[LU-7077] Pointer 'hash' returned from call to function 'cfs_hash_getref' may be NULL and will be dereferenced.

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.8.0
• Labels: kw
• Severity: 3
• Assignee: Bob Glossman (Inactive)
• Reporter: Dmitry Eremin (Inactive)

Description

lustre/obdclass/genops.c:944

hash = cfs_hash_getref(exp->exp_obd->obd_gen_hash);
cfs_hash_del(hash, &ted->ted_lcd->lcd_generation,
	     &exp->exp_gen_hash);
cfs_hash_putref(hash);

struct cfs_hash *cfs_hash_getref(struct cfs_hash *hs)
{
	if (atomic_inc_not_zero(&hs->hs_refcount))
		return hs;
	return NULL;
}

Issue Links

• is related to: LU-6840 update memory reply data in DNE update replay

Comments

[Joseph Gmitter (Inactive)]

Landed for 2.8

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/16473/
Subject: LU-7077 target: avoid using possible error return NULL pointer
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: a7eface85ea2d2aa6198681264b082a0244855d4

[Dmitry Eremin (Inactive)]

This issue was found by static analysis checker. So, we didn't get a real crash because of it. The question is can we gracefully handle errors or not.

[Di Wang]

Dmitry, could you please comment on http://review.whamcloud.com/#/c/16473/1 ? thanks

[Gerrit Updater]

Bob Glossman ([e-mail]) uploaded a new patch: http://review.whamcloud.com/16473
Subject: LU-7077 target: avoid using possible error return NULL pointer
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: fa02a91e622631096b83021d31b0aa6781950662

[Dmitry Eremin (Inactive)]

This was introduced in http://review.whamcloud.com/15576