dyld-45.3.tar.gz

diff --git a/src/dyld.cpp b/src/dyld.cpp
index 718bd333be3424c66694f08f9318ff938edaaf90..2f1be413958f4ccffd0a77634772893a699b17b2 100644 (file)
--- a/src/dyld.cpp
+++ b/src/dyld.cpp
@@ -397,37 +397,6 @@ static const char** parseColonList(const char* list)
        return (const char**)result;
 }
 
-/*
- * Library path searching is not done for setuid programs
- * which are not run by the real user.  Futher the
- * evironment varaible for the library path is cleared so
- * that if this program executes a non-set uid program this
- * part of the evironment will not be passed along so that
- * that program also will not have it's libraries searched
- * for.
- */
- static bool riskyUser()
- {
-       static bool checked = false;
-       static bool risky = false;
-       if ( !checked ) {
-               risky = ( getuid() != 0 && (getuid() != geteuid() || getgid() != getegid()) );
-               checked = true;
-       }
-       return risky;
- }
- 
- 
-static bool disableIfBadUser(char* rhs)
-{
-       bool didDisable = false;
-       if ( riskyUser() ) {
-               *rhs ='\0';
-               didDisable = true;
-       }
-       return didDisable;
-}
-
 static void paths_expand_roots(const char **paths, const char *key, const char *val)
 {
 //     assert(val != NULL);
@@ -492,42 +461,34 @@ static void printEnvironmentVariables(const char* envp[])
 void processDyldEnvironmentVarible(const char* key, const char* value)
 {
        if ( strcmp(key, "DYLD_FRAMEWORK_PATH") == 0 ) {
-               if ( !disableIfBadUser((char*)value) )
-                       sEnv.DYLD_FRAMEWORK_PATH = parseColonList(value);
+               sEnv.DYLD_FRAMEWORK_PATH = parseColonList(value);
        }
        else if ( strcmp(key, "DYLD_FALLBACK_FRAMEWORK_PATH") == 0 ) {
-               if ( !disableIfBadUser((char*)value) )
-                       sEnv.DYLD_FALLBACK_FRAMEWORK_PATH = parseColonList(value);
+               sEnv.DYLD_FALLBACK_FRAMEWORK_PATH = parseColonList(value);
        }
        else if ( strcmp(key, "DYLD_LIBRARY_PATH") == 0 ) {
-               if ( !disableIfBadUser((char*)value) )
-                       sEnv.DYLD_LIBRARY_PATH = parseColonList(value);
+               sEnv.DYLD_LIBRARY_PATH = parseColonList(value);
        }
        else if ( strcmp(key, "DYLD_FALLBACK_LIBRARY_PATH") == 0 ) {
-               if ( !disableIfBadUser((char*)value) )
-                       sEnv.DYLD_FALLBACK_LIBRARY_PATH = parseColonList(value);
+               sEnv.DYLD_FALLBACK_LIBRARY_PATH = parseColonList(value);
        }
        else if ( (strcmp(key, "DYLD_ROOT_PATH") == 0) || (strcmp(key, "DYLD_PATHS_ROOT") == 0) ) {
-               if ( !disableIfBadUser((char*)value) ) {
-                       if ( strcmp(value, "/") != 0 ) {
-                               sEnv.DYLD_ROOT_PATH = parseColonList(value);
-                               for (int i=0; sEnv.DYLD_ROOT_PATH[i] != NULL; ++i) {
-                                       if ( sEnv.DYLD_ROOT_PATH[i][0] != '/' ) {
-                                               fprintf(stderr, "dyld: warning DYLD_ROOT_PATH not used because it contains a non-absolute path\n");
-                                               sEnv.DYLD_ROOT_PATH = NULL;
-                                               break;
-                                       }
+               if ( strcmp(value, "/") != 0 ) {
+                       sEnv.DYLD_ROOT_PATH = parseColonList(value);
+                       for (int i=0; sEnv.DYLD_ROOT_PATH[i] != NULL; ++i) {
+                               if ( sEnv.DYLD_ROOT_PATH[i][0] != '/' ) {
+                                       fprintf(stderr, "dyld: warning DYLD_ROOT_PATH not used because it contains a non-absolute path\n");
+                                       sEnv.DYLD_ROOT_PATH = NULL;
+                                       break;
                                }
                        }
                }
        } 
        else if ( strcmp(key, "DYLD_IMAGE_SUFFIX") == 0 ) {
-               if ( !disableIfBadUser((char*)value) )
-                       gLinkContext.imageSuffix = value;
+               gLinkContext.imageSuffix = value;
        }
        else if ( strcmp(key, "DYLD_INSERT_LIBRARIES") == 0 ) {
-               if ( !disableIfBadUser((char*)value) )
-                       sEnv.DYLD_INSERT_LIBRARIES = parseColonList(value);
+               sEnv.DYLD_INSERT_LIBRARIES = parseColonList(value);
        }
        else if ( strcmp(key, "DYLD_DEBUG_TRACE") == 0 ) {
                fprintf(stderr, "dyld: warning DYLD_DEBUG_TRACE not supported\n");
@@ -653,6 +614,48 @@ void processDyldEnvironmentVarible(const char* key, const char* value)
        }
 }
 
+//
+// For security, setuid programs ignore DYLD_* environment variables.
+// Additionally, the DYLD_* enviroment variables are removed
+// from the environment, so that any child processes don't see them.
+//
+static void pruneEnvironmentVariables(const char* envp[], const char*** applep)
+{
+       // delete all DYLD_* and LD_LIBRARY_PATH environment variables
+       int removedCount = 0;
+       const char** d = envp;
+       for(const char** s = envp; *s != NULL; s++) {
+           if ( (strncmp(*s, "DYLD_", 5) != 0) && (strncmp(*s, "LD_LIBRARY_PATH=", 16) != 0) ) {
+                       *d++ = *s;
+               }
+               else {
+                       ++removedCount;
+               }
+       }
+       *d++ = NULL;
+       
+       // slide apple parameters
+       if ( removedCount > 0 ) {
+               *applep = d;
+               do {
+                       *d = d[removedCount];
+               } while ( *d++ != NULL );
+       }
+       
+       // setup DYLD_FALLBACK_FRAMEWORK_PATH, if not set in environment
+       if ( sEnv.DYLD_FALLBACK_FRAMEWORK_PATH == NULL ) {
+               const char** paths = sFrameworkFallbackPaths;
+               removePathWithPrefix(paths, "$HOME");
+               sEnv.DYLD_FALLBACK_FRAMEWORK_PATH = paths;
+       }
+
+       // default value for DYLD_FALLBACK_LIBRARY_PATH, if not set in environment
+       if ( sEnv.DYLD_FALLBACK_LIBRARY_PATH == NULL ) {
+               const char** paths = sLibraryFallbackPaths;
+               removePathWithPrefix(paths, "$HOME");
+               sEnv.DYLD_FALLBACK_LIBRARY_PATH = paths;
+       }
+}
 
 static void checkEnvironmentVariables(const char* envp[], bool ignoreEnviron)
 {
@@ -676,8 +679,7 @@ static void checkEnvironmentVariables(const char* envp[], bool ignoreEnviron)
                }
                else if ( strncmp(keyEqualsValue, "LD_LIBRARY_PATH=", 16) == 0 ) {
                        const char* path = &keyEqualsValue[16];
-                       if ( !disableIfBadUser((char*)path) )
-                               sEnv.LD_LIBRARY_PATH = parseColonList(path);
+                       sEnv.LD_LIBRARY_PATH = parseColonList(path);
                }
        }
                
@@ -2001,7 +2003,10 @@ _main(const struct mach_header* mainExecutableMH, int argc, const char* argv[],
        }
        uintptr_t result = 0;
        sMainExecutableMachHeader = mainExecutableMH;
-       checkEnvironmentVariables(envp, isEmulated);
+       if ( issetugid() )
+               pruneEnvironmentVariables(envp, &apple);
+       else
+               checkEnvironmentVariables(envp, isEmulated);
        if ( sEnv.DYLD_PRINT_OPTS ) 
                printOptions(argv);
        if ( sEnv.DYLD_PRINT_ENV ) 

diff --git a/unit-tests/test-cases/suid-environ/main.c b/unit-tests/test-cases/suid-environ/main.c
index c0410e193a1ecb9937cdb85344cad9376588c8d9..43a9749fac193e97559e2b4931ae8294a856d15c 100644 (file)
--- a/unit-tests/test-cases/suid-environ/main.c
+++ b/unit-tests/test-cases/suid-environ/main.c
@@ -30,15 +30,34 @@
 // binaries set to run as some other user id never see any DYLD_ environment variables
 //
 
-int main(int argc, const char* argv[], const char* envp[])
+int main(int argc, const char* argv[], const char* envp[], const char* apple[])
 {
-       for(const char** p = envp; *p != NULL; p++) {
+       // verify no DYLD_ variables
+       const char** p;
+       for(p = envp; *p != NULL; p++) {
                //fprintf(stderr, "%s\n", *p);
                if ( strncmp(*p, "DYLD_", 5) == 0 ) {
                        FAIL("suid-environ: found %s", *p);
                        return EXIT_SUCCESS;
                }
        }
+       // verify same as apple parameter
+       ++p;
+       if ( apple != p ) {
+               FAIL("suid-environ: apple parameter not at end of envp");
+               return EXIT_SUCCESS;
+       }
+       
+       // verify apple parameter is not NULL and ends in main
+       if ( *apple == NULL ) {
+               FAIL("suid-environ: apple parameter is empty");
+               return EXIT_SUCCESS;
+       }
+       if ( strstr(*apple, "/main") == NULL ) {
+               FAIL("suid-environ: apple parameter is not path to main");
+               return EXIT_SUCCESS;
+       }
+       
        PASS("suid-environ");
        return EXIT_SUCCESS;
 }