bpf: Emit explicit NULL pointer checks for PROBE_LDX instructions.

Browse source

PTR_TO_BTF_ID registers contain either kernel pointer or NULL.
Emit the NULL check explicitly by JIT instead of going into
do_user_addr_fault() on NULL deference.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210202053837.95909-1-alexei.starovoitov@gmail.com

...

This commit is contained in:

Alexei Starovoitov 2021-02-01 21:38:37 -08:00 • committed by Daniel Borkmann

parent 5f10c1aac8

commit 4c5de12759

1 changed files with 19 additions and 0 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

19

arch/x86/net/bpf_jit_comp.c

View file