@@ -59,6 +59,7 @@ int ring_buffer__add(struct ring_buffer *rb, int map_fd,
__u32 len = sizeof(info);
struct epoll_event *e;
struct ring *r;
+ __u64 mmap_sz;
void *tmp;
int err;
@@ -97,8 +98,7 @@ int ring_buffer__add(struct ring_buffer *rb, int map_fd,
r->mask = info.max_entries - 1;
/* Map writable consumer page */
- tmp = mmap(NULL, rb->page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
- map_fd, 0);
+ tmp = mmap(NULL, rb->page_size, PROT_READ | PROT_WRITE, MAP_SHARED, map_fd, 0);
if (tmp == MAP_FAILED) {
err = -errno;
pr_warn("ringbuf: failed to mmap consumer page for map fd=%d: %d\n",
@@ -111,8 +111,12 @@ int ring_buffer__add(struct ring_buffer *rb, int map_fd,
* data size to allow simple reading of samples that wrap around the
* end of a ring buffer. See kernel implementation for details.
* */
- tmp = mmap(NULL, rb->page_size + 2 * info.max_entries, PROT_READ,
- MAP_SHARED, map_fd, rb->page_size);
+ mmap_sz = rb->page_size + 2 * (__u64)info.max_entries;
+ if (mmap_sz != (__u64)(size_t)mmap_sz) {
+ pr_warn("ringbuf: ring buffer size (%u) is too big\n", info.max_entries);
+ return -E2BIG;
+ }
+ tmp = mmap(NULL, (size_t)mmap_sz, PROT_READ, MAP_SHARED, map_fd, rb->page_size);
if (tmp == MAP_FAILED) {
err = -errno;
ringbuf_unmap_ring(rb, r);