check if pointer is != NULL before dereferencing it (Coverity CID 40)

[openssl.git] / crypto / dso / dso_dlfcn.c

diff --git a/crypto/dso/dso_dlfcn.c b/crypto/dso/dso_dlfcn.c
index 56756cf54119fcc7e361838fc90b45e4c6759bd5..979fca80654f850d7bad358fd9fe426971111cc7 100644 (file)
--- a/crypto/dso/dso_dlfcn.c
+++ b/crypto/dso/dso_dlfcn.c
@@ -64,6 +64,7 @@
 # ifndef _GNU_SOURCE
 #  define _GNU_SOURCE  /* make sure dladdr is declared */
 # endif
+# define HAVE_DLINFO 1
 #endif
 
 #include <stdio.h>
@@ -99,6 +100,7 @@ static char *dlfcn_name_converter(DSO *dso, const char *filename);
 static char *dlfcn_merger(DSO *dso, const char *filespec1,
        const char *filespec2);
 static int dlfcn_pathbyaddr(void *addr,char *path,int sz);
+static void *dlfcn_globallookup(const char *name);
 
 static DSO_METHOD dso_meth_dlfcn = {
        "OpenSSL 'dlfcn' shared library method",
@@ -116,7 +118,8 @@ static DSO_METHOD dso_meth_dlfcn = {
        dlfcn_merger,
        NULL, /* init */
        NULL, /* finish */
-       dlfcn_pathbyaddr
+       dlfcn_pathbyaddr,
+       dlfcn_globallookup
        };
 
 DSO_METHOD *DSO_METHOD_dlfcn(void)
@@ -131,6 +134,7 @@ DSO_METHOD *DSO_METHOD_dlfcn(void)
  * be hacked further relatively easily to deal with cases as we find
  * them. Initially this is to cope with OpenBSD. */
 #if defined(__OpenBSD__) || defined(__NetBSD__)
+#      define HAVE_DLINFO 1
 #      ifdef DL_LAZY
 #              define DLOPEN_FLAG DL_LAZY
 #      else
@@ -142,6 +146,7 @@ DSO_METHOD *DSO_METHOD_dlfcn(void)
 #      endif
 #else
 #      ifdef OPENSSL_SYS_SUNOS
+#              define HAVE_DLINFO 1
 #              define DLOPEN_FLAG 1
 #      else
 #              define DLOPEN_FLAG RTLD_NOW /* Hope this works everywhere else */
@@ -291,13 +296,12 @@ static char *dlfcn_merger(DSO *dso, const char *filespec1,
                }
        /* If the first file specification is a rooted path, it rules.
           same goes if the second file specification is missing. */
-       if (!filespec2 || filespec1[0] == '/')
+       if (!filespec2 || (filespec1 != NULL && filespec1[0] == '/'))
                {
                merged = OPENSSL_malloc(strlen(filespec1) + 1);
                if(!merged)
                        {
-                       DSOerr(DSO_F_DLFCN_MERGER,
-                               ERR_R_MALLOC_FAILURE);
+                       DSOerr(DSO_F_DLFCN_MERGER, ERR_R_MALLOC_FAILURE);
                        return(NULL);
                        }
                strcpy(merged, filespec1);
@@ -323,7 +327,7 @@ static char *dlfcn_merger(DSO *dso, const char *filespec1,
                {
                int spec2len, len;
 
-               spec2len = (filespec2 ? strlen(filespec2) : 0);
+               spec2len = strlen(filespec2);
                len = spec2len + (filespec1 ? strlen(filespec1) : 0);
 
                if(filespec2 && filespec2[spec2len - 1] == '/')
@@ -380,7 +384,7 @@ static char *dlfcn_name_converter(DSO *dso, const char *filename)
        }
 
 #ifdef __sgi
-#if 0
+/*
 This is a quote from IRIX manual for dladdr(3c):
 
      <dlfcn.h> does not contain a prototype for dladdr or definition of
@@ -392,7 +396,8 @@ This is a quote from IRIX manual for dladdr(3c):
      part of the IRIX compatibility guarantee; however, there is no future
      intention to change this interface, so on a practical level, the code
      below is safe to use on IRIX.
-#endif
+*/
+#define HAVE_DLINFO 1
 #include <rld_interface.h>
 #ifndef _RLD_INTERFACE_DLFCN_H_DLADDR
 #define _RLD_INTERFACE_DLFCN_H_DLADDR
@@ -416,14 +421,20 @@ static int dladdr(void *address, Dl_info *dl)
        v = _rld_new_interface(_RLD_DLADDR,address,dl);
        return (int)v;
 }
-#endif
+#endif /* __sgi */
 
 static int dlfcn_pathbyaddr(void *addr,char *path,int sz)
        {
+#ifdef HAVE_DLINFO
        Dl_info dli;
        int len;
 
-       if (addr == NULL) addr = dlfcn_pathbyaddr;
+       if (addr == NULL)
+               {
+               union   { int(*f)(void*,char*,int); void *p; } t =
+                       { dlfcn_pathbyaddr };
+               addr = t.p;
+               }
 
        if (dladdr(addr,&dli))
                {
@@ -436,6 +447,20 @@ static int dlfcn_pathbyaddr(void *addr,char *path,int sz)
                }
 
        ERR_add_error_data(4, "dlfcn_pathbyaddr(): ", dlerror());
+#endif
        return -1;
        }
+
+static void *dlfcn_globallookup(const char *name)
+       {
+       void *ret = NULL,*handle = dlopen(NULL,RTLD_LAZY);
+       
+       if (handle)
+               {
+               ret = dlsym(handle,name);
+               dlclose(handle);
+               }
+
+       return ret;
+       }
 #endif /* DSO_DLFCN */