[PATCH] orangefs: Fix possible NULL deference in orangefs_mount

[PATCH] orangefs: Fix possible NULL deference in orangefs_mount

[Su Hui]

scripts/coccinelle/null/deref_null.cocci complains:
fs/orangefs/super.c:584:18-25: ERROR:
ORANGEFS_SB ( sb ) is NULL but dereferenced.

When memory allocation for orangefs_sb_info_s fails, ORANGEFS_SB(sb)
is NULL and ORANGEFS_SB(sb)->no_list will result in NULL deference.
Add a judgement to fix this NULL deference problem.

Fixes: ac2c63757f4f ("orangefs: Fix sb refcount leak when allocate sb info failed.")
Signed-off-by: Su Hui <suhui@nfschina.com>
---
 fs/orangefs/super.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/orangefs/super.c b/fs/orangefs/super.c
index 5254256a224d..c056c86e2482 100644
--- a/fs/orangefs/super.c
+++ b/fs/orangefs/super.c
@@ -581,7 +581,8 @@ struct dentry *orangefs_mount(struct file_system_type *fst,
 
 free_sb_and_op:
 	/* Will call orangefs_kill_sb with sb not in list. */
-	ORANGEFS_SB(sb)->no_list = 1;
+	if (ORANGEFS_SB(sb))
+		ORANGEFS_SB(sb)->no_list = 1;
 	/* ORANGEFS_VFS_OP_FS_UMOUNT is done by orangefs_kill_sb. */
 	deactivate_locked_super(sb);
 free_op:
-- 
2.30.2

Re: [PATCH] orangefs: Fix possible NULL deference in orangefs_mount

[Dan Carpenter]

This was already fixed in commit:
9bf93dcfc453 ("Julia Lawall reported this null pointer dereference, this
should fix it.")

Amusing subject...  :P

regards,
dan carpenter

Re: [PATCH] orangefs: Fix possible NULL deference in orangefs_mount

[Su Hui]

On 2024/2/22 18:45, Dan Carpenter wrote:

> This was already fixed in commit:
> 9bf93dcfc453 ("Julia Lawall reported this null pointer dereference, this
> should fix it.")
>
> Amusing subject...  :P

Oh, really sorry for this. I forgot to check the linux-next git.

I'm not sure if commit 9bf93dcfc453 will lead to sb refcount leak which 
was previously fixed
by ac2c63757f4f ("orangefs: Fix sb refcount leak when allocate sb info 
failed.").

In any case, the null pointer problem has been solved.

Thanks for your reminder:)

Su Hui

Re: [PATCH] orangefs: Fix possible NULL deference in orangefs_mount

[Dan Carpenter]

On Fri, Feb 23, 2024 at 10:11:03AM +0800, Su Hui wrote:
> On 2024/2/22 18:45, Dan Carpenter wrote:
> 
> > This was already fixed in commit:
> > 9bf93dcfc453 ("Julia Lawall reported this null pointer dereference, this
> > should fix it.")
> > 
> > Amusing subject...  :P
> 
> Oh, really sorry for this. I forgot to check the linux-next git.
> 
> I'm not sure if commit 9bf93dcfc453 will lead to sb refcount leak which was
> previously fixed
> by ac2c63757f4f ("orangefs: Fix sb refcount leak when allocate sb info
> failed.").
> 

Yeah, you're right.  Do you want to re-fix that?

regards,
dan carpenter