file: fix CVE-2019-18218

(From OE-Core rev: 626f518df57868250ea467532b8cf2968d78df6d)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 57 insertions, 1 deletions

diff --git a/meta/recipes-devtools/file/file/CVE-2019-18218.patch b/meta/recipes-devtools/file/file/CVE-2019-18218.patch
new file mode 100644
index 0000000000..3d02c5ad4b
--- /dev/null
+++ b/meta/recipes-devtools/file/file/CVE-2019-18218.patch
@@ -0,0 +1,55 @@
+cdf_read_property_info in cdf.c in file through 5.37 does not restrict the
+number of CDF_VECTOR elements, which allows a heap-based buffer overflow (4-byte
+out-of-bounds write).
+
+CVE: CVE-2019-18218
+Upstream-Status: Backport
+Signed-off-by: Ross Burton <ross.burton@intel.com>
+
+From 46a8443f76cec4b41ec736eca396984c74664f84 Mon Sep 17 00:00:00 2001
+From: Christos Zoulas <christos@zoulas.com>
+Date: Mon, 26 Aug 2019 14:31:39 +0000
+Subject: [PATCH] Limit the number of elements in a vector (found by oss-fuzz)
+
+---
+ src/cdf.c | 9 ++++-----
+ src/cdf.h | 1 +
+ 2 files changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/src/cdf.c b/src/cdf.c
+index 9d6396742..bb81d6374 100644
+--- a/src/cdf.c
++++ b/src/cdf.c
+@@ -1016,8 +1016,9 @@ cdf_read_property_info(const cdf_stream_t *sst, const cdf_header_t *h,
+                                goto out;
+                        }
+                        nelements = CDF_GETUINT32(q, 1);
+-                       if (nelements == 0) {
+-                               DPRINTF(("CDF_VECTOR with nelements == 0\n"));
++                       if (nelements > CDF_ELEMENT_LIMIT || nelements == 0) {
++                               DPRINTF(("CDF_VECTOR with nelements == %"
++                                   SIZE_T_FORMAT "u\n", nelements));
+                                goto out;
+                        }
+                        slen = 2;
+@@ -1060,8 +1061,6 @@ cdf_read_property_info(const cdf_stream_t *sst, const cdf_header_t *h,
+                                        goto out;
+                                inp += nelem;
+                        }
+-                       DPRINTF(("nelements = %" SIZE_T_FORMAT "u\n",
+-                           nelements));
+                        for (j = 0; j < nelements && i < sh.sh_properties;
+                            j++, i++)
+                        {
+diff --git a/src/cdf.h b/src/cdf.h
+index 2f7e554b7..05056668f 100644
+--- a/src/cdf.h
++++ b/src/cdf.h
+@@ -48,6 +48,7 @@
+ typedef int32_t cdf_secid_t;
+ 
+ #define CDF_LOOP_LIMIT                                 10000
++#define CDF_ELEMENT_LIMIT                              100000
+ 
+ #define CDF_SECID_NULL                                 0
+ #define CDF_SECID_FREE                                 -1
diff --git a/meta/recipes-devtools/file/file_5.37.bb b/meta/recipes-devtools/file/file_5.37.bb
index c53a120b84..71801f9d47 100644
--- a/meta/recipes-devtools/file/file_5.37.bb
+++ b/meta/recipes-devtools/file/file_5.37.bb
@@ -14,7 +14,8 @@ DEPENDS_class-native = "zlib-native"
 # Blacklist a bogus tag in upstream check
 UPSTREAM_CHECK_GITTAGREGEX = "FILE(?P<pver>(?!6_23).+)"
 
-SRC_URI = "git://github.com/file/file.git"
+SRC_URI = "git://github.com/file/file.git \
+           file://CVE-2019-18218.patch"
 
 SRCREV = "a0d5b0e4e9f97d74a9911e95cedd579852e25398"
 S = "${WORKDIR}/git"