import-layers/yocto-poky/meta/recipes-support/libpcre/libpcre2/libpcre2-CVE-2017-7186.patch

libpcre2-10.23: Fix CVE-2017-7186

A fuzz on libpcre1 through the pcretest utility revealed an invalid read in the
library. For who is interested in a detailed description of the bug, will
follow a feedback from upstream:

This was a genuine bug in the 32-bit library. Thanks for finding it. The crash
was caused by trying to find a Unicode property for a code value greater than
0x10ffff, the Unicode maximum, when running in non-UTF mode (where character
values can be up to 0xffffffff).

The complete ASan output:

# pcretest -32 -d $FILE
==14788==ERROR: AddressSanitizer: SEGV on unknown address 0x7f1bbffed4df (pc 0x7f1bbee3fe6b bp 0x7fff8b50d8c0 sp 0x7fff8b50d3a0 T0)
==14788==The signal is caused by a READ memory access.
    #0 0x7f1bbee3fe6a in match /tmp/portage/dev-libs/libpcre-8.40/work/pcre-8.40/pcre_exec.c:5473:18
    #1 0x7f1bbee09226 in pcre32_exec /tmp/portage/dev-libs/libpcre-8.40/work/pcre-8.40/pcre_exec.c:6936:8
    #2 0x527d6c in main /tmp/portage/dev-libs/libpcre-8.40/work/pcre-8.40/pcretest.c:5218:9
    #3 0x7f1bbddd678f in __libc_start_main /tmp/portage/sys-libs/glibc-2.23-r3/work/glibc-2.23/csu/../csu/libc-start.c:289
    #4 0x41b438 in _init (/usr/bin/pcretest+0x41b438)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV /tmp/portage/dev-libs/libpcre-8.40/work/pcre-8.40/pcre_exec.c:5473:18 in match
==14788==ABORTING

Upstream-Status: Backport [https://vcs.pcre.org/pcre2/code/trunk/src/pcre2_ucd.c?view=patch&r1=316&r2=670&sortby=date \
                        https://vcs.pcre.org/pcre2/code/trunk/src/pcre2_internal.h?view=patch&r1=600&r2=670&sortby=date]
CVE: CVE-2017-7186

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>

--- trunk/src/pcre2_ucd.c  2015/07/17 15:44:51 316
+++ trunk/src/pcre2_ucd.c  2017/02/24 18:25:32 670
@@ -41,6 +41,20 @@
 
 const char *PRIV(unicode_version) = "8.0.0";
 
+/* If the 32-bit library is run in non-32-bit mode, character values
+greater than 0x10ffff may be encountered. For these we set up a
+special record. */
+
+#if PCRE2_CODE_UNIT_WIDTH == 32
+const ucd_record PRIV(dummy_ucd_record)[] = {{
+  ucp_Common,    /* script */
+  ucp_Cn,        /* type unassigned */
+  ucp_gbOther,   /* grapheme break property */
+  0,             /* case set */
+  0,             /* other case */
+  }};
+#endif
+
 /* When recompiling tables with a new Unicode version, please check the
 types in this structure definition from pcre2_internal.h (the actual
 field names will be different):
--- trunk/src/pcre2_internal.h 2016/11/19 12:46:24 600
+++ trunk/src/pcre2_internal.h 2017/02/24 18:25:32 670
@@ -1774,10 +1774,17 @@
 /* UCD access macros */
 
 #define UCD_BLOCK_SIZE 128
-#define GET_UCD(ch) (PRIV(ucd_records) + \
+#define REAL_GET_UCD(ch) (PRIV(ucd_records) + \
         PRIV(ucd_stage2)[PRIV(ucd_stage1)[(int)(ch) / UCD_BLOCK_SIZE] * \
         UCD_BLOCK_SIZE + (int)(ch) % UCD_BLOCK_SIZE])
 
+#if PCRE2_CODE_UNIT_WIDTH == 32
+#define GET_UCD(ch) ((ch > MAX_UTF_CODE_POINT)? \
+  PRIV(dummy_ucd_record) : REAL_GET_UCD(ch))
+#else
+#define GET_UCD(ch) REAL_GET_UCD(ch)
+#endif
+
 #define UCD_CHARTYPE(ch)    GET_UCD(ch)->chartype
 #define UCD_SCRIPT(ch)      GET_UCD(ch)->script
 #define UCD_CATEGORY(ch)    PRIV(ucp_gentype)[UCD_CHARTYPE(ch)]
@@ -1834,6 +1841,9 @@
 #define _pcre2_default_compile_context PCRE2_SUFFIX(_pcre2_default_compile_context_)
 #define _pcre2_default_match_context   PCRE2_SUFFIX(_pcre2_default_match_context_)
 #define _pcre2_default_tables          PCRE2_SUFFIX(_pcre2_default_tables_)
+#if PCRE2_CODE_UNIT_WIDTH == 32
+#define _pcre2_dummy_ucd_record        PCRE2_SUFFIX(_pcre2_dummy_ucd_record_)
+#endif
 #define _pcre2_hspace_list             PCRE2_SUFFIX(_pcre2_hspace_list_)
 #define _pcre2_vspace_list             PCRE2_SUFFIX(_pcre2_vspace_list_)
 #define _pcre2_ucd_caseless_sets       PCRE2_SUFFIX(_pcre2_ucd_caseless_sets_)
@@ -1858,6 +1868,9 @@
 extern const uint32_t                  PRIV(vspace_list)[];
 extern const uint32_t                  PRIV(ucd_caseless_sets)[];
 extern const ucd_record                PRIV(ucd_records)[];
+#if PCRE2_CODE_UNIT_WIDTH == 32
+extern const ucd_record                PRIV(dummy_ucd_record)[];
+#endif
 extern const uint8_t                   PRIV(ucd_stage1)[];
 extern const uint16_t                  PRIV(ucd_stage2)[];
 extern const uint32_t                  PRIV(ucp_gbtable)[];