From: "Darrick J. Wong" <djwong@us.ibm.com>
To: Andreas Dilger <adilger.kernel@dilger.ca>,
Theodore Tso <tytso@mit.edu>,
"Darrick J. Wong" <djwong@us.ibm.com>
Cc: Sunil Mushran <sunil.mushran@oracle.com>,
Amir Goldstein <amir73il@gmail.com>,
linux-kernel <linux-kernel@vger.kernel.org>,
Andi Kleen <andi@firstfloor.org>, Mingming Cao <cmm@us.ibm.com>,
Joel Becker <jlbec@evilplan.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-ext4@vger.kernel.org, Coly Li <colyli@gmail.com>
Subject: [PATCH 13/16] ext4: Calculate and verify checksums of extended attribute blocks
Date: Wed, 31 Aug 2011 17:32:00 -0700 [thread overview]
Message-ID: <20110901003200.31048.70117.stgit@elm3c44.beaverton.ibm.com> (raw)
In-Reply-To: <20110901003030.31048.99467.stgit@elm3c44.beaverton.ibm.com>
Calculate and verify the checksums of extended attribute blocks. This only
applies to separate EA blocks that are pointed to by inode->i_file_acl (i.e.
external EA blocks); the checksum lives in the EA header.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
---
fs/ext4/xattr.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++---------
fs/ext4/xattr.h | 3 +-
2 files changed, 76 insertions(+), 15 deletions(-)
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index c757adc..2825e59 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -56,6 +56,7 @@
#include <linux/mbcache.h>
#include <linux/quotaops.h>
#include <linux/rwsem.h>
+#include <linux/crc32c.h>
#include "ext4_jbd2.h"
#include "ext4.h"
#include "xattr.h"
@@ -122,6 +123,58 @@ const struct xattr_handler *ext4_xattr_handlers[] = {
NULL
};
+static __le32 ext4_xattr_block_csum(struct inode *inode,
+ sector_t block_nr,
+ struct ext4_xattr_header *hdr)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ int offset = offsetof(struct ext4_xattr_header, h_checksum);
+ __u32 crc = 0;
+
+ if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ block_nr = cpu_to_le64(block_nr);
+ crc = crc32c_le(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
+ crc = crc32c_le(crc, (__u8 *)&block_nr, sizeof(block_nr));
+ crc = crc32c_le(crc, (__u8 *)hdr, offset);
+ offset += sizeof(hdr->h_checksum); /* skip checksum */
+ crc = crc32c_le(crc, (__u8 *)hdr + offset,
+ EXT4_BLOCK_SIZE(inode->i_sb) - offset);
+ return cpu_to_le32(crc);
+}
+
+static int ext4_xattr_block_csum_verify(struct inode *inode,
+ sector_t block_nr,
+ struct ext4_xattr_header *hdr)
+{
+ if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
+ (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr)))
+ return 0;
+ return 1;
+}
+
+static void ext4_xattr_block_csum_set(struct inode *inode,
+ sector_t block_nr,
+ struct ext4_xattr_header *hdr)
+{
+ if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return;
+
+ hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr);
+}
+
+static inline int ext4_handle_dirty_xattr_block(handle_t *handle,
+ struct inode *inode,
+ struct buffer_head *bh)
+{
+ ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh));
+ return ext4_handle_dirty_metadata(handle, inode, bh);
+}
+
static inline const struct xattr_handler *
ext4_xattr_handler(int name_index)
{
@@ -156,14 +209,21 @@ ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end)
}
static inline int
-ext4_xattr_check_block(struct buffer_head *bh)
+ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh)
{
int error;
+ if (buffer_verified(bh))
+ return 0;
+
if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
BHDR(bh)->h_blocks != cpu_to_le32(1))
return -EIO;
+ if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh)))
+ return -EIO;
error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size);
+ if (!error)
+ set_buffer_verified(bh);
return error;
}
@@ -226,7 +286,7 @@ ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
goto cleanup;
ea_bdebug(bh, "b_count=%d, refcount=%d",
atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
- if (ext4_xattr_check_block(bh)) {
+ if (ext4_xattr_check_block(inode, bh)) {
bad_block:
EXT4_ERROR_INODE(inode, "bad block %llu",
EXT4_I(inode)->i_file_acl);
@@ -370,7 +430,7 @@ ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size)
goto cleanup;
ea_bdebug(bh, "b_count=%d, refcount=%d",
atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
- if (ext4_xattr_check_block(bh)) {
+ if (ext4_xattr_check_block(inode, bh)) {
EXT4_ERROR_INODE(inode, "bad block %llu",
EXT4_I(inode)->i_file_acl);
error = -EIO;
@@ -489,7 +549,7 @@ ext4_xattr_release_block(handle_t *handle, struct inode *inode,
EXT4_FREE_BLOCKS_FORGET);
} else {
le32_add_cpu(&BHDR(bh)->h_refcount, -1);
- error = ext4_handle_dirty_metadata(handle, inode, bh);
+ error = ext4_handle_dirty_xattr_block(handle, inode, bh);
if (IS_SYNC(inode))
ext4_handle_sync(handle);
dquot_free_block(inode, 1);
@@ -662,7 +722,7 @@ ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i,
ea_bdebug(bs->bh, "b_count=%d, refcount=%d",
atomic_read(&(bs->bh->b_count)),
le32_to_cpu(BHDR(bs->bh)->h_refcount));
- if (ext4_xattr_check_block(bs->bh)) {
+ if (ext4_xattr_check_block(inode, bs->bh)) {
EXT4_ERROR_INODE(inode, "bad block %llu",
EXT4_I(inode)->i_file_acl);
error = -EIO;
@@ -725,9 +785,9 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode,
if (error == -EIO)
goto bad_block;
if (!error)
- error = ext4_handle_dirty_metadata(handle,
- inode,
- bs->bh);
+ error = ext4_handle_dirty_xattr_block(handle,
+ inode,
+ bs->bh);
if (error)
goto cleanup;
goto inserted;
@@ -796,9 +856,9 @@ inserted:
ea_bdebug(new_bh, "reusing; refcount now=%d",
le32_to_cpu(BHDR(new_bh)->h_refcount));
unlock_buffer(new_bh);
- error = ext4_handle_dirty_metadata(handle,
- inode,
- new_bh);
+ error = ext4_handle_dirty_xattr_block(handle,
+ inode,
+ new_bh);
if (error)
goto cleanup_dquot;
}
@@ -848,8 +908,8 @@ getblk_failed:
set_buffer_uptodate(new_bh);
unlock_buffer(new_bh);
ext4_xattr_cache_insert(new_bh);
- error = ext4_handle_dirty_metadata(handle,
- inode, new_bh);
+ error = ext4_handle_dirty_xattr_block(handle,
+ inode, new_bh);
if (error)
goto cleanup;
}
@@ -1190,7 +1250,7 @@ retry:
error = -EIO;
if (!bh)
goto cleanup;
- if (ext4_xattr_check_block(bh)) {
+ if (ext4_xattr_check_block(inode, bh)) {
EXT4_ERROR_INODE(inode, "bad block %llu",
EXT4_I(inode)->i_file_acl);
error = -EIO;
diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h
index 25b7387..b2b20af 100644
--- a/fs/ext4/xattr.h
+++ b/fs/ext4/xattr.h
@@ -27,7 +27,8 @@ struct ext4_xattr_header {
__le32 h_refcount; /* reference count */
__le32 h_blocks; /* number of disk blocks used */
__le32 h_hash; /* hash value of all attributes */
- __u32 h_reserved[4]; /* zero right now */
+ __le32 h_checksum; /* crc32c(uuid+inum+xattrblock) */
+ __u32 h_reserved[3]; /* zero right now */
};
struct ext4_xattr_ibody_header {
next prev parent reply other threads:[~2011-09-01 0:32 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-01 0:30 [PATCH v1 00/16] ext4: Add metadata checksumming Darrick J. Wong
2011-09-01 0:30 ` [PATCH 01/16] ext4: ext4_dx_add_entry should dirty directory metadata with the directory inode Darrick J. Wong
2011-09-01 0:30 ` [PATCH 02/16] ext4: ext4_rename should dirty dir_bh with the correct directory Darrick J. Wong
2011-09-01 0:30 ` [PATCH 03/16] ext4: ext4_mkdir should dirty dir_block with the parent inode Darrick J. Wong
2011-09-01 0:30 ` [PATCH 04/16] ext4: Create a new BH_Verified flag to avoid unnecessary metadata validation Darrick J. Wong
2011-09-01 0:31 ` [PATCH 05/16] ext4: Create a rocompat flag for extended metadata checksumming Darrick J. Wong
2011-09-01 0:31 ` [PATCH 06/16] ext4: Calculate and verify inode checksums Darrick J. Wong
2011-09-01 2:30 ` Andreas Dilger
2011-09-02 19:32 ` Darrick J. Wong
2011-09-02 22:02 ` Andreas Dilger
2011-09-05 17:57 ` Darrick J. Wong
2011-09-01 0:31 ` [PATCH 07/16] ext4: Create bitmap checksum helper functions Darrick J. Wong
2011-09-01 0:31 ` [PATCH 08/16] ext4: Calculate and verify checksums for inode bitmaps Darrick J. Wong
2011-09-01 4:49 ` Andreas Dilger
2011-09-02 19:18 ` Darrick J. Wong
2011-09-02 21:27 ` Andreas Dilger
2011-09-05 18:22 ` Darrick J. Wong
2011-09-05 18:27 ` Andi Kleen
2011-09-05 19:45 ` James Bottomley
2011-09-05 22:12 ` Darrick J. Wong
2011-09-01 0:31 ` [PATCH 09/16] ext4: Calculate and verify block bitmap checksum Darrick J. Wong
[not found] ` <2492E720-3316-4561-8C9C-BBC6E8670EAD@dilger.ca>
2011-09-02 19:08 ` Darrick J. Wong
2011-09-02 21:06 ` Andreas Dilger
2011-09-01 0:31 ` [PATCH 10/16] ext4: Verify and calculate checksums for extent tree blocks Darrick J. Wong
[not found] ` <26584BE9-B716-40D5-B3B4-8C5912869648@dilger.ca>
2011-09-02 19:02 ` Darrick J. Wong
2011-09-01 0:31 ` [PATCH 11/16] ext4: Calculate and verify checksums for htree nodes Darrick J. Wong
2011-09-01 0:31 ` [PATCH 12/16] ext4: Calculate and verify checksums of directory leaf blocks Darrick J. Wong
[not found] ` <4D5D8FB2-0D8A-4D30-B6D8-51158395C1C9@dilger.ca>
2011-09-02 18:57 ` Darrick J. Wong
2011-09-02 20:52 ` Andreas Dilger
2011-09-05 18:30 ` Darrick J. Wong
2011-09-01 0:32 ` Darrick J. Wong [this message]
[not found] ` <F4A42DCE-F91C-419B-9153-65A7EA91D241@dilger.ca>
2011-09-02 18:43 ` [PATCH 13/16] ext4: Calculate and verify checksums of extended attribute blocks Darrick J. Wong
2011-09-01 0:32 ` [PATCH 14/16] ext4: Make inode checksum cover empty space Darrick J. Wong
[not found] ` <4540D5DB-53D9-4C33-BC6B-868870D42AF3@dilger.ca>
2011-09-02 18:42 ` Darrick J. Wong
2011-09-01 0:32 ` [PATCH 15/16] ext4: Calculate and verify superblock checksum Darrick J. Wong
[not found] ` <2882FBB2-797C-4D27-8569-B6826DD34F68@dilger.ca>
2011-09-02 18:40 ` Darrick J. Wong
2011-09-01 0:32 ` [PATCH 16/16] jbd2: Support CRC32C transaction checksums Darrick J. Wong
[not found] ` <99019900-30B1-450A-9620-E94371A30CC6@dilger.ca>
2011-09-02 18:31 ` Darrick J. Wong
2011-09-02 14:15 ` [PATCH v1 00/16] ext4: Add metadata checksumming Greg Freemyer
2011-09-02 18:22 ` Darrick J. Wong
2011-09-04 11:41 ` Martin K. Petersen
2011-09-04 16:54 ` Andi Kleen
2011-09-04 17:17 ` Martin K. Petersen
2011-09-04 17:44 ` Andi Kleen
2011-09-04 22:19 ` Martin K. Petersen
2011-09-05 18:55 ` Darrick J. Wong
2011-09-05 18:45 ` Darrick J. Wong
2011-09-06 12:59 ` Martin K. Petersen
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