2023-04-17 03:05:27

by Kemeng Shi

Subject: [PATCH v3 08/19] ext4: get block from bh before pass it to ext4_free_blocks_simple in ext4_free_blocks

ext4_free_blocks will retrieve block from bh if block parameter is zero.
Retrieve block before ext4_free_blocks_simple to avoid potentially
passing wrong block to ext4_free_blocks_simple.

Signed-off-by: Kemeng Shi <[email protected]>
---
fs/ext4/mballoc.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index e980513c7a14..f37e921c11e5 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -6310,12 +6310,6 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,

sbi = EXT4_SB(sb);

- if (sbi->s_mount_state & EXT4_FC_REPLAY) {
- ext4_free_blocks_simple(inode, block, count);
- return;
- }
-
- might_sleep();
if (bh) {
if (block)
BUG_ON(block != bh->b_blocknr);
@@ -6323,6 +6317,13 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
block = bh->b_blocknr;
}

+ if (sbi->s_mount_state & EXT4_FC_REPLAY) {
+ ext4_free_blocks_simple(inode, block, count);
+ return;
+ }
+
+ might_sleep();
+
if (!(flags & EXT4_FREE_BLOCKS_VALIDATED) &&
!ext4_inode_block_valid(inode, block, count)) {
ext4_error(sb, "Freeing blocks not in datazone - "
--
2.30.0

2023-05-12 06:32:05

by Ojaswin Mujoo

Subject: Re: [PATCH v3 08/19] ext4: get block from bh before pass it to ext4_free_blocks_simple in ext4_free_blocks

On Mon, Apr 17, 2023 at 07:06:06PM +0800, Kemeng Shi wrote:
> ext4_free_blocks will retrieve block from bh if block parameter is zero.
> Retrieve block before ext4_free_blocks_simple to avoid potentially
> passing wrong block to ext4_free_blocks_simple.
>
> Signed-off-by: Kemeng Shi <[email protected]>
Hi Kemeng,

Nice catch! feel free to add:

Reviewed-by: Ojaswin Mujoo <[email protected]>
> ---
> fs/ext4/mballoc.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> index e980513c7a14..f37e921c11e5 100644
> --- a/fs/ext4/mballoc.c
> +++ b/fs/ext4/mballoc.c
> @@ -6310,12 +6310,6 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
>
> sbi = EXT4_SB(sb);
>
> - if (sbi->s_mount_state & EXT4_FC_REPLAY) {
> - ext4_free_blocks_simple(inode, block, count);
> - return;
> - }
> -
> - might_sleep();
> if (bh) {
> if (block)
> BUG_ON(block != bh->b_blocknr);
> @@ -6323,6 +6317,13 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode,
> block = bh->b_blocknr;
> }
>
> + if (sbi->s_mount_state & EXT4_FC_REPLAY) {
> + ext4_free_blocks_simple(inode, block, count);
> + return;
> + }
> +
> + might_sleep();
> +
> if (!(flags & EXT4_FREE_BLOCKS_VALIDATED) &&
> !ext4_inode_block_valid(inode, block, count)) {
> ext4_error(sb, "Freeing blocks not in datazone - "
> --
> 2.30.0
>