From cfd4921049269ee6765b4a1cb820b95d0df5dda5 Mon Sep 17 00:00:00 2001 From: Michal Rostecki Date: Wed, 29 May 2019 20:31:09 +0200 Subject: libbpf: Return btf_fd for load_sk_storage_btf Before this change, function load_sk_storage_btf expected that libbpf__probe_raw_btf was returning a BTF descriptor, but in fact it was returning an information about whether the probe was successful (0 or 1). load_sk_storage_btf was using that value as an argument of the close function, which was resulting in closing stdout and thus terminating the process which called that function. That bug was visible in bpftool. `bpftool feature` subcommand was always exiting too early (because of closed stdout) and it didn't display all requested probes. `bpftool -j feature` or `bpftool -p feature` were not returning a valid json object. This change renames the libbpf__probe_raw_btf function to libbpf__load_raw_btf, which now returns a BTF descriptor, as expected in load_sk_storage_btf. v2: - Fix typo in the commit message. v3: - Simplify BTF descriptor handling in bpf_object__probe_btf_* functions. - Rename libbpf__probe_raw_btf function to libbpf__load_raw_btf and return a BTF descriptor. v4: - Fix typo in the commit message. Fixes: d7c4b3980c18 ("libbpf: detect supported kernel BTF features and sanitize BTF") Signed-off-by: Michal Rostecki Acked-by: Andrii Nakryiko Acked-by: Song Liu Signed-off-by: Alexei Starovoitov --- tools/lib/bpf/libbpf.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) (limited to 'tools/lib/bpf/libbpf.c') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 197b574406b3..5d046cc7b207 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1645,14 +1645,16 @@ static int bpf_object__probe_btf_func(struct bpf_object *obj) /* FUNC x */ /* [3] */ BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), }; - int res; + int btf_fd; - res = libbpf__probe_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs)); - if (res < 0) - return res; - if (res > 0) + btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs)); + if (btf_fd >= 0) { obj->caps.btf_func = 1; + close(btf_fd); + return 1; + } + return 0; } @@ -1670,14 +1672,16 @@ static int bpf_object__probe_btf_datasec(struct bpf_object *obj) BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), BTF_VAR_SECINFO_ENC(2, 0, 4), }; - int res; + int btf_fd; - res = libbpf__probe_raw_btf((char *)types, sizeof(types), - strs, sizeof(strs)); - if (res < 0) - return res; - if (res > 0) + btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types), + strs, sizeof(strs)); + if (btf_fd >= 0) { obj->caps.btf_datasec = 1; + close(btf_fd); + return 1; + } + return 0; } -- cgit From 9bb59ac1f6c362f14b58187bc56e737780c52c19 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 7 Jun 2019 01:48:59 +0200 Subject: bpf, libbpf: enable recvmsg attach types Another trivial patch to libbpf in order to enable identifying and attaching programs to BPF_CGROUP_UDP{4,6}_RECVMSG by section name. Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov --- tools/lib/bpf/libbpf.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'tools/lib/bpf/libbpf.c') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 5d046cc7b207..151f7ac1882e 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3210,6 +3210,10 @@ static const struct { BPF_CGROUP_UDP4_SENDMSG), BPF_EAPROG_SEC("cgroup/sendmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_UDP6_SENDMSG), + BPF_EAPROG_SEC("cgroup/recvmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + BPF_CGROUP_UDP4_RECVMSG), + BPF_EAPROG_SEC("cgroup/recvmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + BPF_CGROUP_UDP6_RECVMSG), BPF_EAPROG_SEC("cgroup/sysctl", BPF_PROG_TYPE_CGROUP_SYSCTL, BPF_CGROUP_SYSCTL), }; -- cgit