This patch adds a test exercising logic that was fixed / improved in
the previous patch in the series, as well as general sanity checking for
jit's PROBE_MEM logic which should've been unaffected by the previous
patch.
The added verifier test does the following:
* Acquire a referenced kptr to struct prog_test_ref_kfunc using
existing net/bpf/test_run.c kfunc
* Helper returns ptr to a specific prog_test_ref_kfunc whose first
two fields - both ints - have been prepopulated w/ vals 42 and
108, respectively
* kptr_xchg the acquired ptr into an arraymap
* Do a direct map_value load of the just-added ptr
* Goal of all this setup is to get an unreferenced kptr pointing to
struct with ints of known value, which is the result of this step
* Using unreferenced kptr obtained in previous step, do loads of
prog_test_ref_kfunc.a (offset 0) and .b (offset 4)
* Then incr the kptr by 8 and load prog_test_ref_kfunc.a again (this
time at offset -8)
* Add all the loaded ints together and return
Before the PROBE_MEM fixes in previous patch, the loads at offset 0 and
4 would succeed, while the load at offset -8 would incorrectly fail
runtime check emitted by the JIT and 0 out dst reg as a result. This
confirmed by retval of 150 for this test before previous patch - since
second .a read is 0'd out - and a retval of 192 with the fixed logic.
The test exercises the two optimizations to fixed logic added in last
patch as well:
* First load, with insn "r8 = *(u32 *)(r9 + 0)" exercises "insn->off
is 0, no need to add / sub from src_reg" optimization
* Third load, with insn "r9 = *(u32 *)(r9 - 8)" exercises "src_reg ==
dst_reg, no need to restore src_reg after load" optimization
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221216214319.3408356-2-davemarchevsky@fb.com
This adds a simple test for inserting an XDP program into a cpumap that is
"owned" by an XDP program that was loaded as PROG_TYPE_EXT (as libxdp
does). Prior to the kernel fix this would fail because the map type
ownership would be set to PROG_TYPE_EXT instead of being resolved to
PROG_TYPE_XDP.
v5:
- Fix a few nits from Andrii, add his ACK
v4:
- Use skeletons for selftest
v3:
- Update comment to better explain the cause
- Add Yonghong's ACK
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20221214230254.790066-2-toke@redhat.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
The original support for bpf_user_ringbuf_drain callbacks simply
short-circuited checks for the dynptr state, allowing users to pass
PTR_TO_DYNPTR (now CONST_PTR_TO_DYNPTR) to helpers that initialize a
dynptr. This bug would have also surfaced with other dynptr helpers in
the future that changed dynptr view or modified it in some way.
Include test cases for all cases, i.e. both bpf_dynptr_from_mem and
bpf_ringbuf_reserve_dynptr, and ensure verifier rejects both of them.
Without the fix, both of these programs load and pass verification.
While at it, remove sys_nanosleep target from failure cases' SEC
definition, as there is no such tracepoint.
Acked-by: David Vernet <void@manifault.com>
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221207204141.308952-8-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Recently, user ringbuf support introduced a PTR_TO_DYNPTR register type
for use in callback state, because in case of user ringbuf helpers,
there is no dynptr on the stack that is passed into the callback. To
reflect such a state, a special register type was created.
However, some checks have been bypassed incorrectly during the addition
of this feature. First, for arg_type with MEM_UNINIT flag which
initialize a dynptr, they must be rejected for such register type.
Secondly, in the future, there are plans to add dynptr helpers that
operate on the dynptr itself and may change its offset and other
properties.
In all of these cases, PTR_TO_DYNPTR shouldn't be allowed to be passed
to such helpers, however the current code simply returns 0.
The rejection for helpers that release the dynptr is already handled.
For fixing this, we take a step back and rework existing code in a way
that will allow fitting in all classes of helpers and have a coherent
model for dealing with the variety of use cases in which dynptr is used.
First, for ARG_PTR_TO_DYNPTR, it can either be set alone or together
with a DYNPTR_TYPE_* constant that denotes the only type it accepts.
Next, helpers which initialize a dynptr use MEM_UNINIT to indicate this
fact. To make the distinction clear, use MEM_RDONLY flag to indicate
that the helper only operates on the memory pointed to by the dynptr,
not the dynptr itself. In C parlance, it would be equivalent to taking
the dynptr as a point to const argument.
When either of these flags are not present, the helper is allowed to
mutate both the dynptr itself and also the memory it points to.
Currently, the read only status of the memory is not tracked in the
dynptr, but it would be trivial to add this support inside dynptr state
of the register.
With these changes and renaming PTR_TO_DYNPTR to CONST_PTR_TO_DYNPTR to
better reflect its usage, it can no longer be passed to helpers that
initialize a dynptr, i.e. bpf_dynptr_from_mem, bpf_ringbuf_reserve_dynptr.
A note to reviewers is that in code that does mark_stack_slots_dynptr,
and unmark_stack_slots_dynptr, we implicitly rely on the fact that
PTR_TO_STACK reg is the only case that can reach that code path, as one
cannot pass CONST_PTR_TO_DYNPTR to helpers that don't set MEM_RDONLY. In
both cases such helpers won't be setting that flag.
The next patch will add a couple of selftest cases to make sure this
doesn't break.
Fixes: 2057156738 ("bpf: Add bpf_user_ringbuf_drain() helper")
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221207204141.308952-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
ARG_PTR_TO_DYNPTR is akin to ARG_PTR_TO_TIMER, ARG_PTR_TO_KPTR, where
the underlying register type is subjected to more special checks to
determine the type of object represented by the pointer and its state
consistency.
Move dynptr checks to their own 'process_dynptr_func' function so that
is consistent and in-line with existing code. This also makes it easier
to reuse this code for kfunc handling.
Then, reuse this consolidated function in kfunc dynptr handling too.
Note that for kfuncs, the arg_type constraint of DYNPTR_TYPE_LOCAL has
been lifted.
Acked-by: David Vernet <void@manifault.com>
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221207204141.308952-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Convert big chunks of dynptr and map_kptr subtests to use generic
verification_tester. They are switched from using manually maintained
tables of test cases, specifying program name and expected error
verifier message, to btf_decl_tag-based annotations directly on
corresponding BPF programs: __failure to specify that BPF program is
expected to fail verification, and __msg() to specify expected log
message.
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221207201648.2990661-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Test the xfrm_info kfunc helpers.
The test setup creates three name spaces - NS0, NS1, NS2.
XFRM tunnels are setup between NS0 and the two other NSs.
The kfunc helpers are used to steer traffic from NS0 to the other
NSs based on a userspace populated bpf global variable and validate
that the return traffic had arrived from the desired NS.
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20221203084659.1837829-5-eyal.birger@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Add three tests for cgrp local storage support for sleepable progs.
Two tests can load and run properly, one for cgroup_iter, another
for passing current->cgroups->dfl_cgrp to bpf_cgrp_storage_get()
helper. One test has bpf_rcu_read_lock() and failed to load.
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221201050449.2785613-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Martin mentioned that the verifier cannot assume arguments from
LSM hook sk_alloc_security being trusted since after the hook
is called, the sk ref_count is set to 1. This will overwrite
the ref_count changed by the bpf program and may cause ref_count
underflow later on.
I then further checked some other hooks. For example,
for bpf_lsm_file_alloc() hook in fs/file_table.c,
f->f_cred = get_cred(cred);
error = security_file_alloc(f);
if (unlikely(error)) {
file_free_rcu(&f->f_rcuhead);
return ERR_PTR(error);
}
atomic_long_set(&f->f_count, 1);
The input parameter 'f' to security_file_alloc() cannot be trusted
as well.
Specifically, I investiaged bpf_map/bpf_prog/file/sk/task alloc/free
lsm hooks. Except bpf_map_alloc and task_alloc, arguments for all other
hooks should not be considered as trusted. This may not be a complete
list, but it covers common usage for sk and task.
Fixes: 3f00c52393 ("bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs")
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203204954.2043348-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch removes the need to pin prog when attaching to tc ingress
in the btf_skc_cls_ingress test. Instead, directly use the
bpf_tc_hook_create() and bpf_tc_attach(). The qdisc clsact
will go away together with the netns, so no need to
bpf_tc_hook_destroy().
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-8-martin.lau@linux.dev
After removing the mount/umount dance from {open,close}_netns()
in the pervious patch, "serial_" can be removed from
the tests using {open,close}_netns().
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-7-martin.lau@linux.dev
This patch removes the need to pin prog in the remaining tests in
tc_redirect.c by directly using the bpf_tc_hook_create() and
bpf_tc_attach(). The clsact qdisc will go away together with
the test netns, so no need to do bpf_tc_hook_destroy().
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-5-martin.lau@linux.dev
This patch removes the need to pin prog in the tc_redirect_peer_l3
test by directly using the bpf_tc_hook_create() and bpf_tc_attach().
The clsact qdisc will go away together with the test netns, so
no need to do bpf_tc_hook_destroy().
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-4-martin.lau@linux.dev
This patch removes the need to pin prog in the tc_redirect_dtime
test by directly using the bpf_tc_hook_create() and bpf_tc_attach().
The clsact qdisc will go away together with the test netns, so
no need to do bpf_tc_hook_destroy().
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-3-martin.lau@linux.dev
When switching netns, the setns_by_fd() is doing dances in mount/umounting
the /sys directories. One reason is the tc_redirect.c test is depending
on the /sys/net/class/*/ifindex instead of using the if_nametoindex().
if_nametoindex() uses ioctl() to get the ifindex.
This patch is to move all /sys/net/class/*/ifindex usages to
if_nametoindex(). The current code checks ifindex >= 0 which is
incorrect. ifindex > 0 should be checked instead. This patch also
stores ifindex_veth_src and ifindex_veth_dst since the latter patch
will need them.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221129070900.3142427-2-martin.lau@linux.dev
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Daniel Borkmann says:
====================
bpf-next 2022-11-25
We've added 101 non-merge commits during the last 11 day(s) which contain
a total of 109 files changed, 8827 insertions(+), 1129 deletions(-).
The main changes are:
1) Support for user defined BPF objects: the use case is to allocate own
objects, build own object hierarchies and use the building blocks to
build own data structures flexibly, for example, linked lists in BPF,
from Kumar Kartikeya Dwivedi.
2) Add bpf_rcu_read_{,un}lock() support for sleepable programs,
from Yonghong Song.
3) Add support storing struct task_struct objects as kptrs in maps,
from David Vernet.
4) Batch of BPF map documentation improvements, from Maryam Tahhan
and Donald Hunter.
5) Improve BPF verifier to propagate nullness information for branches
of register to register comparisons, from Eduard Zingerman.
6) Fix cgroup BPF iter infra to hold reference on the start cgroup,
from Hou Tao.
7) Fix BPF verifier to not mark fentry/fexit program arguments as trusted
given it is not the case for them, from Alexei Starovoitov.
8) Improve BPF verifier's realloc handling to better play along with dynamic
runtime analysis tools like KASAN and friends, from Kees Cook.
9) Remove legacy libbpf mode support from bpftool,
from Sahid Orentino Ferdjaoui.
10) Rework zero-len skb redirection checks to avoid potentially breaking
existing BPF test infra users, from Stanislav Fomichev.
11) Two small refactorings which are independent and have been split out
of the XDP queueing RFC series, from Toke Høiland-Jørgensen.
12) Fix a memory leak in LSM cgroup BPF selftest, from Wang Yufen.
13) Documentation on how to run BPF CI without patch submission,
from Daniel Müller.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
Link: https://lore.kernel.org/r/20221125012450.441-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a few positive/negative tests to test bpf_rcu_read_lock()
and its corresponding verifier support. The new test will fail
on s390x and aarch64, so an entry is added to each of their
respective deny lists.
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221124053222.2374650-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add some selftest testcases that validate the expected behavior of the
bpf_task_from_pid() kfunc that was added in the prior patch.
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221122145300.251210-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_cgroup_ancestor() allows BPF programs to access the ancestor of a
struct cgroup *. This patch adds selftests that validate its expected
behavior.
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221122055458.173143-5-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds a selftest suite to validate the cgroup kfuncs that were
added in the prior patch.
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221122055458.173143-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Currently LLVM fails to recognize .data.* as data section and defaults to .text
section. Later BPF backend tries to emit 4-byte NOP instruction which doesn't
exist in BPF ISA and aborts.
The fix for LLVM is pending:
https://reviews.llvm.org/D138477
While waiting for the fix lets workaround the linked_list test case
by using .bss.* prefix which is properly recognized by LLVM as BSS section.
Fix libbpf to support .bss. prefix and adjust tests.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
LWT_XMIT to test L3 case, TC to test L2 case.
v2:
- s/veth_ifindex/ipip_ifindex/ in two places (Martin)
- add comment about which condition triggers the rejection (Martin)
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20221121180340.1983627-2-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Alexei hit another rcu warnings because of this test.
Making test_bench_attach serial so it does not disrupts
other tests during parallel tests run.
While this change is not the fix, it should be less likely
to hit it with this test being executed serially.
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20221116100228.2064612-2-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Alexei hit following rcu warning when running prog_test -j.
[ 128.049567] WARNING: suspicious RCU usage
[ 128.049569] 6.1.0-rc2 #912 Tainted: G O
...
[ 128.050944] kprobe_multi_link_handler+0x6c/0x1d0
[ 128.050947] ? kprobe_multi_link_handler+0x42/0x1d0
[ 128.050950] ? __cpuidle_text_start+0x8/0x8
[ 128.050952] ? __cpuidle_text_start+0x8/0x8
[ 128.050958] fprobe_handler.part.1+0xac/0x150
[ 128.050964] 0xffffffffa02130c8
[ 128.050991] ? default_idle+0x5/0x20
[ 128.050998] default_idle+0x5/0x20
It's caused by bench test attaching kprobe_multi link to default_idle
function, which is not executed in rcu safe context so the kprobe
handler on top of it will trigger the rcu warning.
Filtering out default_idle function from the bench test.
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20221116100228.2064612-1-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test closes both iterator link fd and cgroup fd, and removes the
cgroup file to make a dead cgroup before reading from cgroup iterator.
It also uses kern_sync_rcu() and usleep() to wait for the release of
start cgroup. If the start cgroup is not pinned by cgroup iterator,
reading from iterator fd will trigger use-after-free.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20221121073440.1828292-4-houtao@huaweicloud.com
Three tests are added. One is from John Fastabend ({1]) which tests
tracing style access for xdp program from the kernel ctx.
Another is a tc test to test both kernel ctx tracing style access
and explicit non-ctx type cast. The third one is for negative tests
including two tests, a tp_bpf test where the bpf_rdonly_cast()
returns a untrusted ptr which cannot be used as helper argument,
and a tracepoint test where the kernel ctx is a u64.
Also added the test to DENYLIST.s390x since s390 does not currently
support calling kernel functions in JIT mode.
[1] https://lore.kernel.org/bpf/20221109215242.1279993-1-john.fastabend@gmail.com/
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221120195442.3114844-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
A previous change added a series of kfuncs for storing struct
task_struct objects as referenced kptrs. This patch adds a new
task_kfunc test suite for validating their expected behavior.
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221120051004.3605026-5-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Instead of adding the whole test to DENYLIST.s390x, which also has
success test cases that should be run, just skip over failure test
cases in case the JIT does not support kfuncs.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118185938.2139616-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Preparing the metadata for bpf_list_head involves a complicated parsing
step and type resolution for the contained value. Ensure that corner
cases are tested against and invalid specifications in source are duly
rejected. Also include tests for incorrect ownership relationships in
the BTF.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-24-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Include various tests covering the success and failure cases. Also, run
the success cases at runtime to verify correctness of linked list
manipulation routines, in addition to ensuring successful verification.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-23-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
First, ensure that whenever a bpf_spin_lock is present in an allocation,
the reg->id is preserved. This won't be true for global variables
however, since they have a single map value per map, hence the verifier
harcodes it to 0 (so that multiple pseudo ldimm64 insns can yield the
same lock object per map at a given offset).
Next, add test cases for all possible combinations (kptr, global, map
value, inner map value). Since we lifted restriction on locking in inner
maps, also add test cases for them. Currently, each lookup into an inner
map gets a fresh reg->id, so even if the reg->map_ptr is same, they will
be treated as separate allocations and the incorrect unlock pairing will
be rejected.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-22-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make updates in preparation for adding more test cases to this selftest:
- Convert from CHECK_ to ASSERT macros.
- Use BPF skeleton
- Fix typo sping -> spin
- Rename spinlock.c -> spin_lock.c
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-21-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
As we continue to add more features, argument types, kfunc flags, and
different extensions to kfuncs, the code to verify the correctness of
the kfunc prototype wrt the passed in registers has become ad-hoc and
ugly to read. To make life easier, and make a very clear split between
different stages of argument processing, move all the code into
verifier.c and refactor into easier to read helpers and functions.
This also makes sharing code within the verifier easier with kfunc
argument processing. This will be more and more useful in later patches
as we are now moving to implement very core BPF helpers as kfuncs, to
keep them experimental before baking into UAPI.
Remove all kfunc related bits now from btf_check_func_arg_match, as
users have been converted away to refactored kfunc argument handling.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-12-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
kmemleak reports this issue:
unreferenced object 0xffff88810b7835c0 (size 32):
comm "test_progs", pid 270, jiffies 4294969007 (age 1621.315s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
03 00 00 00 03 00 00 00 0f 00 00 00 00 00 00 00 ................
backtrace:
[<00000000376cdeab>] kmalloc_trace+0x27/0x110
[<000000003bcdb3b6>] selinux_sk_alloc_security+0x66/0x110
[<000000003959008f>] security_sk_alloc+0x47/0x80
[<00000000e7bc6668>] sk_prot_alloc+0xbd/0x1a0
[<0000000002d6343a>] sk_alloc+0x3b/0x940
[<000000009812a46d>] unix_create1+0x8f/0x3d0
[<000000005ed0976b>] unix_create+0xa1/0x150
[<0000000086a1d27f>] __sock_create+0x233/0x4a0
[<00000000cffe3a73>] __sys_socket_create.part.0+0xaa/0x110
[<0000000007c63f20>] __sys_socket+0x49/0xf0
[<00000000b08753c8>] __x64_sys_socket+0x42/0x50
[<00000000b56e26b3>] do_syscall_64+0x3b/0x90
[<000000009b4871b8>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
The issue occurs in the following scenarios:
unix_create1()
sk_alloc()
sk_prot_alloc()
security_sk_alloc()
call_int_hook()
hlist_for_each_entry()
entry1->hook.sk_alloc_security
<-- selinux_sk_alloc_security() succeeded,
<-- sk->security alloced here.
entry2->hook.sk_alloc_security
<-- bpf_lsm_sk_alloc_security() failed
goto out_free;
... <-- the sk->security not freed, memleak
The core problem is that the LSM is not yet fully stacked (work is
actively going on in this space) which means that some LSM hooks do
not support multiple LSMs at the same time. To fix, skip the
"EPERM" test when it runs in the environments that already have
non-bpf lsms installed
Fixes: dca85aac88 ("selftests/bpf: lsm_cgroup functional test")
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Cc: Stanislav Fomichev <sdf@google.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/1668482980-16163-1-git-send-email-wangyufen@huawei.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Currently, verifier uses MEM_ALLOC type tag to specially tag memory
returned from bpf_ringbuf_reserve helper. However, this is currently
only used for this purpose and there is an implicit assumption that it
only refers to ringbuf memory (e.g. the check for ARG_PTR_TO_ALLOC_MEM
in check_func_arg_reg_off).
Hence, rename MEM_ALLOC to MEM_RINGBUF to indicate this special
relationship and instead open the use of MEM_ALLOC for more generic
allocations made for user types.
Also, since ARG_PTR_TO_ALLOC_MEM_OR_NULL is unused, simply drop it.
Finally, update selftests using 'alloc_' verifier string to 'ringbuf_'.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221114191547.1694267-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch tests reading the skops->skb_hwtstamp field.
A local test was also done such that the shinfo hwtstamp was temporary
set to a non zero value in the kernel bpf_skops_parse_hdr()
and the same value can be read by the skops test.
An adjustment is needed to the btf_dump selftest because
the changes in the 'struct bpf_sock_ops'.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221107230420.4192307-4-martin.lau@linux.dev
This patch fixes the incorrect ASSERT test in tcp_hdr_options during
the CHECK to ASSERT macro cleanup.
Fixes: 3082f8cd4b ("selftests/bpf: Convert tcp_hdr_options test to ASSERT_* macros")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Wang Yufen <wangyufen@huawei.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221107230420.4192307-3-martin.lau@linux.dev
This commit tests previous fix of bpf_probe_read_kernel_str().
The BPF helper bpf_probe_read_kernel_str should return -EFAULT when
given a bad source pointer and the target buffer should only be modified
to make the string NULL terminated.
bpf_probe_read_kernel_str() was previously inserting a NULL before the
beginning of the dst buffer. This test should ensure that the
implementation stays correct for now on.
Without the fix, this test will fail as follows:
$ cd tools/testing/selftests/bpf
$ make
$ sudo ./test_progs --name=varlen
...
test_varlen:FAIL:check got 0 != exp 66
Signed-off-by: Alban Crequy <albancrequy@linux.microsoft.com>
Signed-off-by: Francis Laniel <flaniel@linux.microsoft.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221110085614.111213-3-albancrequy@linux.microsoft.com
Changes v1 to v2:
- add ack tag
- fix my email
- rebase on bpf tree and tag for bpf tree
Tests to verify the following behavior of `btf_dedup_resolve_fwds`:
- remapping for struct forward declarations;
- remapping for union forward declarations;
- no remapping if forward declaration kind does not match similarly
named struct or union declaration;
- no remapping if forward declaration name is ambiguous;
- base ids are considered for fwd resolution in split btf scenario.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20221109142611.879983-4-eddyz87@gmail.com
An update for libbpf's hashmap interface from void* -> void* to a
polymorphic one, allowing both long and void* keys and values.
This simplifies many use cases in libbpf as hashmaps there are mostly
integer to integer.
Perf copies hashmap implementation from libbpf and has to be
updated as well.
Changes to libbpf, selftests/bpf and perf are packed as a single
commit to avoid compilation issues with any future bisect.
Polymorphic interface is acheived by hiding hashmap interface
functions behind auxiliary macros that take care of necessary
type casts, for example:
#define hashmap_cast_ptr(p) \
({ \
_Static_assert((p) == NULL || sizeof(*(p)) == sizeof(long),\
#p " pointee should be a long-sized integer or a pointer"); \
(long *)(p); \
})
bool hashmap_find(const struct hashmap *map, long key, long *value);
#define hashmap__find(map, key, value) \
hashmap_find((map), (long)(key), hashmap_cast_ptr(value))
- hashmap__find macro casts key and value parameters to long
and long* respectively
- hashmap_cast_ptr ensures that value pointer points to a memory
of appropriate size.
This hack was suggested by Andrii Nakryiko in [1].
This is a follow up for [2].
[1] https://lore.kernel.org/bpf/CAEf4BzZ8KFneEJxFAaNCCFPGqp20hSpS2aCj76uRk3-qZUH5xg@mail.gmail.com/
[2] https://lore.kernel.org/bpf/af1facf9-7bc8-8a3d-0db4-7b3f333589a2@meta.com/T/#m65b28f1d6d969fcd318b556db6a3ad499a42607d
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221109142611.879983-2-eddyz87@gmail.com
A set of test cases to verify enum fwd resolution logic:
- verify that enum fwd can be resolved as full enum64;
- verify that enum64 fwd can be resolved as full enum;
- verify that enum size is considered when enums are compared for
equivalence.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221101235413.1824260-2-eddyz87@gmail.com
test_align selftest relies on BPF verifier log emitting register states
for specific instructions in expected format. Unfortunately, BPF
verifier precision backtracking log interferes with such expectations.
And instruction on which precision propagation happens sometimes don't
output full expected register states. This does indeed look like
something to be improved in BPF verifier, but is beyond the scope of
this patch set.
So to make test_align a bit more robust, inject few dummy R4 = R5
instructions which capture desired state of R5 and won't have precision
tracking logs on them. This fixes tests until we can improve BPF
verifier output in the presence of precision tracking.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20221104163649.121784-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
bpf-next 2022-11-02
We've added 70 non-merge commits during the last 14 day(s) which contain
a total of 96 files changed, 3203 insertions(+), 640 deletions(-).
The main changes are:
1) Make cgroup local storage available to non-cgroup attached BPF programs
such as tc BPF ones, from Yonghong Song.
2) Avoid unnecessary deadlock detection and failures wrt BPF task storage
helpers, from Martin KaFai Lau.
3) Add LLVM disassembler as default library for dumping JITed code
in bpftool, from Quentin Monnet.
4) Various kprobe_multi_link fixes related to kernel modules,
from Jiri Olsa.
5) Optimize x86-64 JIT with emitting BMI2-based shift instructions,
from Jie Meng.
6) Improve BPF verifier's memory type compatibility for map key/value
arguments, from Dave Marchevsky.
7) Only create mmap-able data section maps in libbpf when data is exposed
via skeletons, from Andrii Nakryiko.
8) Add an autoattach option for bpftool to load all object assets,
from Wang Yufen.
9) Various memory handling fixes for libbpf and BPF selftests,
from Xu Kuohai.
10) Initial support for BPF selftest's vmtest.sh on arm64,
from Manu Bretelle.
11) Improve libbpf's BTF handling to dedup identical structs,
from Alan Maguire.
12) Add BPF CI and denylist documentation for BPF selftests,
from Daniel Müller.
13) Check BPF cpumap max_entries before doing allocation work,
from Florian Lehner.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (70 commits)
samples/bpf: Fix typo in README
bpf: Remove the obsolte u64_stats_fetch_*_irq() users.
bpf: check max_entries before allocating memory
bpf: Fix a typo in comment for DFS algorithm
bpftool: Fix spelling mistake "disasembler" -> "disassembler"
selftests/bpf: Fix bpftool synctypes checking failure
selftests/bpf: Panic on hard/soft lockup
docs/bpf: Add documentation for new cgroup local storage
selftests/bpf: Add test cgrp_local_storage to DENYLIST.s390x
selftests/bpf: Add selftests for new cgroup local storage
selftests/bpf: Fix test test_libbpf_str/bpf_map_type_str
bpftool: Support new cgroup local storage
libbpf: Support new cgroup local storage
bpf: Implement cgroup storage available to non-cgroup-attached bpf progs
bpf: Refactor some inode/task/sk storage functions for reuse
bpf: Make struct cgroup btf id global
selftests/bpf: Tracing prog can still do lookup under busy lock
selftests/bpf: Ensure no task storage failure for bpf_lsm.s prog due to deadlock detection
bpf: Add new bpf_task_storage_delete proto with no deadlock detection
bpf: bpf_task_storage_delete_recur does lookup first before the deadlock check
...
====================
Link: https://lore.kernel.org/r/20221102062120.5724-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add four tests for new cgroup local storage, (1) testing bpf program helpers
and user space map APIs, (2) testing recursive fentry triggering won't deadlock,
(3) testing progs attached to cgroups, and (4) a negative test if the
bpf_cgrp_storage_get() helper key is not a cgroup btf id.
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221026042911.675546-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
