Patch "scsi: bfa: integer overflow in debugfs" has been added to the 4.4-stable tree

Patch "scsi: bfa: integer overflow in debugfs" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    scsi: bfa: integer overflow in debugfs

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     scsi-bfa-integer-overflow-in-debugfs.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Dec 18 14:47:43 CET 2017
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 4 Oct 2017 10:50:37 +0300
Subject: scsi: bfa: integer overflow in debugfs

From: Dan Carpenter <dan.carpenter@oracle.com>


[ Upstream commit 3e351275655d3c84dc28abf170def9786db5176d ]

We could allocate less memory than intended because we do:

	bfad->regdata = kzalloc(len << 2, GFP_KERNEL);

The shift can overflow leading to a crash.  This is debugfs code so the
impact is very small.  I fixed the network version of this in March with
commit 13e2d5187f6b ("bna: integer overflow bug in debugfs").

Fixes: ab2a9ba189e8 ("[SCSI] bfa: add debugfs support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/scsi/bfa/bfad_debugfs.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/scsi/bfa/bfad_debugfs.c
+++ b/drivers/scsi/bfa/bfad_debugfs.c
@@ -254,7 +254,8 @@ bfad_debugfs_write_regrd(struct file *fi
 	struct bfad_s *bfad = port->bfad;
 	struct bfa_s *bfa = &bfad->bfa;
 	struct bfa_ioc_s *ioc = &bfa->ioc;
-	int addr, len, rc, i;
+	int addr, rc, i;
+	u32 len;
 	u32 *regbuf;
 	void __iomem *rb, *reg_addr;
 	unsigned long flags;
@@ -265,7 +266,7 @@ bfad_debugfs_write_regrd(struct file *fi
 		return PTR_ERR(kern_buf);
 
 	rc = sscanf(kern_buf, "%x:%x", &addr, &len);
-	if (rc < 2) {
+	if (rc < 2 || len > (UINT_MAX >> 2)) {
 		printk(KERN_INFO
 			"bfad[%d]: %s failed to read user buf\n",
 			bfad->inst_no, __func__);


Patches currently in stable-queue which might be from dan.carpenter@oracle.com are

queue-4.4/scsi-bfa-integer-overflow-in-debugfs.patch
queue-4.4/fbdev-controlfb-add-missing-modes-to-fix-out-of-bounds-access.patch