linux-stable.git/include/linux/btf_ids.h, branch v5.17.7

bpf: Introduce btf_tracing_ids

2021-11-12T18:19:09+00:00

Similar to btf_sock_ids, btf_tracing_ids provides btf ID for task_struct,
file, and vm_area_struct via easy to understand format like
btf_tracing_ids[BTF_TRACING_TYPE_[TASK|file|VMA]].

Suggested-by: Alexei Starovoitov 
Signed-off-by: Song Liu 
Signed-off-by: Alexei Starovoitov 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20211112150243.1270987-3-songliubraving@fb.com

bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs

2021-11-12T18:19:09+00:00

syzbot reported the following BUG w/o CONFIG_DEBUG_INFO_BTF

BUG: KASAN: global-out-of-bounds in task_iter_init+0x212/0x2e7 kernel/bpf/task_iter.c:661
Read of size 4 at addr ffffffff90297404 by task swapper/0/1

CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.15.0-syzkaller #0
Hardware name: ... Google Compute Engine, BIOS Google 01/01/2011
Call Trace:

__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0xf/0x309 mm/kasan/report.c:256
__kasan_report mm/kasan/report.c:442 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
task_iter_init+0x212/0x2e7 kernel/bpf/task_iter.c:661
do_one_initcall+0x103/0x650 init/main.c:1295
do_initcall_level init/main.c:1368 [inline]
do_initcalls init/main.c:1384 [inline]
do_basic_setup init/main.c:1403 [inline]
kernel_init_freeable+0x6b1/0x73a init/main.c:1606
kernel_init+0x1a/0x1d0 init/main.c:1497
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295


This is caused by hard-coded name[1] in BTF_ID_LIST_GLOBAL (w/o
CONFIG_DEBUG_INFO_BTF). Fix this by adding a parameter n to
BTF_ID_LIST_GLOBAL. This avoids ifdef CONFIG_DEBUG_INFO_BTF in btf.c and
filter.c.

Fixes: 7c7e3d31e785 ("bpf: Introduce helper bpf_find_vma")
Reported-by: syzbot+e0d81ec552a21d9071aa@syzkaller.appspotmail.com
Reported-by: Eric Dumazet 
Suggested-by: Eric Dumazet 
Signed-off-by: Song Liu 
Signed-off-by: Alexei Starovoitov 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20211112150243.1270987-2-songliubraving@fb.com

bpf: Fix bpf-next builds without CONFIG_BPF_EVENTS

2021-08-26T02:41:39+00:00

This commit fixes linker errors along the lines of:

    s390-linux-ld: task_iter.c:(.init.text+0xa4): undefined reference to `btf_task_struct_ids'`

Fix by defining btf_task_struct_ids unconditionally in kernel/bpf/btf.c
since there exists code that unconditionally uses btf_task_struct_ids.

Reported-by: kernel test robot 
Signed-off-by: Daniel Xu 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/05d94748d9f4b3eecedc4fddd6875418a396e23c.1629942444.git.dxu@dxuuu.xyz

bpf: Consolidate task_struct BTF_ID declarations

2021-08-25T17:37:05+00:00

No need to have it defined 5 times. Once is enough.

Signed-off-by: Daniel Xu 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/6dcefa5bed26fe1226f26683f36819bb53ec19a2.1629772842.git.dxu@dxuuu.xyz

bpf: Add BTF_ID_LIST_GLOBAL_SINGLE macro

2021-08-25T17:37:05+00:00

Same as BTF_ID_LIST_SINGLE macro except defines a global ID.

Signed-off-by: Daniel Xu 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/a867a97517df42fd3953eeb5454402b57e74538f.1629772842.git.dxu@dxuuu.xyz

bpf: af_unix: Implement BPF iterator for UNIX domain socket.

2021-08-15T07:13:32+00:00

This patch implements the BPF iterator for the UNIX domain socket.

Currently, the batch optimisation introduced for the TCP iterator in the
commit 04c7820b776f ("bpf: tcp: Bpf iter batching and lock_sock") is not
used for the UNIX domain socket.  It will require replacing the big lock
for the hash table with small locks for each hash list not to block other
processes.

Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: Andrii Nakryiko 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20210814015718.42704-2-kuniyu@amazon.co.jp

btf: Add BTF_ID_LIST_SINGLE macro

2020-09-21T22:00:40+00:00

Add a convenience macro that allows defining a BTF ID list with
a single item. This lets us cut down on repetitive macros.

Suggested-by: Andrii Nakryiko 
Signed-off-by: Lorenz Bauer 
Signed-off-by: Alexei Starovoitov 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/bpf/20200921121227.255763-4-lmb@cloudflare.com

bpf: Add BTF_SET_START/END macros

2020-08-25T22:37:41+00:00

Adding support to define sorted set of BTF ID values.

Following defines sorted set of BTF ID values:

  BTF_SET_START(btf_allowlist_d_path)
  BTF_ID(func, vfs_truncate)
  BTF_ID(func, vfs_fallocate)
  BTF_ID(func, dentry_open)
  BTF_ID(func, vfs_getattr)
  BTF_ID(func, filp_close)
  BTF_SET_END(btf_allowlist_d_path)

It defines following 'struct btf_id_set' variable to access
values and count:

  struct btf_id_set btf_allowlist_d_path;

Adding 'allowed' callback to struct bpf_func_proto, to allow
verifier the check on allowed callers.

Adding btf_id_set_contains function, which will be used by
allowed callbacks to verify the caller's BTF ID value is
within allowed set.

Also removing extra '\' in __BTF_ID_LIST macro.

Added BTF_SET_START_GLOBAL macro for global sets.

Signed-off-by: Jiri Olsa 
Signed-off-by: Alexei Starovoitov 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20200825192124.710397-10-jolsa@kernel.org

bpf: Make btf_sock_ids global

2020-07-21T20:26:26+00:00

tcp and udp bpf_iter can reuse some socket ids in
btf_sock_ids, so make it global.

I put the extern definition in btf_ids.h as a central
place so it can be easily discovered by developers.

Signed-off-by: Yonghong Song 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20200720163402.1393427-1-yhs@fb.com

bpf: Add BTF_ID_LIST_GLOBAL in btf_ids.h

2020-07-21T20:26:26+00:00

Existing BTF_ID_LIST used a local static variable
to store btf_ids. This patch provided a new macro
BTF_ID_LIST_GLOBAL to store btf_ids in a global
variable which can be shared among multiple files.

The existing BTF_ID_LIST is still retained.
Two reasons. First, BTF_ID_LIST is also used to build
btf_ids for helper arguments which typically
is an array of 5. Since typically different
helpers have different signature, it makes
little sense to share them. Second, some
current computed btf_ids are indeed local.
If later those btf_ids are shared between
different files, they can use BTF_ID_LIST_GLOBAL then.

Signed-off-by: Yonghong Song 
Signed-off-by: Alexei Starovoitov 
Acked-by: Jiri Olsa 
Link: https://lore.kernel.org/bpf/20200720163401.1393159-1-yhs@fb.com