From b0dd6b70f0fda17ae9762fbb72d98e40a4f66556 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Thu, 7 Jun 2012 18:56:06 -0400 Subject: ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg Ext3 filesystems that are converted to use as many ext4 file system features as possible will enable uninit_bg to speed up e2fsck times. These file systems will have a native ext3 layout of inode tables and block allocation bitmaps (as opposed to ext4's flex_bg layout). Unfortunately, in these cases, when first allocating a block in an uninitialized block group, ext4 would incorrectly calculate the number of free blocks in that block group, and then errorneously report that the file system was corrupt: EXT4-fs error (device vdd): ext4_mb_generate_buddy:741: group 30, 32254 clusters in bitmap, 32258 in gd This problem can be reproduced via: mke2fs -q -t ext4 -O ^flex_bg /dev/vdd 5g mount -t ext4 /dev/vdd /mnt fallocate -l 4600m /mnt/test The problem was caused by a bone headed mistake in the check to see if a particular metadata block was part of the block group. Many thanks to Kees Cook for finding and bisecting the buggy commit which introduced this bug (commit fd034a84e1, present since v3.2). Reported-by: Sander Eikelenboom Reported-by: Kees Cook Signed-off-by: "Theodore Ts'o" Tested-by: Kees Cook Cc: stable@kernel.org --- fs/ext4/balloc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 99b6324290d..cee7812cc3c 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -90,8 +90,8 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb, * unusual file system layouts. */ if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) { - block_cluster = EXT4_B2C(sbi, (start - - ext4_block_bitmap(sb, gdp))); + block_cluster = EXT4_B2C(sbi, + ext4_block_bitmap(sb, gdp) - start); if (block_cluster < num_clusters) block_cluster = -1; else if (block_cluster == num_clusters) { @@ -102,7 +102,7 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb, if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) { inode_cluster = EXT4_B2C(sbi, - start - ext4_inode_bitmap(sb, gdp)); + ext4_inode_bitmap(sb, gdp) - start); if (inode_cluster < num_clusters) inode_cluster = -1; else if (inode_cluster == num_clusters) { @@ -114,7 +114,7 @@ unsigned ext4_num_overhead_clusters(struct super_block *sb, itbl_blk = ext4_inode_table(sb, gdp); for (i = 0; i < sbi->s_itb_per_group; i++) { if (ext4_block_in_group(sb, itbl_blk + i, block_group)) { - c = EXT4_B2C(sbi, start - itbl_blk + i); + c = EXT4_B2C(sbi, itbl_blk + i - start); if ((c < num_clusters) || (c == inode_cluster) || (c == block_cluster) || (c == itbl_cluster)) continue; -- cgit v1.2.3-70-g09d2 From b22b1f178f6799278d3178d894f37facb2085765 Mon Sep 17 00:00:00 2001 From: Tao Ma Date: Thu, 7 Jun 2012 19:04:19 -0400 Subject: ext4: don't set i_flags in EXT4_IOC_SETFLAGS Commit 7990696 uses the ext4_{set,clear}_inode_flags() functions to change the i_flags automatically but fails to remove the error setting of i_flags. So we still have the problem of trashing state flags. Fix this by removing the assignment. Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org --- fs/ext4/ioctl.c | 1 - 1 file changed, 1 deletion(-) diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 8ad112ae0ad..e34deac3f36 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -123,7 +123,6 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) else ext4_clear_inode_flag(inode, i); } - ei->i_flags = flags; ext4_set_inode_flags(inode); inode->i_ctime = ext4_current_time(inode); -- cgit v1.2.3-70-g09d2