linux-kernel - [PATCH v4 3/4] mm/mempolicy: return EINVAL if len overflows for mbind

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230320024739.224850-4-mawupeng1@huawei.com>
Date:   Mon, 20 Mar 2023 10:47:38 +0800
From:   Wupeng Ma <mawupeng1@...wei.com>
To:     <akpm@...ux-foundation.org>
CC:     <linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>,
        <mawupeng1@...wei.com>, <kuleshovmail@...il.com>,
        <aneesh.kumar@...ux.ibm.com>, <david@...hat.com>
Subject: [PATCH v4 3/4] mm/mempolicy: return EINVAL if len overflows for mbind

From: Ma Wupeng <mawupeng1@...wei.com>

Return -EINVAL if len overflows for mbind.

Signed-off-by: Ma Wupeng <mawupeng1@...wei.com>
---
 mm/mempolicy.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 3a68998adc3a..6b1c45021e48 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1259,6 +1259,7 @@ static long do_mbind(unsigned long start, unsigned long len,
 		     nodemask_t *nmask, unsigned long flags)
 {
 	struct mm_struct *mm = current->mm;
+	unsigned long old_len = len;
 	struct mempolicy *new;
 	unsigned long end;
 	int err;
@@ -1279,7 +1280,7 @@ static long do_mbind(unsigned long start, unsigned long len,
 	len = PAGE_ALIGN(len);
 	end = start + len;
 
-	if (end < start)
+	if (end < start || (old_len != 0 && len == 0))
 		return -EINVAL;
 	if (end == start)
 		return 0;
-- 
2.25.1