When recovering a journal with checksum v2, verify the commit block checksum. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> --- e2fsck/recovery.c | 33 +++++++++++++++++++++++++++++++++ lib/ext2fs/kernel-jbd.h | 11 +++++++++++ 2 files changed, 44 insertions(+), 0 deletions(-) diff --git a/e2fsck/recovery.c b/e2fsck/recovery.c index a192378..beafacc 100644 --- a/e2fsck/recovery.c +++ b/e2fsck/recovery.c @@ -375,6 +375,26 @@ static int calc_chksums(journal_t *journal, struct buffer_head *bh, return 0; } +static int jbd2_commit_block_csum_verify(journal_t *j, void *buf) +{ + struct commit_header *h; + __u32 provided, calculated; + + if (!JFS_HAS_INCOMPAT_FEATURE(j, JFS_FEATURE_INCOMPAT_CSUM_V2)) + return 1; + + h = buf; + provided = h->h_chksum[0]; + h->h_chksum[0] = 0; + calculated = ext2fs_crc32c_le(~0, j->j_superblock->s_uuid, + sizeof(j->j_superblock->s_uuid)); + calculated = ext2fs_crc32c_le(calculated, buf, j->j_blocksize); + h->h_chksum[0] = provided; + + provided = ext2fs_be32_to_cpu(provided); + return provided == calculated; +} + static int do_one_pass(journal_t *journal, struct recovery_info *info, enum passtype pass) { @@ -696,6 +716,19 @@ static int do_one_pass(journal_t *journal, } crc32_sum = ~0; } + if (pass == PASS_SCAN && + !jbd2_commit_block_csum_verify(journal, + bh->b_data)) { + info->end_transaction = next_commit_ID; + + if (!JFS_HAS_INCOMPAT_FEATURE(journal, + JFS_FEATURE_INCOMPAT_ASYNC_COMMIT)) { + journal->j_failed_commit = + next_commit_ID; + brelse(bh); + break; + } + } brelse(bh); next_commit_ID++; continue; diff --git a/lib/ext2fs/kernel-jbd.h b/lib/ext2fs/kernel-jbd.h index b79eed5..c650582 100644 --- a/lib/ext2fs/kernel-jbd.h +++ b/lib/ext2fs/kernel-jbd.h @@ -121,6 +121,17 @@ typedef struct journal_header_s #define JBD2_CHECKSUM_BYTES (32 / sizeof(__u32)) /* * Commit block header for storing transactional checksums: + * + * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum* + * fields are used to store a checksum of the descriptor and data blocks. + * + * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum + * field is used to store crc32c(uuid+commit_block). Each journal metadata + * block gets its own checksum, and data block checksums are stored in + * journal_block_tag (in the descriptor). The other h_chksum* fields are + * not used. + * + * Checksum v1 and v2 are mutually exclusive features. */ struct commit_header { __u32 h_magic; -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html