| From 819b23f1c501b17b9694325471789e6b5cc2d0d2 Mon Sep 17 00:00:00 2001 |
| From: Theodore Ts'o <tytso@mit.edu> |
| Date: Wed, 13 Jun 2018 23:00:48 -0400 |
| Subject: ext4: always check block group bounds in ext4_init_block_bitmap() |
| |
| From: Theodore Ts'o <tytso@mit.edu> |
| |
| commit 819b23f1c501b17b9694325471789e6b5cc2d0d2 upstream. |
| |
| 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 <tytso@mit.edu> |
| Cc: stable@kernel.org |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| fs/ext4/balloc.c | 10 +++------- |
| 1 file changed, 3 insertions(+), 7 deletions(-) |
| |
| --- a/fs/ext4/balloc.c |
| +++ b/fs/ext4/balloc.c |
| @@ -183,7 +183,6 @@ static int ext4_init_block_bitmap(struct |
| unsigned int bit, bit_max; |
| struct ext4_sb_info *sbi = EXT4_SB(sb); |
| ext4_fsblk_t start, tmp; |
| - int flex_bg = 0; |
| struct ext4_group_info *grp; |
| |
| J_ASSERT_BH(bh, buffer_locked(bh)); |
| @@ -216,22 +215,19 @@ static int ext4_init_block_bitmap(struct |
| |
| 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); |
| } |
| |