bpf: support raw tracepoints in modules
Distributions build drivers as modules, including network and filesystem
drivers which export numerous tracepoints. This enables
bpf(BPF_RAW_TRACEPOINT_OPEN) to attach to those tracepoints.
Signed-off-by: Matt Mullins <mmullins@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 5db3106..0607db3 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1604,6 +1604,7 @@ static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
bpf_prog_put(raw_tp->prog);
}
+ bpf_put_raw_tracepoint(raw_tp->btp);
kfree(raw_tp);
return 0;
}
@@ -1629,13 +1630,15 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
return -EFAULT;
tp_name[sizeof(tp_name) - 1] = 0;
- btp = bpf_find_raw_tracepoint(tp_name);
+ btp = bpf_get_raw_tracepoint(tp_name);
if (!btp)
return -ENOENT;
raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
- if (!raw_tp)
- return -ENOMEM;
+ if (!raw_tp) {
+ err = -ENOMEM;
+ goto out_put_btp;
+ }
raw_tp->btp = btp;
prog = bpf_prog_get_type(attr->raw_tracepoint.prog_fd,
@@ -1663,6 +1666,8 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
bpf_prog_put(prog);
out_free_tp:
kfree(raw_tp);
+out_put_btp:
+ bpf_put_raw_tracepoint(btp);
return err;
}