Add fix for CVE-2022-23645

Fixes: rhbz#2056518

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

0001-swtpm-Check-header-size-indicator-against-expected-s.patch

@@ -0,0 +1,54 @@
+From 9f740868fc36761de27df3935513bdebf8852d19 Mon Sep 17 00:00:00 2001
+From: Stefan Berger <stefanb@linux.ibm.com>
+Date: Wed, 16 Feb 2022 11:17:47 -0500
+Subject: [PATCH] swtpm: Check header size indicator against expected size (CID
+ 375869)
+
+This fix addresses Coverity issue CID 375869.
+
+Check the header size indicated in the header of the state against the
+expected size and return an error code in case the header size indicator
+is different. There was only one header size so far since blobheader was
+introduced, so we don't need to deal with different sizes.
+
+Without this fix a specially craft header could have cause out-of-bounds
+accesses on the byte array containing the swtpm's state.
+
+Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
+---
+ src/swtpm/swtpm_nvstore.c | 11 ++++++++++-
+ 1 file changed, 10 insertions(+), 1 deletion(-)
+
+diff --git a/src/swtpm/swtpm_nvstore.c b/src/swtpm/swtpm_nvstore.c
+index 437088370e11..144d8975ec54 100644
+--- a/src/swtpm/swtpm_nvstore.c
++++ b/src/swtpm/swtpm_nvstore.c
+@@ -1075,6 +1075,7 @@ SWTPM_NVRAM_CheckHeader(unsigned char *data, uint32_t length,
+                         uint8_t *hdrversion, bool quiet)
+ {
+     blobheader *bh = (blobheader *)data;
++    uint16_t hdrsize;
+ 
+     if (length < sizeof(bh)) {
+         if (!quiet)
+@@ -1100,8 +1101,16 @@ SWTPM_NVRAM_CheckHeader(unsigned char *data, uint32_t length,
+         return TPM_BAD_VERSION;
+     }
+ 
++    hdrsize = ntohs(bh->hdrsize);
++    if (hdrsize != sizeof(blobheader)) {
++        logprintf(STDERR_FILENO,
++                  "bad header size: %u != %zu\n",
++                  hdrsize, sizeof(blobheader));
++        return TPM_BAD_DATASIZE;
++    }
++
+     *hdrversion = bh->version;
+-    *dataoffset = ntohs(bh->hdrsize);
++    *dataoffset = hdrsize;
+     *hdrflags = ntohs(bh->flags);
+ 
+     return TPM_SUCCESS;
+-- 
+2.34.1.428.gdcc0cd074f0c
+

swtpm.spec

@@ -12,10 +12,11 @@
 Summary: TPM Emulator
 Name:           swtpm
 Version:        0.7.0
-Release:        1.%{gitdate}git%{gitshortcommit}%{?dist}
+Release:        2.%{gitdate}git%{gitshortcommit}%{?dist}
 License:        BSD
 Url:            http://github.com/stefanberger/swtpm
 Source0:        %{url}/archive/%{gitcommit}/%{name}-%{gitshortcommit}.tar.gz
+Patch0001:      0001-swtpm-Check-header-size-indicator-against-expected-s.patch
 
 BuildRequires: make
 BuildRequires:  git-core
@@ -178,6 +179,10 @@ fi
 %{_datadir}/swtpm/swtpm-create-tpmca
 
 %changelog
+* Mon Feb 21 2022 Marc-André Lureau <marcandre.lureau@redhat.com> - 0.7.0-2.20211109gitb79fd91
+- Add fix for CVE-2022-23645.
+  Resolves: rhbz#2056518
+
 * Fri Nov 12 2021 Marc-André Lureau <marcandre.lureau@redhat.com> - 0.7.0-1.20211109gitb79fd91
 - Update to v0.7.0 release
   Resolves: rhbz#2021580 & rhbz#1990153