bpf: Add kmem_cache iterator

The new "kmem_cache" iterator will traverse the list of slab caches
and call attached BPF programs for each entry. It should check the
argument (ctx.s) if it's NULL bef

bpf: Add kmem_cache iterator

The new "kmem_cache" iterator will traverse the list of slab caches
and call attached BPF programs for each entry. It should check the
argument (ctx.s) if it's NULL before using it.

Now the iteration grabs the slab_mutex only if it traverse the list and
releases the mutex when it runs the BPF program. The kmem_cache entry
is protected by a refcount during the execution.

Signed-off-by: Namhyung Kim <[email protected]>
Acked-by: Vlastimil Babka <[email protected]> #slab
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: Include linux/types.h for u32

Inclusion of the header linux/btf_ids.h relies on indirect inclusion of
the header linux/types.h. Including it directly on the top level helps
to avoid potential p

bpf: Include linux/types.h for u32

Inclusion of the header linux/btf_ids.h relies on indirect inclusion of
the header linux/types.h. Including it directly on the top level helps
to avoid potential problems if linux/types.h hasn't been included
before.

The main motivation to introduce this it is to avoid similar problems that
have shown up in the bpftool where GNU libc indirectly pulls
linux/types.h causing compile error of the form:

error: unknown type name 'u32'
u32 cnt;
^~~

The bpftool compile error was fixed in
62248b22d01e ("tools/resolve_btfids: fix build with musl libc").

Signed-off-by: Dmitrii Bundin <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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bpf: btf: Add BTF_KFUNCS_START/END macro pair

This macro pair is functionally equivalent to BTF_SET8_START/END, except
with BTF_SET8_KFUNCS flag set in the btf_id_set8 flags field. The next
commit w

bpf: btf: Add BTF_KFUNCS_START/END macro pair

This macro pair is functionally equivalent to BTF_SET8_START/END, except
with BTF_SET8_KFUNCS flag set in the btf_id_set8 flags field. The next
commit will codemod all kfunc set8s to this new variant such that all
kfuncs are tagged as such in .BTF_ids section.

Signed-off-by: Daniel Xu <[email protected]>
Link: https://lore.kernel.org/r/d536c57c7c2af428686853cc7396b7a44faa53b7.1706491398.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: btf: Support flags for BTF_SET8 sets

This commit adds support for flags on BTF_SET8s. struct btf_id_set8
already supported 32 bits worth of flags, but was only used for
alignment purposes befor

bpf: btf: Support flags for BTF_SET8 sets

This commit adds support for flags on BTF_SET8s. struct btf_id_set8
already supported 32 bits worth of flags, but was only used for
alignment purposes before.

We now use these bits to encode flags. The first use case is tagging
kfunc sets with a flag so that pahole can recognize which
BTF_ID_FLAGS(func, ..) are actual kfuncs.

Signed-off-by: Daniel Xu <[email protected]>
Link: https://lore.kernel.org/r/7bb152ec76d6c2c930daec88e995bf18484a5ebb.1706491398.git.dxu@dxuuu.xyz
Signed-off-by: Alexei Starovoitov <[email protected]>

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bpf: Fix BTF_ID symbol generation collision

Marcus and Satya reported an issue where BTF_ID macro generates same
symbol in separate objects and that breaks final vmlinux link.

ld.lld: error: ld-tem

bpf: Fix BTF_ID symbol generation collision

Marcus and Satya reported an issue where BTF_ID macro generates same
symbol in separate objects and that breaks final vmlinux link.

ld.lld: error: ld-temp.o <inline asm>:14577:1: symbol
'__BTF_ID__struct__cgroup__624' is already defined

This can be triggered under specific configs when __COUNTER__ happens to
be the same for the same symbol in two different translation units,
which is already quite unlikely to happen.

Add __LINE__ number suffix to make BTF_ID symbol more unique, which is
not a complete fix, but it would help for now and meanwhile we can work
on better solution as suggested by Andrii.

Cc: [email protected]
Reported-by: Satya Durga Srinivasu Prabhala <[email protected]>
Reported-by: Marcus Seyfarth <[email protected]>
Closes: https://github.com/ClangBuiltLinux/linux/issues/1913
Debugged-by: Nathan Chancellor <[email protected]>
Link: https://lore.kernel.org/bpf/CAEf4Bzb5KQ2_LmhN769ifMeSJaWfebccUasQOfQKaOd0nQ51tw@mail.gmail.com/
Signed-off-by: Jiri Olsa <[email protected]>
Signed-off-by: Nick Desaulniers <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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bpf: consider CONST_PTR_TO_MAP as trusted pointer to struct bpf_map

Add the BTF id of struct bpf_map to the reg2btf_ids array. This makes the
values of the CONST_PTR_TO_MAP type to be considered as

bpf: consider CONST_PTR_TO_MAP as trusted pointer to struct bpf_map

Add the BTF id of struct bpf_map to the reg2btf_ids array. This makes the
values of the CONST_PTR_TO_MAP type to be considered as trusted by kfuncs.
This, in turn, allows users to execute trusted kfuncs which accept `struct
bpf_map *` arguments from non-tracing programs.

While exporting the btf_bpf_map_id variable, save some bytes by defining
it as BTF_ID_LIST_GLOBAL_SINGLE (which is u32[1]) and not as BTF_ID_LIST
(which is u32[64]).

Signed-off-by: Anton Protopopov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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bpf: Increase size of BTF_ID_LIST without CONFIG_DEBUG_INFO_BTF again

After commit 66e3a13e7c2c ("bpf: Add bpf_dynptr_slice and bpf_dynptr_slice_rdwr"),
clang builds without CONFIG_DEBUG_INFO_BTF wa

bpf: Increase size of BTF_ID_LIST without CONFIG_DEBUG_INFO_BTF again

After commit 66e3a13e7c2c ("bpf: Add bpf_dynptr_slice and bpf_dynptr_slice_rdwr"),
clang builds without CONFIG_DEBUG_INFO_BTF warn:

kernel/bpf/verifier.c:10298:24: warning: array index 16 is past the end of the array (that has type 'u32[16]' (aka 'unsigned int[16]')) [-Warray-bounds]
meta.func_id == special_kfunc_list[KF_bpf_dynptr_slice_rdwr]) {
^ ~~~~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/verifier.c:9150:1: note: array 'special_kfunc_list' declared here
BTF_ID_LIST(special_kfunc_list)
^
include/linux/btf_ids.h:207:27: note: expanded from macro 'BTF_ID_LIST'
#define BTF_ID_LIST(name) static u32 __maybe_unused name[16];
^
1 warning generated.

A warning of this nature was previously addressed by
commit beb3d47d1d3d ("bpf: Fix a BTF_ID_LIST bug with CONFIG_DEBUG_INFO_BTF not set")
but there have been new kfuncs added since then.

Quadruple the size of the CONFIG_DEBUG_INFO_BTF=n definition so that
this problem is unlikely to show up for some time.

Link: https://github.com/ClangBuiltLinux/linux/issues/1810
Signed-off-by: Nathan Chancellor <[email protected]>
Reviewed-by: Tom Rix <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

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bpf: Fix a compilation failure with clang lto build

When building the kernel with clang lto (CONFIG_LTO_CLANG_FULL=y), the
following compilation error will appear:

$ make LLVM=1 LLVM_IAS=1 -j
.

bpf: Fix a compilation failure with clang lto build

When building the kernel with clang lto (CONFIG_LTO_CLANG_FULL=y), the
following compilation error will appear:

$ make LLVM=1 LLVM_IAS=1 -j
...
ld.lld: error: ld-temp.o <inline asm>:26889:1: symbol 'cgroup_storage_map_btf_ids' is already defined
cgroup_storage_map_btf_ids:;
^
make[1]: *** [/.../bpf-next/scripts/Makefile.vmlinux_o:61: vmlinux.o] Error 1

In local_storage.c, we have
BTF_ID_LIST_SINGLE(cgroup_storage_map_btf_ids, struct, bpf_local_storage_map)
Commit c4bcfb38a95e ("bpf: Implement cgroup storage available to
non-cgroup-attached bpf progs") added the above identical BTF_ID_LIST_SINGLE
definition in bpf_cgrp_storage.c. With duplicated definitions, llvm linker
complains with lto build.

Also, extracting btf_id of 'struct bpf_local_storage_map' is defined four times
for sk, inode, task and cgrp local storages. Let us define a single global one
with a different name than cgroup_storage_map_btf_ids, which also fixed
the lto compilation error.

Fixes: c4bcfb38a95e ("bpf: Implement cgroup storage available to non-cgroup-attached bpf progs")
Signed-off-by: Yonghong Song <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

show more ...

bpf: Fix a BTF_ID_LIST bug with CONFIG_DEBUG_INFO_BTF not set

With CONFIG_DEBUG_INFO_BTF not set, we hit the following compilation error,
/.../kernel/bpf/verifier.c:8196:23: error: array index 6 i

bpf: Fix a BTF_ID_LIST bug with CONFIG_DEBUG_INFO_BTF not set

With CONFIG_DEBUG_INFO_BTF not set, we hit the following compilation error,
/.../kernel/bpf/verifier.c:8196:23: error: array index 6 is past the end of the array
(that has type 'u32[5]' (aka 'unsigned int[5]')) [-Werror,-Warray-bounds]
if (meta->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx])
^ ~~~~~~~~~~~~~~~~~~~~~~~
/.../kernel/bpf/verifier.c:8174:1: note: array 'special_kfunc_list' declared here
BTF_ID_LIST(special_kfunc_list)
^
/.../include/linux/btf_ids.h:207:27: note: expanded from macro 'BTF_ID_LIST'
#define BTF_ID_LIST(name) static u32 __maybe_unused name[5];
^
/.../kernel/bpf/verifier.c:8443:19: error: array index 5 is past the end of the array
(that has type 'u32[5]' (aka 'unsigned int[5]')) [-Werror,-Warray-bounds]
btf_id == special_kfunc_list[KF_bpf_list_pop_back];
^ ~~~~~~~~~~~~~~~~~~~~
/.../kernel/bpf/verifier.c:8174:1: note: array 'special_kfunc_list' declared here
BTF_ID_LIST(special_kfunc_list)
^
/.../include/linux/btf_ids.h:207:27: note: expanded from macro 'BTF_ID_LIST'
#define BTF_ID_LIST(name) static u32 __maybe_unused name[5];
...

Fix the problem by increase the size of BTF_ID_LIST to 16 to avoid compilation error
and also prevent potentially unintended issue due to out-of-bound access.

Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Reported-by: Nathan Chancellor <[email protected]>
Signed-off-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: Make struct cgroup btf id global

Make struct cgroup btf id global so later patch can reuse
the same btf id.

Acked-by: David Vernet <[email protected]>
Signed-off-by: Yonghong Song <[email protected]

bpf: Make struct cgroup btf id global

Make struct cgroup btf id global so later patch can reuse
the same btf id.

Acked-by: David Vernet <[email protected]>
Signed-off-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: Fix build error in case of !CONFIG_DEBUG_INFO_BTF

BTF_ID_FLAGS macro needs to be able to take 0 or 1 args, so make it a
variable argument. BTF_SET8_END is incorrect, it should just be empty.

R

bpf: Fix build error in case of !CONFIG_DEBUG_INFO_BTF

BTF_ID_FLAGS macro needs to be able to take 0 or 1 args, so make it a
variable argument. BTF_SET8_END is incorrect, it should just be empty.

Reported-by: kernel test robot <[email protected]>
Fixes: ab21d6063c01 ("bpf: Introduce 8-byte BTF set")
Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: Introduce 8-byte BTF set

Introduce support for defining flags for kfuncs using a new set of
macros, BTF_SET8_START/BTF_SET8_END, which define a set which contains
8 byte elements (each of which

bpf: Introduce 8-byte BTF set

Introduce support for defining flags for kfuncs using a new set of
macros, BTF_SET8_START/BTF_SET8_END, which define a set which contains
8 byte elements (each of which consists of a pair of BTF ID and flags),
using a new BTF_ID_FLAGS macro.

This will be used to tag kfuncs registered for a certain program type
as acquire, release, sleepable, ret_null, etc. without having to create
more and more sets which was proving to be an unscalable solution.

Now, when looking up whether a kfunc is allowed for a certain program,
we can also obtain its kfunc flags in the same call and avoid further
lookups.

The resolve_btfids change is split into a separate patch.

Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: per-cgroup lsm flavor

Allow attaching to lsm hooks in the cgroup context.

Attaching to per-cgroup LSM works exactly like attaching
to other per-cgroup hooks. New BPF_LSM_CGROUP is added
to tri

bpf: per-cgroup lsm flavor

Allow attaching to lsm hooks in the cgroup context.

Attaching to per-cgroup LSM works exactly like attaching
to other per-cgroup hooks. New BPF_LSM_CGROUP is added
to trigger new mode; the actual lsm hook we attach to is
signaled via existing attach_btf_id.

For the hooks that have 'struct socket' or 'struct sock' as its first
argument, we use the cgroup associated with that socket. For the rest,
we use 'current' cgroup (this is all on default hierarchy == v2 only).
Note that for some hooks that work on 'struct sock' we still
take the cgroup from 'current' because some of them work on the socket
that hasn't been properly initialized yet.

Behind the scenes, we allocate a shim program that is attached
to the trampoline and runs cgroup effective BPF programs array.
This shim has some rudimentary ref counting and can be shared
between several programs attaching to the same lsm hook from
different cgroups.

Note that this patch bloats cgroup size because we add 211
cgroup_bpf_attach_type(s) for simplicity sake. This will be
addressed in the subsequent patch.

Also note that we only add non-sleepable flavor for now. To enable
sleepable use-cases, bpf_prog_run_array_cg has to grab trace rcu,
shim programs have to be freed via trace rcu, cgroup_bpf.effective
should be also trace-rcu-managed + maybe some other changes that
I'm not aware of.

Reviewed-by: Martin KaFai Lau <[email protected]>
Signed-off-by: Stanislav Fomichev <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: Add bpf_skc_to_mptcp_sock_proto

This patch implements a new struct bpf_func_proto, named
bpf_skc_to_mptcp_sock_proto. Define a new bpf_id BTF_SOCK_TYPE_MPTCP,
and a new helper bpf_skc_to_mptcp_

bpf: Add bpf_skc_to_mptcp_sock_proto

This patch implements a new struct bpf_func_proto, named
bpf_skc_to_mptcp_sock_proto. Define a new bpf_id BTF_SOCK_TYPE_MPTCP,
and a new helper bpf_skc_to_mptcp_sock(), which invokes another new
helper bpf_mptcp_sock_from_subflow() in net/mptcp/bpf.c to get struct
mptcp_sock from a given subflow socket.

v2: Emit BTF type, add func_id checks in verifier.c and bpf_trace.c,
remove build check for CONFIG_BPF_JIT
v5: Drop EXPORT_SYMBOL (Martin)

Co-developed-by: Nicolas Rybowski <[email protected]>
Co-developed-by: Matthieu Baerts <[email protected]>
Signed-off-by: Nicolas Rybowski <[email protected]>
Signed-off-by: Matthieu Baerts <[email protected]>
Signed-off-by: Geliang Tang <[email protected]>
Signed-off-by: Mat Martineau <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

show more ...

bpf: Populate kfunc BTF ID sets in struct btf

This patch prepares the kernel to support putting all kinds of kfunc BTF
ID sets in the struct btf itself. The various kernel subsystems will
make regis

bpf: Populate kfunc BTF ID sets in struct btf

This patch prepares the kernel to support putting all kinds of kfunc BTF
ID sets in the struct btf itself. The various kernel subsystems will
make register_btf_kfunc_id_set call in the initcalls (for built-in code
and modules).

The 'hook' is one of the many program types, e.g. XDP and TC/SCHED_CLS,
STRUCT_OPS, and 'types' are check (allowed or not), acquire, release,
and ret_null (with PTR_TO_BTF_ID_OR_NULL return type).

A maximum of BTF_KFUNC_SET_MAX_CNT (32) kfunc BTF IDs are permitted in a
set of certain hook and type for vmlinux sets, since they are allocated
on demand, and otherwise set as NULL. Module sets can only be registered
once per hook and type, hence they are directly assigned.

A new btf_kfunc_id_set_contains function is exposed for use in verifier,
this new method is faster than the existing list searching method, and
is also automatic. It also lets other code not care whether the set is
unallocated or not.

Note that module code can only do single register_btf_kfunc_id_set call
per hook. This is why sorting is only done for in-kernel vmlinux sets,
because there might be multiple sets for the same hook and type that
must be concatenated, hence sorting them is required to ensure bsearch
in btf_id_set_contains continues to work correctly.

Next commit will update the kernel users to make use of this
infrastructure.

Finally, add __maybe_unused annotation for BTF ID macros for the
!CONFIG_DEBUG_INFO_BTF case, so that they don't produce warnings during
build time.

The previous patch is also needed to provide synchronization against
initialization for module BTF's kfunc_set_tab introduced here, as
described below:

The kfunc_set_tab pointer in struct btf is write-once (if we consider
the registration phase (comprised of multiple register_btf_kfunc_id_set
calls) as a single operation). In this sense, once it has been fully
prepared, it isn't modified, only used for lookup (from the verifier
context).

For btf_vmlinux, it is initialized fully during the do_initcalls phase,
which happens fairly early in the boot process, before any processes are
present. This also eliminates the possibility of bpf_check being called
at that point, thus relieving us of ensuring any synchronization between
the registration and lookup function (btf_kfunc_id_set_contains).

However, the case for module BTF is a bit tricky. The BTF is parsed,
prepared, and published from the MODULE_STATE_COMING notifier callback.
After this, the module initcalls are invoked, where our registration
function will be called to populate the kfunc_set_tab for module BTF.

At this point, BTF may be available to userspace while its corresponding
module is still intializing. A BTF fd can then be passed to verifier
using bpf syscall (e.g. for kfunc call insn).

Hence, there is a race window where verifier may concurrently try to
lookup the kfunc_set_tab. To prevent this race, we must ensure the
operations are serialized, or waiting for the __init functions to
complete.

In the earlier registration API, this race was alleviated as verifier
bpf_check_mod_kfunc_call didn't find the kfunc BTF ID until it was added
by the registration function (called usually at the end of module __init
function after all module resources have been initialized). If the
verifier made the check_kfunc_call before kfunc BTF ID was added to the
list, it would fail verification (saying call isn't allowed). The
access to list was protected using a mutex.

Now, it would still fail verification, but for a different reason
(returning ENXIO due to the failed btf_try_get_module call in
add_kfunc_call), because if the __init call is in progress the module
will be in the middle of MODULE_STATE_COMING -> MODULE_STATE_LIVE
transition, and the BTF_MODULE_LIVE flag for btf_module instance will
not be set, so the btf_try_get_module call will fail.

Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

show more ...

bpf: Introduce btf_tracing_ids

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_

bpf: Introduce btf_tracing_ids

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 <[email protected]>
Signed-off-by: Song Liu <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

show more ...

bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs

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

bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs

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:
<TASK>
__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
</TASK>

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: [email protected]
Reported-by: Eric Dumazet <[email protected]>
Suggested-by: Eric Dumazet <[email protected]>
Signed-off-by: Song Liu <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

show more ...

bpf: Fix bpf-next builds without CONFIG_BPF_EVENTS

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'

bpf: Fix bpf-next builds without CONFIG_BPF_EVENTS

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 <[email protected]>
Signed-off-by: Daniel Xu <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/05d94748d9f4b3eecedc4fddd6875418a396e23c.1629942444.git.dxu@dxuuu.xyz

show more ...

bpf: Consolidate task_struct BTF_ID declarations

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

Signed-off-by: Daniel Xu <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link

bpf: Consolidate task_struct BTF_ID declarations

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

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

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bpf: Add BTF_ID_LIST_GLOBAL_SINGLE macro

Same as BTF_ID_LIST_SINGLE macro except defines a global ID.

Signed-off-by: Daniel Xu <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Lin

bpf: Add BTF_ID_LIST_GLOBAL_SINGLE macro

Same as BTF_ID_LIST_SINGLE macro except defines a global ID.

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

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

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

Currently, the batch optimisation introduced for the TCP iterator in

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

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 <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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btf: Add BTF_ID_LIST_SINGLE macro

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 <andriin@f

btf: Add BTF_ID_LIST_SINGLE macro

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 <[email protected]>
Signed-off-by: Lorenz Bauer <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Martin KaFai Lau <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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bpf: Add BTF_SET_START/END macros

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_trun

bpf: Add BTF_SET_START/END macros

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 <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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bpf: Make btf_sock_ids global

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 disc

bpf: Make btf_sock_ids global

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 <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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bpf: Add BTF_ID_LIST_GLOBAL in btf_ids.h

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

bpf: Add BTF_ID_LIST_GLOBAL in btf_ids.h

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 <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

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