From af91acbc62999d62e2ca1e80f660d20561ca55d3 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Wed, 30 Oct 2019 16:30:19 -0700 Subject: bpf: Fix bpf jit kallsym access Jiri reported crash when JIT is on, but net.core.bpf_jit_kallsyms is off. bpf_prog_kallsyms_find() was skipping addr->bpf_prog resolution logic in oops and stack traces. That's incorrect. It should only skip addr->name resolution for 'cat /proc/kallsyms'. That's what bpf_jit_kallsyms and bpf_jit_harden protect. Fixes: 3dec541b2e63 ("bpf: Add support for BTF pointers to x86 JIT") Reported-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20191030233019.1187404-1-ast@kernel.org --- kernel/bpf/core.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 673f5d40a93e..8d3fbc86ca5e 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -668,9 +668,6 @@ static struct bpf_prog *bpf_prog_kallsyms_find(unsigned long addr) { struct latch_tree_node *n; - if (!bpf_jit_kallsyms_enabled()) - return NULL; - n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops); return n ? container_of(n, struct bpf_prog_aux, ksym_tnode)->prog : -- cgit v1.2.3-59-g8ed1b