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: <20230504194142.3805425-10-sashal@kernel.org>
Date:   Thu,  4 May 2023 15:40:53 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Justin Tee <justin.tee@...adcom.com>,
        "Martin K . Petersen" <martin.petersen@...cle.com>,
        Sasha Levin <sashal@...nel.org>, james.smart@...adcom.com,
        dick.kennedy@...adcom.com, jejb@...ux.ibm.com,
        linux-scsi@...r.kernel.org
Subject: [PATCH AUTOSEL 6.3 10/59] scsi: lpfc: Prevent lpfc_debugfs_lockstat_write() buffer overflow

From: Justin Tee <justin.tee@...adcom.com>

[ Upstream commit c6087b82a9146826564a55c5ca0164cac40348f5 ]

A static code analysis tool flagged the possibility of buffer overflow when
using copy_from_user() for a debugfs entry.

Currently, it is possible that copy_from_user() copies more bytes than what
would fit in the mybuf char array.  Add a min() restriction check between
sizeof(mybuf) - 1 and nbytes passed from the userspace buffer to protect
against buffer overflow.

Link: https://lore.kernel.org/r/20230301231626.9621-2-justintee8345@gmail.com
Signed-off-by: Justin Tee <justin.tee@...adcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@...cle.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/scsi/lpfc/lpfc_debugfs.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index f5252e45a48a2..3e365e5e194a2 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -2157,10 +2157,13 @@ lpfc_debugfs_lockstat_write(struct file *file, const char __user *buf,
 	char mybuf[64];
 	char *pbuf;
 	int i;
+	size_t bsize;
 
 	memset(mybuf, 0, sizeof(mybuf));
 
-	if (copy_from_user(mybuf, buf, nbytes))
+	bsize = min(nbytes, (sizeof(mybuf) - 1));
+
+	if (copy_from_user(mybuf, buf, bsize))
 		return -EFAULT;
 	pbuf = &mybuf[0];
 
@@ -2181,7 +2184,7 @@ lpfc_debugfs_lockstat_write(struct file *file, const char __user *buf,
 			qp->lock_conflict.wq_access = 0;
 		}
 	}
-	return nbytes;
+	return bsize;
 }
 #endif
 
-- 
2.39.2

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ