From 9c82a63cf3701b78cd092c69c3e75ff806837194 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Fri, 19 Jun 2020 16:04:22 -0700 Subject: libbpf: Fix CO-RE relocs against .text section bpf_object__find_program_by_title(), used by CO-RE relocation code, doesn't return .text "BPF program", if it is a function storage for sub-programs. Because of that, any CO-RE relocation in helper non-inlined functions will fail. Fix this by searching for .text-corresponding BPF program manually. Adjust one of bpf_iter selftest to exhibit this pattern. Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") Reported-by: Yonghong Song Signed-off-by: Andrii Nakryiko Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20200619230423.691274-1-andriin@fb.com --- tools/lib/bpf/libbpf.c | 8 +++++++- tools/testing/selftests/bpf/progs/bpf_iter_netlink.c | 2 +- 2 files changed, 8 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 477c679ed945..f17151d866e6 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4818,7 +4818,13 @@ bpf_core_reloc_fields(struct bpf_object *obj, const char *targ_btf_path) err = -EINVAL; goto out; } - prog = bpf_object__find_program_by_title(obj, sec_name); + prog = NULL; + for (i = 0; i < obj->nr_programs; i++) { + if (!strcmp(obj->programs[i].section_name, sec_name)) { + prog = &obj->programs[i]; + break; + } + } if (!prog) { pr_warn("failed to find program '%s' for CO-RE offset relocation\n", sec_name); diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c b/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c index e7b8753eac0b..75ecf956a2df 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_netlink.c @@ -25,7 +25,7 @@ struct bpf_iter__netlink { struct netlink_sock *sk; } __attribute__((preserve_access_index)); -static inline struct inode *SOCK_INODE(struct socket *socket) +static __attribute__((noinline)) struct inode *SOCK_INODE(struct socket *socket) { return &container_of(socket, struct socket_alloc, socket)->vfs_inode; } -- cgit v1.2.3-59-g8ed1b