opensc: Fix CVE-2023-2977

A vulnerbility was found in OpenSC. This security flaw cause a buffer overrun
vulnerability in pkcs15 cardos_have_verifyrc_package. The attacker can supply
a smart card package with malformed ASN1 context. The cardos_have_verifyrc_package
function scans the ASN1 buffer for 2 tags, where remaining length is wrongly
caculated due to moved starting pointer. This leads to possible heap-based buffer
oob read. In cases where ASAN is enabled while compiling this causes a crash.
Further info leak or more damage is possible.

Signed-off-by: Soumya <soumya.sambu@windriver.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

2 files changed, 54 insertions, 0 deletions

diff --git a/meta-oe/recipes-support/opensc/files/CVE-2023-2977.patch b/meta-oe/recipes-support/opensc/files/CVE-2023-2977.patch
new file mode 100644
index 0000000000..6a635a7ce6
--- /dev/null
+++ b/meta-oe/recipes-support/opensc/files/CVE-2023-2977.patch
@@ -0,0 +1,53 @@
+commit 81944d1529202bd28359bede57c0a15deb65ba8a
+Author: fullwaywang <fullwaywang@tencent.com>
+Date:   Mon May 29 10:38:48 2023 +0800
+Subject: [PATCH] pkcs15init: correct left length calculation to fix buffer overrun bug.
+
+    Fixes #2785
+
+CVE: CVE-2023-2977
+
+Upstream-Status: Backport [https://github.com/OpenSC/OpenSC/pull/2787/commits/3bf3ab2f9091f984cda6dd910654ccbbe3f06a40]
+
+Signed-off-by: Soumya <soumya.sambu@windriver.com>
+---
+
+diff --git a/src/pkcs15init/pkcs15-cardos.c b/src/pkcs15init/pkcs15-cardos.c
+index 9715cf39..f41f73c3 100644
+--- a/src/pkcs15init/pkcs15-cardos.c
++++ b/src/pkcs15init/pkcs15-cardos.c
+@@ -872,7 +872,7 @@ static int cardos_have_verifyrc_package(sc_card_t *card)
+        sc_apdu_t apdu;
+         u8        rbuf[SC_MAX_APDU_BUFFER_SIZE];
+         int       r;
+-       const u8  *p = rbuf, *q;
++       const u8  *p = rbuf, *q, *pp;
+        size_t    len, tlen = 0, ilen = 0;
+
+        sc_format_apdu(card, &apdu, SC_APDU_CASE_2_SHORT, 0xca, 0x01, 0x88);
+@@ -888,13 +888,13 @@ static int cardos_have_verifyrc_package(sc_card_t *card)
+                return 0;
+
+        while (len != 0) {
+-               p = sc_asn1_find_tag(card->ctx, p, len, 0xe1, &tlen);
+-               if (p == NULL)
++               pp = sc_asn1_find_tag(card->ctx, p, len, 0xe1, &tlen);
++               if (pp == NULL)
+                        return 0;
+                if (card->type == SC_CARD_TYPE_CARDOS_M4_3)     {
+                        /* the verifyRC package on CardOS 4.3B use Manufacturer ID 0x01 */
+                        /* and Package Number 0x07                                      */
+-                       q = sc_asn1_find_tag(card->ctx, p, tlen, 0x01, &ilen);
++                       q = sc_asn1_find_tag(card->ctx, pp, tlen, 0x01, &ilen);
+                        if (q == NULL || ilen != 4)
+                                return 0;
+                        if (q[0] == 0x07)
+@@ -902,7 +902,7 @@ static int cardos_have_verifyrc_package(sc_card_t *card)
+                } else if (card->type == SC_CARD_TYPE_CARDOS_M4_4)      {
+                        /* the verifyRC package on CardOS 4.4 use Manufacturer ID 0x03  */
+                        /* and Package Number 0x02                                      */
+-                       q = sc_asn1_find_tag(card->ctx, p, tlen, 0x03, &ilen);
++                       q = sc_asn1_find_tag(card->ctx, pp, tlen, 0x03, &ilen);
+                        if (q == NULL || ilen != 4)
+                                return 0;
+                        if (q[0] == 0x02)
diff --git a/meta-oe/recipes-support/opensc/opensc_0.22.0.bb b/meta-oe/recipes-support/opensc/opensc_0.22.0.bb
index f8b4af0c4f..4590b85fa4 100644
--- a/meta-oe/recipes-support/opensc/opensc_0.22.0.bb
+++ b/meta-oe/recipes-support/opensc/opensc_0.22.0.bb
@@ -14,6 +14,7 @@ LIC_FILES_CHKSUM = "file://COPYING;md5=cb8aedd3bced19bd8026d96a8b6876d7"
 #v0.21.0
 SRCREV = "c902e1992195e00ada12d71beb1029287cd72037"
 SRC_URI = "git://github.com/OpenSC/OpenSC;branch=master;protocol=https \
+           file://CVE-2023-2977.patch \
           "
 DEPENDS = "virtual/libiconv openssl"