From 819b23f1c501b17b9694325471789e6b5cc2d0d2 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Wed, 13 Jun 2018 23:00:48 -0400 Subject: [PATCH] ext4: always check block group bounds in ext4_init_block_bitmap() Regardless of whether the flex_bg feature is set, we should always check to make sure the bits we are setting in the block bitmap are within the block group bounds. https://bugzilla.kernel.org/show_bug.cgi?id=199865 Signed-off-by: Theodore Ts'o Cc: stable@kernel.org --- fs/ext4/balloc.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index b00481c475cb..8a2e202ade8a 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -184,7 +184,6 @@ static int ext4_init_block_bitmap(struct super_block *sb, unsigned int bit, bit_max; struct ext4_sb_info *sbi = EXT4_SB(sb); ext4_fsblk_t start, tmp; - int flex_bg = 0; J_ASSERT_BH(bh, buffer_locked(bh)); @@ -207,22 +206,19 @@ static int ext4_init_block_bitmap(struct super_block *sb, start = ext4_group_first_block_no(sb, block_group); - if (ext4_has_feature_flex_bg(sb)) - flex_bg = 1; - /* Set bits for block and inode bitmaps, and inode table */ tmp = ext4_block_bitmap(sb, gdp); - if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) + if (ext4_block_in_group(sb, tmp, block_group)) ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); tmp = ext4_inode_bitmap(sb, gdp); - if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) + if (ext4_block_in_group(sb, tmp, block_group)) ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); tmp = ext4_inode_table(sb, gdp); for (; tmp < ext4_inode_table(sb, gdp) + sbi->s_itb_per_group; tmp++) { - if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) + if (ext4_block_in_group(sb, tmp, block_group)) ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); } -- 2.30.2