From: "zhangyi (F)" yi.zhang@huawei.com
mainline inclusion from mainline-5.10-rc1 commit 5df1d4123d53261d9d71c7d237d0f165add7ce72 category: bugfix bugzilla: 51832 CVE: NA ---------------------------
If we readahead inode tables in __ext4_get_inode_loc(), it may bypass buffer_write_io_error() check, so introduce ext4_sb_breadahead_unmovable() to handle this special case.
This patch also replace sb_breadahead_unmovable() in ext4_fill_super() for the sake of unification.
Signed-off-by: zhangyi (F) yi.zhang@huawei.com Link: https://lore.kernel.org/r/20200924073337.861472-6-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: yangerkun yangerkun@huawei.com Reviewed-by: zhangyi (F) yi.zhang@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- fs/ext4/ext4.h | 1 + fs/ext4/inode.c | 2 +- fs/ext4/super.c | 12 +++++++++++- 3 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 1ea777a66c8cb..03c660459d311 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2727,6 +2727,7 @@ extern void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags, extern int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io); extern int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait); +extern void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block); extern int ext4_seq_options_show(struct seq_file *seq, void *offset); extern int ext4_calculate_overhead(struct super_block *sb); extern void ext4_superblock_csum_set(struct super_block *sb); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b27dcd80caf06..1761ba640a26d 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4707,7 +4707,7 @@ static int __ext4_get_inode_loc(struct inode *inode, if (end > table) end = table; while (b <= end) - sb_breadahead_unmovable(sb, b++); + ext4_sb_breadahead_unmovable(sb, b++); }
/* diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 24dc9137185ff..ec9df6f427688 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -236,6 +236,16 @@ ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags) return bh; }
+void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block) +{ + struct buffer_head *bh = sb_getblk_gfp(sb, block, 0); + + if (likely(bh)) { + ext4_read_bh_lock(bh, REQ_RAHEAD, false); + brelse(bh); + } +} + static int ext4_verify_csum_type(struct super_block *sb, struct ext4_super_block *es) { @@ -4374,7 +4384,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) /* Pre-read the descriptors into the buffer cache */ for (i = 0; i < db_count; i++) { block = descriptor_loc(sb, logical_sb_block, i); - sb_breadahead_unmovable(sb, block); + ext4_sb_breadahead_unmovable(sb, block); }
for (i = 0; i < db_count; i++) {