util: fix bad memory access

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

diff --git a/src/shared/util.c b/src/shared/util.c
index a87828d4513fae6c6b9fc0778e84cc5f07fe0a23..8e1409671f258cc31968eb7ae42a382d9dce5fb6 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -439,7 +439,6 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
 
         if (!fgets(line, sizeof(line), f)) {
                 r = feof(f) ? -EIO : -errno;
-                fclose(f);
                 return r;
         }
 
@@ -905,13 +904,10 @@ int get_process_comm(pid_t pid, char **name) {
 }
 
 int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char **line) {
-        char *r, *k;
+        char *r = NULL, *k;
         int c;
-        bool space = false;
-        size_t left;
         FILE *f;
 
-        assert(max_length > 0);
         assert(line);
 
         if (pid == 0)
@@ -927,47 +923,64 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char *
 
         if (!f)
                 return -errno;
+        if (max_length == 0) {
+                size_t len = 1;
+                while ((c = getc(f)) != EOF) {
+                        k = realloc(r, len+1);
+                        if (k == NULL) {
+                                free(r);
+                                fclose(f);
+                                return -ENOMEM;
+                        }
+                        r = k;
+                        r[len-1] = isprint(c) ? c : ' ';
+                        r[len] = 0;
+                        len++;
+                }
+        } else {
+                bool space = false;
+                size_t left;
+                r = new(char, max_length);
+                if (!r) {
+                        fclose(f);
+                        return -ENOMEM;
+                }
 
-        r = new(char, max_length);
-        if (!r) {
-                fclose(f);
-                return -ENOMEM;
-        }
+                k = r;
+                left = max_length;
+                while ((c = getc(f)) != EOF) {
+
+                        if (isprint(c)) {
+                                if (space) {
+                                        if (left <= 4)
+                                                break;
 
-        k = r;
-        left = max_length;
-        while ((c = getc(f)) != EOF) {
+                                        *(k++) = ' ';
+                                        left--;
+                                        space = false;
+                                }
 
-                if (isprint(c)) {
-                        if (space) {
                                 if (left <= 4)
                                         break;
 
-                                *(k++) = ' ';
+                                *(k++) = (char) c;
                                 left--;
-                                space = false;
-                        }
-
-                        if (left <= 4)
-                                break;
+                        }  else
+                                space = true;
+                }
 
-                        *(k++) = (char) c;
-                        left--;
-                }  else
-                        space = true;
+                if (left <= 4) {
+                        size_t n = MIN(left-1, 3U);
+                        memcpy(k, "...", n);
+                        k[n] = 0;
+                } else
+                        *k = 0;
         }
 
-        if (left <= 4) {
-                size_t n = MIN(left-1, 3U);
-                memcpy(k, "...", n);
-                k[n] = 0;
-        } else
-                *k = 0;
-
         fclose(f);
 
         /* Kernel threads have no argv[] */
-        if (r[0] == 0) {
+        if (r == NULL || r[0] == 0) {
                 char *t;
                 int h;