CryptoPkg/Crt: turn strchr() into a function (CVE-2019-14553)

According to the ISO C standard, strchr() is a function. We #define it as
a macro. Unfortunately, our macro evaluates the first argument ("str")
twice. If the expression passed for "str" has side effects, the behavior
may be undefined.

In a later patch in this series, we're going to resurrect "inet_pton.c"
(originally from the StdLib package), which calls strchr() just like that:

  strchr((xdigits = xdigits_l), ch)
  strchr((xdigits = xdigits_u), ch)

To enable this kind of function call, turn strchr() into a function.

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Sivaraman Nainar <sivaramann@amiindia.co.in>
Cc: Xiaoyu Lu <xiaoyux.lu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=960
CVE: CVE-2019-14553
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Jiaxin Wu <jiaxin.wu@intel.com>

diff --git a/CryptoPkg/Library/BaseCryptLib/SysCall/CrtWrapper.c b/CryptoPkg/Library/BaseCryptLib/SysCall/CrtWrapper.c
index 71a2ef34ed2bd99dc986c082199546e6a6516906..42235ab96ac3e6e4fab85dac1d8fba43829e366a 100644 (file)
--- a/CryptoPkg/Library/BaseCryptLib/SysCall/CrtWrapper.c
+++ b/CryptoPkg/Library/BaseCryptLib/SysCall/CrtWrapper.c
@@ -115,6 +115,11 @@ QuickSortWorker (
 // -- String Manipulation Routines --\r
 //\r
 \r
+char *strchr(const char *str, int ch)\r
+{\r
+  return ScanMem8 (str, AsciiStrSize (str), (UINT8)ch);\r
+}\r
+\r
 /* Scan a string for the last occurrence of a character */\r
 char *strrchr (const char *str, int c)\r
 {\r

diff --git a/CryptoPkg/Library/Include/CrtLibSupport.h b/CryptoPkg/Library/Include/CrtLibSupport.h
index 5806f50f7485101dad8bb9da18306aa8747b3928..b90da20ff7e79e4b43b8434fd67df7cf4d6f49be 100644 (file)
--- a/CryptoPkg/Library/Include/CrtLibSupport.h
+++ b/CryptoPkg/Library/Include/CrtLibSupport.h
@@ -147,6 +147,7 @@ int            isupper     (int);
 int            tolower     (int);\r
 int            strcmp      (const char *, const char *);\r
 int            strncasecmp (const char *, const char *, size_t);\r
+char           *strchr     (const char *, int);\r
 char           *strrchr    (const char *, int);\r
 unsigned long  strtoul     (const char *, char **, int);\r
 long           strtol      (const char *, char **, int);\r
@@ -188,7 +189,6 @@ void           abort       (void);
 #define strcpy(strDest,strSource)         AsciiStrCpyS(strDest,MAX_STRING_SIZE,strSource)\r
 #define strncpy(strDest,strSource,count)  AsciiStrnCpyS(strDest,MAX_STRING_SIZE,strSource,(UINTN)count)\r
 #define strcat(strDest,strSource)         AsciiStrCatS(strDest,MAX_STRING_SIZE,strSource)\r
-#define strchr(str,ch)                    ScanMem8((VOID *)(str),AsciiStrSize(str),(UINT8)ch)\r
 #define strncmp(string1,string2,count)    (int)(AsciiStrnCmp(string1,string2,(UINTN)(count)))\r
 #define strcasecmp(str1,str2)             (int)AsciiStriCmp(str1,str2)\r
 #define sprintf(buf,...)                  AsciiSPrint(buf,MAX_STRING_SIZE,__VA_ARGS__)\r