util: skip incomplete ucred information in getpeersec()

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index 3eb8a0f44210ff3935f5176eb79c915480ccf106..b1ba0ed857b24090b7e57b733f999e68e38c1a53 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -363,6 +363,46 @@ int safe_atou8(const char *s, uint8_t *ret) {
         return 0;
 }
 
+int safe_atou16(const char *s, uint16_t *ret) {
+        char *x = NULL;
+        unsigned long l;
+
+        assert(s);
+        assert(ret);
+
+        errno = 0;
+        l = strtoul(s, &x, 0);
+
+        if (!x || x == s || *x || errno)
+                return errno > 0 ? -errno : -EINVAL;
+
+        if ((unsigned long) (uint16_t) l != l)
+                return -ERANGE;
+
+        *ret = (uint16_t) l;
+        return 0;
+}
+
+int safe_atoi16(const char *s, int16_t *ret) {
+        char *x = NULL;
+        long l;
+
+        assert(s);
+        assert(ret);
+
+        errno = 0;
+        l = strtol(s, &x, 0);
+
+        if (!x || x == s || *x || errno)
+                return errno > 0 ? -errno : -EINVAL;
+
+        if ((long) (int16_t) l != l)
+                return -ERANGE;
+
+        *ret = (int16_t) l;
+        return 0;
+}
+
 int safe_atollu(const char *s, long long unsigned *ret_llu) {
         char *x = NULL;
         unsigned long long l;
@@ -757,19 +797,30 @@ int get_process_capeff(pid_t pid, char **capeff) {
         return get_status_field(p, "\nCapEff:", capeff);
 }
 
+static int get_process_link_contents(const char *proc_file, char **name) {
+        int r;
+
+        assert(proc_file);
+        assert(name);
+
+        r = readlink_malloc(proc_file, name);
+        if (r < 0)
+                return r == -ENOENT ? -ESRCH : r;
+
+        return 0;
+}
+
 int get_process_exe(pid_t pid, char **name) {
         const char *p;
         char *d;
         int r;
 
         assert(pid >= 0);
-        assert(name);
 
         p = procfs_file_alloca(pid, "exe");
-
-        r = readlink_malloc(p, name);
+        r = get_process_link_contents(p, name);
         if (r < 0)
-                return r == -ENOENT ? -ESRCH : r;
+                return r;
 
         d = endswith(*name, " (deleted)");
         if (d)
@@ -821,6 +872,26 @@ int get_process_gid(pid_t pid, gid_t *gid) {
         return get_process_id(pid, "Gid:", gid);
 }
 
+int get_process_cwd(pid_t pid, char **cwd) {
+        const char *p;
+
+        assert(pid >= 0);
+
+        p = procfs_file_alloca(pid, "cwd");
+
+        return get_process_link_contents(p, cwd);
+}
+
+int get_process_root(pid_t pid, char **root) {
+        const char *p;
+
+        assert(pid >= 0);
+
+        p = procfs_file_alloca(pid, "root");
+
+        return get_process_link_contents(p, root);
+}
+
 char *strnappend(const char *s, const char *suffix, size_t b) {
         size_t a;
         char *r;
@@ -893,6 +964,28 @@ int readlink_malloc(const char *p, char **ret) {
         return readlinkat_malloc(AT_FDCWD, p, ret);
 }
 
+int readlink_value(const char *p, char **ret) {
+        _cleanup_free_ char *link = NULL;
+        char *value;
+        int r;
+
+        r = readlink_malloc(p, &link);
+        if (r < 0)
+                return r;
+
+        value = basename(link);
+        if (!value)
+                return -ENOENT;
+
+        value = strdup(value);
+        if (!value)
+                return -ENOMEM;
+
+        *ret = value;
+
+        return 0;
+}
+
 int readlink_and_make_absolute(const char *p, char **r) {
         _cleanup_free_ char *target = NULL;
         char *k;
@@ -2783,7 +2876,7 @@ int get_ctty(pid_t pid, dev_t *_devnr, char **r) {
         if (k < 0)
                 return k;
 
-        snprintf(fn, sizeof(fn), "/dev/char/%u:%u", major(devnr), minor(devnr));
+        sprintf(fn, "/dev/char/%u:%u", major(devnr), minor(devnr));
 
         k = readlink_malloc(fn, &s);
         if (k < 0) {
@@ -3270,7 +3363,7 @@ char **replace_env_argv(char **argv, char **env) {
                         if (e) {
                                 int r;
 
-                                r = strv_split_quoted(&m, e);
+                                r = strv_split_quoted(&m, e, true);
                                 if (r < 0) {
                                         ret[k] = NULL;
                                         strv_free(ret);
@@ -3591,41 +3684,33 @@ char *unquote(const char *s, const char* quotes) {
 }
 
 char *normalize_env_assignment(const char *s) {
-        _cleanup_free_ char *name = NULL, *value = NULL, *p = NULL;
-        char *eq, *r;
+        _cleanup_free_ char *value = NULL;
+        const char *eq;
+        char *p, *name;
 
         eq = strchr(s, '=');
         if (!eq) {
-                char *t;
+                char *r, *t;
 
                 r = strdup(s);
                 if (!r)
                         return NULL;
 
                 t = strstrip(r);
-                if (t == r)
-                        return r;
+                if (t != r)
+                        memmove(r, t, strlen(t) + 1);
 
-                memmove(r, t, strlen(t) + 1);
                 return r;
         }
 
-        name = strndup(s, eq - s);
-        if (!name)
-                return NULL;
-
-        p = strdup(eq + 1);
-        if (!p)
-                return NULL;
+        name = strndupa(s, eq - s);
+        p = strdupa(eq + 1);
 
         value = unquote(strstrip(p), QUOTES);
         if (!value)
                 return NULL;
 
-        if (asprintf(&r, "%s=%s", strstrip(name), value) < 0)
-                r = NULL;
-
-        return r;
+        return strjoin(strstrip(name), "=", value, NULL);
 }
 
 int wait_for_terminate(pid_t pid, siginfo_t *status) {
@@ -6397,6 +6482,10 @@ int getpeercred(int fd, struct ucred *ucred) {
          * to namespacing issues */
         if (u.pid <= 0)
                 return -ENODATA;
+        if (u.uid == (uid_t) -1)
+                return -ENODATA;
+        if (u.gid == (gid_t) -1)
+                return -ENODATA;
 
         *ucred = u;
         return 0;