| Message ID | 20130927000334.17889.54958.stgit@birch.djwong.org |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Sep 26, 2013 at 05:03:34PM -0700, Darrick J. Wong wrote: > Perform a quick sanity check of bitmap and inode table block numbers when > loading them, and if there's something suspicious, mark the block group > corrupt. > > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> > --- > fs/ext4/balloc.c | 5 +++++ > fs/ext4/ext4.h | 2 ++ > fs/ext4/ialloc.c | 4 ++++ > fs/ext4/inode.c | 6 ++++++ > fs/ext4/super.c | 21 +++++++++++++++++++++ > 5 files changed, 38 insertions(+) > > > diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c > index 4390f9f..3d79bfe 100644 > --- a/fs/ext4/balloc.c > +++ b/fs/ext4/balloc.c > @@ -396,11 +396,16 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) > struct ext4_group_desc *desc; > struct buffer_head *bh; > ext4_fsblk_t bitmap_blk; > + struct ext4_group_info *grp; > > desc = ext4_get_group_desc(sb, block_group, NULL); > if (!desc) > return NULL; > bitmap_blk = ext4_block_bitmap(sb, desc); > + if (!ext4_is_sane_bgdata_location(sb, block_group, bitmap_blk)) { > + grp = ext4_get_group_info(sb, block_group); > + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); Why don't return NULL directly? If we found that the location of bitmap is insane, we shouldn't read this bitmap. - Zheng > + } > bh = sb_getblk(sb, bitmap_blk); > if (unlikely(!bh)) { > ext4_error(sb, "Cannot get buffer for block bitmap - " > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > index af815ea..afb1bb2 100644 > --- a/fs/ext4/ext4.h > +++ b/fs/ext4/ext4.h > @@ -2531,6 +2531,8 @@ static inline void ext4_unlock_group(struct super_block *sb, > spin_unlock(ext4_group_lock_ptr(sb, group)); > } > > +int ext4_is_sane_bgdata_location(struct super_block *sb, ext4_group_t grp, > + ext4_fsblk_t blk); > /* > * Block validity checking > */ > diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c > index 137193f..242250d 100644 > --- a/fs/ext4/ialloc.c > +++ b/fs/ext4/ialloc.c > @@ -122,6 +122,10 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) > return NULL; > > bitmap_blk = ext4_inode_bitmap(sb, desc); > + if (!ext4_is_sane_bgdata_location(sb, block_group, bitmap_blk)) { > + grp = ext4_get_group_info(sb, block_group); > + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); > + } > bh = sb_getblk(sb, bitmap_blk); > if (unlikely(!bh)) { > ext4_error(sb, "Cannot read inode bitmap - " > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 0d424d7..c5af22e 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -3795,6 +3795,7 @@ static int __ext4_get_inode_loc(struct inode *inode, > struct super_block *sb = inode->i_sb; > ext4_fsblk_t block; > int inodes_per_block, inode_offset; > + struct ext4_group_info *grp; > > iloc->bh = NULL; > if (!ext4_valid_inum(sb, inode->i_ino)) > @@ -3814,6 +3815,11 @@ static int __ext4_get_inode_loc(struct inode *inode, > block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); > iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); > > + if (!ext4_is_sane_bgdata_location(sb, iloc->block_group, block)) { > + grp = ext4_get_group_info(sb, iloc->block_group); > + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); > + return -EIO; > + } > bh = sb_getblk(sb, block); > if (unlikely(!bh)) > return -ENOMEM; > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 2c2e6cb..d22248e 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -2049,6 +2049,27 @@ void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group, > gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp); > } > > +/* returns 1 if the location of a blockgroup data item seems sane */ > +int ext4_is_sane_bgdata_location(struct super_block *sb, ext4_group_t grp, > + ext4_fsblk_t blk) > +{ > + struct ext4_sb_info *sbi = EXT4_SB(sb); > + ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); > + ext4_fsblk_t last_block; > + > + if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) > + last_block = ext4_blocks_count(sbi->s_es) - 1; > + else { > + first_block += grp * sbi->s_blocks_per_group; > + last_block = first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1); > + } > + > + if (last_block >= ext4_blocks_count(sbi->s_es)) > + last_block = ext4_blocks_count(sbi->s_es) - 1; > + > + return blk >= first_block && blk <= last_block; > +} > + > /* Called at mount-time, super-block is locked */ > static int ext4_check_descriptors(struct super_block *sb, > ext4_group_t *first_not_zeroed) > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Sep 27, 2013 at 01:40:55PM +0800, Zheng Liu wrote: > On Thu, Sep 26, 2013 at 05:03:34PM -0700, Darrick J. Wong wrote: > > Perform a quick sanity check of bitmap and inode table block numbers when > > loading them, and if there's something suspicious, mark the block group > > corrupt. > > > > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> > > --- > > fs/ext4/balloc.c | 5 +++++ > > fs/ext4/ext4.h | 2 ++ > > fs/ext4/ialloc.c | 4 ++++ > > fs/ext4/inode.c | 6 ++++++ > > fs/ext4/super.c | 21 +++++++++++++++++++++ > > 5 files changed, 38 insertions(+) > > > > > > diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c > > index 4390f9f..3d79bfe 100644 > > --- a/fs/ext4/balloc.c > > +++ b/fs/ext4/balloc.c > > @@ -396,11 +396,16 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) > > struct ext4_group_desc *desc; > > struct buffer_head *bh; > > ext4_fsblk_t bitmap_blk; > > + struct ext4_group_info *grp; > > > > desc = ext4_get_group_desc(sb, block_group, NULL); > > if (!desc) > > return NULL; > > bitmap_blk = ext4_block_bitmap(sb, desc); > > + if (!ext4_is_sane_bgdata_location(sb, block_group, bitmap_blk)) { > > + grp = ext4_get_group_info(sb, block_group); > > + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); > > Why don't return NULL directly? If we found that the location of bitmap > is insane, we shouldn't read this bitmap. > > - Zheng > > > + } > > bh = sb_getblk(sb, bitmap_blk); > > if (unlikely(!bh)) { > > ext4_error(sb, "Cannot get buffer for block bitmap - " I thought it was fine in the event of an insane blockno to fall through to this error message. I could make that more explicit, though. --D > > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > > index af815ea..afb1bb2 100644 > > --- a/fs/ext4/ext4.h > > +++ b/fs/ext4/ext4.h > > @@ -2531,6 +2531,8 @@ static inline void ext4_unlock_group(struct super_block *sb, > > spin_unlock(ext4_group_lock_ptr(sb, group)); > > } > > > > +int ext4_is_sane_bgdata_location(struct super_block *sb, ext4_group_t grp, > > + ext4_fsblk_t blk); > > /* > > * Block validity checking > > */ > > diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c > > index 137193f..242250d 100644 > > --- a/fs/ext4/ialloc.c > > +++ b/fs/ext4/ialloc.c > > @@ -122,6 +122,10 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) > > return NULL; > > > > bitmap_blk = ext4_inode_bitmap(sb, desc); > > + if (!ext4_is_sane_bgdata_location(sb, block_group, bitmap_blk)) { > > + grp = ext4_get_group_info(sb, block_group); > > + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); > > + } > > bh = sb_getblk(sb, bitmap_blk); > > if (unlikely(!bh)) { > > ext4_error(sb, "Cannot read inode bitmap - " > > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > > index 0d424d7..c5af22e 100644 > > --- a/fs/ext4/inode.c > > +++ b/fs/ext4/inode.c > > @@ -3795,6 +3795,7 @@ static int __ext4_get_inode_loc(struct inode *inode, > > struct super_block *sb = inode->i_sb; > > ext4_fsblk_t block; > > int inodes_per_block, inode_offset; > > + struct ext4_group_info *grp; > > > > iloc->bh = NULL; > > if (!ext4_valid_inum(sb, inode->i_ino)) > > @@ -3814,6 +3815,11 @@ static int __ext4_get_inode_loc(struct inode *inode, > > block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); > > iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); > > > > + if (!ext4_is_sane_bgdata_location(sb, iloc->block_group, block)) { > > + grp = ext4_get_group_info(sb, iloc->block_group); > > + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); > > + return -EIO; > > + } > > bh = sb_getblk(sb, block); > > if (unlikely(!bh)) > > return -ENOMEM; > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > > index 2c2e6cb..d22248e 100644 > > --- a/fs/ext4/super.c > > +++ b/fs/ext4/super.c > > @@ -2049,6 +2049,27 @@ void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group, > > gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp); > > } > > > > +/* returns 1 if the location of a blockgroup data item seems sane */ > > +int ext4_is_sane_bgdata_location(struct super_block *sb, ext4_group_t grp, > > + ext4_fsblk_t blk) > > +{ > > + struct ext4_sb_info *sbi = EXT4_SB(sb); > > + ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); > > + ext4_fsblk_t last_block; > > + > > + if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) > > + last_block = ext4_blocks_count(sbi->s_es) - 1; > > + else { > > + first_block += grp * sbi->s_blocks_per_group; > > + last_block = first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1); > > + } > > + > > + if (last_block >= ext4_blocks_count(sbi->s_es)) > > + last_block = ext4_blocks_count(sbi->s_es) - 1; > > + > > + return blk >= first_block && blk <= last_block; > > +} > > + > > /* Called at mount-time, super-block is locked */ > > static int ext4_check_descriptors(struct super_block *sb, > > ext4_group_t *first_not_zeroed) > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 4390f9f..3d79bfe 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -396,11 +396,16 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) struct ext4_group_desc *desc; struct buffer_head *bh; ext4_fsblk_t bitmap_blk; + struct ext4_group_info *grp; desc = ext4_get_group_desc(sb, block_group, NULL); if (!desc) return NULL; bitmap_blk = ext4_block_bitmap(sb, desc); + if (!ext4_is_sane_bgdata_location(sb, block_group, bitmap_blk)) { + grp = ext4_get_group_info(sb, block_group); + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); + } bh = sb_getblk(sb, bitmap_blk); if (unlikely(!bh)) { ext4_error(sb, "Cannot get buffer for block bitmap - " diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index af815ea..afb1bb2 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2531,6 +2531,8 @@ static inline void ext4_unlock_group(struct super_block *sb, spin_unlock(ext4_group_lock_ptr(sb, group)); } +int ext4_is_sane_bgdata_location(struct super_block *sb, ext4_group_t grp, + ext4_fsblk_t blk); /* * Block validity checking */ diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 137193f..242250d 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -122,6 +122,10 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) return NULL; bitmap_blk = ext4_inode_bitmap(sb, desc); + if (!ext4_is_sane_bgdata_location(sb, block_group, bitmap_blk)) { + grp = ext4_get_group_info(sb, block_group); + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); + } bh = sb_getblk(sb, bitmap_blk); if (unlikely(!bh)) { ext4_error(sb, "Cannot read inode bitmap - " diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 0d424d7..c5af22e 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3795,6 +3795,7 @@ static int __ext4_get_inode_loc(struct inode *inode, struct super_block *sb = inode->i_sb; ext4_fsblk_t block; int inodes_per_block, inode_offset; + struct ext4_group_info *grp; iloc->bh = NULL; if (!ext4_valid_inum(sb, inode->i_ino)) @@ -3814,6 +3815,11 @@ static int __ext4_get_inode_loc(struct inode *inode, block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block); iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); + if (!ext4_is_sane_bgdata_location(sb, iloc->block_group, block)) { + grp = ext4_get_group_info(sb, iloc->block_group); + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); + return -EIO; + } bh = sb_getblk(sb, block); if (unlikely(!bh)) return -ENOMEM; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 2c2e6cb..d22248e 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2049,6 +2049,27 @@ void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group, gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp); } +/* returns 1 if the location of a blockgroup data item seems sane */ +int ext4_is_sane_bgdata_location(struct super_block *sb, ext4_group_t grp, + ext4_fsblk_t blk) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block); + ext4_fsblk_t last_block; + + if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) + last_block = ext4_blocks_count(sbi->s_es) - 1; + else { + first_block += grp * sbi->s_blocks_per_group; + last_block = first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1); + } + + if (last_block >= ext4_blocks_count(sbi->s_es)) + last_block = ext4_blocks_count(sbi->s_es) - 1; + + return blk >= first_block && blk <= last_block; +} + /* Called at mount-time, super-block is locked */ static int ext4_check_descriptors(struct super_block *sb, ext4_group_t *first_not_zeroed)
Perform a quick sanity check of bitmap and inode table block numbers when loading them, and if there's something suspicious, mark the block group corrupt. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> --- fs/ext4/balloc.c | 5 +++++ fs/ext4/ext4.h | 2 ++ fs/ext4/ialloc.c | 4 ++++ fs/ext4/inode.c | 6 ++++++ fs/ext4/super.c | 21 +++++++++++++++++++++ 5 files changed, 38 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html