bpf, x86: Fall back to interpreter mode when extra pass fails
authorHou Tao <houtao1@huawei.com>
Wed, 9 Mar 2022 12:33:18 +0000 (20:33 +0800)
committerAlexei Starovoitov <ast@kernel.org>
Wed, 16 Mar 2022 22:12:18 +0000 (15:12 -0700)
commit73e14451f39e54f83ea3badb6d6b8a423f901845
tree137bebfa791a5058aa800f7a4a6d7b9081bbe6d0
parentaaccdf9c93a00cc5eec6f9d97046b44643c60800
bpf, x86: Fall back to interpreter mode when extra pass fails

Extra pass for subprog jit may fail (e.g. due to bpf_jit_harden race),
but bpf_func is not cleared for the subprog and jit_subprogs will
succeed. The running of the bpf program may lead to oops because the
memory for the jited subprog image has already been freed.

So fall back to interpreter mode by clearing bpf_func/jited/jited_len
when extra pass fails.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220309123321.2400262-2-houtao1@huawei.com
arch/x86/net/bpf_jit_comp.c