util-lib: get_current_dir_name() can return errors other than ENOMEM

get_current_dir_name() can return a variety of errors, not just ENOMEM,
hence don't blindly turn its errors to ENOMEM, but return correct errors
in path_make_absolute_cwd().

This trickles down into a couple of other functions, some of which
receive unrelated minor fixes too with this commit.

3 files changed, 91 insertions, 69 deletions

diff --git a/src/basic/path-util.c b/src/basic/path-util.c
index 9aeb8c23fd..96705cc9d8 100644
--- a/src/basic/path-util.c
+++ b/src/basic/path-util.c
@@ -84,20 +84,25 @@ int path_get_parent(const char *path, char **_r) {
         return 0;
 }
 
-char **path_split_and_make_absolute(const char *p) {
+int path_split_and_make_absolute(const char *p, char ***ret) {
         char **l;
+        int r;
+
         assert(p);
+        assert(ret);
 
         l = strv_split(p, ":");
         if (!l)
                 return NULL;
 
-        if (!path_strv_make_absolute_cwd(l)) {
+        r = path_strv_make_absolute_cwd(l);
+        if (r < 0) {
                 strv_free(l);
-                return NULL;
+                return r;
         }
 
-        return l;
+        *ret = l;
+        return r;
 }
 
 char *path_make_absolute(const char *p, const char *prefix) {
@@ -112,22 +117,31 @@ char *path_make_absolute(const char *p, const char *prefix) {
         return strjoin(prefix, "/", p, NULL);
 }
 
-char *path_make_absolute_cwd(const char *p) {
-        _cleanup_free_ char *cwd = NULL;
+int path_make_absolute_cwd(const char *p, char **ret) {
+        char *c;
 
         assert(p);
+        assert(ret);
 
         /* Similar to path_make_absolute(), but prefixes with the
          * current working directory. */
 
         if (path_is_absolute(p))
-                return strdup(p);
+                c = strdup(p);
+        else {
+                _cleanup_free_ char *cwd = NULL;
 
-        cwd = get_current_dir_name();
-        if (!cwd)
-                return NULL;
+                cwd = get_current_dir_name();
+                if (!cwd)
+                        return -errno;
+
+                c = strjoin(cwd, "/", p, NULL);
+        }
+        if (!c)
+                return -ENOMEM;
 
-        return strjoin(cwd, "/", p, NULL);
+        *ret = c;
+        return 0;
 }
 
 int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
@@ -215,8 +229,9 @@ int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
         return 0;
 }
 
-char **path_strv_make_absolute_cwd(char **l) {
+int path_strv_make_absolute_cwd(char **l) {
         char **s;
+        int r;
 
         /* Goes through every item in the string list and makes it
          * absolute. This works in place and won't rollback any
@@ -225,15 +240,15 @@ char **path_strv_make_absolute_cwd(char **l) {
         STRV_FOREACH(s, l) {
                 char *t;
 
-                t = path_make_absolute_cwd(*s);
-                if (!t)
-                        return NULL;
+                r = path_make_absolute_cwd(*s, &t);
+                if (r < 0)
+                        return r;
 
                 free(*s);
                 *s = t;
         }
 
-        return l;
+        return 0;
 }
 
 char **path_strv_resolve(char **l, const char *prefix) {
@@ -719,13 +734,9 @@ int find_binary(const char *name, char **ret) {
                         return -errno;
 
                 if (ret) {
-                        char *rs;
-
-                        rs = path_make_absolute_cwd(name);
-                        if (!rs)
-                                return -ENOMEM;
-
-                        *ret = rs;
+                        r = path_make_absolute_cwd(name, ret);
+                        if (r < 0)
+                                return r;
                 }
 
                 return 0;
@@ -750,6 +761,9 @@ int find_binary(const char *name, char **ret) {
                 if (r == 0)
                         break;
 
+                if (!path_is_absolute(element))
+                        continue;
+
                 j = strjoin(element, "/", name, NULL);
                 if (!j)
                         return -ENOMEM;
diff --git a/src/basic/path-util.h b/src/basic/path-util.h
index 03e1ac5d60..c37c131bff 100644
--- a/src/basic/path-util.h
+++ b/src/basic/path-util.h
@@ -36,11 +36,11 @@
 #endif
 
 bool is_path(const char *p) _pure_;
-char** path_split_and_make_absolute(const char *p);
+int path_split_and_make_absolute(const char *p, char ***ret);
 int path_get_parent(const char *path, char **parent);
 bool path_is_absolute(const char *p) _pure_;
 char* path_make_absolute(const char *p, const char *prefix);
-char* path_make_absolute_cwd(const char *p);
+int path_make_absolute_cwd(const char *p, char **ret);
 int path_make_relative(const char *from_dir, const char *to_path, char **_r);
 char* path_kill_slashes(char *path);
 char* path_startswith(const char *path, const char *prefix) _pure_;
@@ -49,7 +49,7 @@ bool path_equal(const char *a, const char *b) _pure_;
 bool path_equal_or_files_same(const char *a, const char *b);
 char* path_join(const char *root, const char *path, const char *rest);
 
-char** path_strv_make_absolute_cwd(char **l);
+int path_strv_make_absolute_cwd(char **l);
 char** path_strv_resolve(char **l, const char *prefix);
 char** path_strv_resolve_uniq(char **l, const char *prefix);
 
diff --git a/src/basic/selinux-util.c b/src/basic/selinux-util.c
index 747e6f4dbb..7a7dc90e3c 100644
--- a/src/basic/selinux-util.c
+++ b/src/basic/selinux-util.c
@@ -171,15 +171,15 @@ int mac_selinux_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
 int mac_selinux_apply(const char *path, const char *label) {
 
 #ifdef HAVE_SELINUX
-        assert(path);
-        assert(label);
-
         if (!mac_selinux_use())
                 return 0;
 
+        assert(path);
+        assert(label);
+
         if (setfilecon(path, (security_context_t) label) < 0) {
                 log_enforcing("Failed to set SELinux security context %s on path %s: %m", label, path);
-                if (security_getenforce() == 1)
+                if (security_getenforce() > 0)
                         return -errno;
         }
 #endif
@@ -312,10 +312,10 @@ char* mac_selinux_free(char *label) {
 }
 
 int mac_selinux_create_file_prepare(const char *path, mode_t mode) {
-        int r = 0;
 
 #ifdef HAVE_SELINUX
         _cleanup_security_context_free_ security_context_t filecon = NULL;
+        int r;
 
         assert(path);
 
@@ -325,34 +325,33 @@ int mac_selinux_create_file_prepare(const char *path, mode_t mode) {
         if (path_is_absolute(path))
                 r = selabel_lookup_raw(label_hnd, &filecon, path, mode);
         else {
-                _cleanup_free_ char *newpath;
+                _cleanup_free_ char *newpath = NULL;
 
-                newpath = path_make_absolute_cwd(path);
-                if (!newpath)
-                        return -ENOMEM;
+                r = path_make_absolute_cwd(path, &newpath);
+                if (r < 0)
+                        return r;
 
                 r = selabel_lookup_raw(label_hnd, &filecon, newpath, mode);
         }
 
-        /* No context specified by the policy? Proceed without setting it. */
-        if (r < 0 && errno == ENOENT)
-                return 0;
+        if (r < 0) {
+                /* No context specified by the policy? Proceed without setting it. */
+                if (errno == ENOENT)
+                        return 0;
 
-        if (r < 0)
-                r = -errno;
-        else {
-                r = setfscreatecon(filecon);
-                if (r < 0) {
-                        log_enforcing("Failed to set SELinux security context %s for %s: %m", filecon, path);
-                        r = -errno;
-                }
+                log_enforcing("Failed to determine SELinux security context for %s: %m", path);
+        } else {
+                if (setfscreatecon(filecon) >= 0)
+                        return 0; /* Success! */
+
+                log_enforcing("Failed to set SELinux security context %s for %s: %m", filecon, path);
         }
 
-        if (r < 0 && security_getenforce() == 0)
-                r = 0;
-#endif
+        if (security_getenforce() > 0)
+                return -errno;
 
-        return r;
+#endif
+        return 0;
 }
 
 void mac_selinux_create_file_clear(void) {
@@ -405,6 +404,7 @@ int mac_selinux_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
 #ifdef HAVE_SELINUX
         _cleanup_security_context_free_ security_context_t fcon = NULL;
         const struct sockaddr_un *un;
+        bool context_changed = false;
         char *path;
         int r;
 
@@ -420,7 +420,7 @@ int mac_selinux_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
                 goto skipped;
 
         /* Filter out anonymous sockets */
-        if (addrlen < sizeof(sa_family_t) + 1)
+        if (addrlen < offsetof(struct sockaddr_un, sun_path) + 1)
                 goto skipped;
 
         /* Filter out abstract namespace sockets */
@@ -433,36 +433,44 @@ int mac_selinux_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
         if (path_is_absolute(path))
                 r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFSOCK);
         else {
-                _cleanup_free_ char *newpath;
+                _cleanup_free_ char *newpath = NULL;
 
-                newpath = path_make_absolute_cwd(path);
-                if (!newpath)
-                        return -ENOMEM;
+                r = path_make_absolute_cwd(path, &newpath);
+                if (r < 0)
+                        return r;
 
                 r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFSOCK);
         }
 
-        if (r == 0)
-                r = setfscreatecon(fcon);
+        if (r < 0) {
+                /* No context specified by the policy? Proceed without setting it */
+                if (errno == ENOENT)
+                        goto skipped;
 
-        if (r < 0 && errno != ENOENT) {
-                log_enforcing("Failed to set SELinux security context %s for %s: %m", fcon, path);
+                log_enforcing("Failed to determine SELinux security context for %s: %m", path);
+                if (security_getenforce() > 0)
+                        return -errno;
 
-                if (security_getenforce() == 1) {
-                        r = -errno;
-                        goto finish;
-                }
+        } else {
+                if (setfscreatecon(fcon) < 0) {
+                        log_enforcing("Failed to set SELinux security context %s for %s: %m", fcon, path);
+                        if (security_getenforce() > 0)
+                                return -errno;
+                } else
+                        context_changed = true;
         }
 
-        r = bind(fd, addr, addrlen);
-        if (r < 0)
-                r = -errno;
+        r = bind(fd, addr, addrlen) < 0 ? -errno : 0;
+
+        if (context_changed)
+                setfscreatecon(NULL);
 
-finish:
-        setfscreatecon(NULL);
         return r;
 
 skipped:
 #endif
-        return bind(fd, addr, addrlen) < 0 ? -errno : 0;
+        if (bind(fd, addr, addrlen) < 0)
+                return -errno;
+
+        return 0;
 }