From 7d1982b4e335c1b184406b7566f6041bfe313c35 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 15 Jun 2018 02:30:47 +0200 Subject: bpf: fix panic in prog load calls cleanup While testing I found that when hitting error path in bpf_prog_load() where we jump to free_used_maps and prog contained BPF to BPF calls that were JITed earlier, then we never clean up the bpf_prog_kallsyms_add() done under jit_subprogs(). Add proper API to make BPF kallsyms deletion more clear and fix that. Fixes: 1c2a088a6626 ("bpf: x64: add JIT support for multi-function programs") Signed-off-by: Daniel Borkmann Acked-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov --- kernel/bpf/syscall.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'kernel/bpf/syscall.c') diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 0fa20624707f..0f62692fe635 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1034,14 +1034,9 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu) static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) { if (atomic_dec_and_test(&prog->aux->refcnt)) { - int i; - /* bpf_prog_free_id() must be called first */ bpf_prog_free_id(prog, do_idr_lock); - - for (i = 0; i < prog->aux->func_cnt; i++) - bpf_prog_kallsyms_del(prog->aux->func[i]); - bpf_prog_kallsyms_del(prog); + bpf_prog_kallsyms_del_all(prog); call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); } @@ -1384,6 +1379,7 @@ static int bpf_prog_load(union bpf_attr *attr) return err; free_used_maps: + bpf_prog_kallsyms_del_subprogs(prog); free_used_maps(prog->aux); free_prog: bpf_prog_uncharge_memlock(prog); -- cgit v1.2.3