Patch "pkcs7: Prevent NULL pointer dereference, since sinfo is not always set." has been added to the 4.4-stable tree

Patch "pkcs7: Prevent NULL pointer dereference, since sinfo is not always set." 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

    pkcs7: Prevent NULL pointer dereference, since sinfo is not always set.

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:
     pkcs7-prevent-null-pointer-dereference-since-sinfo-is-not-always-set.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 68a1fdbbf8bd3378325e45c19e167a165f9ffc3a Mon Sep 17 00:00:00 2001
From: Eric Sesterhenn <eric.sesterhenn@x41-dsec.de>
Date: Sun, 8 Oct 2017 20:02:32 +0200
Subject: pkcs7: Prevent NULL pointer dereference, since sinfo is not always set.

From: Eric Sesterhenn <eric.sesterhenn@x41-dsec.de>

commit 68a1fdbbf8bd3378325e45c19e167a165f9ffc3a upstream.

The ASN.1 parser does not necessarily set the sinfo field,
this patch prevents a NULL pointer dereference on broken
input.

Fixes: 99db44350672 ("PKCS#7: Appropriately restrict authenticated attributes and content type")
Signed-off-by: Eric Sesterhenn <eric.sesterhenn@x41-dsec.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 crypto/asymmetric_keys/pkcs7_parser.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/crypto/asymmetric_keys/pkcs7_parser.c
+++ b/crypto/asymmetric_keys/pkcs7_parser.c
@@ -90,6 +90,9 @@ static int pkcs7_check_authattrs(struct
 	bool want;
 
 	sinfo = msg->signed_infos;
+	if (!sinfo)
+		goto inconsistent;
+
 	if (sinfo->authattrs) {
 		want = true;
 		msg->have_authattrs = true;


Patches currently in stable-queue which might be from eric.sesterhenn@x41-dsec.de are

queue-4.4/pkcs7-prevent-null-pointer-dereference-since-sinfo-is-not-always-set.patch