Yonghong Song 332270fdc8 bpf: enhance verifier to understand stack pointer arithmetic ... llvm 4.0 and above generates the code like below: .... 440: (b7) r1 = 15 441: (05) goto pc+73 515: (79) r6 = *(u64 *)(r10 -152) 516: (bf) r7 = r10 517: (07) r7 += -112 518: (bf) r2 = r7 519: (0f) r2 += r1 520: (71) r1 = *(u8 *)(r8 +0) 521: (73) *(u8 *)(r2 +45) = r1 .... and the verifier complains "R2 invalid mem access 'inv'" for insn #521. This is because verifier marks register r2 as unknown value after #519 where r2 is a stack pointer and r1 holds a constant value. Teach verifier to recognize "stack_ptr + imm" and "stack_ptr + reg with const val" as valid stack_ptr with new offset. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>		2017-05-01 11:40:23 -04:00
..
arraymap.c	bpf: map_get_next_key to return first key on NULL	2017-04-25 11:57:45 -04:00
bpf_lru_list.c	bpf: lru: Lower the PERCPU_NR_SCANS from 16 to 4	2017-04-17 13:55:52 -04:00
bpf_lru_list.h
cgroup.c	bpf: pass sk to helper functions	2017-04-11 14:54:19 -04:00
core.c	bpf: bpf_lock on kallsysms doesn't need to be irqsave	2017-04-28 15:48:14 -04:00
hashtab.c	bpf: map_get_next_key to return first key on NULL	2017-04-25 11:57:45 -04:00
helpers.c
inode.c
lpm_trie.c	bpf: remove struct bpf_map_type_list	2017-04-11 14:38:43 -04:00
Makefile
map_in_map.c
map_in_map.h
percpu_freelist.c
percpu_freelist.h
stackmap.c	bpf: remove struct bpf_map_type_list	2017-04-11 14:38:43 -04:00
syscall.c	bpf: map_get_next_key to return first key on NULL	2017-04-25 11:57:45 -04:00
verifier.c	bpf: enhance verifier to understand stack pointer arithmetic	2017-05-01 11:40:23 -04:00