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| author | Martin Kelly <martin.kelly@crowdstrike.com> | 2023-09-25 14:50:32 -0700 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2023-09-25 16:22:42 -0700 |
| commit | 4448f64c549c28175dd9af4e8f9a2e0c62ef6d38 (patch) | |
| tree | a99117dde3b9d965c92594e16f65b6c3632060ca /tools/lib | |
| parent | 831916fb93d4b99bd5f18b8530708b88d901a522 (diff) | |
| download | linux-4448f64c549c28175dd9af4e8f9a2e0c62ef6d38.tar.gz | |
libbpf: Refactor cleanup in ring_buffer__add
Refactor the cleanup code in ring_buffer__add to use a unified err_out
label. This reduces code duplication, as well as plugging a potential
leak if mmap_sz != (__u64)(size_t)mmap_sz (currently this would miss
unmapping tmp because ringbuf_unmap_ring isn't called).
Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230925215045.2375758-2-martin.kelly@crowdstrike.com
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/ringbuf.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/tools/lib/bpf/ringbuf.c b/tools/lib/bpf/ringbuf.c index 02199364db136..29b0d19d920fe 100644 --- a/tools/lib/bpf/ringbuf.c +++ b/tools/lib/bpf/ringbuf.c @@ -121,7 +121,7 @@ int ring_buffer__add(struct ring_buffer *rb, int map_fd, err = -errno; pr_warn("ringbuf: failed to mmap consumer page for map fd=%d: %d\n", map_fd, err); - return libbpf_err(err); + goto err_out; } r->consumer_pos = tmp; @@ -131,16 +131,16 @@ int ring_buffer__add(struct ring_buffer *rb, int map_fd, */ mmap_sz = rb->page_size + 2 * (__u64)info.max_entries; if (mmap_sz != (__u64)(size_t)mmap_sz) { + err = -E2BIG; pr_warn("ringbuf: ring buffer size (%u) is too big\n", info.max_entries); - return libbpf_err(-E2BIG); + goto err_out; } 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); pr_warn("ringbuf: failed to mmap data pages for map fd=%d: %d\n", map_fd, err); - return libbpf_err(err); + goto err_out; } r->producer_pos = tmp; r->data = tmp + rb->page_size; @@ -152,14 +152,17 @@ int ring_buffer__add(struct ring_buffer *rb, int map_fd, e->data.fd = rb->ring_cnt; if (epoll_ctl(rb->epoll_fd, EPOLL_CTL_ADD, map_fd, e) < 0) { err = -errno; - ringbuf_unmap_ring(rb, r); pr_warn("ringbuf: failed to epoll add map fd=%d: %d\n", map_fd, err); - return libbpf_err(err); + goto err_out; } rb->ring_cnt++; return 0; + +err_out: + ringbuf_unmap_ring(rb, r); + return libbpf_err(err); } void ring_buffer__free(struct ring_buffer *rb) |