From 647882ad974347f8574baba5d8d3c39b47c1a2c0 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Thu, 2 Feb 2017 15:13:58 -0800 Subject: [PATCH] xfs: filter out obviously bad btree pointers BugLink: http://bugs.launchpad.net/bugs/1681875 commit d5a91baeb6033c3392121e4d5c011cdc08dfa9f7 upstream. Don't let anybody load an obviously bad btree pointer. Since the values come from disk, we must return an error, not just ASSERT. Signed-off-by: Darrick J. Wong Reviewed-by: Eric Sandeen Signed-off-by: Greg Kroah-Hartman Signed-off-by: Tim Gardner --- fs/xfs/libxfs/xfs_bmap.c | 5 +---- fs/xfs/libxfs/xfs_btree.c | 3 ++- fs/xfs/libxfs/xfs_btree.h | 2 +- 3 files changed, 4 insertions(+), 6 deletions(-) diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index bfc00de5c6f1..d79c66d1215d 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -1278,7 +1278,6 @@ xfs_bmap_read_extents( /* REFERENCED */ xfs_extnum_t room; /* number of entries there's room for */ - bno = NULLFSBLOCK; mp = ip->i_mount; ifp = XFS_IFORK_PTR(ip, whichfork); exntf = (whichfork != XFS_DATA_FORK) ? XFS_EXTFMT_NOSTATE : @@ -1291,9 +1290,7 @@ xfs_bmap_read_extents( ASSERT(level > 0); pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes); bno = be64_to_cpu(*pp); - ASSERT(bno != NULLFSBLOCK); - ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount); - ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks); + /* * Go down the tree until leaf level is reached, following the first * pointer (leftmost) at each level. diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index 21e6a6ab6b9a..2849d3fa3d0b 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -810,7 +810,8 @@ xfs_btree_read_bufl( xfs_daddr_t d; /* real disk block address */ int error; - ASSERT(fsbno != NULLFSBLOCK); + if (!XFS_FSB_SANITY_CHECK(mp, fsbno)) + return -EFSCORRUPTED; d = XFS_FSB_TO_DADDR(mp, fsbno); error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d, mp->m_bsize, lock, &bp, ops); diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h index b69b947c4c1b..33a8f8694d30 100644 --- a/fs/xfs/libxfs/xfs_btree.h +++ b/fs/xfs/libxfs/xfs_btree.h @@ -456,7 +456,7 @@ static inline int xfs_btree_get_level(struct xfs_btree_block *block) #define XFS_FILBLKS_MAX(a,b) max_t(xfs_filblks_t, (a), (b)) #define XFS_FSB_SANITY_CHECK(mp,fsb) \ - (XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \ + (fsb && XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \ XFS_FSB_TO_AGBNO(mp, fsb) < mp->m_sb.sb_agblocks) /* -- 2.39.5