From b42db0860e13067fcc7cbfba3966c9e652668bbc Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Mon, 16 Apr 2018 23:06:53 -0700 Subject: xfs: enhance dinode verifier Add several more validations to xfs_dinode_verify: - For LOCAL data fork formats, di_nextents must be 0. - For LOCAL attr fork formats, di_anextents must be 0. - For inodes with no attr fork offset, - format must be XFS_DINODE_FMT_EXTENTS if set at all - di_anextents must be 0. Thanks to dchinner for pointing out a couple related checks I had forgotten to add. Signed-off-by: Eric Sandeen Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199377 Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_inode_buf.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'fs') diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c index ef68b1de006a..1201107eabc6 100644 --- a/fs/xfs/libxfs/xfs_inode_buf.c +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -466,6 +466,8 @@ xfs_dinode_verify( return __this_address; if (di_size > XFS_DFORK_DSIZE(dip, mp)) return __this_address; + if (dip->di_nextents) + return __this_address; /* fall through */ case XFS_DINODE_FMT_EXTENTS: case XFS_DINODE_FMT_BTREE: @@ -484,12 +486,31 @@ xfs_dinode_verify( if (XFS_DFORK_Q(dip)) { switch (dip->di_aformat) { case XFS_DINODE_FMT_LOCAL: + if (dip->di_anextents) + return __this_address; + /* fall through */ case XFS_DINODE_FMT_EXTENTS: case XFS_DINODE_FMT_BTREE: break; default: return __this_address; } + } else { + /* + * If there is no fork offset, this may be a freshly-made inode + * in a new disk cluster, in which case di_aformat is zeroed. + * Otherwise, such an inode must be in EXTENTS format; this goes + * for freed inodes as well. + */ + switch (dip->di_aformat) { + case 0: + case XFS_DINODE_FMT_EXTENTS: + break; + default: + return __this_address; + } + if (dip->di_anextents) + return __this_address; } /* only version 3 or greater inodes are extensively verified here */ -- cgit v1.2.3 From 2c4306f719b083d17df2963bc761777576b8ad1b Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Mon, 16 Apr 2018 23:07:27 -0700 Subject: xfs: set format back to extents if xfs_bmap_extents_to_btree If xfs_bmap_extents_to_btree fails in a mode where we call xfs_iroot_realloc(-1) to de-allocate the root, set the format back to extents. Otherwise we can assume we can dereference ifp->if_broot based on the XFS_DINODE_FMT_BTREE format, and crash. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199423 Signed-off-by: Eric Sandeen Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_bmap.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs') diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 6a7c2f03ea11..040eeda8426f 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -725,12 +725,16 @@ xfs_bmap_extents_to_btree( *logflagsp = 0; if ((error = xfs_alloc_vextent(&args))) { xfs_iroot_realloc(ip, -1, whichfork); + ASSERT(ifp->if_broot == NULL); + XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS); xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return error; } if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) { xfs_iroot_realloc(ip, -1, whichfork); + ASSERT(ifp->if_broot == NULL); + XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS); xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return -ENOSPC; } -- cgit v1.2.3 From 7d83fb14258b9961920cd86f0b921caaeb3ebe85 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 16 Apr 2018 23:07:45 -0700 Subject: xfs: prevent creating negative-sized file via INSERT_RANGE During the "insert range" fallocate operation, i_size grows by the specified 'len' bytes. XFS verifies that i_size + len < s_maxbytes, as it should. But this comparison is done using the signed 'loff_t', and 'i_size + len' can wrap around to a negative value, causing the check to incorrectly pass, resulting in an inode with "negative" i_size. This is possible on 64-bit platforms, where XFS sets s_maxbytes = LLONG_MAX. ext4 and f2fs don't run into this because they set a smaller s_maxbytes. Fix it by using subtraction instead. Reproducer: xfs_io -f file -c "truncate $(((1<<63)-1))" -c "finsert 0 4096" Fixes: a904b1ca5751 ("xfs: Add support FALLOC_FL_INSERT_RANGE for fallocate") Cc: # v4.1+ Originally-From: Eric Biggers Signed-off-by: Eric Biggers Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong [darrick: fix signed integer addition overflow too] Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_file.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 299aee4b7b0b..eed073cc4778 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -778,22 +778,26 @@ xfs_file_fallocate( if (error) goto out_unlock; } else if (mode & FALLOC_FL_INSERT_RANGE) { - unsigned int blksize_mask = i_blocksize(inode) - 1; + unsigned int blksize_mask = i_blocksize(inode) - 1; + loff_t isize = i_size_read(inode); - new_size = i_size_read(inode) + len; if (offset & blksize_mask || len & blksize_mask) { error = -EINVAL; goto out_unlock; } - /* check the new inode size does not wrap through zero */ - if (new_size > inode->i_sb->s_maxbytes) { + /* + * New inode size must not exceed ->s_maxbytes, accounting for + * possible signed overflow. + */ + if (inode->i_sb->s_maxbytes - isize < len) { error = -EFBIG; goto out_unlock; } + new_size = isize + len; /* Offset should be less than i_size */ - if (offset >= i_size_read(inode)) { + if (offset >= isize) { error = -EINVAL; goto out_unlock; } -- cgit v1.2.3 From 7b38460dc8e4eafba06c78f8e37099d3b34d473c Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 17 Apr 2018 19:10:15 -0700 Subject: xfs: don't fail when converting shortform attr to long form during ATTR_REPLACE Kanda Motohiro reported that expanding a tiny xattr into a large xattr fails on XFS because we remove the tiny xattr from a shortform fork and then try to re-add it after converting the fork to extents format having not removed the ATTR_REPLACE flag. This fails because the attr is no longer present, causing a fs shutdown. This is derived from the patch in his bug report, but we really shouldn't ignore a nonzero retval from the remove call. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199119 Reported-by: kanda.motohiro@gmail.com Reviewed-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_attr.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c index ce4a34a2751d..35a124400d60 100644 --- a/fs/xfs/libxfs/xfs_attr.c +++ b/fs/xfs/libxfs/xfs_attr.c @@ -511,7 +511,14 @@ xfs_attr_shortform_addname(xfs_da_args_t *args) if (args->flags & ATTR_CREATE) return retval; retval = xfs_attr_shortform_remove(args); - ASSERT(retval == 0); + if (retval) + return retval; + /* + * Since we have removed the old attr, clear ATTR_REPLACE so + * that the leaf format add routine won't trip over the attr + * not being around. + */ + args->flags &= ~ATTR_REPLACE; } if (args->namelen >= XFS_ATTR_SF_ENTSIZE_MAX || -- cgit v1.2.3