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| author |   Ilya Maximets <i.maximets@ovn.org> | 2019-10-09 18:49:29 +0200 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2019-10-09 15:45:37 -0700 |
| commit | 25bfef430e960e695403b5d9c8dcc11b9f5d62be (patch) | |
| tree | 8b4349590cbbdc4f2c6444d6b92c5437fc8b6b07 /tools/lib/bpf/xsk.c | |
| parent | Merge branch 'btf2c-padding' (diff) | |
| download | linux-25bfef430e960e695403b5d9c8dcc11b9f5d62be.tar.xz linux-25bfef430e960e695403b5d9c8dcc11b9f5d62be.zip | |
libbpf: Fix passing uninitialized bytes to setsockopt
'struct xdp_umem_reg' has 4 bytes of padding at the end that makes
valgrind complain about passing uninitialized stack memory to the
syscall:
Syscall param socketcall.setsockopt() points to uninitialised byte(s)
at 0x4E7AB7E: setsockopt (in /usr/lib64/libc-2.29.so)
by 0x4BDE035: xsk_umem__create@@LIBBPF_0.0.4 (xsk.c:172)
Uninitialised value was created by a stack allocation
at 0x4BDDEBA: xsk_umem__create@@LIBBPF_0.0.4 (xsk.c:140)
Padding bytes appeared after introducing of a new 'flags' field.
memset() is required to clear them.
Fixes: 10d30e301732 ("libbpf: add flags to umem config")
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191009164929.17242-1-i.maximets@ovn.org
Diffstat (limited to 'tools/lib/bpf/xsk.c')
| -rw-r--r-- | tools/lib/bpf/xsk.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index 24fa313524fb..b0f532544c91 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -163,6 +163,7 @@ int xsk_umem__create_v0_0_4(struct xsk_umem **umem_ptr, void *umem_area, umem->umem_area = umem_area; xsk_set_umem_config(&umem->config, usr_config); + memset(&mr, 0, sizeof(mr)); mr.addr = (uintptr_t)umem_area; mr.len = size; mr.chunk_size = umem->config.frame_size; |