All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH v2] ocfs2: Fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume()
  2024-08-19  2:52   ` Joseph Qi
@ 2024-08-20  1:03     ` qasdev
  2024-08-20  1:12       ` Joseph Qi
  0 siblings, 1 reply; 4+ messages in thread
From: qasdev @ 2024-08-20  1:03 UTC (permalink / raw)
  To: Joseph Qi, Heming Zhao, mark, jlbec; +Cc: ocfs2-devel, linux-kernel

On Mon, Aug 19, 2024 at 10:52:29AM +0800, Joseph Qi wrote:
> 
> 
> On 8/18/24 7:43 PM, Heming Zhao wrote:
> > On 8/16/24 21:41, qasdev wrote:
> >>  From ad1ca2fd2ecf4eb7ec2c76fcbbf34639f0ad87ca Mon Sep 17 00:00:00 2001
> >> From: Qasim Ijaz <qasdev00@gmail.com>
> >> Date: Fri, 16 Aug 2024 02:30:25 +0100
> >> Subject: [PATCH] ocfs2: Fix shift-out-of-bounds UBSAN bug in
> >>   ocfs2_verify_volume()
> >>
> 
> The above should be eliminated from patch body. 
> 
> >> This patch addresses a shift-out-of-bounds error in the
> >> ocfs2_verify_volume() function, identified by UBSAN. The bug was triggered
> >> by an invalid s_clustersize_bits value (e.g., 1548), which caused the
> >> expression "1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits)"
> >> to exceed the limits of a 32-bit integer,
> >> leading to an out-of-bounds shift.
> >>
> >> Reported-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
> >> Closes: https://syzkaller.appspot.com/bug?extid=f3fff775402751ebb471
> >> Tested-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
> >> Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
> >> ---
> >>   fs/ocfs2/super.c | 8 ++++++--
> >>   1 file changed, 6 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
> >> index afee70125ae3..1e43cdca7f40 100644
> >> --- a/fs/ocfs2/super.c
> >> +++ b/fs/ocfs2/super.c
> >> @@ -2357,8 +2357,12 @@ static int ocfs2_verify_volume(struct ocfs2_dinode *di,
> >>                    (unsigned long long)bh->b_blocknr);
> >>           } else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
> >>                   le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
> >> -            mlog(ML_ERROR, "bad cluster size found: %u\n",
> >> -                 1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
> >> +            if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 32)
> >> +                mlog(ML_ERROR, "bad cluster size found: %u\n",
> >> +                     1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
> >> +            else
> >> +                mlog(ML_ERROR, "invalid cluster size bit value: %u\n",
> >> +                     le32_to_cpu(di->id2.i_super.s_clustersize_bits));
> > 
> > I prefer to use concise code to fix the error.
> > Do you like below code?
> > -        mlog(ML_ERROR, "bad cluster size found: %u\n",
> > -                 1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
> > +        mlog(ML_ERROR, "bad cluster size bit found: %u\n",
> > +                 le32_to_cpu(di->id2.i_super.s_clustersize_bits));
> > 
> 
> Agree. qasdev, Could you please update and send v2?
> 
> Thanks,
> Joseph

Thanks for the feedback. After considering the input, I've refined the patch 
to make it more concise. I've updated the patch and included it below:


This patch addresses a shift-out-of-bounds error in the 
ocfs2_verify_volume() function, identified by UBSAN. The bug was triggered 
by an invalid s_clustersize_bits value (e.g., 1548), which caused the 
expression "1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits)" 
to exceed the limits of a 32-bit integer, 
leading to an out-of-bounds shift.

Reported-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=f3fff775402751ebb471
Tested-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
---
 fs/ocfs2/super.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index afee70125ae3..b704983b2112 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -2357,8 +2357,8 @@ static int ocfs2_verify_volume(struct ocfs2_dinode *di,
                     (unsigned long long)bh->b_blocknr);
             } else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
                     le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
-                   mlog(ML_ERROR, "bad cluster size found: %u\n",
-                        1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
+                   mlog(ML_ERROR, "bad cluster size bit found: %u\n",
+                        le32_to_cpu(di->id2.i_super.s_clustersize_bits));
             } else if (!le64_to_cpu(di->id2.i_super.s_root_blkno)) {
                     mlog(ML_ERROR, "bad root_blkno: 0\n");
             } else if (!le64_to_cpu(di->id2.i_super.s_system_dir_blkno)) {
-- 
2.30.2

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH v2] ocfs2: Fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume()
  2024-08-20  1:03     ` [PATCH v2] " qasdev
@ 2024-08-20  1:12       ` Joseph Qi
  0 siblings, 0 replies; 4+ messages in thread
From: Joseph Qi @ 2024-08-20  1:12 UTC (permalink / raw)
  To: qasdev, Heming Zhao, mark, jlbec; +Cc: ocfs2-devel, linux-kernel



On 8/20/24 9:03 AM, qasdev wrote:
> On Mon, Aug 19, 2024 at 10:52:29AM +0800, Joseph Qi wrote:
>>
>>
>> On 8/18/24 7:43 PM, Heming Zhao wrote:
>>> On 8/16/24 21:41, qasdev wrote:
>>>>  From ad1ca2fd2ecf4eb7ec2c76fcbbf34639f0ad87ca Mon Sep 17 00:00:00 2001
>>>> From: Qasim Ijaz <qasdev00@gmail.com>
>>>> Date: Fri, 16 Aug 2024 02:30:25 +0100
>>>> Subject: [PATCH] ocfs2: Fix shift-out-of-bounds UBSAN bug in
>>>>   ocfs2_verify_volume()
>>>>
>>
>> The above should be eliminated from patch body. 
>>
>>>> This patch addresses a shift-out-of-bounds error in the
>>>> ocfs2_verify_volume() function, identified by UBSAN. The bug was triggered
>>>> by an invalid s_clustersize_bits value (e.g., 1548), which caused the
>>>> expression "1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits)"
>>>> to exceed the limits of a 32-bit integer,
>>>> leading to an out-of-bounds shift.
>>>>
>>>> Reported-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
>>>> Closes: https://syzkaller.appspot.com/bug?extid=f3fff775402751ebb471
>>>> Tested-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
>>>> Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
>>>> ---
>>>>   fs/ocfs2/super.c | 8 ++++++--
>>>>   1 file changed, 6 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
>>>> index afee70125ae3..1e43cdca7f40 100644
>>>> --- a/fs/ocfs2/super.c
>>>> +++ b/fs/ocfs2/super.c
>>>> @@ -2357,8 +2357,12 @@ static int ocfs2_verify_volume(struct ocfs2_dinode *di,
>>>>                    (unsigned long long)bh->b_blocknr);
>>>>           } else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
>>>>                   le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
>>>> -            mlog(ML_ERROR, "bad cluster size found: %u\n",
>>>> -                 1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
>>>> +            if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 32)
>>>> +                mlog(ML_ERROR, "bad cluster size found: %u\n",
>>>> +                     1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
>>>> +            else
>>>> +                mlog(ML_ERROR, "invalid cluster size bit value: %u\n",
>>>> +                     le32_to_cpu(di->id2.i_super.s_clustersize_bits));
>>>
>>> I prefer to use concise code to fix the error.
>>> Do you like below code?
>>> -        mlog(ML_ERROR, "bad cluster size found: %u\n",
>>> -                 1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
>>> +        mlog(ML_ERROR, "bad cluster size bit found: %u\n",
>>> +                 le32_to_cpu(di->id2.i_super.s_clustersize_bits));
>>>
>>
>> Agree. qasdev, Could you please update and send v2?
>>
>> Thanks,
>> Joseph
> 
> Thanks for the feedback. After considering the input, I've refined the patch 
> to make it more concise. I've updated the patch and included it below:
> 
Hi, please send v2 as a standalone thread.

Thanks,
Joseph

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH v2] ocfs2: Fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume()
@ 2024-08-20  1:22 qasdev
  2024-08-20  1:27 ` Joseph Qi
  0 siblings, 1 reply; 4+ messages in thread
From: qasdev @ 2024-08-20  1:22 UTC (permalink / raw)
  To: mark, jlbec, joseph.qi; +Cc: ocfs2-devel, linux-kernel

This patch addresses a shift-out-of-bounds error in the
ocfs2_verify_volume() function, identified by UBSAN. The bug was triggered
by an invalid s_clustersize_bits value (e.g., 1548), which caused the
expression "1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits)"
to exceed the limits of a 32-bit integer,
leading to an out-of-bounds shift.

Reported-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=f3fff775402751ebb471
Tested-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>
---
 fs/ocfs2/super.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index afee70125ae3..b704983b2112 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -2357,8 +2357,8 @@ static int ocfs2_verify_volume(struct ocfs2_dinode *di,
 			     (unsigned long long)bh->b_blocknr);
 		} else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
 			    le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
-			mlog(ML_ERROR, "bad cluster size found: %u\n",
-			     1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
+			mlog(ML_ERROR, "bad cluster size bit found: %u\n",
+			     le32_to_cpu(di->id2.i_super.s_clustersize_bits));
 		} else if (!le64_to_cpu(di->id2.i_super.s_root_blkno)) {
 			mlog(ML_ERROR, "bad root_blkno: 0\n");
 		} else if (!le64_to_cpu(di->id2.i_super.s_system_dir_blkno)) {
-- 
2.30.2

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH v2] ocfs2: Fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume()
  2024-08-20  1:22 [PATCH v2] ocfs2: Fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume() qasdev
@ 2024-08-20  1:27 ` Joseph Qi
  0 siblings, 0 replies; 4+ messages in thread
From: Joseph Qi @ 2024-08-20  1:27 UTC (permalink / raw)
  To: qasdev, mark, jlbec, akpm; +Cc: ocfs2-devel, linux-kernel



On 8/20/24 9:22 AM, qasdev wrote:
> This patch addresses a shift-out-of-bounds error in the
> ocfs2_verify_volume() function, identified by UBSAN. The bug was triggered
> by an invalid s_clustersize_bits value (e.g., 1548), which caused the
> expression "1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits)"
> to exceed the limits of a 32-bit integer,
> leading to an out-of-bounds shift.
> 
> Reported-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
> Closes: https://syzkaller.appspot.com/bug?extid=f3fff775402751ebb471
> Tested-by: syzbot <syzbot+f3fff775402751ebb471@syzkaller.appspotmail.com>
> Signed-off-by: Qasim Ijaz <qasdev00@gmail.com>

Looks fine.
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
> ---
>  fs/ocfs2/super.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
> index afee70125ae3..b704983b2112 100644
> --- a/fs/ocfs2/super.c
> +++ b/fs/ocfs2/super.c
> @@ -2357,8 +2357,8 @@ static int ocfs2_verify_volume(struct ocfs2_dinode *di,
>  			     (unsigned long long)bh->b_blocknr);
>  		} else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
>  			    le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
> -			mlog(ML_ERROR, "bad cluster size found: %u\n",
> -			     1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
> +			mlog(ML_ERROR, "bad cluster size bit found: %u\n",
> +			     le32_to_cpu(di->id2.i_super.s_clustersize_bits));
>  		} else if (!le64_to_cpu(di->id2.i_super.s_root_blkno)) {
>  			mlog(ML_ERROR, "bad root_blkno: 0\n");
>  		} else if (!le64_to_cpu(di->id2.i_super.s_system_dir_blkno)) {

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2024-08-20  1:27 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-08-20  1:22 [PATCH v2] ocfs2: Fix shift-out-of-bounds UBSAN bug in ocfs2_verify_volume() qasdev
2024-08-20  1:27 ` Joseph Qi
  -- strict thread matches above, loose matches on Subject: below --
2024-08-16 13:41 [PATCH] " qasdev
2024-08-18 11:43 ` Heming Zhao
2024-08-19  2:52   ` Joseph Qi
2024-08-20  1:03     ` [PATCH v2] " qasdev
2024-08-20  1:12       ` Joseph Qi

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.