Fix: handle sysconf errors

[lttng-ust.git] / liblttng-ust / lttng-ust-comm.c

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index a6e4ba35c9a68f9dae607d196f6c640f751c2989..f9d957d86e67c4f4b684df801e7f05aead111eb4 100644 (file)
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -677,9 +677,14 @@ void cleanup_sock_info(struct sock_info *sock_info, int exiting)
                sock_info->notify_socket = -1;
        }
        if (sock_info->wait_shm_mmap) {
-               ret = munmap(sock_info->wait_shm_mmap, sysconf(_SC_PAGE_SIZE));
-               if (ret) {
-                       ERR("Error unmapping wait shm");
+               long page_size;
+
+               page_size = sysconf(_SC_PAGE_SIZE);
+               if (page_size > 0) {
+                       ret = munmap(sock_info->wait_shm_mmap, page_size);
+                       if (ret) {
+                               ERR("Error unmapping wait shm");
+                       }
                }
                sock_info->wait_shm_mmap = NULL;
        }
@@ -852,15 +857,20 @@ error_close:
 static
 char *get_map_shm(struct sock_info *sock_info)
 {
-       size_t mmap_size = sysconf(_SC_PAGE_SIZE);
+       long page_size;
        int wait_shm_fd, ret;
        char *wait_shm_mmap;
 
-       wait_shm_fd = get_wait_shm(sock_info, mmap_size);
+       page_size = sysconf(_SC_PAGE_SIZE);
+       if (page_size < 0) {
+               goto error;
+       }
+
+       wait_shm_fd = get_wait_shm(sock_info, page_size);
        if (wait_shm_fd < 0) {
                goto error;
        }
-       wait_shm_mmap = mmap(NULL, mmap_size, PROT_READ,
+       wait_shm_mmap = mmap(NULL, page_size, PROT_READ,
                  MAP_SHARED, wait_shm_fd, 0);
        /* close shm fd immediately after taking the mmap reference */
        ret = close(wait_shm_fd);