From: Lorenz Bauer <lmb@cloudflare.com>
Date: Tue, 8 Jan 2019 13:58:00 +0000
Subject: bpf: libbpf: retry loading program on EAGAIN
Patch-mainline: v5.0-rc3
Git-commit: 86edaed379632e216a97e6bcef9f498b64522d50
References: bsc#1109837
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@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
tools/lib/bpf/bpf.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -65,6 +65,17 @@ static inline int sys_bpf(enum bpf_cmd c
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;
@@ -198,7 +209,7 @@ int bpf_load_program_xattr(const struct
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;
@@ -207,7 +218,7 @@ int bpf_load_program_xattr(const struct
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,
@@ -248,7 +259,7 @@ int bpf_verify_program(enum bpf_prog_typ
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,