the ro device, which would lead to an I/O error and + * shutdown. */
- if (((uquotaondisk && !XFS_IS_UQUOTA_ON(mp)) || - (!uquotaondisk && XFS_IS_UQUOTA_ON(mp)) || - (gquotaondisk && !XFS_IS_GQUOTA_ON(mp)) || - (!gquotaondisk && XFS_IS_GQUOTA_ON(mp)) || - (pquotaondisk && !XFS_IS_PQUOTA_ON(mp)) || - (!pquotaondisk && XFS_IS_PQUOTA_ON(mp))) && - xfs_dev_is_read_only(mp, "changing quota state")) { + if (xfs_qm_validate_state_change(mp, uquotaondisk, + gquotaondisk, pquotaondisk)) { + xfs_warn(mp, "please mount with%s%s%s%s.", - (!quotaondisk ? "out quota" : ""), - (uquotaondisk ? " usrquota" : ""), - (gquotaondisk ? " grpquota" : ""), - (pquotaondisk ? " prjquota" : "")); + (!quotaondisk ? "out quota" : ""), + (uquotaondisk ? " usrquota" : ""), + (gquotaondisk ? " grpquota" : ""), + (pquotaondisk ? " prjquota" : "")); return -EPERM; }