diff mbox series

[v3] xfs: add agf freeblocks verify in xfs_agf_verify

Message ID 1582260435-20939-1-git-send-email-zhengbin13@huawei.com (mailing list archive)
State Accepted
Headers show
Series [v3] xfs: add agf freeblocks verify in xfs_agf_verify | expand

Commit Message

Zheng Bin Feb. 21, 2020, 4:47 a.m. UTC 
We recently used fuzz(hydra) to test XFS and automatically generate
tmp.img(XFS v5 format, but some metadata is wrong)

xfs_repair information(just one AG):
agf_freeblks 0, counted 3224 in ag 0
agf_longest 536874136, counted 3224 in ag 0
sb_fdblocks 613, counted 3228

Test as follows:
mount tmp.img tmpdir
cp file1M tmpdir
sync

In 4.19-stable, sync will stuck, the reason is:
xfs_mountfs
  xfs_check_summary_counts
    if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
       XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
       !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
	return 0;  -->just return, incore sb_fdblocks still be 613
    xfs_initialize_perag_data

cp file1M tmpdir -->ok(write file to pagecache)
sync -->stuck(write pagecache to disk)
xfs_map_blocks
  xfs_iomap_write_allocate
    while (count_fsb != 0) {
      nimaps = 0;
      while (nimaps == 0) { --> endless loop
         nimaps = 1;
         xfs_bmapi_write(..., &nimaps) --> nimaps becomes 0 again
xfs_bmapi_write
  xfs_bmap_alloc
    xfs_bmap_btalloc
      xfs_alloc_vextent
        xfs_alloc_fix_freelist
          xfs_alloc_space_available -->fail(agf_freeblks is 0)

In linux-next, sync not stuck, cause commit c2b3164320b5 ("xfs:
use the latest extent at writeback delalloc conversion time") remove
the above while, dmesg is as follows:
[   55.250114] XFS (loop0): page discard on page ffffea0008bc7380, inode 0x1b0c, offset 0.

Users do not know why this page is discard, the better soultion is:
1. Like xfs_repair, make sure sb_fdblocks is equal to counted
(xfs_initialize_perag_data did this, who is not called at this mount)
2. Add agf verify, if fail, will tell users to repair

This patch use the second soultion.

Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: Ren Xudong <renxudong1@huawei.com>
---

v1->v2: modify comment, add more agf verify
v2->v3: modify code which is suggested by hellwig & darrick
besides, remove the agf_freeblks < sb_fdblocks check, sb_fdblocks may not be true,
if we have lazysbcount or not umount clean. If we check this, we need to add
if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
    XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
    !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
like function xfs_check_summary_counts does.

 fs/xfs/libxfs/xfs_alloc.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

--
2.7.4

Comments

Darrick J. Wong Feb. 21, 2020, 3:38 p.m. UTC | #1 
On Fri, Feb 21, 2020 at 12:47:15PM +0800, Zheng Bin wrote:
> We recently used fuzz(hydra) to test XFS and automatically generate
> tmp.img(XFS v5 format, but some metadata is wrong)
> 
> xfs_repair information(just one AG):
> agf_freeblks 0, counted 3224 in ag 0
> agf_longest 536874136, counted 3224 in ag 0
> sb_fdblocks 613, counted 3228
> 
> Test as follows:
> mount tmp.img tmpdir
> cp file1M tmpdir
> sync
> 
> In 4.19-stable, sync will stuck, the reason is:
> xfs_mountfs
>   xfs_check_summary_counts
>     if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
>        XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
>        !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
> 	return 0;  -->just return, incore sb_fdblocks still be 613
>     xfs_initialize_perag_data
> 
> cp file1M tmpdir -->ok(write file to pagecache)
> sync -->stuck(write pagecache to disk)
> xfs_map_blocks
>   xfs_iomap_write_allocate
>     while (count_fsb != 0) {
>       nimaps = 0;
>       while (nimaps == 0) { --> endless loop
>          nimaps = 1;
>          xfs_bmapi_write(..., &nimaps) --> nimaps becomes 0 again
> xfs_bmapi_write
>   xfs_bmap_alloc
>     xfs_bmap_btalloc
>       xfs_alloc_vextent
>         xfs_alloc_fix_freelist
>           xfs_alloc_space_available -->fail(agf_freeblks is 0)
> 
> In linux-next, sync not stuck, cause commit c2b3164320b5 ("xfs:
> use the latest extent at writeback delalloc conversion time") remove
> the above while, dmesg is as follows:
> [   55.250114] XFS (loop0): page discard on page ffffea0008bc7380, inode 0x1b0c, offset 0.
> 
> Users do not know why this page is discard, the better soultion is:
> 1. Like xfs_repair, make sure sb_fdblocks is equal to counted
> (xfs_initialize_perag_data did this, who is not called at this mount)
> 2. Add agf verify, if fail, will tell users to repair
> 
> This patch use the second soultion.
> 
> Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
> Signed-off-by: Ren Xudong <renxudong1@huawei.com>

Looks ok, will give this a run through fuzz testing...
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
> 
> v1->v2: modify comment, add more agf verify
> v2->v3: modify code which is suggested by hellwig & darrick
> besides, remove the agf_freeblks < sb_fdblocks check, sb_fdblocks may not be true,
> if we have lazysbcount or not umount clean. If we check this, we need to add
> if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
>     XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
>     !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
> like function xfs_check_summary_counts does.
> 
>  fs/xfs/libxfs/xfs_alloc.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
> index d8053bc..183dc25 100644
> --- a/fs/xfs/libxfs/xfs_alloc.c
> +++ b/fs/xfs/libxfs/xfs_alloc.c
> @@ -2858,6 +2858,13 @@ xfs_agf_verify(
>  	      be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp)))
>  		return __this_address;
> 
> +	if (be32_to_cpu(agf->agf_length) > mp->m_sb.sb_dblocks)
> +		return __this_address;
> +
> +	if (be32_to_cpu(agf->agf_freeblks) < be32_to_cpu(agf->agf_longest) ||
> +	    be32_to_cpu(agf->agf_freeblks) > be32_to_cpu(agf->agf_length))
> +		return __this_address;
> +
>  	if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 ||
>  	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) < 1 ||
>  	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) > XFS_BTREE_MAXLEVELS ||
> @@ -2869,6 +2876,10 @@ xfs_agf_verify(
>  	     be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS))
>  		return __this_address;
> 
> +	if (xfs_sb_version_hasrmapbt(&mp->m_sb) &&
> +	    be32_to_cpu(agf->agf_rmap_blocks) > be32_to_cpu(agf->agf_length))
> +		return __this_address;
> +
>  	/*
>  	 * during growfs operations, the perag is not fully initialised,
>  	 * so we can't use it for any useful checking. growfs ensures we can't
> @@ -2883,6 +2894,11 @@ xfs_agf_verify(
>  		return __this_address;
> 
>  	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
> +	    be32_to_cpu(agf->agf_refcount_blocks) >
> +	    be32_to_cpu(agf->agf_length))
> +		return __this_address;
> +
> +	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
>  	    (be32_to_cpu(agf->agf_refcount_level) < 1 ||
>  	     be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS))
>  		return __this_address;
> --
> 2.7.4
>
Zheng Bin Feb. 29, 2020, 11:21 a.m. UTC | #2 
Hi, is this ok?

On 2020/2/21 23:38, Darrick J. Wong wrote:
> On Fri, Feb 21, 2020 at 12:47:15PM +0800, Zheng Bin wrote:
>> We recently used fuzz(hydra) to test XFS and automatically generate
>> tmp.img(XFS v5 format, but some metadata is wrong)
>>
>> xfs_repair information(just one AG):
>> agf_freeblks 0, counted 3224 in ag 0
>> agf_longest 536874136, counted 3224 in ag 0
>> sb_fdblocks 613, counted 3228
>>
>> Test as follows:
>> mount tmp.img tmpdir
>> cp file1M tmpdir
>> sync
>>
>> In 4.19-stable, sync will stuck, the reason is:
>> xfs_mountfs
>>   xfs_check_summary_counts
>>     if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
>>        XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
>>        !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
>> 	return 0;  -->just return, incore sb_fdblocks still be 613
>>     xfs_initialize_perag_data
>>
>> cp file1M tmpdir -->ok(write file to pagecache)
>> sync -->stuck(write pagecache to disk)
>> xfs_map_blocks
>>   xfs_iomap_write_allocate
>>     while (count_fsb != 0) {
>>       nimaps = 0;
>>       while (nimaps == 0) { --> endless loop
>>          nimaps = 1;
>>          xfs_bmapi_write(..., &nimaps) --> nimaps becomes 0 again
>> xfs_bmapi_write
>>   xfs_bmap_alloc
>>     xfs_bmap_btalloc
>>       xfs_alloc_vextent
>>         xfs_alloc_fix_freelist
>>           xfs_alloc_space_available -->fail(agf_freeblks is 0)
>>
>> In linux-next, sync not stuck, cause commit c2b3164320b5 ("xfs:
>> use the latest extent at writeback delalloc conversion time") remove
>> the above while, dmesg is as follows:
>> [   55.250114] XFS (loop0): page discard on page ffffea0008bc7380, inode 0x1b0c, offset 0.
>>
>> Users do not know why this page is discard, the better soultion is:
>> 1. Like xfs_repair, make sure sb_fdblocks is equal to counted
>> (xfs_initialize_perag_data did this, who is not called at this mount)
>> 2. Add agf verify, if fail, will tell users to repair
>>
>> This patch use the second soultion.
>>
>> Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
>> Signed-off-by: Ren Xudong <renxudong1@huawei.com>
> Looks ok, will give this a run through fuzz testing...
> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
>
> --D
>
>> ---
>>
>> v1->v2: modify comment, add more agf verify
>> v2->v3: modify code which is suggested by hellwig & darrick
>> besides, remove the agf_freeblks < sb_fdblocks check, sb_fdblocks may not be true,
>> if we have lazysbcount or not umount clean. If we check this, we need to add
>> if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
>>     XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
>>     !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
>> like function xfs_check_summary_counts does.
>>
>>  fs/xfs/libxfs/xfs_alloc.c | 16 ++++++++++++++++
>>  1 file changed, 16 insertions(+)
>>
>> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
>> index d8053bc..183dc25 100644
>> --- a/fs/xfs/libxfs/xfs_alloc.c
>> +++ b/fs/xfs/libxfs/xfs_alloc.c
>> @@ -2858,6 +2858,13 @@ xfs_agf_verify(
>>  	      be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp)))
>>  		return __this_address;
>>
>> +	if (be32_to_cpu(agf->agf_length) > mp->m_sb.sb_dblocks)
>> +		return __this_address;
>> +
>> +	if (be32_to_cpu(agf->agf_freeblks) < be32_to_cpu(agf->agf_longest) ||
>> +	    be32_to_cpu(agf->agf_freeblks) > be32_to_cpu(agf->agf_length))
>> +		return __this_address;
>> +
>>  	if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 ||
>>  	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) < 1 ||
>>  	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) > XFS_BTREE_MAXLEVELS ||
>> @@ -2869,6 +2876,10 @@ xfs_agf_verify(
>>  	     be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS))
>>  		return __this_address;
>>
>> +	if (xfs_sb_version_hasrmapbt(&mp->m_sb) &&
>> +	    be32_to_cpu(agf->agf_rmap_blocks) > be32_to_cpu(agf->agf_length))
>> +		return __this_address;
>> +
>>  	/*
>>  	 * during growfs operations, the perag is not fully initialised,
>>  	 * so we can't use it for any useful checking. growfs ensures we can't
>> @@ -2883,6 +2894,11 @@ xfs_agf_verify(
>>  		return __this_address;
>>
>>  	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
>> +	    be32_to_cpu(agf->agf_refcount_blocks) >
>> +	    be32_to_cpu(agf->agf_length))
>> +		return __this_address;
>> +
>> +	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
>>  	    (be32_to_cpu(agf->agf_refcount_level) < 1 ||
>>  	     be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS))
>>  		return __this_address;
>> --
>> 2.7.4
>>
> .
>
Darrick J. Wong Feb. 29, 2020, 5 p.m. UTC | #3 
On Sat, Feb 29, 2020 at 07:21:17PM +0800, zhengbin (A) wrote:
> Hi, is this ok?

Yes.  I'll update for-next next week once my prepared branch finishes
running through torture testing.

--D

> On 2020/2/21 23:38, Darrick J. Wong wrote:
> > On Fri, Feb 21, 2020 at 12:47:15PM +0800, Zheng Bin wrote:
> >> We recently used fuzz(hydra) to test XFS and automatically generate
> >> tmp.img(XFS v5 format, but some metadata is wrong)
> >>
> >> xfs_repair information(just one AG):
> >> agf_freeblks 0, counted 3224 in ag 0
> >> agf_longest 536874136, counted 3224 in ag 0
> >> sb_fdblocks 613, counted 3228
> >>
> >> Test as follows:
> >> mount tmp.img tmpdir
> >> cp file1M tmpdir
> >> sync
> >>
> >> In 4.19-stable, sync will stuck, the reason is:
> >> xfs_mountfs
> >>   xfs_check_summary_counts
> >>     if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
> >>        XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
> >>        !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
> >> 	return 0;  -->just return, incore sb_fdblocks still be 613
> >>     xfs_initialize_perag_data
> >>
> >> cp file1M tmpdir -->ok(write file to pagecache)
> >> sync -->stuck(write pagecache to disk)
> >> xfs_map_blocks
> >>   xfs_iomap_write_allocate
> >>     while (count_fsb != 0) {
> >>       nimaps = 0;
> >>       while (nimaps == 0) { --> endless loop
> >>          nimaps = 1;
> >>          xfs_bmapi_write(..., &nimaps) --> nimaps becomes 0 again
> >> xfs_bmapi_write
> >>   xfs_bmap_alloc
> >>     xfs_bmap_btalloc
> >>       xfs_alloc_vextent
> >>         xfs_alloc_fix_freelist
> >>           xfs_alloc_space_available -->fail(agf_freeblks is 0)
> >>
> >> In linux-next, sync not stuck, cause commit c2b3164320b5 ("xfs:
> >> use the latest extent at writeback delalloc conversion time") remove
> >> the above while, dmesg is as follows:
> >> [   55.250114] XFS (loop0): page discard on page ffffea0008bc7380, inode 0x1b0c, offset 0.
> >>
> >> Users do not know why this page is discard, the better soultion is:
> >> 1. Like xfs_repair, make sure sb_fdblocks is equal to counted
> >> (xfs_initialize_perag_data did this, who is not called at this mount)
> >> 2. Add agf verify, if fail, will tell users to repair
> >>
> >> This patch use the second soultion.
> >>
> >> Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
> >> Signed-off-by: Ren Xudong <renxudong1@huawei.com>
> > Looks ok, will give this a run through fuzz testing...
> > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> >
> > --D
> >
> >> ---
> >>
> >> v1->v2: modify comment, add more agf verify
> >> v2->v3: modify code which is suggested by hellwig & darrick
> >> besides, remove the agf_freeblks < sb_fdblocks check, sb_fdblocks may not be true,
> >> if we have lazysbcount or not umount clean. If we check this, we need to add
> >> if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) ||
> >>     XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) &&
> >>     !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS))
> >> like function xfs_check_summary_counts does.
> >>
> >>  fs/xfs/libxfs/xfs_alloc.c | 16 ++++++++++++++++
> >>  1 file changed, 16 insertions(+)
> >>
> >> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
> >> index d8053bc..183dc25 100644
> >> --- a/fs/xfs/libxfs/xfs_alloc.c
> >> +++ b/fs/xfs/libxfs/xfs_alloc.c
> >> @@ -2858,6 +2858,13 @@ xfs_agf_verify(
> >>  	      be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp)))
> >>  		return __this_address;
> >>
> >> +	if (be32_to_cpu(agf->agf_length) > mp->m_sb.sb_dblocks)
> >> +		return __this_address;
> >> +
> >> +	if (be32_to_cpu(agf->agf_freeblks) < be32_to_cpu(agf->agf_longest) ||
> >> +	    be32_to_cpu(agf->agf_freeblks) > be32_to_cpu(agf->agf_length))
> >> +		return __this_address;
> >> +
> >>  	if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 ||
> >>  	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) < 1 ||
> >>  	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) > XFS_BTREE_MAXLEVELS ||
> >> @@ -2869,6 +2876,10 @@ xfs_agf_verify(
> >>  	     be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS))
> >>  		return __this_address;
> >>
> >> +	if (xfs_sb_version_hasrmapbt(&mp->m_sb) &&
> >> +	    be32_to_cpu(agf->agf_rmap_blocks) > be32_to_cpu(agf->agf_length))
> >> +		return __this_address;
> >> +
> >>  	/*
> >>  	 * during growfs operations, the perag is not fully initialised,
> >>  	 * so we can't use it for any useful checking. growfs ensures we can't
> >> @@ -2883,6 +2894,11 @@ xfs_agf_verify(
> >>  		return __this_address;
> >>
> >>  	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
> >> +	    be32_to_cpu(agf->agf_refcount_blocks) >
> >> +	    be32_to_cpu(agf->agf_length))
> >> +		return __this_address;
> >> +
> >> +	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
> >>  	    (be32_to_cpu(agf->agf_refcount_level) < 1 ||
> >>  	     be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS))
> >>  		return __this_address;
> >> --
> >> 2.7.4
> >>
> > .
> >
>
diff mbox series

Patch

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index d8053bc..183dc25 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2858,6 +2858,13 @@  xfs_agf_verify(
 	      be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp)))
 		return __this_address;

+	if (be32_to_cpu(agf->agf_length) > mp->m_sb.sb_dblocks)
+		return __this_address;
+
+	if (be32_to_cpu(agf->agf_freeblks) < be32_to_cpu(agf->agf_longest) ||
+	    be32_to_cpu(agf->agf_freeblks) > be32_to_cpu(agf->agf_length))
+		return __this_address;
+
 	if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 ||
 	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) < 1 ||
 	    be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) > XFS_BTREE_MAXLEVELS ||
@@ -2869,6 +2876,10 @@  xfs_agf_verify(
 	     be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS))
 		return __this_address;

+	if (xfs_sb_version_hasrmapbt(&mp->m_sb) &&
+	    be32_to_cpu(agf->agf_rmap_blocks) > be32_to_cpu(agf->agf_length))
+		return __this_address;
+
 	/*
 	 * during growfs operations, the perag is not fully initialised,
 	 * so we can't use it for any useful checking. growfs ensures we can't
@@ -2883,6 +2894,11 @@  xfs_agf_verify(
 		return __this_address;

 	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
+	    be32_to_cpu(agf->agf_refcount_blocks) >
+	    be32_to_cpu(agf->agf_length))
+		return __this_address;
+
+	if (xfs_sb_version_hasreflink(&mp->m_sb) &&
 	    (be32_to_cpu(agf->agf_refcount_level) < 1 ||
 	     be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS))
 		return __this_address;