From 69775fd15dc78e0547af45fb3e375d5423cb21b1 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Thu, 26 Jul 2018 10:10:42 -0700 Subject: [PATCH] xfs: verify icount in superblock write Add a helper predicate to check the inode count for sanity, then use it in the superblock write verifier to inspect sb_icount. Signed-off-by: Darrick J. Wong Reviewed-by: Bill O'Donnell Reviewed-by: Eric Sandeen --- fs/xfs/libxfs/xfs_sb.c | 3 ++- fs/xfs/libxfs/xfs_types.c | 34 ++++++++++++++++++++++++++++++++++ fs/xfs/libxfs/xfs_types.h | 1 + 3 files changed, 37 insertions(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index 3d29f4a5242f..05e7ed1b8022 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -154,9 +154,10 @@ xfs_validate_sb_write( * Carry out additional sb summary counter sanity checks when we write * the superblock. We skip this in the read validator because there * could be newer superblocks in the log and if the values are garbage - * we'll recalculate them at the end of log mount. + * even after replay we'll recalculate them at the end of log mount. */ if (sbp->sb_fdblocks > sbp->sb_dblocks || + !xfs_verify_icount(mp, sbp->sb_icount) || sbp->sb_ifree > sbp->sb_icount) { xfs_warn(mp, "SB summary counter sanity check failed"); return -EFSCORRUPTED; diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c index 2e2a243cef2e..33a5ca346baf 100644 --- a/fs/xfs/libxfs/xfs_types.c +++ b/fs/xfs/libxfs/xfs_types.c @@ -171,3 +171,37 @@ xfs_verify_rtbno( { return rtbno < mp->m_sb.sb_rblocks; } + +/* Calculate the range of valid icount values. */ +static void +xfs_icount_range( + struct xfs_mount *mp, + unsigned long long *min, + unsigned long long *max) +{ + unsigned long long nr_inos = 0; + xfs_agnumber_t agno; + + /* root, rtbitmap, rtsum all live in the first chunk */ + *min = XFS_INODES_PER_CHUNK; + + for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) { + xfs_agino_t first, last; + + xfs_agino_range(mp, agno, &first, &last); + nr_inos += last - first + 1; + } + *max = nr_inos; +} + +/* Sanity-checking of inode counts. */ +bool +xfs_verify_icount( + struct xfs_mount *mp, + unsigned long long icount) +{ + unsigned long long min, max; + + xfs_icount_range(mp, &min, &max); + return icount >= min && icount <= max; +} diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h index 4055d62f690c..b9e6c89284c3 100644 --- a/fs/xfs/libxfs/xfs_types.h +++ b/fs/xfs/libxfs/xfs_types.h @@ -165,5 +165,6 @@ bool xfs_verify_ino(struct xfs_mount *mp, xfs_ino_t ino); bool xfs_internal_inum(struct xfs_mount *mp, xfs_ino_t ino); bool xfs_verify_dir_ino(struct xfs_mount *mp, xfs_ino_t ino); bool xfs_verify_rtbno(struct xfs_mount *mp, xfs_rtblock_t rtbno); +bool xfs_verify_icount(struct xfs_mount *mp, unsigned long long icount); #endif /* __XFS_TYPES_H__ */