commit 1f73f10460f7cbccc898dcdd6dc949c08132bbf2
author Suren Baghdasaryan <surenb@google.com> Fri Oct 04 16:06:55 2019 -0700
committer Suren Baghdasaryan <surenb@google.com> Mon Oct 07 12:50:38 2019 -0700
tree 9e31e54d89bba11c0f964ecd168eb1d4d30526f7
parent 2d6d7fe470d3bd54e85587a335769721f76e3e35

lmkd: Fix string null termination in proc_get_size and proc_get_name

Fix string null termination and cleanup proc_get_size and proc_get_name
functions.

Bug: 74119935
Test: lmkd_unit_test
Change-Id: Ied176b8d347b672b91866ac59a813d4ff349930a
Signed-off-by: Suren Baghdasaryan <surenb@google.com>

lmkd/lmkd.c

diff --git a/lmkd/lmkd.c b/lmkd/lmkd.c
index 372e10f..18cd9f5 100644
--- a/lmkd/lmkd.c
+++ b/lmkd/lmkd.c
@@ -782,15 +782,15 @@
         close(fd);
         return -1;
     }
+    line[ret] = '\0';
 
     sscanf(line, "%d %d ", &total, &rss);
     close(fd);
     return rss;
 }
 
-static char *proc_get_name(int pid) {
+static char *proc_get_name(int pid, char *buf, size_t buf_size) {
     char path[PATH_MAX];
-    static char line[LINE_MAX];
     int fd;
     char *cp;
     ssize_t ret;
@@ -801,25 +801,24 @@
     if (fd == -1) {
         return NULL;
     }
-    ret = read_all(fd, line, sizeof(line) - 1);
+    ret = read_all(fd, buf, buf_size - 1);
     close(fd);
     if (ret < 0) {
         return NULL;
     }
+    buf[ret] = '\0';
 
-    cp = strchr(line, ' ');
+    cp = strchr(buf, ' ');
     if (cp) {
         *cp = '\0';
-    } else {
-        line[ret] = '\0';
     }
 
-    return line;
+    return buf;
 }
 
 static void cmd_procprio(LMKD_CTRL_PACKET packet) {
     struct proc *procp;
-    char path[80];
+    char path[LINE_MAX];
     char val[20];
     int soft_limit_mult;
     struct lmk_procprio params;
@@ -856,7 +855,8 @@
     }
 
     if (use_inkernel_interface) {
-        stats_store_taskname(params.pid, proc_get_name(params.pid), kpoll_info.poll_fd);
+        stats_store_taskname(params.pid, proc_get_name(params.pid, path, sizeof(path)),
+                             kpoll_info.poll_fd);
         return;
     }
 
@@ -1660,6 +1660,7 @@
     int r;
     int result = -1;
     struct memory_stat *mem_st;
+    char buf[LINE_MAX];
 
     tgid = proc_get_tgid(pid);
     if (tgid >= 0 && tgid != pid) {
@@ -1667,7 +1668,7 @@
         goto out;
     }
 
-    taskname = proc_get_name(pid);
+    taskname = proc_get_name(pid, buf, sizeof(buf));
     if (!taskname) {
         goto out;
     }