As reported by Byeonguk, the bad_words test in verifier_bits_iter.c
occasionally fails on s390 host. Quoting Ilya's explanation:
s390 kernel runs in a completely separate address space, there is no
user/kernel split at TASK_SIZE. The same address may be valid in both
the kernel and the user address spaces, there is no way to tell by
looking at it. The config option related to this property is
ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.
Also, unfortunately, 0 is a valid address in the s390 kernel address
space.
Fix the issue by using -4095 as the bad address for bits iterator, as
suggested by Ilya. Verify that bpf_iter_bits_new() returns -EINVAL for
NULL address and -EFAULT for bad address.
Fixes: ebafc1e535 ("selftests/bpf: Add three test cases for bits_iter")
Reported-by: Byeonguk Jeong <jungbu2855@gmail.com>
Closes: https://lore.kernel.org/bpf/ZycSXwjH4UTvx-Cn@ub22/
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20241105043057.3371482-1-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add more test cases for bits iterator:
(1) huge word test
Verify the multiplication overflow of nr_bits in bits_iter. Without
the overflow check, when nr_words is 67108865, nr_bits becomes 64,
causing bpf_probe_read_kernel_common() to corrupt the stack.
(2) max word test
Verify correct handling of maximum nr_words value (511).
(3) bad word test
Verify early termination of bits iteration when bits iterator
initialization fails.
Also rename bits_nomem to bits_too_big to better reflect its purpose.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20241030100516.3633640-6-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test added is a simplified reproducer from syzbot report [1].
If verifier does not insert checkpoint somewhere inside the loop,
verification of the program would take a very long time.
This would happen because mark_chain_precision() for register r7 would
constantly trace jump history of the loop back, processing many
iterations for each mark_chain_precision() call.
[1] https://lore.kernel.org/bpf/670429f6.050a0220.49194.0517.GAE@google.com/
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20241029172641.1042523-2-eddyz87@gmail.com
- Fix BPF verifier to not affect subreg_def marks in its range
propagation, from Eduard Zingerman.
- Fix a truncation bug in the BPF verifier's handling of
coerce_reg_to_size_sx, from Dimitar Kanaliev.
- Fix the BPF verifier's delta propagation between linked
registers under 32-bit addition, from Daniel Borkmann.
- Fix a NULL pointer dereference in BPF devmap due to missing
rxq information, from Florian Kauer.
- Fix a memory leak in bpf_core_apply, from Jiri Olsa.
- Fix an UBSAN-reported array-index-out-of-bounds in BTF
parsing for arrays of nested structs, from Hou Tao.
- Fix build ID fetching where memory areas backing the file
were created with memfd_secret, from Andrii Nakryiko.
- Fix BPF task iterator tid filtering which was incorrectly
using pid instead of tid, from Jordan Rome.
- Several fixes for BPF sockmap and BPF sockhash redirection
in combination with vsocks, from Michal Luczaj.
- Fix riscv BPF JIT and make BPF_CMPXCHG fully ordered,
from Andrea Parri.
- Fix riscv BPF JIT under CONFIG_CFI_CLANG to prevent the
possibility of an infinite BPF tailcall, from Pu Lehui.
- Fix a build warning from resolve_btfids that bpf_lsm_key_free
cannot be resolved, from Thomas Weißschuh.
- Fix a bug in kfunc BTF caching for modules where the wrong
BTF object was returned, from Toke Høiland-Jørgensen.
- Fix a BPF selftest compilation error in cgroup-related tests
with musl libc, from Tony Ambardar.
- Several fixes to BPF link info dumps to fill missing fields,
from Tyrone Wu.
- Add BPF selftests for kfuncs from multiple modules, checking
that the correct kfuncs are called, from Simon Sundberg.
- Ensure that internal and user-facing bpf_redirect flags
don't overlap, also from Toke Høiland-Jørgensen.
- Switch to use kvzmalloc to allocate BPF verifier environment,
from Rik van Riel.
- Use raw_spinlock_t in BPF ringbuf to fix a sleep in atomic
splat under RT, from Wander Lairson Costa.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:
- Fix BPF verifier to not affect subreg_def marks in its range
propagation (Eduard Zingerman)
- Fix a truncation bug in the BPF verifier's handling of
coerce_reg_to_size_sx (Dimitar Kanaliev)
- Fix the BPF verifier's delta propagation between linked registers
under 32-bit addition (Daniel Borkmann)
- Fix a NULL pointer dereference in BPF devmap due to missing rxq
information (Florian Kauer)
- Fix a memory leak in bpf_core_apply (Jiri Olsa)
- Fix an UBSAN-reported array-index-out-of-bounds in BTF parsing for
arrays of nested structs (Hou Tao)
- Fix build ID fetching where memory areas backing the file were
created with memfd_secret (Andrii Nakryiko)
- Fix BPF task iterator tid filtering which was incorrectly using pid
instead of tid (Jordan Rome)
- Several fixes for BPF sockmap and BPF sockhash redirection in
combination with vsocks (Michal Luczaj)
- Fix riscv BPF JIT and make BPF_CMPXCHG fully ordered (Andrea Parri)
- Fix riscv BPF JIT under CONFIG_CFI_CLANG to prevent the possibility
of an infinite BPF tailcall (Pu Lehui)
- Fix a build warning from resolve_btfids that bpf_lsm_key_free cannot
be resolved (Thomas Weißschuh)
- Fix a bug in kfunc BTF caching for modules where the wrong BTF object
was returned (Toke Høiland-Jørgensen)
- Fix a BPF selftest compilation error in cgroup-related tests with
musl libc (Tony Ambardar)
- Several fixes to BPF link info dumps to fill missing fields (Tyrone
Wu)
- Add BPF selftests for kfuncs from multiple modules, checking that the
correct kfuncs are called (Simon Sundberg)
- Ensure that internal and user-facing bpf_redirect flags don't overlap
(Toke Høiland-Jørgensen)
- Switch to use kvzmalloc to allocate BPF verifier environment (Rik van
Riel)
- Use raw_spinlock_t in BPF ringbuf to fix a sleep in atomic splat
under RT (Wander Lairson Costa)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (38 commits)
lib/buildid: Handle memfd_secret() files in build_id_parse()
selftests/bpf: Add test case for delta propagation
bpf: Fix print_reg_state's constant scalar dump
bpf: Fix incorrect delta propagation between linked registers
bpf: Properly test iter/task tid filtering
bpf: Fix iter/task tid filtering
riscv, bpf: Make BPF_CMPXCHG fully ordered
bpf, vsock: Drop static vsock_bpf_prot initialization
vsock: Update msg_count on read_skb()
vsock: Update rx_bytes on read_skb()
bpf, sockmap: SK_DROP on attempted redirects of unsupported af_vsock
selftests/bpf: Add asserts for netfilter link info
bpf: Fix link info netfilter flags to populate defrag flag
selftests/bpf: Add test for sign extension in coerce_subreg_to_size_sx()
selftests/bpf: Add test for truncation after sign extension in coerce_reg_to_size_sx()
bpf: Fix truncation bug in coerce_reg_to_size_sx()
selftests/bpf: Assert link info uprobe_multi count & path_size if unset
bpf: Fix unpopulated path_size when uprobe_multi fields unset
selftests/bpf: Fix cross-compiling urandom_read
selftests/bpf: Add test for kfunc module order
...
Add a test for unsigned ranges after signed extension instruction. This
case isn't currently covered by existing tests in verifier_movsx.c.
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Dimitar Kanaliev <dimitar.kanaliev@siteground.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20241014121155.92887-4-dimitar.kanaliev@siteground.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add test that checks whether unsigned ranges deduced by the verifier for
sign extension instruction is correct. Without previous patch that
fixes truncation in coerce_reg_to_size_sx() this test fails.
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Dimitar Kanaliev <dimitar.kanaliev@siteground.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20241014121155.92887-3-dimitar.kanaliev@siteground.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a test case for kfuncs from multiple external modules, checking
that the correct kfuncs are called regardless of which order they're
called in. Specifically, check that calling the kfuncs in an order
different from the one the modules' BTF are loaded in works.
Signed-off-by: Simon Sundberg <simon.sundberg@kau.se>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20241010-fix-kfunc-btf-caching-for-modules-v2-3-745af6c1af98@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add three success test cases to test the flattening of array of nested
struct. For these three tests, the number of special fields in map is
BTF_FIELDS_MAX, but the array is defined in structs with different
nested level.
Add one failure test case for the flattening as well. In the test case,
the number of special fields in map is BTF_FIELDS_MAX + 1. It will make
btf_parse_fields() in map_create() return -E2BIG, the creation of map
will succeed, but the load of program will fail because the btf_record
is invalid for the map.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20241008071114.3718177-3-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
The current xdp_devmap_attach test attaches a program
that redirects to another program via devmap.
It is, however, never executed, so do that to catch
any bugs that might occur during execution.
Also, execute the same for a veth pair so that we
also cover the non-generic path.
Warning: Running this without the bugfix in this series
will likely crash your system.
Signed-off-by: Florian Kauer <florian.kauer@linutronix.de>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20240911-devel-koalo-fix-ingress-ifindex-v4-2-5c643ae10258@linutronix.de
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
This test was added because of a bug in verifier.c:sync_linked_regs(),
upon range propagation it destroyed subreg_def marks for registers.
The test is written in a way to return an upper half of a register
that is affected by range propagation and must have it's subreg_def
preserved. This gives a return value of 0 and leads to undefined
return value if subreg_def mark is not preserved.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240924210844.1758441-2-eddyz87@gmail.com
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Merge tag 'bpf-next-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Introduce '__attribute__((bpf_fastcall))' for helpers and kfuncs with
corresponding support in LLVM.
It is similar to existing 'no_caller_saved_registers' attribute in
GCC/LLVM with a provision for backward compatibility. It allows
compilers generate more efficient BPF code assuming the verifier or
JITs will inline or partially inline a helper/kfunc with such
attribute. bpf_cast_to_kern_ctx, bpf_rdonly_cast,
bpf_get_smp_processor_id are the first set of such helpers.
- Harden and extend ELF build ID parsing logic.
When called from sleepable context the relevants parts of ELF file
will be read to find and fetch .note.gnu.build-id information. Also
harden the logic to avoid TOCTOU, overflow, out-of-bounds problems.
- Improvements and fixes for sched-ext:
- Allow passing BPF iterators as kfunc arguments
- Make the pointer returned from iter_next method trusted
- Fix x86 JIT convergence issue due to growing/shrinking conditional
jumps in variable length encoding
- BPF_LSM related:
- Introduce few VFS kfuncs and consolidate them in
fs/bpf_fs_kfuncs.c
- Enforce correct range of return values from certain LSM hooks
- Disallow attaching to other LSM hooks
- Prerequisite work for upcoming Qdisc in BPF:
- Allow kptrs in program provided structs
- Support for gen_epilogue in verifier_ops
- Important fixes:
- Fix uprobe multi pid filter check
- Fix bpf_strtol and bpf_strtoul helpers
- Track equal scalars history on per-instruction level
- Fix tailcall hierarchy on x86 and arm64
- Fix signed division overflow to prevent INT_MIN/-1 trap on x86
- Fix get kernel stack in BPF progs attached to tracepoint:syscall
- Selftests:
- Add uprobe bench/stress tool
- Generate file dependencies to drastically improve re-build time
- Match JIT-ed and BPF asm with __xlated/__jited keywords
- Convert older tests to test_progs framework
- Add support for RISC-V
- Few fixes when BPF programs are compiled with GCC-BPF backend
(support for GCC-BPF in BPF CI is ongoing in parallel)
- Add traffic monitor
- Enable cross compile and musl libc
* tag 'bpf-next-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (260 commits)
btf: require pahole 1.21+ for DEBUG_INFO_BTF with default DWARF version
btf: move pahole check in scripts/link-vmlinux.sh to lib/Kconfig.debug
btf: remove redundant CONFIG_BPF test in scripts/link-vmlinux.sh
bpf: Call the missed kfree() when there is no special field in btf
bpf: Call the missed btf_record_free() when map creation fails
selftests/bpf: Add a test case to write mtu result into .rodata
selftests/bpf: Add a test case to write strtol result into .rodata
selftests/bpf: Rename ARG_PTR_TO_LONG test description
selftests/bpf: Fix ARG_PTR_TO_LONG {half-,}uninitialized test
bpf: Zero former ARG_PTR_TO_{LONG,INT} args in case of error
bpf: Improve check_raw_mode_ok test for MEM_UNINIT-tagged types
bpf: Fix helper writes to read-only maps
bpf: Remove truncation test in bpf_strtol and bpf_strtoul helpers
bpf: Fix bpf_strtol and bpf_strtoul helpers for 32bit
selftests/bpf: Add tests for sdiv/smod overflow cases
bpf: Fix a sdiv overflow issue
libbpf: Add bpf_object__token_fd accessor
docs/bpf: Add missing BPF program types to docs
docs/bpf: Add constant values for linkages
bpf: Use fake pt_regs when doing bpf syscall tracepoint tracing
...
Add a test which attempts to call bpf_check_mtu() and writes the MTU
into .rodata section of the BPF program, and for comparison this adds
test cases also for .bss and .data section again. The bpf_check_mtu()
is a bit more special in that the passed mtu argument is read and
written by the helper (instead of just written to). Assert that writes
into .rodata remain rejected by the verifier.
# ./vmtest.sh -- ./test_progs -t verifier_const
[...]
./test_progs -t verifier_const
[ 1.657367] bpf_testmod: loading out-of-tree module taints kernel.
[ 1.657773] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
#473/1 verifier_const/rodata/strtol: write rejected:OK
#473/2 verifier_const/bss/strtol: write accepted:OK
#473/3 verifier_const/data/strtol: write accepted:OK
#473/4 verifier_const/rodata/mtu: write rejected:OK
#473/5 verifier_const/bss/mtu: write accepted:OK
#473/6 verifier_const/data/mtu: write accepted:OK
#473 verifier_const:OK
[...]
Summary: 2/10 PASSED, 0 SKIPPED, 0 FAILED
For comparison, without the MEM_UNINIT on bpf_check_mtu's proto:
# ./vmtest.sh -- ./test_progs -t verifier_const
[...]
#473/3 verifier_const/data/strtol: write accepted:OK
run_subtest:PASS:obj_open_mem 0 nsec
run_subtest:FAIL:unexpected_load_success unexpected success: 0
#473/4 verifier_const/rodata/mtu: write rejected:FAIL
#473/5 verifier_const/bss/mtu: write accepted:OK
#473/6 verifier_const/data/mtu: write accepted:OK
#473 verifier_const:FAIL
[...]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20240913191754.13290-9-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The assumption of 'in privileged mode reads from uninitialized stack locations
are permitted' is not quite correct since the verifier was probing for read
access rather than write access. Both tests need to be annotated as __success
for privileged and unprivileged.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240913191754.13290-6-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Subtests are added to exercise the patched code which handles
- LLONG_MIN/-1
- INT_MIN/-1
- LLONG_MIN%-1
- INT_MIN%-1
where -1 could be an immediate or in a register.
Without the previous patch, all these cases will crash the kernel on
x86_64 platform.
Additional tests are added to use small values (e.g. -5/-1, 5%-1, etc.)
in order to exercise the additional logic with patched insns.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240913150332.1188102-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
llvm change [1] made a change such that __sync_fetch_and_{and,or,xor}()
will generate atomic_fetch_*() insns even if the return value is not used.
This is a deliberate choice to make sure barrier semantics are preserved
from source code to asm insn.
But the change in [1] caused arena_atomics selftest failure.
test_arena_atomics:PASS:arena atomics skeleton open 0 nsec
libbpf: prog 'and': BPF program load failed: Permission denied
libbpf: prog 'and': -- BEGIN PROG LOAD LOG --
arg#0 reference type('UNKNOWN ') size cannot be determined: -22
0: R1=ctx() R10=fp0
; if (pid != (bpf_get_current_pid_tgid() >> 32)) @ arena_atomics.c:87
0: (18) r1 = 0xffffc90000064000 ; R1_w=map_value(map=arena_at.bss,ks=4,vs=4)
2: (61) r6 = *(u32 *)(r1 +0) ; R1_w=map_value(map=arena_at.bss,ks=4,vs=4) R6_w=scalar(smin=0,smax=umax=0xffffffff,v
ar_off=(0x0; 0xffffffff))
3: (85) call bpf_get_current_pid_tgid#14 ; R0_w=scalar()
4: (77) r0 >>= 32 ; R0_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff))
5: (5d) if r0 != r6 goto pc+11 ; R0_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R6_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0x)
; __sync_fetch_and_and(&and64_value, 0x011ull << 32); @ arena_atomics.c:91
6: (18) r1 = 0x100000000060 ; R1_w=scalar()
8: (bf) r1 = addr_space_cast(r1, 0, 1) ; R1_w=arena
9: (18) r2 = 0x1100000000 ; R2_w=0x1100000000
11: (db) r2 = atomic64_fetch_and((u64 *)(r1 +0), r2)
BPF_ATOMIC stores into R1 arena is not allowed
processed 9 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
-- END PROG LOAD LOG --
libbpf: prog 'and': failed to load: -13
libbpf: failed to load object 'arena_atomics'
libbpf: failed to load BPF skeleton 'arena_atomics': -13
test_arena_atomics:FAIL:arena atomics skeleton load unexpected error: -13 (errno 13)
#3 arena_atomics:FAIL
The reason of the failure is due to [2] where atomic{64,}_fetch_{and,or,xor}() are not
allowed by arena addresses.
Version 2 of the patch fixed the issue by using inline asm ([3]). But further discussion
suggested to find a way from source to generate locked insn which is more user
friendly. So in not-merged llvm patch ([4]), if relax memory ordering is used and
the return value is not used, locked insn could be generated.
So with llvm patch [4] to compile the bpf selftest, the following code
__c11_atomic_fetch_and(&and64_value, 0x011ull << 32, memory_order_relaxed);
is able to generate locked insn, hence fixing the selftest failure.
[1] https://github.com/llvm/llvm-project/pull/106494
[2] d503a04f8b ("bpf: Add support for certain atomics in bpf_arena to x86 JIT")
[3] https://lore.kernel.org/bpf/20240803025928.4184433-1-yonghong.song@linux.dev/
[4] https://github.com/llvm/llvm-project/pull/107343
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240909223431.1666305-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a new set of tests validating behavior of capturing stack traces
with build ID. We extend uprobe_multi target binary with ability to
trigger uprobe (so that we can capture stack traces from it), but also
we allow to force build ID data to be either resident or non-resident in
memory (see also a comment about quirks of MADV_PAGEOUT).
That way we can validate that in non-sleepable context we won't get
build ID (as expected), but with sleepable uprobes we will get that
build ID regardless of it being physically present in memory.
Also, we add a small add-on linker script which reorders
.note.gnu.build-id section and puts it after (big) .text section,
putting build ID data outside of the very first page of ELF file. This
will test all the relaxations we did in build ID parsing logic in kernel
thanks to freader abstraction.
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240829174232.3133883-11-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add 3 test cases for skb dynptr used in tp_btf:
- test_dynptr_skb_tp_btf: use skb dynptr in tp_btf and make sure it is
read-only.
- skb_invalid_ctx_fentry/skb_invalid_ctx_fexit: bpf_dynptr_from_skb
should fail in fentry/fexit.
In test_dynptr_skb_tp_btf, to trigger the tracepoint in kfree_skb,
test_pkt_access is used for its test_run, as in kfree_skb.c. Because the
test process is different from others, a new setup type is defined,
i.e., SETUP_SKB_PROG_TP.
The result is like:
$ ./test_progs -t 'dynptr/test_dynptr_skb_tp_btf'
#84/14 dynptr/test_dynptr_skb_tp_btf:OK
#84 dynptr:OK
#127 kfunc_dynptr_param:OK
Summary: 2/1 PASSED, 0 SKIPPED, 0 FAILED
$ ./test_progs -t 'dynptr/skb_invalid_ctx_f'
#84/85 dynptr/skb_invalid_ctx_fentry:OK
#84/86 dynptr/skb_invalid_ctx_fexit:OK
#84 dynptr:OK
#127 kfunc_dynptr_param:OK
Summary: 2/2 PASSED, 0 SKIPPED, 0 FAILED
Also fix two coding style nits (change spaces to tabs).
Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240911033719.91468-6-lulie@linux.alibaba.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
When "arg#%d expected pointer to ctx, but got %s" error is printed, both
template parts actually point to the type of the argument, therefore, it
will also say "but got PTR", regardless of what was the actual register
type.
Fix the message to print the register type in the second part of the
template, change the existing test to adapt to the new format, and add a
new test to test the case when arg is a pointer to context, but reg is a
scalar.
Fixes: 00b85860fe ("bpf: Rewrite kfunc argument handling")
Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/20240909133909.1315460-1-maxim@isovalent.com
Recently, when compiling bpf selftests on RV64, the following
compilation failure occurred:
progs/bpf_dctcp.c:29:21: error: redefinition of 'fallback' as different kind of symbol
29 | volatile const char fallback[TCP_CA_NAME_MAX];
| ^
/workspace/tools/testing/selftests/bpf/tools/include/vmlinux.h:86812:15: note: previous definition is here
86812 | typedef u32 (*fallback)(u32, const unsigned char *, size_t);
The reason is that the `fallback` symbol has been defined in
arch/riscv/lib/crc32.c, which will cause symbol conflicts when vmlinux.h
is included in bpf_dctcp. Let we rename `fallback` string to
`fallback_cc` in bpf_dctcp to fix this compilation failure.
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20240905081401.1894789-3-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The idea is to create and monitor 3 uprobes, each trigered in separate
process and make sure the bpf program gets executed just for the proper
PID specified via pid filter.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240905115124.1503998-4-jolsa@kernel.org
Considering that CO-RE direct read access to the first system call
argument is already available on s390 and arm64, let's enable
test_bpf_syscall_macro:syscall_arg1 on these architectures.
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240831041934.1629216-4-pulehui@huaweicloud.com
The core part of the selftest, i.e., the je <-> jmp cycle, mimics the
original sched-ext bpf program. The test will fail without the
previous patch.
I tried to create some cases for other potential cycles
(je <-> je, jmp <-> je and jmp <-> jmp) with similar pattern
to the test in this patch, but failed. So this patch
only contains one test for je <-> jmp cycle.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240904221256.37389-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds test cases for iter next method returning valid
pointer, which can also used as usage examples.
Currently iter next method should return valid pointer.
iter_next_trusted is the correct usage and test if iter next method
return valid pointer. bpf_iter_task_vma_next has KF_RET_NULL flag,
so the returned pointer may be NULL. We need to check if the pointer
is NULL before using it.
iter_next_trusted_or_null is the incorrect usage. There is no checking
before using the pointer, so it will be rejected by the verifier.
iter_next_rcu and iter_next_rcu_or_null are similar test cases for
KF_RCU_PROTECTED iterators.
iter_next_rcu_not_trusted is used to test that the pointer returned by
iter next method of KF_RCU_PROTECTED iterator cannot be passed in
KF_TRUSTED_ARGS kfuncs.
iter_next_ptr_mem_not_trusted is used to test that base type
PTR_TO_MEM should not be combined with type flag PTR_TRUSTED.
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Link: https://lore.kernel.org/r/AM6PR03MB5848709758F6922F02AF9F1F99962@AM6PR03MB5848.eurprd03.prod.outlook.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch tests the epilogue patching when the main prog has
multiple BPF_EXIT. The verifier should have patched the 2nd (and
later) BPF_EXIT with a BPF_JA that goes back to the earlier
patched epilogue instructions.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-10-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds a pro/epilogue test when the main prog has a goto insn
that goes back to the very first instruction of the prog. It is
to test the correctness of the adjust_jmp_off(prog, 0, delta)
after the verifier has applied the prologue and/or epilogue patch.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-9-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds a gen_epilogue test to test a main prog
using a bpf_tail_call.
A non test_loader test is used. The tailcall target program,
"test_epilogue_subprog", needs to be used in a struct_ops map
before it can be loaded. Another struct_ops map is also needed
to host the actual "test_epilogue_tailcall" struct_ops program
that does the bpf_tail_call. The earlier test_loader patch
will attach all struct_ops maps but the bpf_testmod.c does
not support >1 attached struct_ops.
The earlier patch used the test_loader which has already covered
checking for the patched pro/epilogue instructions. This is done
by the __xlated tag.
This patch goes for the regular skel load and syscall test to do
the tailcall test that can also allow to directly pass the
the "struct st_ops_args *args" as ctx_in to the
SEC("syscall") program.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-8-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This test adds a new struct_ops "bpf_testmod_st_ops" in bpf_testmod.
The ops of the bpf_testmod_st_ops is triggered by new kfunc calls
"bpf_kfunc_st_ops_test_*logue". These new kfunc calls are
primarily used by the SEC("syscall") program. The test triggering
sequence is like:
SEC("syscall")
syscall_prologue(struct st_ops_args *args)
bpf_kfunc_st_op_test_prologue(args)
st_ops->test_prologue(args)
.gen_prologue adds 1000 to args->a
.gen_epilogue adds 10000 to args->a
.gen_epilogue will also set the r0 to 2 * args->a.
The .gen_prologue and .gen_epilogue of the bpf_testmod_st_ops
will test the prog->aux->attach_func_name to decide if
it needs to generate codes.
The main programs of the pro_epilogue.c will call a
new kfunc bpf_kfunc_st_ops_inc10 which does "args->a += 10".
It will also call a subprog() which does "args->a += 1".
This patch uses the test_loader infra to check the __xlated
instructions patched after gen_prologue and/or gen_epilogue.
The __xlated check is based on Eduard's example (Thanks!) in v1.
args->a is returned by the struct_ops prog (either the main prog
or the epilogue). Thus, the __retval of the SEC("syscall") prog
is checked. For example, when triggering the ops in the
'SEC("struct_ops/test_epilogue") int test_epilogue'
The expected args->a is +1 (subprog call) + 10 (kfunc call)
+ 10000 (.gen_epilogue) = 10011.
The expected return value is 2 * 10011 (.gen_epilogue).
Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240829210833.388152-7-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When dropping a local kptr, any kptr stashed into it is supposed to be
freed through bpf_obj_free_fields->__bpf_obj_drop_impl recursively. Add a
test to make sure it happens.
The test first stashes a referenced kptr to "struct task" into a local
kptr and gets the reference count of the task. Then, it drops the local
kptr and reads the reference count of the task again. Since
bpf_obj_free_fields and __bpf_obj_drop_impl will go through the local kptr
recursively during bpf_obj_drop, the dtor of the stashed task kptr should
eventually be called. The second reference count should be one less than
the first one.
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240827011301.608620-1-amery.hung@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds test cases for zero offset (implicit cast) or non-zero
offset pointer as KF_ACQUIRE kfuncs argument. Currently KF_ACQUIRE
kfuncs should support passing in pointers like &sk->sk_write_queue
(non-zero offset) or &sk->__sk_common (zero offset) and not be rejected
by the verifier.
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Link: https://lore.kernel.org/r/AM6PR03MB5848CB6F0D4D9068669A905B99952@AM6PR03MB5848.eurprd03.prod.outlook.com
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:
====================
pull-request: bpf-next 2024-08-23
We've added 10 non-merge commits during the last 15 day(s) which contain
a total of 10 files changed, 222 insertions(+), 190 deletions(-).
The main changes are:
1) Add TCP_BPF_SOCK_OPS_CB_FLAGS to bpf_*sockopt() to address the case
when long-lived sockets miss a chance to set additional callbacks
if a sockops program was not attached early in their lifetime,
from Alan Maguire.
2) Add a batch of BPF selftest improvements which fix a few bugs and add
missing features to improve the test coverage of sockmap/sockhash,
from Michal Luczaj.
3) Fix a false-positive Smatch-reported off-by-one in tcp_validate_cookie()
which is part of the test_tcp_custom_syncookie BPF selftest,
from Kuniyuki Iwashima.
4) Fix the flow_dissector BPF selftest which had a bug in IP header's
tot_len calculation doing subtraction after htons() instead of inside
htons(), from Asbjørn Sloth Tønnesen.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
selftest: bpf: Remove mssind boundary check in test_tcp_custom_syncookie.c.
selftests/bpf: Introduce __attribute__((cleanup)) in create_pair()
selftests/bpf: Exercise SOCK_STREAM unix_inet_redir_to_connected()
selftests/bpf: Honour the sotype of af_unix redir tests
selftests/bpf: Simplify inet_socketpair() and vsock_socketpair_connectible()
selftests/bpf: Socket pair creation, cleanups
selftests/bpf: Support more socket types in create_pair()
selftests/bpf: Avoid subtraction after htons() in ipip tests
selftests/bpf: add sockopt tests for TCP_BPF_SOCK_OPS_CB_FLAGS
bpf/bpf_get,set_sockopt: add option to set TCP-BPF sock ops flags
====================
Link: https://patch.msgid.link/20240823134959.1091-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Test stashing both referenced kptr and local kptr into local kptrs. Then,
test unstashing them.
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Link: https://lore.kernel.org/r/20240813212424.2871455-6-amery.hung@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Depending on kernel parameters, x86 jit generates either retq or jump
to rethunk for 'exit' instruction. The difference could be seen when
kernel is booted with and without mitigations=off parameter.
Relax the verifier_tailcall_jit test case to match both variants.
Fixes: e5bdd6a8be ("selftests/bpf: validate jit behaviour for tail calls")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240823080644.263943-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a selftest to confirm the issue, which gets -EINVAL when update
attached freplace prog to prog_array map, has been fixed.
cd tools/testing/selftests/bpf; ./test_progs -t tailcalls
328/25 tailcalls/tailcall_freplace:OK
328 tailcalls:OK
Summary: 1/25 PASSED, 0 SKIPPED, 0 FAILED
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Link: https://lore.kernel.org/r/20240728114612.48486-3-leon.hwang@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Use kfunc_bpf_cast_to_kern_ctx() and kfunc_bpf_rdonly_cast() to verify
that bpf_fastcall pattern is recognized for kfunc calls.
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240822084112.3257995-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Attribute used by LLVM implementation of the feature had been changed
from no_caller_saved_registers to bpf_fastcall (see [1]).
This commit replaces references to nocsr by references to bpf_fastcall
to keep LLVM and selftests parts in sync.
[1] https://github.com/llvm/llvm-project/pull/105417
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240822084112.3257995-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Smatch reported a possible off-by-one in tcp_validate_cookie().
However, it's false positive because the possible range of mssind is
limited from 0 to 3 by the preceding calculation.
mssind = (cookie & (3 << 6)) >> 6;
Now, the verifier does not complain without the boundary check.
Let's remove the checks.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/bpf/6ae12487-d3f1-488b-9514-af0dac96608f@stanley.mountain/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240821013425.49316-1-kuniyu@amazon.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
