From f75a697e091375c96c35f733a664e3557171f28b Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Tue, 15 Oct 2019 20:24:59 -0700 Subject: libbpf: Auto-detect btf_id of BTF-based raw_tracepoints It's a responsiblity of bpf program author to annotate the program with SEC("tp_btf/name") where "name" is a valid raw tracepoint. The libbpf will try to find "name" in vmlinux BTF and error out in case vmlinux BTF is not available or "name" is not found. If "name" is indeed a valid raw tracepoint then in-kernel BTF will have "btf_trace_##name" typedef that points to function prototype of that raw tracepoint. BTF description captures exact argument the kernel C code is passing into raw tracepoint. The kernel verifier will check the types while loading bpf program. libbpf keeps BTF type id in expected_attach_type, but since kernel ignores this attribute for tracing programs copy it into attach_btf_id attribute before loading. Later the kernel will use prog->attach_btf_id to select raw tracepoint during bpf_raw_tracepoint_open syscall command. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20191016032505.2089704-6-ast@kernel.org --- tools/lib/bpf/bpf.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools/lib/bpf/bpf.c') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index cbb933532981..79046067720f 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -228,6 +228,9 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, memset(&attr, 0, sizeof(attr)); attr.prog_type = load_attr->prog_type; attr.expected_attach_type = load_attr->expected_attach_type; + if (attr.prog_type == BPF_PROG_TYPE_RAW_TRACEPOINT) + /* expected_attach_type is ignored for tracing progs */ + attr.attach_btf_id = attr.expected_attach_type; attr.insn_cnt = (__u32)load_attr->insns_cnt; attr.insns = ptr_to_u64(load_attr->insns); attr.license = ptr_to_u64(load_attr->license); -- cgit v1.2.3 From 12a8654b2e5aab37b22c9608d008f9f0565862c0 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 30 Oct 2019 15:32:12 -0700 Subject: libbpf: Add support for prog_tracing Cleanup libbpf from expected_attach_type == attach_btf_id hack and introduce BPF_PROG_TYPE_TRACING. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Acked-by: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20191030223212.953010-3-ast@kernel.org --- tools/lib/bpf/bpf.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'tools/lib/bpf/bpf.c') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 79046067720f..ca0d635b1d5e 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -228,9 +228,10 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, memset(&attr, 0, sizeof(attr)); attr.prog_type = load_attr->prog_type; attr.expected_attach_type = load_attr->expected_attach_type; - if (attr.prog_type == BPF_PROG_TYPE_RAW_TRACEPOINT) - /* expected_attach_type is ignored for tracing progs */ - attr.attach_btf_id = attr.expected_attach_type; + if (attr.prog_type == BPF_PROG_TYPE_TRACING) + attr.attach_btf_id = load_attr->attach_btf_id; + else + attr.prog_ifindex = load_attr->prog_ifindex; attr.insn_cnt = (__u32)load_attr->insns_cnt; attr.insns = ptr_to_u64(load_attr->insns); attr.license = ptr_to_u64(load_attr->license); @@ -245,7 +246,6 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, } attr.kern_version = load_attr->kern_version; - attr.prog_ifindex = load_attr->prog_ifindex; attr.prog_btf_fd = load_attr->prog_btf_fd; attr.func_info_rec_size = load_attr->func_info_rec_size; attr.func_info_cnt = load_attr->func_info_cnt; -- cgit v1.2.3 From 4ee1135615713387b869dfd099ffdf8656be6784 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Wed, 6 Nov 2019 18:08:52 -0800 Subject: libbpf: Fix potential overflow issue Fix a potential overflow issue found by LGTM analysis, based on Github libbpf source code. Fixes: 3d65014146c6 ("bpf: libbpf: Add btf_line_info support to libbpf") Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20191107020855.3834758-3-andriin@fb.com --- tools/lib/bpf/bpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/lib/bpf/bpf.c') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index ca0d635b1d5e..b3e3e99a0f28 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -189,7 +189,7 @@ static void * alloc_zero_tailing_info(const void *orecord, __u32 cnt, __u32 actual_rec_size, __u32 expected_rec_size) { - __u64 info_len = actual_rec_size * cnt; + __u64 info_len = (__u64)actual_rec_size * cnt; void *info, *nrecord; int i; -- cgit v1.2.3 From e7bf94dbb882b7d679a6a18e40e4f28076eb249f Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 14 Nov 2019 10:57:18 -0800 Subject: libbpf: Add support for attaching BPF programs to other BPF programs Extend libbpf api to pass attach_prog_fd into bpf_object__open. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20191114185720.1641606-19-ast@kernel.org --- tools/lib/bpf/bpf.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'tools/lib/bpf/bpf.c') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index b3e3e99a0f28..98596e15390f 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -228,10 +228,13 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, memset(&attr, 0, sizeof(attr)); attr.prog_type = load_attr->prog_type; attr.expected_attach_type = load_attr->expected_attach_type; - if (attr.prog_type == BPF_PROG_TYPE_TRACING) + if (attr.prog_type == BPF_PROG_TYPE_TRACING) { attr.attach_btf_id = load_attr->attach_btf_id; - else + attr.attach_prog_fd = load_attr->attach_prog_fd; + } else { attr.prog_ifindex = load_attr->prog_ifindex; + attr.kern_version = load_attr->kern_version; + } attr.insn_cnt = (__u32)load_attr->insns_cnt; attr.insns = ptr_to_u64(load_attr->insns); attr.license = ptr_to_u64(load_attr->license); @@ -245,7 +248,6 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, attr.log_size = 0; } - attr.kern_version = load_attr->kern_version; attr.prog_btf_fd = load_attr->prog_btf_fd; attr.func_info_rec_size = load_attr->func_info_rec_size; attr.func_info_cnt = load_attr->func_info_cnt; -- cgit v1.2.3