CVE-2015-5327 x509 time validation

2 files changed, 91 insertions, 0 deletions

diff --git a/X.509-Fix-the-time-validation-ver-3.patch b/X.509-Fix-the-time-validation-ver-3.patch
new file mode 100644
index 000000000..40c50c9ec
--- /dev/null
+++ b/X.509-Fix-the-time-validation-ver-3.patch
@@ -0,0 +1,85 @@
+From 7db4b65eb11683e19ecb607501fa96a8cfac835f Mon Sep 17 00:00:00 2001
+From: David Howells <dhowells@redhat.com>
+Date: Thu, 12 Nov 2015 11:38:40 +0000
+Subject: [PATCH] X.509: Fix the time validation [ver #3]
+
+This fixes CVE-2015-5327.  It affects kernels from 4.3-rc1 onwards.
+
+Fix the X.509 time validation to use month number-1 when looking up the
+number of days in that month.  Also put the month number validation before
+doing the lookup so as not to risk overrunning the array.
+
+This can be tested by doing the following:
+
+cat <<EOF | openssl x509 -outform DER | keyctl padd asymmetric "" @s
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+EOF
+
+If the patch works, the above should emit a key ID from the new key being
+accepted; without the patch, it will give a bad message error.
+
+Reported-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
+Acked-by: David Woodhouse <David.Woodhouse@intel.com>
+---
+ crypto/asymmetric_keys/x509_cert_parser.c | 12 +++++++-----
+ 1 file changed, 7 insertions(+), 5 deletions(-)
+
+diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
+index 3000ea3b6687..021d39c0ba75 100644
+--- a/crypto/asymmetric_keys/x509_cert_parser.c
++++ b/crypto/asymmetric_keys/x509_cert_parser.c
+@@ -531,7 +531,11 @@ int x509_decode_time(time64_t *_t,  size_t hdrlen,
+ 	if (*p != 'Z')
+ 		goto unsupported_time;
+ 
+-	mon_len = month_lengths[mon];
++	if (year < 1970 ||
++	    mon < 1 || mon > 12)
++		goto invalid_time;
++
++	mon_len = month_lengths[mon - 1];
+ 	if (mon == 2) {
+ 		if (year % 4 == 0) {
+ 			mon_len = 29;
+@@ -543,14 +547,12 @@ int x509_decode_time(time64_t *_t,  size_t hdrlen,
+ 		}
+ 	}
+ 
+-	if (year < 1970 ||
+-	    mon < 1 || mon > 12 ||
+-	    day < 1 || day > mon_len ||
++	if (day < 1 || day > mon_len ||
+ 	    hour > 23 ||
+ 	    min > 59 ||
+ 	    sec > 59)
+ 		goto invalid_time;
+-	
++
+ 	*_t = mktime64(year, mon, day, hour, min, sec);
+ 	return 0;
+ 
+-- 
+2.4.3
+
diff --git a/kernel.spec b/kernel.spec
index 9719c3458..99729cfbb 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -600,6 +600,9 @@ Patch552: megaraid_sas-Do-not-use-PAGE_SIZE-for-max_sectors.patch
 #rhbz 1275490
 Patch553: ideapad-laptop-Add-Lenovo-Yoga-900-to-no_hw_rfkill-d.patch
 
+#CVE-2015-5327
+Patch554: X.509-Fix-the-time-validation-ver-3.patch
+
 # END OF PATCH DEFINITIONS
 
 %endif
@@ -2043,6 +2046,9 @@ fi
 #
 # 
 %changelog
+* Thu Nov 12 2015 Josh Boyer <jwboyer@fedoraproject.org>
+- CVE-2015-5327 x509 time validation
+
 * Wed Nov 11 2015 Laura Abbott <labbott@redhat.com> - 4.4.0-0.rc0.git7.2
 - Drop CONFIG_DRM_DW_HDMI_AHB_AUDIO for now