linux-kernel - [PATCH 5.10 23/98] scsi: megaraid_mm: Fix end of loop tests for list_for_each

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: <20210824165908.709932-24-sashal@kernel.org>
Date:   Tue, 24 Aug 2021 12:57:53 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Harshvardhan Jha <harshvardhan.jha@...cle.com>,
        Sumit Saxena <sumit.saxena@...adcom.com>,
        "Martin K . Petersen" <martin.petersen@...cle.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 23/98] scsi: megaraid_mm: Fix end of loop tests for list_for_each_entry()

From: Harshvardhan Jha <harshvardhan.jha@...cle.com>

[ Upstream commit 77541f78eadfe9fdb018a7b8b69f0f2af2cf4b82 ]

The list_for_each_entry() iterator, "adapter" in this code, can never be
NULL.  If we exit the loop without finding the correct adapter then
"adapter" points invalid memory that is an offset from the list head.  This
will eventually lead to memory corruption and presumably a kernel crash.

Link: https://lore.kernel.org/r/20210708074642.23599-1-harshvardhan.jha@oracle.com
Acked-by: Sumit Saxena <sumit.saxena@...adcom.com>
Signed-off-by: Harshvardhan Jha <harshvardhan.jha@...cle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@...cle.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/scsi/megaraid/megaraid_mm.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_mm.c b/drivers/scsi/megaraid/megaraid_mm.c
index 8df53446641a..422b726e2ac1 100644
--- a/drivers/scsi/megaraid/megaraid_mm.c
+++ b/drivers/scsi/megaraid/megaraid_mm.c
@@ -238,7 +238,7 @@ mraid_mm_get_adapter(mimd_t __user *umimd, int *rval)
 	mimd_t		mimd;
 	uint32_t	adapno;
 	int		iterator;
-
+	bool		is_found;
 
 	if (copy_from_user(&mimd, umimd, sizeof(mimd_t))) {
 		*rval = -EFAULT;
@@ -254,12 +254,16 @@ mraid_mm_get_adapter(mimd_t __user *umimd, int *rval)
 
 	adapter = NULL;
 	iterator = 0;
+	is_found = false;
 
 	list_for_each_entry(adapter, &adapters_list_g, list) {
-		if (iterator++ == adapno) break;
+		if (iterator++ == adapno) {
+			is_found = true;
+			break;
+		}
 	}
 
-	if (!adapter) {
+	if (!is_found) {
 		*rval = -ENODEV;
 		return NULL;
 	}
@@ -725,6 +729,7 @@ ioctl_done(uioc_t *kioc)
 	uint32_t	adapno;
 	int		iterator;
 	mraid_mmadp_t*	adapter;
+	bool		is_found;
 
 	/*
 	 * When the kioc returns from driver, make sure it still doesn't
@@ -747,19 +752,23 @@ ioctl_done(uioc_t *kioc)
 		iterator	= 0;
 		adapter		= NULL;
 		adapno		= kioc->adapno;
+		is_found	= false;
 
 		con_log(CL_ANN, ( KERN_WARNING "megaraid cmm: completed "
 					"ioctl that was timedout before\n"));
 
 		list_for_each_entry(adapter, &adapters_list_g, list) {
-			if (iterator++ == adapno) break;
+			if (iterator++ == adapno) {
+				is_found = true;
+				break;
+			}
 		}
 
 		kioc->timedout = 0;
 
-		if (adapter) {
+		if (is_found)
 			mraid_mm_dealloc_kioc( adapter, kioc );
-		}
+
 	}
 	else {
 		wake_up(&wait_q);
-- 
2.30.2