1 files changed, 128 insertions, 29 deletions

diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 53cc8b986eac..2135b8e67dcc 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -247,14 +247,15 @@ xfs_attr3_leaf_hdr_to_disk(
 	}
 }
 
-static bool
+static xfs_failaddr_t
 xfs_attr3_leaf_verify(
-	struct xfs_buf		*bp)
+	struct xfs_buf			*bp)
 {
-	struct xfs_mount	*mp = bp->b_target->bt_mount;
-	struct xfs_attr_leafblock *leaf = bp->b_addr;
-	struct xfs_perag *pag = bp->b_pag;
-	struct xfs_attr3_icleaf_hdr ichdr;
+	struct xfs_attr3_icleaf_hdr	ichdr;
+	struct xfs_mount		*mp = bp->b_target->bt_mount;
+	struct xfs_attr_leafblock	*leaf = bp->b_addr;
+	struct xfs_perag		*pag = bp->b_pag;
+	struct xfs_attr_leaf_entry	*entries;
 
 	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
 
@@ -262,17 +263,17 @@ xfs_attr3_leaf_verify(
 		struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
 
 		if (ichdr.magic != XFS_ATTR3_LEAF_MAGIC)
-			return false;
+			return __this_address;
 
 		if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_meta_uuid))
-			return false;
+			return __this_address;
 		if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
-			return false;
+			return __this_address;
 		if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->info.lsn)))
-			return false;
+			return __this_address;
 	} else {
 		if (ichdr.magic != XFS_ATTR_LEAF_MAGIC)
-			return false;
+			return __this_address;
 	}
 	/*
 	 * In recovery there is a transient state where count == 0 is valid
@@ -280,12 +281,27 @@ xfs_attr3_leaf_verify(
 	 * if the attr didn't fit in shortform.
 	 */
 	if (pag && pag->pagf_init && ichdr.count == 0)
-		return false;
+		return __this_address;
+
+	/*
+	 * firstused is the block offset of the first name info structure.
+	 * Make sure it doesn't go off the block or crash into the header.
+	 */
+	if (ichdr.firstused > mp->m_attr_geo->blksize)
+		return __this_address;
+	if (ichdr.firstused < xfs_attr3_leaf_hdr_size(leaf))
+		return __this_address;
+
+	/* Make sure the entries array doesn't crash into the name info. */
+	entries = xfs_attr3_leaf_entryp(bp->b_addr);
+	if ((char *)&entries[ichdr.count] >
+	    (char *)bp->b_addr + ichdr.firstused)
+		return __this_address;
 
 	/* XXX: need to range check rest of attr header values */
 	/* XXX: hash order check? */
 
-	return true;
+	return NULL;
 }
 
 static void
@@ -293,12 +309,13 @@ xfs_attr3_leaf_write_verify(
 	struct xfs_buf	*bp)
 {
 	struct xfs_mount	*mp = bp->b_target->bt_mount;
-	struct xfs_buf_log_item	*bip = bp->b_fspriv;
+	struct xfs_buf_log_item	*bip = bp->b_log_item;
 	struct xfs_attr3_leaf_hdr *hdr3 = bp->b_addr;
+	xfs_failaddr_t		fa;
 
-	if (!xfs_attr3_leaf_verify(bp)) {
-		xfs_buf_ioerror(bp, -EFSCORRUPTED);
-		xfs_verifier_error(bp);
+	fa = xfs_attr3_leaf_verify(bp);
+	if (fa) {
+		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 		return;
 	}
 
@@ -322,21 +339,23 @@ xfs_attr3_leaf_read_verify(
 	struct xfs_buf		*bp)
 {
 	struct xfs_mount	*mp = bp->b_target->bt_mount;
+	xfs_failaddr_t		fa;
 
 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
 	     !xfs_buf_verify_cksum(bp, XFS_ATTR3_LEAF_CRC_OFF))
-		xfs_buf_ioerror(bp, -EFSBADCRC);
-	else if (!xfs_attr3_leaf_verify(bp))
-		xfs_buf_ioerror(bp, -EFSCORRUPTED);
-
-	if (bp->b_error)
-		xfs_verifier_error(bp);
+		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
+	else {
+		fa = xfs_attr3_leaf_verify(bp);
+		if (fa)
+			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
+	}
 }
 
 const struct xfs_buf_ops xfs_attr3_leaf_buf_ops = {
 	.name = "xfs_attr3_leaf",
 	.verify_read = xfs_attr3_leaf_read_verify,
 	.verify_write = xfs_attr3_leaf_write_verify,
+	.verify_struct = xfs_attr3_leaf_verify,
 };
 
 int
@@ -735,10 +754,13 @@ xfs_attr_shortform_getvalue(xfs_da_args_t *args)
 }
 
 /*
- * Convert from using the shortform to the leaf.
+ * Convert from using the shortform to the leaf.  On success, return the
+ * buffer so that we can keep it locked until we're totally done with it.
  */
 int
-xfs_attr_shortform_to_leaf(xfs_da_args_t *args)
+xfs_attr_shortform_to_leaf(
+	struct xfs_da_args	*args,
+	struct xfs_buf		**leaf_bp)
 {
 	xfs_inode_t *dp;
 	xfs_attr_shortform_t *sf;
@@ -818,7 +840,7 @@ xfs_attr_shortform_to_leaf(xfs_da_args_t *args)
 		sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
 	}
 	error = 0;
-
+	*leaf_bp = bp;
 out:
 	kmem_free(tmpbuffer);
 	return error;
@@ -867,6 +889,80 @@ xfs_attr_shortform_allfit(
 	return xfs_attr_shortform_bytesfit(dp, bytes);
 }
 
+/* Verify the consistency of an inline attribute fork. */
+xfs_failaddr_t
+xfs_attr_shortform_verify(
+	struct xfs_inode		*ip)
+{
+	struct xfs_attr_shortform	*sfp;
+	struct xfs_attr_sf_entry	*sfep;
+	struct xfs_attr_sf_entry	*next_sfep;
+	char				*endp;
+	struct xfs_ifork		*ifp;
+	int				i;
+	int				size;
+
+	ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_LOCAL);
+	ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
+	sfp = (struct xfs_attr_shortform *)ifp->if_u1.if_data;
+	size = ifp->if_bytes;
+
+	/*
+	 * Give up if the attribute is way too short.
+	 */
+	if (size < sizeof(struct xfs_attr_sf_hdr))
+		return __this_address;
+
+	endp = (char *)sfp + size;
+
+	/* Check all reported entries */
+	sfep = &sfp->list[0];
+	for (i = 0; i < sfp->hdr.count; i++) {
+		/*
+		 * struct xfs_attr_sf_entry has a variable length.
+		 * Check the fixed-offset parts of the structure are
+		 * within the data buffer.
+		 */
+		if (((char *)sfep + sizeof(*sfep)) >= endp)
+			return __this_address;
+
+		/* Don't allow names with known bad length. */
+		if (sfep->namelen == 0)
+			return __this_address;
+
+		/*
+		 * Check that the variable-length part of the structure is
+		 * within the data buffer.  The next entry starts after the
+		 * name component, so nextentry is an acceptable test.
+		 */
+		next_sfep = XFS_ATTR_SF_NEXTENTRY(sfep);
+		if ((char *)next_sfep > endp)
+			return __this_address;
+
+		/*
+		 * Check for unknown flags.  Short form doesn't support
+		 * the incomplete or local bits, so we can use the namespace
+		 * mask here.
+		 */
+		if (sfep->flags & ~XFS_ATTR_NSP_ONDISK_MASK)
+			return __this_address;
+
+		/*
+		 * Check for invalid namespace combinations.  We only allow
+		 * one namespace flag per xattr, so we can just count the
+		 * bits (i.e. hweight) here.
+		 */
+		if (hweight8(sfep->flags & XFS_ATTR_NSP_ONDISK_MASK) > 1)
+			return __this_address;
+
+		sfep = next_sfep;
+	}
+	if ((void *)sfep != (void *)endp)
+		return __this_address;
+
+	return NULL;
+}
+
 /*
  * Convert a leaf attribute list to shortform attribute list
  */
@@ -2170,7 +2266,8 @@ xfs_attr3_leaf_lookup_int(
 	leaf = bp->b_addr;
 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
 	entries = xfs_attr3_leaf_entryp(leaf);
-	ASSERT(ichdr.count < args->geo->blksize / 8);
+	if (ichdr.count >= args->geo->blksize / 8)
+		return -EFSCORRUPTED;
 
 	/*
 	 * Binary search.  (note: small blocks will skip this loop)
@@ -2186,8 +2283,10 @@ xfs_attr3_leaf_lookup_int(
 		else
 			break;
 	}
-	ASSERT(probe >= 0 && (!ichdr.count || probe < ichdr.count));
-	ASSERT(span <= 4 || be32_to_cpu(entry->hashval) == hashval);
+	if (!(probe >= 0 && (!ichdr.count || probe < ichdr.count)))
+		return -EFSCORRUPTED;
+	if (!(span <= 4 || be32_to_cpu(entry->hashval) == hashval))
+		return -EFSCORRUPTED;
 
 	/*
 	 * Since we may have duplicate hashval's, find the first matching