From 970e4936d7d15f35d00fd15a14f5343ba78b2fc8 Mon Sep 17 00:00:00 2001 From: Joel Becker Date: Thu, 13 Nov 2008 14:49:19 -0800 Subject: ocfs2: Validate metadata only when it's read from disk. Add an optional validation hook to ocfs2_read_blocks(). Now the validation function is only called when a block was actually read off of disk. It is not called when the buffer was in cache. We add a buffer state bit BH_NeedsValidate to flag these buffers. It must always be one higher than the last JBD2 buffer state bit. The dinode, dirblock, extent_block, and xattr_block validators are lifted to this scheme directly. The group_descriptor validator needs to be split into two pieces. The first part only needs the gd buffer and is passed to ocfs2_read_block(). The second part requires the dinode as well, and is called every time. It's only 3 compares, so it's tiny. This also allows us to clean up the non-fatal gd check used by resize.c. It now has no magic argument. Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh --- fs/ocfs2/suballoc.c | 91 +++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 64 insertions(+), 27 deletions(-) (limited to 'fs/ocfs2/suballoc.c') diff --git a/fs/ocfs2/suballoc.c b/fs/ocfs2/suballoc.c index 766a00b26441..226fe21f2608 100644 --- a/fs/ocfs2/suballoc.c +++ b/fs/ocfs2/suballoc.c @@ -145,14 +145,6 @@ static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl) return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc); } -int ocfs2_validate_group_descriptor(struct super_block *sb, - struct ocfs2_dinode *di, - struct buffer_head *bh, - int clean_error) -{ - unsigned int max_bits; - struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data; - #define do_error(fmt, ...) \ do{ \ if (clean_error) \ @@ -161,6 +153,12 @@ int ocfs2_validate_group_descriptor(struct super_block *sb, ocfs2_error(sb, fmt, ##__VA_ARGS__); \ } while (0) +static int ocfs2_validate_gd_self(struct super_block *sb, + struct buffer_head *bh, + int clean_error) +{ + struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data; + if (!OCFS2_IS_VALID_GROUP_DESC(gd)) { do_error("Group descriptor #%llu has bad signature %.*s", (unsigned long long)bh->b_blocknr, 7, @@ -184,6 +182,35 @@ int ocfs2_validate_group_descriptor(struct super_block *sb, return -EINVAL; } + if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) { + do_error("Group descriptor #%llu has bit count %u but " + "claims that %u are free", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(gd->bg_bits), + le16_to_cpu(gd->bg_free_bits_count)); + return -EINVAL; + } + + if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) { + do_error("Group descriptor #%llu has bit count %u but " + "max bitmap bits of %u", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(gd->bg_bits), + 8 * le16_to_cpu(gd->bg_size)); + return -EINVAL; + } + + return 0; +} + +static int ocfs2_validate_gd_parent(struct super_block *sb, + struct ocfs2_dinode *di, + struct buffer_head *bh, + int clean_error) +{ + unsigned int max_bits; + struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data; + if (di->i_blkno != gd->bg_parent_dinode) { do_error("Group descriptor #%llu has bad parent " "pointer (%llu, expected %llu)", @@ -209,26 +236,35 @@ int ocfs2_validate_group_descriptor(struct super_block *sb, return -EINVAL; } - if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) { - do_error("Group descriptor #%llu has bit count %u but " - "claims that %u are free", - (unsigned long long)bh->b_blocknr, - le16_to_cpu(gd->bg_bits), - le16_to_cpu(gd->bg_free_bits_count)); - return -EINVAL; - } + return 0; +} - if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) { - do_error("Group descriptor #%llu has bit count %u but " - "max bitmap bits of %u", - (unsigned long long)bh->b_blocknr, - le16_to_cpu(gd->bg_bits), - 8 * le16_to_cpu(gd->bg_size)); - return -EINVAL; - } #undef do_error - return 0; +/* + * This version only prints errors. It does not fail the filesystem, and + * exists only for resize. + */ +int ocfs2_check_group_descriptor(struct super_block *sb, + struct ocfs2_dinode *di, + struct buffer_head *bh) +{ + int rc; + + rc = ocfs2_validate_gd_self(sb, bh, 1); + if (!rc) + rc = ocfs2_validate_gd_parent(sb, di, bh, 1); + + return rc; +} + +static int ocfs2_validate_group_descriptor(struct super_block *sb, + struct buffer_head *bh) +{ + mlog(0, "Validating group descriptor %llu\n", + (unsigned long long)bh->b_blocknr); + + return ocfs2_validate_gd_self(sb, bh, 0); } int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di, @@ -237,11 +273,12 @@ int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di, int rc; struct buffer_head *tmp = *bh; - rc = ocfs2_read_block(inode, gd_blkno, &tmp); + rc = ocfs2_read_block(inode, gd_blkno, &tmp, + ocfs2_validate_group_descriptor); if (rc) goto out; - rc = ocfs2_validate_group_descriptor(inode->i_sb, di, tmp, 0); + rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0); if (rc) { brelse(tmp); goto out; -- cgit v1.2.3