| Message ID | 1584364028-122886-3-git-send-email-zhengbin13@huawei.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | xfs: always init fdblocks in mount and avoid f_bfree overflow | expand |
> + if (sbp->sb_fdblocks < mp->m_alloc_set_aside) { > + xfs_alert(mp, "Corruption detected. Please run xfs_repair."); > + error = -EFSCORRUPTED; > + goto out_log_dealloc; > + } > + > /* > * Get and sanity-check the root inode. > * Save the pointer to it in the mount structure. > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index 2094386..9dcf772 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -755,7 +755,8 @@ xfs_fs_statfs( > statp->f_blocks = sbp->sb_dblocks - lsize; > spin_unlock(&mp->m_sb_lock); > > - statp->f_bfree = fdblocks - mp->m_alloc_set_aside; > + /* make sure statp->f_bfree does not underflow */ > + statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0); How can this happen with the above hunk applies? And even if we'd need to do the sanity chck it shold be two separate patches.
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index dc41801..a223af4 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -816,6 +816,12 @@ xfs_mountfs( if (error) goto out_log_dealloc; + if (sbp->sb_fdblocks < mp->m_alloc_set_aside) { + xfs_alert(mp, "Corruption detected. Please run xfs_repair."); + error = -EFSCORRUPTED; + goto out_log_dealloc; + } + /* * Get and sanity-check the root inode. * Save the pointer to it in the mount structure. diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 2094386..9dcf772 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -755,7 +755,8 @@ xfs_fs_statfs( statp->f_blocks = sbp->sb_dblocks - lsize; spin_unlock(&mp->m_sb_lock); - statp->f_bfree = fdblocks - mp->m_alloc_set_aside; + /* make sure statp->f_bfree does not underflow */ + statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0); statp->f_bavail = statp->f_bfree; fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
If fdblocks < mp->m_alloc_set_aside, statp->f_bfree will overflow. When we df -h /mnt(xfs mount point), will show this: Filesystem Size Used Avail Use% Mounted on /dev/loop0 13M -64Z -32K 100% /mnt Make sure statp->f_bfree does not underflow. PS: add fdblocks check in mount. Signed-off-by: Zheng Bin <zhengbin13@huawei.com> --- fs/xfs/xfs_mount.c | 6 ++++++ fs/xfs/xfs_super.c | 3 ++- 2 files changed, 8 insertions(+), 1 deletion(-) -- 2.7.4