From: Darrick J. Wong <djwong@xxxxxxxxxx> Pass a transaction context so that a new caller can walk the attr names and query the values all in one go without deadlocking on nested buffer access. While we're at it, make the existing xfs_repair callers try to use empty transactions so that we don't deadlock on cycles in the xattr structure. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Acked-by: Dave Chinner <dchinner@xxxxxxxxxx> --- libxfs/listxattr.c | 40 +++++++++++++++++++++++----------------- libxfs/listxattr.h | 6 ++++-- repair/pptr.c | 7 ++++++- 3 files changed, 33 insertions(+), 20 deletions(-) diff --git a/libxfs/listxattr.c b/libxfs/listxattr.c index bedaca678..34205682f 100644 --- a/libxfs/listxattr.c +++ b/libxfs/listxattr.c @@ -11,6 +11,7 @@ /* Call a function for every entry in a shortform xattr structure. */ STATIC int xattr_walk_sf( + struct xfs_trans *tp, struct xfs_inode *ip, xattr_walk_fn attr_fn, void *priv) @@ -22,7 +23,7 @@ xattr_walk_sf( sfe = libxfs_attr_sf_firstentry(hdr); for (i = 0; i < hdr->count; i++) { - error = attr_fn(ip, sfe->flags, sfe->nameval, sfe->namelen, + error = attr_fn(tp, ip, sfe->flags, sfe->nameval, sfe->namelen, &sfe->nameval[sfe->namelen], sfe->valuelen, priv); if (error) @@ -37,6 +38,7 @@ xattr_walk_sf( /* Call a function for every entry in this xattr leaf block. */ STATIC int xattr_walk_leaf_entries( + struct xfs_trans *tp, struct xfs_inode *ip, xattr_walk_fn attr_fn, struct xfs_buf *bp, @@ -75,7 +77,7 @@ xattr_walk_leaf_entries( valuelen = be32_to_cpu(name_rmt->valuelen); } - error = attr_fn(ip, entry->flags, name, namelen, value, + error = attr_fn(tp, ip, entry->flags, name, namelen, value, valuelen, priv); if (error) return error; @@ -91,6 +93,7 @@ xattr_walk_leaf_entries( */ STATIC int xattr_walk_leaf( + struct xfs_trans *tp, struct xfs_inode *ip, xattr_walk_fn attr_fn, void *priv) @@ -98,18 +101,19 @@ xattr_walk_leaf( struct xfs_buf *leaf_bp; int error; - error = -libxfs_attr3_leaf_read(NULL, ip, ip->i_ino, 0, &leaf_bp); + error = -libxfs_attr3_leaf_read(tp, ip, ip->i_ino, 0, &leaf_bp); if (error) return error; - error = xattr_walk_leaf_entries(ip, attr_fn, leaf_bp, priv); - libxfs_trans_brelse(NULL, leaf_bp); + error = xattr_walk_leaf_entries(tp, ip, attr_fn, leaf_bp, priv); + libxfs_trans_brelse(tp, leaf_bp); return error; } /* Find the leftmost leaf in the xattr dabtree. */ STATIC int xattr_walk_find_leftmost_leaf( + struct xfs_trans *tp, struct xfs_inode *ip, struct bitmap *seen_blocks, struct xfs_buf **leaf_bpp) @@ -127,7 +131,7 @@ xattr_walk_find_leftmost_leaf( for (;;) { uint16_t magic; - error = -libxfs_da3_node_read(NULL, ip, blkno, &bp, + error = -libxfs_da3_node_read(tp, ip, blkno, &bp, XFS_ATTR_FORK); if (error) return error; @@ -164,7 +168,7 @@ xattr_walk_find_leftmost_leaf( /* Find the next level towards the leaves of the dabtree. */ btree = nodehdr.btree; blkno = be32_to_cpu(btree->before); - libxfs_trans_brelse(NULL, bp); + libxfs_trans_brelse(tp, bp); /* Make sure we haven't seen this new block already. */ if (bitmap_test(seen_blocks, blkno, 1)) @@ -184,13 +188,14 @@ xattr_walk_find_leftmost_leaf( return 0; out_buf: - libxfs_trans_brelse(NULL, bp); + libxfs_trans_brelse(tp, bp); return error; } /* Call a function for every entry in a node-format xattr structure. */ STATIC int xattr_walk_node( + struct xfs_trans *tp, struct xfs_inode *ip, xattr_walk_fn attr_fn, void *priv) @@ -204,12 +209,12 @@ xattr_walk_node( bitmap_alloc(&seen_blocks); - error = xattr_walk_find_leftmost_leaf(ip, seen_blocks, &leaf_bp); + error = xattr_walk_find_leftmost_leaf(tp, ip, seen_blocks, &leaf_bp); if (error) goto out_bitmap; for (;;) { - error = xattr_walk_leaf_entries(ip, attr_fn, leaf_bp, + error = xattr_walk_leaf_entries(tp, ip, attr_fn, leaf_bp, priv); if (error) goto out_leaf; @@ -220,13 +225,13 @@ xattr_walk_node( if (leafhdr.forw == 0) goto out_leaf; - libxfs_trans_brelse(NULL, leaf_bp); + libxfs_trans_brelse(tp, leaf_bp); /* Make sure we haven't seen this new leaf already. */ if (bitmap_test(seen_blocks, leafhdr.forw, 1)) goto out_bitmap; - error = -libxfs_attr3_leaf_read(NULL, ip, ip->i_ino, + error = -libxfs_attr3_leaf_read(tp, ip, ip->i_ino, leafhdr.forw, &leaf_bp); if (error) goto out_bitmap; @@ -238,7 +243,7 @@ xattr_walk_node( } out_leaf: - libxfs_trans_brelse(NULL, leaf_bp); + libxfs_trans_brelse(tp, leaf_bp); out_bitmap: bitmap_free(&seen_blocks); return error; @@ -247,6 +252,7 @@ xattr_walk_node( /* Call a function for every extended attribute in a file. */ int xattr_walk( + struct xfs_trans *tp, struct xfs_inode *ip, xattr_walk_fn attr_fn, void *priv) @@ -257,15 +263,15 @@ xattr_walk( return 0; if (ip->i_af.if_format == XFS_DINODE_FMT_LOCAL) - return xattr_walk_sf(ip, attr_fn, priv); + return xattr_walk_sf(tp, ip, attr_fn, priv); /* attr functions require that the attr fork is loaded */ - error = -libxfs_iread_extents(NULL, ip, XFS_ATTR_FORK); + error = -libxfs_iread_extents(tp, ip, XFS_ATTR_FORK); if (error) return error; if (libxfs_attr_is_leaf(ip)) - return xattr_walk_leaf(ip, attr_fn, priv); + return xattr_walk_leaf(tp, ip, attr_fn, priv); - return xattr_walk_node(ip, attr_fn, priv); + return xattr_walk_node(tp, ip, attr_fn, priv); } diff --git a/libxfs/listxattr.h b/libxfs/listxattr.h index cddd96af7..933e0f529 100644 --- a/libxfs/listxattr.h +++ b/libxfs/listxattr.h @@ -6,10 +6,12 @@ #ifndef __LIBXFS_LISTXATTR_H__ #define __LIBXFS_LISTXATTR_H__ -typedef int (*xattr_walk_fn)(struct xfs_inode *ip, unsigned int attr_flags, +typedef int (*xattr_walk_fn)(struct xfs_trans *tp, struct xfs_inode *ip, + unsigned int attr_flags, const unsigned char *name, unsigned int namelen, const void *value, unsigned int valuelen, void *priv); -int xattr_walk(struct xfs_inode *ip, xattr_walk_fn attr_fn, void *priv); +int xattr_walk(struct xfs_trans *tp, struct xfs_inode *ip, + xattr_walk_fn attr_fn, void *priv); #endif /* __LIBXFS_LISTXATTR_H__ */ diff --git a/repair/pptr.c b/repair/pptr.c index cc66e6372..ee29e47a8 100644 --- a/repair/pptr.c +++ b/repair/pptr.c @@ -593,6 +593,7 @@ store_file_pptr_name( /* Decide if this is a directory parent pointer and stash it if so. */ static int examine_xattr( + struct xfs_trans *tp, struct xfs_inode *ip, unsigned int attr_flags, const unsigned char *name, @@ -1205,6 +1206,7 @@ check_file_parent_ptrs( struct xfs_inode *ip, struct file_scan *fscan) { + struct xfs_trans *tp = NULL; int error; error = -init_slab(&fscan->file_pptr_recs, sizeof(struct file_pptr)); @@ -1215,7 +1217,10 @@ check_file_parent_ptrs( fscan->have_garbage = false; fscan->nr_file_pptrs = 0; - error = xattr_walk(ip, examine_xattr, fscan); + libxfs_trans_alloc_empty(ip->i_mount, &tp); + error = xattr_walk(tp, ip, examine_xattr, fscan); + if (tp) + libxfs_trans_cancel(tp); if (error && !no_modify) do_error(_("ino %llu parent pointer scan failed: %s\n"), (unsigned long long)ip->i_ino,