Re: [PATCH] smackfs: use netlbl_cfg_cipsov4_del() for deleting cipso_v4_doi
From: Casey Schaufler <casey@schaufler-ca.com>
Date: 2021-10-22 18:02:30
On 10/19/2021 4:27 AM, Tetsuo Handa wrote:
syzbot is reporting UAF at cipso_v4_doi_search() [1], for smk_cipso_doi() is calling kfree() without removing from the cipso_v4_doi_list list after netlbl_cfg_cipsov4_map_add() returned an error. We need to use netlbl_cfg_cipsov4_del() in order to remove from the list and wait for RCU grace period before kfree(). Link: https://syzkaller.appspot.com/bug?extid=93dba5b91f0fed312cbd [1] Reported-by: syzbot <redacted> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fixes: 6c2e8ac0953fccdd ("netlabel: Update kernel configuration API")
Added to smack-next. Thank you.
quoted hunk ↗ jump to hunk
--- security/smack/smackfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 3a75d2a8f517..83b90442f963 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c@@ -714,7 +714,7 @@ static void smk_cipso_doi(void) if (rc != 0) { printk(KERN_WARNING "%s:%d map add rc = %d\n", __func__, __LINE__, rc); - kfree(doip); + netlbl_cfg_cipsov4_del(doip->doi, &nai); return; } }