linux/kernel/bpf
Lorenz Bauer 9436ef6e86 bpf: Allow specifying a BTF ID per argument in function protos
Function prototypes using ARG_PTR_TO_BTF_ID currently use two ways to signal
which BTF IDs are acceptable. First, bpf_func_proto.btf_id is an array of
IDs, one for each argument. This array is only accessed up to the highest
numbered argument that uses ARG_PTR_TO_BTF_ID and may therefore be less than
five arguments long. It usually points at a BTF_ID_LIST. Second, check_btf_id
is a function pointer that is called by the verifier if present. It gets the
actual BTF ID of the register, and the argument number we're currently checking.
It turns out that the only user check_arg_btf_id ignores the argument, and is
simply used to check whether the BTF ID has a struct sock_common at it's start.

Replace both of these mechanisms with an explicit BTF ID for each argument
in a function proto. Thanks to btf_struct_ids_match this is very flexible:
check_arg_btf_id can be replaced by requiring struct sock_common.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200921121227.255763-5-lmb@cloudflare.com
2020-09-21 15:00:40 -07:00
..
preload bpf: Disallow BPF_PRELOAD in allmodconfig builds 2020-08-25 15:23:46 -07:00
arraymap.c bpf, x64: rework pro/epilogue and tailcall handling in JIT 2020-09-17 19:55:30 -07:00
bpf_inode_storage.c bpf: Allow specifying a BTF ID per argument in function protos 2020-09-21 15:00:40 -07:00
bpf_iter.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-09-01 13:22:59 -07:00
bpf_local_storage.c bpf: Use hlist_add_head_rcu when linking to local_storage 2020-09-19 01:12:35 +02:00
bpf_lru_list.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
bpf_lru_list.h bpf: Fix a typo "inacitve" -> "inactive" 2020-04-06 21:54:10 +02:00
bpf_lsm.c bpf: Allow local storage to be used from LSM programs 2020-08-25 15:00:04 -07:00
bpf_struct_ops_types.h bpf: tcp: Support tcp_congestion_ops in bpf 2020-01-09 08:46:18 -08:00
bpf_struct_ops.c bpf: Move btf_resolve_size into __btf_resolve_size 2020-08-25 15:37:41 -07:00
btf.c bpf: Allow specifying a BTF ID per argument in function protos 2020-09-21 15:00:40 -07:00
cgroup.c bpf: Add support for forced LINK_DETACH command 2020-08-01 20:38:28 -07:00
core.c bpf, x64: rework pro/epilogue and tailcall handling in JIT 2020-09-17 19:55:30 -07:00
cpumap.c bpf: {cpu,dev}map: Change various functions return type from int to void 2020-09-01 15:45:58 +02:00
devmap.c bpf: {cpu,dev}map: Change various functions return type from int to void 2020-09-01 15:45:58 +02:00
disasm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
disasm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
dispatcher.c bpf: Remove bpf_image tree 2020-03-13 12:49:52 -07:00
hashtab.c bpf: Introduce sleepable BPF programs 2020-08-28 21:20:33 +02:00
helpers.c bpf: Add bpf_copy_from_user() helper. 2020-08-28 21:20:33 +02:00
inode.c bpf: Add kernel module with user mode driver that populates bpffs. 2020-08-20 16:02:36 +02:00
local_storage.c bpf/local_storage: Fix build without CONFIG_CGROUP 2020-07-25 20:16:36 -07:00
lpm_trie.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
Makefile bpf: Implement bpf_local_storage for inodes 2020-08-25 15:00:04 -07:00
map_in_map.c bpf: Relax max_entries check for most of the inner map types 2020-08-28 15:41:30 +02:00
map_in_map.h bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
map_iter.c bpf: Implement link_query callbacks in map element iterators 2020-08-21 14:01:39 -07:00
net_namespace.c bpf: Add support for forced LINK_DETACH command 2020-08-01 20:38:28 -07:00
offload.c bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fill 2020-02-17 16:53:49 +01:00
percpu_freelist.c bpf: Dont iterate over possible CPUs with interrupts disabled 2020-02-24 16:18:20 -08:00
percpu_freelist.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
prog_iter.c bpf: Refactor bpf_iter_reg to have separate seq_info member 2020-07-25 20:16:32 -07:00
queue_stack_maps.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
reuseport_array.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
ringbuf.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
stackmap.c bpf: Allow specifying a BTF ID per argument in function protos 2020-09-21 15:00:40 -07:00
syscall.c bpf: Fix potential call bpf_link_free() in atomic context 2020-09-21 21:20:17 +02:00
sysfs_btf.c bpf: Support llvm-objcopy for vmlinux BTF 2020-03-19 12:32:38 +01:00
task_iter.c bpf: Avoid iterating duplicated files for task_file iterator 2020-09-02 16:40:33 +02:00
tnum.c bpf: Verifier, do explicit ALU32 bounds tracking 2020-03-30 14:59:53 -07:00
trampoline.c bpf: Remove bpf_lsm_file_mprotect from sleepable list. 2020-08-31 23:03:57 +02:00
verifier.c bpf: Allow specifying a BTF ID per argument in function protos 2020-09-21 15:00:40 -07:00