2022-01-13 07:46:41

by Ritesh Harjani

Subject: [PATCH 1/6] ext4: Fix error handling in ext4_restore_inline_data()

While running "./check -I 200 generic/475" it sometimes gives below
kernel BUG(). Ideally we should not call ext4_write_inline_data() if
ext4_create_inline_data() has failed.

<log snip>
[73131.453234] kernel BUG at fs/ext4/inline.c:223!

<code snip>
212 static void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
213 void *buffer, loff_t pos, unsigned int len)
214 {
<...>
223 BUG_ON(!EXT4_I(inode)->i_inline_off);
224 BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);

This patch handles the error and prints out a emergency msg saying potential
data loss for the given inode (since we couldn't restore the original
inline_data due to some previous error).

[ 9571.070313] EXT4-fs (dm-0): error restoring inline_data for inode -- potential data loss! (inode 1703982, error -30)

Reported-by: Eric Whitney <[email protected]>
Signed-off-by: Ritesh Harjani <[email protected]>
---
fs/ext4/inline.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index 534c0329e110..31741e8a462e 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -1135,7 +1135,15 @@ static void ext4_restore_inline_data(handle_t *handle, struct inode *inode,
struct ext4_iloc *iloc,
void *buf, int inline_size)
{
- ext4_create_inline_data(handle, inode, inline_size);
+ int ret;
+
+ ret = ext4_create_inline_data(handle, inode, inline_size);
+ if (ret) {
+ ext4_msg(inode->i_sb, KERN_EMERG,
+ "error restoring inline_data for inode -- potential data loss! (inode %lu, error %d)",
+ inode->i_ino, ret);
+ return;
+ }
ext4_write_inline_data(inode, iloc, buf, 0, inline_size);
ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
}
--
2.31.1

2022-01-13 17:04:26

by Jan Kara

Subject: Re: [PATCH 1/6] ext4: Fix error handling in ext4_restore_inline_data()

On Thu 13-01-22 08:56:24, Ritesh Harjani wrote:
> While running "./check -I 200 generic/475" it sometimes gives below
> kernel BUG(). Ideally we should not call ext4_write_inline_data() if
> ext4_create_inline_data() has failed.
>
> <log snip>
> [73131.453234] kernel BUG at fs/ext4/inline.c:223!
>
> <code snip>
> 212 static void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
> 213 void *buffer, loff_t pos, unsigned int len)
> 214 {
> <...>
> 223 BUG_ON(!EXT4_I(inode)->i_inline_off);
> 224 BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
>
> This patch handles the error and prints out a emergency msg saying potential
> data loss for the given inode (since we couldn't restore the original
> inline_data due to some previous error).
>
> [ 9571.070313] EXT4-fs (dm-0): error restoring inline_data for inode -- potential data loss! (inode 1703982, error -30)
>
> Reported-by: Eric Whitney <[email protected]>
> Signed-off-by: Ritesh Harjani <[email protected]>

Makes sence. Feel free to add:

Reviewed-by: Jan Kara <[email protected]>

Honza

> ---
> fs/ext4/inline.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
> index 534c0329e110..31741e8a462e 100644
> --- a/fs/ext4/inline.c
> +++ b/fs/ext4/inline.c
> @@ -1135,7 +1135,15 @@ static void ext4_restore_inline_data(handle_t *handle, struct inode *inode,
> struct ext4_iloc *iloc,
> void *buf, int inline_size)
> {
> - ext4_create_inline_data(handle, inode, inline_size);
> + int ret;
> +
> + ret = ext4_create_inline_data(handle, inode, inline_size);
> + if (ret) {
> + ext4_msg(inode->i_sb, KERN_EMERG,
> + "error restoring inline_data for inode -- potential data loss! (inode %lu, error %d)",
> + inode->i_ino, ret);
> + return;
> + }
> ext4_write_inline_data(inode, iloc, buf, 0, inline_size);
> ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
> }
> --
> 2.31.1
>
--
Jan Kara <[email protected]>
SUSE Labs, CR