Yonghong Song 31fd85816d bpf: permits narrower load from bpf program context fields ... Currently, verifier will reject a program if it contains an narrower load from the bpf context structure. For example, __u8 h = __sk_buff->hash, or __u16 p = __sk_buff->protocol __u32 sample_period = bpf_perf_event_data->sample_period which are narrower loads of 4-byte or 8-byte field. This patch solves the issue by: . Introduce a new parameter ctx_field_size to carry the field size of narrower load from prog type specific *__is_valid_access validator back to verifier. . The non-zero ctx_field_size for a memory access indicates (1). underlying prog type specific convert_ctx_accesses supporting non-whole-field access (2). the current insn is a narrower or whole field access. . In verifier, for such loads where load memory size is less than ctx_field_size, verifier transforms it to a full field load followed by proper masking. . Currently, __sk_buff and bpf_perf_event_data->sample_period are supporting narrowing loads. . Narrower stores are still not allowed as typical ctx stores are just normal stores. Because of this change, some tests in verifier will fail and these tests are removed. As a bonus, rename some out of bound __sk_buff->cb access to proper field name and remove two redundant "skb cb oob" tests. Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2017-06-14 14:56:25 -04:00
..
arraymap.c	perf, bpf: Add BPF support to all perf_event types	2017-06-04 21:58:01 -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	bpf: Add percpu LRU list	2016-11-15 11:50:20 -05:00
cgroup.c	bpf: pass sk to helper functions	2017-04-11 14:54:19 -04:00
core.c	bpf: use different interpreter depending on required stack size	2017-05-31 19:29:48 -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	bpf: rename ARG_PTR_TO_STACK	2017-01-09 16:56:27 -05:00
inode.c	fs: constify tree_descr arrays passed to simple_fill_super()	2017-04-26 23:54:06 -04:00
lpm_trie.c	bpf: fix wrong exposure of map_flags into fdinfo for lpm	2017-05-25 13:44:28 -04:00
Makefile	bpf: Add array of maps support	2017-03-22 15:45:45 -07:00
map_in_map.c	bpf: Add array of maps support	2017-03-22 15:45:45 -07:00
map_in_map.h	bpf: Add array of maps support	2017-03-22 15:45:45 -07:00
percpu_freelist.c	bpf: introduce percpu_freelist	2016-03-08 15:28:31 -05:00
percpu_freelist.h	bpf: introduce percpu_freelist	2016-03-08 15:28:31 -05:00
stackmap.c	bpf: fix wrong exposure of map_flags into fdinfo for lpm	2017-05-25 13:44:28 -04:00
syscall.c	bpf: Add BPF_OBJ_GET_INFO_BY_FD	2017-06-06 15:41:24 -04:00
verifier.c	bpf: permits narrower load from bpf program context fields	2017-06-14 14:56:25 -04:00