diff mbox series

[v3,1/3] ext4: fix incorrect calculate 'reserved' in '__es_remove_extent' when enable bigalloc feature

Message ID 20221203025941.2661302-2-yebin@huaweicloud.com
State Superseded
Headers show
Series Fix two issues about bigalloc feature | expand

Commit Message

Ye Bin Dec. 3, 2022, 2:59 a.m. UTC 
From: Ye Bin <yebin10@huawei.com>

Syzbot report issue as follows:
EXT4-fs error (device loop0): ext4_validate_block_bitmap:398: comm rep: bg 0: block 5: invalid block bitmap
EXT4-fs (loop0): Delayed block allocation failed for inode 18 at logical offset 0 with max blocks 32 with error 28
EXT4-fs (loop0): This should not happen!! Data will be lost

EXT4-fs (loop0): Total free blocks count 0
EXT4-fs (loop0): Free/Dirty block details
EXT4-fs (loop0): free_blocks=0
EXT4-fs (loop0): dirty_blocks=32
EXT4-fs (loop0): Block reservation details
EXT4-fs (loop0): i_reserved_data_blocks=2
EXT4-fs (loop0): Inode 18 (00000000845cd634): i_reserved_data_blocks (1) not cleared!

Above issue happens as follows:
Assume:
sbi->s_cluster_ratio = 16
Step1: Insert delay block [0, 31] -> ei->i_reserved_data_blocks=2
Step2:
ext4_writepages
  mpage_map_and_submit_extent -> return failed
  mpage_release_unused_pages -> to release [0, 30]
    ext4_es_remove_extent -> remove lblk=0 end=30
      __es_remove_extent -> len1=0 len2=31-30=1
 __es_remove_extent:
 ...
 if (len2 > 0) {
  ...
	  if (len1 > 0) {
		  ...
	  } else {
		es->es_lblk = end + 1;
		es->es_len = len2;
		...
	  }
  	if (count_reserved)
		count_rsvd(inode, lblk, orig_es.es_len - len1 - len2, &orig_es, &rc);
	goto out; -> will return but didn't calculate 'reserved'
 ...
Step3: ext4_destroy_inode -> trigger "i_reserved_data_blocks (1) not cleared!"

To solve above issue if 'len2>0' call 'get_rsvd()' before goto out.

Reported-by: syzbot+05a0f0ccab4a25626e38@syzkaller.appspotmail.com
Fixes: 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages")
Signed-off-by: Ye Bin <yebin10@huawei.com>
---
 fs/ext4/extents_status.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Eric Whitney Dec. 7, 2022, 11:01 p.m. UTC | #1 
* Ye Bin <yebin@huaweicloud.com>:
> From: Ye Bin <yebin10@huawei.com>
> 
> Syzbot report issue as follows:
> EXT4-fs error (device loop0): ext4_validate_block_bitmap:398: comm rep: bg 0: block 5: invalid block bitmap
> EXT4-fs (loop0): Delayed block allocation failed for inode 18 at logical offset 0 with max blocks 32 with error 28
> EXT4-fs (loop0): This should not happen!! Data will be lost
> 
> EXT4-fs (loop0): Total free blocks count 0
> EXT4-fs (loop0): Free/Dirty block details
> EXT4-fs (loop0): free_blocks=0
> EXT4-fs (loop0): dirty_blocks=32
> EXT4-fs (loop0): Block reservation details
> EXT4-fs (loop0): i_reserved_data_blocks=2
> EXT4-fs (loop0): Inode 18 (00000000845cd634): i_reserved_data_blocks (1) not cleared!
> 
> Above issue happens as follows:
> Assume:
> sbi->s_cluster_ratio = 16
> Step1: Insert delay block [0, 31] -> ei->i_reserved_data_blocks=2
> Step2:
> ext4_writepages
>   mpage_map_and_submit_extent -> return failed
>   mpage_release_unused_pages -> to release [0, 30]
>     ext4_es_remove_extent -> remove lblk=0 end=30
>       __es_remove_extent -> len1=0 len2=31-30=1
>  __es_remove_extent:
>  ...
>  if (len2 > 0) {
>   ...
> 	  if (len1 > 0) {
> 		  ...
> 	  } else {
> 		es->es_lblk = end + 1;
> 		es->es_len = len2;
> 		...
> 	  }
>   	if (count_reserved)
> 		count_rsvd(inode, lblk, orig_es.es_len - len1 - len2, &orig_es, &rc);
> 	goto out; -> will return but didn't calculate 'reserved'
>  ...
> Step3: ext4_destroy_inode -> trigger "i_reserved_data_blocks (1) not cleared!"
> 
> To solve above issue if 'len2>0' call 'get_rsvd()' before goto out.
> 
> Reported-by: syzbot+05a0f0ccab4a25626e38@syzkaller.appspotmail.com
> Fixes: 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages")
> Signed-off-by: Ye Bin <yebin10@huawei.com>
> ---
>  fs/ext4/extents_status.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
> index cd0a861853e3..7ada374ff27d 100644
> --- a/fs/ext4/extents_status.c
> +++ b/fs/ext4/extents_status.c
> @@ -1371,7 +1371,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
>  		if (count_reserved)
>  			count_rsvd(inode, lblk, orig_es.es_len - len1 - len2,
>  				   &orig_es, &rc);
> -		goto out;
> +		goto out_get_reserved;
>  	}
>  
>  	if (len1 > 0) {
> @@ -1413,6 +1413,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
>  		}
>  	}
>  
> +out_get_reserved:
>  	if (count_reserved)
>  		*reserved = get_rsvd(inode, end, es, &rc);
>  out:

The length of some lines in the commit description - probably those which are
log output - is resulting in a checkpatch warning.  It generally prefers lines
to be a maximum of 75 characters (and Ted usually likes them limited to 72
characters.  See my comment to patch #3. I'm not sure what Ted would want here,
though I'd probably break them at 72 characters or less.

Otherwise, the patch looks good.  Feel free to add:

Reviewed-by: Eric Whitney <enwlinux@gmail.com>

> -- 
> 2.31.1
>
Eric Whitney Dec. 8, 2022, 10:53 p.m. UTC | #2 
* Eric Whitney <enwlinux@gmail.com>:
> * Ye Bin <yebin@huaweicloud.com>:
> > From: Ye Bin <yebin10@huawei.com>
> > 
> > Syzbot report issue as follows:
> > EXT4-fs error (device loop0): ext4_validate_block_bitmap:398: comm rep: bg 0: block 5: invalid block bitmap
> > EXT4-fs (loop0): Delayed block allocation failed for inode 18 at logical offset 0 with max blocks 32 with error 28
> > EXT4-fs (loop0): This should not happen!! Data will be lost
> > 
> > EXT4-fs (loop0): Total free blocks count 0
> > EXT4-fs (loop0): Free/Dirty block details
> > EXT4-fs (loop0): free_blocks=0
> > EXT4-fs (loop0): dirty_blocks=32
> > EXT4-fs (loop0): Block reservation details
> > EXT4-fs (loop0): i_reserved_data_blocks=2
> > EXT4-fs (loop0): Inode 18 (00000000845cd634): i_reserved_data_blocks (1) not cleared!
> > 
> > Above issue happens as follows:
> > Assume:
> > sbi->s_cluster_ratio = 16
> > Step1: Insert delay block [0, 31] -> ei->i_reserved_data_blocks=2
> > Step2:
> > ext4_writepages
> >   mpage_map_and_submit_extent -> return failed
> >   mpage_release_unused_pages -> to release [0, 30]
> >     ext4_es_remove_extent -> remove lblk=0 end=30
> >       __es_remove_extent -> len1=0 len2=31-30=1
> >  __es_remove_extent:
> >  ...
> >  if (len2 > 0) {
> >   ...
> > 	  if (len1 > 0) {
> > 		  ...
> > 	  } else {
> > 		es->es_lblk = end + 1;
> > 		es->es_len = len2;
> > 		...
> > 	  }
> >   	if (count_reserved)
> > 		count_rsvd(inode, lblk, orig_es.es_len - len1 - len2, &orig_es, &rc);
> > 	goto out; -> will return but didn't calculate 'reserved'
> >  ...
> > Step3: ext4_destroy_inode -> trigger "i_reserved_data_blocks (1) not cleared!"
> > 
> > To solve above issue if 'len2>0' call 'get_rsvd()' before goto out.
> > 
> > Reported-by: syzbot+05a0f0ccab4a25626e38@syzkaller.appspotmail.com
> > Fixes: 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages")
> > Signed-off-by: Ye Bin <yebin10@huawei.com>
> > ---
> >  fs/ext4/extents_status.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
> > index cd0a861853e3..7ada374ff27d 100644
> > --- a/fs/ext4/extents_status.c
> > +++ b/fs/ext4/extents_status.c
> > @@ -1371,7 +1371,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
> >  		if (count_reserved)
> >  			count_rsvd(inode, lblk, orig_es.es_len - len1 - len2,
> >  				   &orig_es, &rc);
> > -		goto out;
> > +		goto out_get_reserved;
> >  	}
> >  
> >  	if (len1 > 0) {
> > @@ -1413,6 +1413,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
> >  		}
> >  	}
> >  
> > +out_get_reserved:
> >  	if (count_reserved)
> >  		*reserved = get_rsvd(inode, end, es, &rc);
> >  out:
> 
> The length of some lines in the commit description - probably those which are
> log output - is resulting in a checkpatch warning.  It generally prefers lines
> to be a maximum of 75 characters (and Ted usually likes them limited to 72
> characters.  See my comment to patch #3. I'm not sure what Ted would want here,
> though I'd probably break them at 72 characters or less.
> 
> Otherwise, the patch looks good.  Feel free to add:
> 

Looks good.  As before, feel free to add:

> Reviewed-by: Eric Whitney <enwlinux@gmail.com>

> 
> > -- 
> > 2.31.1
> >
Eric Whitney Dec. 8, 2022, 10:54 p.m. UTC | #3 
* Eric Whitney <enwlinux@gmail.com>:
> * Eric Whitney <enwlinux@gmail.com>:
> > * Ye Bin <yebin@huaweicloud.com>:
> > > From: Ye Bin <yebin10@huawei.com>
> > > 
> > > Syzbot report issue as follows:
> > > EXT4-fs error (device loop0): ext4_validate_block_bitmap:398: comm rep: bg 0: block 5: invalid block bitmap
> > > EXT4-fs (loop0): Delayed block allocation failed for inode 18 at logical offset 0 with max blocks 32 with error 28
> > > EXT4-fs (loop0): This should not happen!! Data will be lost
> > > 
> > > EXT4-fs (loop0): Total free blocks count 0
> > > EXT4-fs (loop0): Free/Dirty block details
> > > EXT4-fs (loop0): free_blocks=0
> > > EXT4-fs (loop0): dirty_blocks=32
> > > EXT4-fs (loop0): Block reservation details
> > > EXT4-fs (loop0): i_reserved_data_blocks=2
> > > EXT4-fs (loop0): Inode 18 (00000000845cd634): i_reserved_data_blocks (1) not cleared!
> > > 
> > > Above issue happens as follows:
> > > Assume:
> > > sbi->s_cluster_ratio = 16
> > > Step1: Insert delay block [0, 31] -> ei->i_reserved_data_blocks=2
> > > Step2:
> > > ext4_writepages
> > >   mpage_map_and_submit_extent -> return failed
> > >   mpage_release_unused_pages -> to release [0, 30]
> > >     ext4_es_remove_extent -> remove lblk=0 end=30
> > >       __es_remove_extent -> len1=0 len2=31-30=1
> > >  __es_remove_extent:
> > >  ...
> > >  if (len2 > 0) {
> > >   ...
> > > 	  if (len1 > 0) {
> > > 		  ...
> > > 	  } else {
> > > 		es->es_lblk = end + 1;
> > > 		es->es_len = len2;
> > > 		...
> > > 	  }
> > >   	if (count_reserved)
> > > 		count_rsvd(inode, lblk, orig_es.es_len - len1 - len2, &orig_es, &rc);
> > > 	goto out; -> will return but didn't calculate 'reserved'
> > >  ...
> > > Step3: ext4_destroy_inode -> trigger "i_reserved_data_blocks (1) not cleared!"
> > > 
> > > To solve above issue if 'len2>0' call 'get_rsvd()' before goto out.
> > > 
> > > Reported-by: syzbot+05a0f0ccab4a25626e38@syzkaller.appspotmail.com
> > > Fixes: 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages")
> > > Signed-off-by: Ye Bin <yebin10@huawei.com>
> > > ---
> > >  fs/ext4/extents_status.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
> > > index cd0a861853e3..7ada374ff27d 100644
> > > --- a/fs/ext4/extents_status.c
> > > +++ b/fs/ext4/extents_status.c
> > > @@ -1371,7 +1371,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
> > >  		if (count_reserved)
> > >  			count_rsvd(inode, lblk, orig_es.es_len - len1 - len2,
> > >  				   &orig_es, &rc);
> > > -		goto out;
> > > +		goto out_get_reserved;
> > >  	}
> > >  
> > >  	if (len1 > 0) {
> > > @@ -1413,6 +1413,7 @@ static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
> > >  		}
> > >  	}
> > >  
> > > +out_get_reserved:
> > >  	if (count_reserved)
> > >  		*reserved = get_rsvd(inode, end, es, &rc);
> > >  out:
> > 
> > The length of some lines in the commit description - probably those which are
> > log output - is resulting in a checkpatch warning.  It generally prefers lines
> > to be a maximum of 75 characters (and Ted usually likes them limited to 72
> > characters.  See my comment to patch #3. I'm not sure what Ted would want here,
> > though I'd probably break them at 72 characters or less.
> > 
> > Otherwise, the patch looks good.  Feel free to add:
> > 
> 
> Looks good.  As before, feel free to add:
> 
> > Reviewed-by: Eric Whitney <enwlinux@gmail.com>
> 

Whoops.  Please disregard - wrong patch.

Eric
diff mbox series

Patch

diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index cd0a861853e3..7ada374ff27d 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -1371,7 +1371,7 @@  static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
 		if (count_reserved)
 			count_rsvd(inode, lblk, orig_es.es_len - len1 - len2,
 				   &orig_es, &rc);
-		goto out;
+		goto out_get_reserved;
 	}
 
 	if (len1 > 0) {
@@ -1413,6 +1413,7 @@  static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
 		}
 	}
 
+out_get_reserved:
 	if (count_reserved)
 		*reserved = get_rsvd(inode, end, es, &rc);
 out: