xfs_metadump: obfuscate attrs on CRC fs

PATCH In review Eric Sandeen 3 participants 3 messages Jun 12, 2015 – Jun 25, 2015

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Eric Sandeen

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2015-06-12 22:50 UTC #0 lore raw

PATCH 1/1 xfs_metadump: obfuscate attrs on CRC fs

Lots of issues in xfs_metadump obfuscation of extended attributes with CRC filesystems; this fixes it up.

The main issues are that the headers differ, and the space in the remote blocks differ.

Tested with a script I'm using to do other metadump work; I still owe an xfstest for this and other bits.

Signed-off-by Eric Sandeen <[email protected]>

---

Brief/hacky testcase; populate w/ many attr types with:

MNTPT=/mount/test

# FMT_LOCAL
touch $MNTPT/S_IFREG.ATTR.FMT_LOCAL
setfattr -n user.localattrname -v localattrvalue $MNTPT/S_IFREG.ATTR.FMT_LOCAL

# FMT_EXTENTS
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS
for I in seq 1 50; do
setfattr -n user.extentattrname$I -v extentattrvalue $MNTPT/S_IFREG.ATTR.FMT_EXTENTS
done

# FMT_EXTENTS with a single remote 3k value, fill with "C"
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE3K
xfs_io -f -c "pwrite -S 0x43 0 3k" attrvalfile &>/dev/null
attr -q -s user.remotebtreeattrname $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE3K < attrvalfile

# FMT_EXTENTS with a single remote 4k value, fill with "D"
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE4K
xfs_io -f -c "pwrite -S 0x44 0 4k" attrvalfile &>/dev/null
attr -q -s user.remotebtreeattrname $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE4K < attrvalfile

# FMT_BTREE
touch $MNTPT/S_IFREG.ATTR.FMT_BTREE
for I in seq 1 1000; do
setfattr -n user.btreeattrname$I -v btreelongerattrvalue $MNTPT/S_IFREG.ATTR.FMT_BTREE
done

on a crc filesystem, an obfuscated metadump will show all these attrs in the clear with getfattr -dR $MNTPT

db/metadump.c +29 ~~-14~~

index 94f92bc..793f39e 100644
@@ -1268,39 +1268,54 @@ add_remote_vals(
 	}
 }
 
+/* Handle remote and leaf attributes */
 static void
 obfuscate_attr_block(
-	char			*block,
-	xfs_fileoff_t		offset)
+	char				*block,
+	xfs_fileoff_t			offset)
 {
-	xfs_attr_leafblock_t	*leaf;
-	int			i;
-	int			nentries;
-	xfs_attr_leaf_entry_t 	*entry;
-	xfs_attr_leaf_name_local_t *local;
-	xfs_attr_leaf_name_remote_t *remote;
+	struct xfs_attr_leafblock	*leaf;
+	struct xfs_attr3_icleaf_hdr	hdr;
+	int				i;
+	int				nentries;
+	xfs_attr_leaf_entry_t 		*entry;
+	xfs_attr_leaf_name_local_t 	*local;
+	xfs_attr_leaf_name_remote_t 	*remote;
+	__uint32_t			bs = mp->m_sb.sb_blocksize;
+
 
 	leaf = (xfs_attr_leafblock_t *)block;
 
-	if (be16_to_cpu(leaf->hdr.info.magic) != XFS_ATTR_LEAF_MAGIC) {
+	/* Get header; accounts for crc & non-crc */
+	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &hdr, leaf);
+
+	/* Remote attributes */
+	if ((hdr.magic != XFS_ATTR_LEAF_MAGIC) &&
+	    (hdr.magic != XFS_ATTR3_LEAF_MAGIC)) {
 		for (i = 0; i < attr_data.remote_val_count; i++) {
-			/* XXX: need to handle CRC headers */
 			if (attr_data.remote_vals[i] == offset)
-				memset(block, 0, mp->m_sb.sb_blocksize);
+				/* magic to handle attr and attr3 */
+				memset(block +
+					(bs - XFS_ATTR3_RMT_BUF_SPACE(mp, bs)),
+				      0, XFS_ATTR3_RMT_BUF_SPACE(mp, bs));
 		}
 		return;
 	}
 
-	nentries = be16_to_cpu(leaf->hdr.count);
+	nentries = hdr.count;
+
 	if (nentries * sizeof(xfs_attr_leaf_entry_t) +
-			sizeof(xfs_attr_leaf_hdr_t) > mp->m_sb.sb_blocksize) {
+			xfs_attr3_leaf_hdr_size(leaf) >
+				XFS_ATTR3_RMT_BUF_SPACE(mp, bs)) {
 		if (show_warnings)
 			print_warning("invalid attr count in inode %llu",
 					(long long)cur_ino);
 		return;
 	}
 
-	for (i = 0, entry = &leaf->entries[0]; i < nentries; i++, entry++) {
+	entry = xfs_attr3_leaf_entryp(leaf);
+
+	for (i = 0; i < nentries; i++, entry++) {
 		if (be16_to_cpu(entry->nameidx) > mp->m_sb.sb_blocksize) {
 			if (show_warnings)
 				print_warning(

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Brian Foster

2015-06-19 13:19 UTC #1 lore raw

Quoted 73 lines · Eric Sandeen

Lots of issues in xfs_metadump obfuscation of extended attributes with CRC filesystems; this fixes it up.
The main issues are that the headers differ, and the space in the remote blocks differ.
Tested with a script I'm using to do other metadump work; I still owe an xfstest for this and other bits.
Signed-off-by Eric Sandeen <[email protected]>
---
Brief/hacky testcase; populate w/ many attr types with:
MNTPT=/mount/test
# FMT_LOCAL
touch $MNTPT/S_IFREG.ATTR.FMT_LOCAL
setfattr -n user.localattrname -v localattrvalue $MNTPT/S_IFREG.ATTR.FMT_LOCAL
# FMT_EXTENTS
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS
for I in seq 1 50; do
setfattr -n user.extentattrname$I -v extentattrvalue $MNTPT/S_IFREG.ATTR.FMT_EXTENTS
done
# FMT_EXTENTS with a single remote 3k value, fill with "C"
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE3K
xfs_io -f -c "pwrite -S 0x43 0 3k" attrvalfile &>/dev/null
attr -q -s user.remotebtreeattrname $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE3K < attrvalfile
# FMT_EXTENTS with a single remote 4k value, fill with "D"
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE4K
xfs_io -f -c "pwrite -S 0x44 0 4k" attrvalfile &>/dev/null
attr -q -s user.remotebtreeattrname $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE4K < attrvalfile
# FMT_BTREE
touch $MNTPT/S_IFREG.ATTR.FMT_BTREE
for I in seq 1 1000; do
setfattr -n user.btreeattrname$I -v btreelongerattrvalue $MNTPT/S_IFREG.ATTR.FMT_BTREE
done
on a crc filesystem, an obfuscated metadump will show all these attrs in the clear with getfattr -dR $MNTPT
db/metadump.c +9 -8
index 94f92bc..793f39e 100644
@@ -1268,39 +1268,54 @@ add_remote_vals(
 	}
 }
 
+/* Handle remote and leaf attributes */
 static void
 obfuscate_attr_block(
-	char			*block,
-	xfs_fileoff_t		offset)
+	char				*block,
+	xfs_fileoff_t			offset)
 {
-	xfs_attr_leafblock_t	*leaf;
-	int			i;
-	int			nentries;
-	xfs_attr_leaf_entry_t 	*entry;
-	xfs_attr_leaf_name_local_t *local;
-	xfs_attr_leaf_name_remote_t *remote;
+	struct xfs_attr_leafblock	*leaf;
+	struct xfs_attr3_icleaf_hdr	hdr;
+	int				i;
+	int				nentries;
+	xfs_attr_leaf_entry_t 		*entry;
+	xfs_attr_leaf_name_local_t 	*local;

db/metadump.c add_remote_vals( · line 1291

Quoted 10 lines

db/metadump.c +6 -1

+	xfs_attr_leaf_name_remote_t 	*remote;
+	__uint32_t			bs = mp->m_sb.sb_blocksize;
+
 
 	leaf = (xfs_attr_leafblock_t *)block;
 
-	if (be16_to_cpu(leaf->hdr.info.magic) != XFS_ATTR_LEAF_MAGIC) {
+	/* Get header; accounts for crc & non-crc */
+	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &hdr, leaf);
+

The above conversion helper assert fails on a non-leaf magic. It seems like effectively the same check below with this change, but it might be more appropriate to defer the leaf header conversion to after the hunk below..?

Brian

Quoted 36 lines

db/metadump.c +14 -5

+	/* Remote attributes */
+	if ((hdr.magic != XFS_ATTR_LEAF_MAGIC) &&
+	    (hdr.magic != XFS_ATTR3_LEAF_MAGIC)) {
 		for (i = 0; i < attr_data.remote_val_count; i++) {
-			/* XXX: need to handle CRC headers */
 			if (attr_data.remote_vals[i] == offset)
-				memset(block, 0, mp->m_sb.sb_blocksize);
+				/* magic to handle attr and attr3 */
+				memset(block +
+					(bs - XFS_ATTR3_RMT_BUF_SPACE(mp, bs)),
+				      0, XFS_ATTR3_RMT_BUF_SPACE(mp, bs));
 		}
 		return;
 	}
 
-	nentries = be16_to_cpu(leaf->hdr.count);
+	nentries = hdr.count;
+
 	if (nentries * sizeof(xfs_attr_leaf_entry_t) +
-			sizeof(xfs_attr_leaf_hdr_t) > mp->m_sb.sb_blocksize) {
+			xfs_attr3_leaf_hdr_size(leaf) >
+				XFS_ATTR3_RMT_BUF_SPACE(mp, bs)) {
 		if (show_warnings)
 			print_warning("invalid attr count in inode %llu",
 					(long long)cur_ino);
 		return;
 	}
 
-	for (i = 0, entry = &leaf->entries[0]; i < nentries; i++, entry++) {
+	entry = xfs_attr3_leaf_entryp(leaf);
+
+	for (i = 0; i < nentries; i++, entry++) {
 		if (be16_to_cpu(entry->nameidx) > mp->m_sb.sb_blocksize) {
 			if (show_warnings)
 				print_warning(

Quoted 4 lines

_______________________________________________
xfs mailing list
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http://oss.sgi.com/mailman/listinfo/xfs

_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs

Eric Sandeen

2015-06-25 20:57 UTC #2 lore raw

In reply to Eric Sandeen

Quoted 10 lines · Eric Sandeen

Lots of issues in xfs_metadump obfuscation of extended attributes with CRC filesystems; this fixes it up.
The main issues are that the headers differ, and the space in the remote blocks differ.
Tested with a script I'm using to do other metadump work; I still owe an xfstest for this and other bits.
Signed-off-by Eric Sandeen <[email protected]>

Self-NAK on this for now, getting some unexpected weirdness when I enable warnings in metadump.

-Eric

Quoted 109 lines

---
Brief/hacky testcase; populate w/ many attr types with:
MNTPT=/mount/test
# FMT_LOCAL
touch $MNTPT/S_IFREG.ATTR.FMT_LOCAL
setfattr -n user.localattrname -v localattrvalue $MNTPT/S_IFREG.ATTR.FMT_LOCAL
# FMT_EXTENTS
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS
for I in seq 1 50; do
setfattr -n user.extentattrname$I -v extentattrvalue $MNTPT/S_IFREG.ATTR.FMT_EXTENTS
done
# FMT_EXTENTS with a single remote 3k value, fill with "C"
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE3K
xfs_io -f -c "pwrite -S 0x43 0 3k" attrvalfile &>/dev/null
attr -q -s user.remotebtreeattrname $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE3K < attrvalfile
# FMT_EXTENTS with a single remote 4k value, fill with "D"
touch $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE4K
xfs_io -f -c "pwrite -S 0x44 0 4k" attrvalfile &>/dev/null
attr -q -s user.remotebtreeattrname $MNTPT/S_IFREG.ATTR.FMT_EXTENTS_REMOTE4K < attrvalfile
# FMT_BTREE
touch $MNTPT/S_IFREG.ATTR.FMT_BTREE
for I in seq 1 1000; do
setfattr -n user.btreeattrname$I -v btreelongerattrvalue $MNTPT/S_IFREG.ATTR.FMT_BTREE
done
on a crc filesystem, an obfuscated metadump will show all these attrs in the clear with getfattr -dR $MNTPT
db/metadump.c +29 ~~-14~~
index 94f92bc..793f39e 100644
@@ -1268,39 +1268,54 @@ add_remote_vals(
 	}
 }
 
+/* Handle remote and leaf attributes */
 static void
 obfuscate_attr_block(
-	char			*block,
-	xfs_fileoff_t		offset)
+	char				*block,
+	xfs_fileoff_t			offset)
 {
-	xfs_attr_leafblock_t	*leaf;
-	int			i;
-	int			nentries;
-	xfs_attr_leaf_entry_t 	*entry;
-	xfs_attr_leaf_name_local_t *local;
-	xfs_attr_leaf_name_remote_t *remote;
+	struct xfs_attr_leafblock	*leaf;
+	struct xfs_attr3_icleaf_hdr	hdr;
+	int				i;
+	int				nentries;
+	xfs_attr_leaf_entry_t 		*entry;
+	xfs_attr_leaf_name_local_t 	*local;
+	xfs_attr_leaf_name_remote_t 	*remote;
+	__uint32_t			bs = mp->m_sb.sb_blocksize;
+
 
 	leaf = (xfs_attr_leafblock_t *)block;
 
-	if (be16_to_cpu(leaf->hdr.info.magic) != XFS_ATTR_LEAF_MAGIC) {
+	/* Get header; accounts for crc & non-crc */
+	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &hdr, leaf);
+
+	/* Remote attributes */
+	if ((hdr.magic != XFS_ATTR_LEAF_MAGIC) &&
+	    (hdr.magic != XFS_ATTR3_LEAF_MAGIC)) {
 		for (i = 0; i < attr_data.remote_val_count; i++) {
-			/* XXX: need to handle CRC headers */
 			if (attr_data.remote_vals[i] == offset)
-				memset(block, 0, mp->m_sb.sb_blocksize);
+				/* magic to handle attr and attr3 */
+				memset(block +
+					(bs - XFS_ATTR3_RMT_BUF_SPACE(mp, bs)),
+				      0, XFS_ATTR3_RMT_BUF_SPACE(mp, bs));
 		}
 		return;
 	}
 
-	nentries = be16_to_cpu(leaf->hdr.count);
+	nentries = hdr.count;
+
 	if (nentries * sizeof(xfs_attr_leaf_entry_t) +
-			sizeof(xfs_attr_leaf_hdr_t) > mp->m_sb.sb_blocksize) {
+			xfs_attr3_leaf_hdr_size(leaf) >
+				XFS_ATTR3_RMT_BUF_SPACE(mp, bs)) {
 		if (show_warnings)
 			print_warning("invalid attr count in inode %llu",
 					(long long)cur_ino);
 		return;
 	}
 
-	for (i = 0, entry = &leaf->entries[0]; i < nentries; i++, entry++) {
+	entry = xfs_attr3_leaf_entryp(leaf);
+
+	for (i = 0; i < nentries; i++, entry++) {
 		if (be16_to_cpu(entry->nameidx) > mp->m_sb.sb_blocksize) {
 			if (show_warnings)
 				print_warning(

Quoted 5 lines

_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs

_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs