From: Lorenz Bauer <lmb@xxxxxxxxxxxxxx> [ Upstream commit 86edaed379632e216a97e6bcef9f498b64522d50 ] Commit c3494801cd17 ("bpf: check pending signals while verifying programs") makes it possible for the BPF_PROG_LOAD to fail with EAGAIN. Retry unconditionally in this case. Fixes: c3494801cd17 ("bpf: check pending signals while verifying programs") Signed-off-by: Lorenz Bauer <lmb@xxxxxxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/lib/bpf/bpf.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index dd0b68d1f4be0..482025b728399 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -75,6 +75,17 @@ static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr, return syscall(__NR_bpf, cmd, attr, size); } +static inline int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size) +{ + int fd; + + do { + fd = sys_bpf(BPF_PROG_LOAD, attr, size); + } while (fd < 0 && errno == EAGAIN); + + return fd; +} + int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr) { __u32 name_len = create_attr->name ? strlen(create_attr->name) : 0; @@ -218,7 +229,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, memcpy(attr.prog_name, load_attr->name, min(name_len, BPF_OBJ_NAME_LEN - 1)); - fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + fd = sys_bpf_prog_load(&attr, sizeof(attr)); if (fd >= 0 || !log_buf || !log_buf_sz) return fd; @@ -227,7 +238,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, attr.log_size = log_buf_sz; attr.log_level = 1; log_buf[0] = 0; - return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + return sys_bpf_prog_load(&attr, sizeof(attr)); } int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns, @@ -268,7 +279,7 @@ int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns, attr.kern_version = kern_version; attr.prog_flags = strict_alignment ? BPF_F_STRICT_ALIGNMENT : 0; - return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); + return sys_bpf_prog_load(&attr, sizeof(attr)); } int bpf_map_update_elem(int fd, const void *key, const void *value, -- 2.20.1