diff options
| author | Andrii Nakryiko <andrii@kernel.org> | 2020-12-03 12:46:21 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-12-03 17:38:20 -0800 |
| commit | 12cc126df82c96c89706aa207ad27c56f219047c (patch) | |
| tree | 481eb62be58a08f279c73fd34f2d9f9f16c786af /kernel/trace | |
| parent | cadd64807cd83e2213dcb70f93d12d978c02b5fa (diff) | |
bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address()
__module_address() needs to be called with preemption disabled or with
module_mutex taken. preempt_disable() is enough for read-only uses, which is
what this fix does. Also, module_put() does internal check for NULL, so drop
it as well.
Fixes: a38d1107f937 ("bpf: support raw tracepoints in modules")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-2-andrii@kernel.org
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/bpf_trace.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index d255bc9b2bfa..23a390aac524 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2060,10 +2060,12 @@ struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name) void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) { - struct module *mod = __module_address((unsigned long)btp); + struct module *mod; - if (mod) - module_put(mod); + preempt_disable(); + mod = __module_address((unsigned long)btp); + module_put(mod); + preempt_enable(); } static __always_inline |