WWang Huaibpf: Remove mark_precise_scalar_ids()
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.gitignore: add SPDX License Identifier Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 6 年前 | |
bpf, x86: Fix BPF_FETCH atomic and/or/xor with r0 as src This code generates a CMPXCHG loop in order to implement atomic_fetch bitwise operations. Because CMPXCHG is hard-coded to use rax (which holds the BPF r0 value), it saves the _real_ r0 value into the internal "ax" temporary register and restores it once the loop is complete. In the middle of the loop, the actual bitwise operation is performed using src_reg. The bug occurs when src_reg is r0: as described above, r0 has been clobbered and the real r0 value is in the ax register. Therefore, perform this operation on the ax register instead, when src_reg is r0. Fixes: 981f94c3e921 ("bpf: Add bitwise atomic instructions") Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: KP Singh <kpsingh@kernel.org> Link: https://lore.kernel.org/bpf/20210216125307.1406237-1-jackmanb@google.com | 5 年前 | |
bpf: Propagate stack bounds to registers in atomics w/ BPF_FETCH When BPF_FETCH is set, atomic instructions load a value from memory into a register. The current verifier code first checks via check_mem_access whether we can access the memory, and then checks via check_reg_arg whether we can write into the register. For loads, check_reg_arg has the side-effect of marking the register's value as unkonwn, and check_mem_access has the side effect of propagating bounds from memory to the register. This currently only takes effect for stack memory. Therefore with the current order, bounds information is thrown away, but by simply reversing the order of check_reg_arg vs. check_mem_access, we can instead propagate bounds smartly. A simple test is added with an infinite loop that can only be proved unreachable if this propagation is present. This is implemented both with C and directly in test_verifier using assembly. Suggested-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210202135002.4024825-1-jackmanb@google.com | 5 年前 | |
bpf: Fix accesses to uninit stack slots [ Upstream commit 6b4a64bafd107e521c01eec3453ce94a3fb38529 ] Privileged programs are supposed to be able to read uninitialized stack memory (ever since 6715df8d5) but, before this patch, these accesses were permitted inconsistently. In particular, accesses were permitted above state->allocated_stack, but not below it. In other words, if the stack was already "large enough", the access was permitted, but otherwise the access was rejected instead of being allowed to "grow the stack". This undesired rejection was happening in two places: - in check_stack_slot_within_bounds() - in check_stack_range_initialized() This patch arranges for these accesses to be permitted. A bunch of tests that were relying on the old rejection had to change; all of them were changed to add also run unprivileged, in which case the old behavior persists. One tests couldn't be updated - global_func16 - because it can't run unprivileged for other reasons. This patch also fixes the tracking of the stack size for variable-offset reads. This second fix is bundled in the same commit as the first one because they're inter-related. Before this patch, writes to the stack using registers containing a variable offset (as opposed to registers with fixed, known values) were not properly contributing to the function's needed stack size. As a result, it was possible for a program to verify, but then to attempt to read out-of-bounds data at runtime because a too small stack had been allocated for it. Each function tracks the size of the stack it needs in bpf_subprog_info.stack_depth, which is maintained by update_stack_depth(). For regular memory accesses, check_mem_access() was calling update_state_depth() but it was passing in only the fixed part of the offset register, ignoring the variable offset. This was incorrect; the minimum possible value of that register should be used instead. This tracking is now fixed by centralizing the tracking of stack size in grow_stack_state(), and by lifting the calls to grow_stack_state() to check_stack_access_within_bounds() as suggested by Andrii. The code is now simpler and more convincingly tracks the correct maximum stack size. check_stack_range_initialized() can now rely on enough stack having been allocated for the access; this helps with the fix for the first issue. A few tests were changed to also check the stack depth computation. The one that fails without this patch is verifier_var_off:stack_write_priv_vs_unpriv. Fixes: 01f810ace9ed3 ("bpf: Allow variable-offset stack access") Reported-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231208032519.260451-3-andreimatei1@gmail.com Closes: https://lore.kernel.org/bpf/CABWLsev9g8UP_c3a=1qbuZUi20tGoUXoU07FPf-5FLvhOKOY+Q@mail.gmail.com/ Signed-off-by: Sasha Levin <sashal@kernel.org> | 2 年前 | |
bpf, selftests: Add test case for atomic fetch on spilled pointer Test whether unprivileged would be able to leak the spilled pointer either by exporting the returned value from the atomic{32,64} operation or by reading and exporting the value from the stack after the atomic operation took place. Note that for unprivileged, the below atomic cmpxchg test case named "Dest pointer in r0 - succeed" is failing. The reason is that in the dst memory location (r10 -8) there is the spilled register r10: 0: R1=ctx(id=0,off=0,imm=0) R10=fp0 0: (bf) r0 = r10 1: R0_w=fp0 R1=ctx(id=0,off=0,imm=0) R10=fp0 1: (7b) *(u64 *)(r10 -8) = r0 2: R0_w=fp0 R1=ctx(id=0,off=0,imm=0) R10=fp0 fp-8_w=fp 2: (b7) r1 = 0 3: R0_w=fp0 R1_w=invP0 R10=fp0 fp-8_w=fp 3: (db) r0 = atomic64_cmpxchg((u64 *)(r10 -8), r0, r1) 4: R0_w=fp0 R1_w=invP0 R10=fp0 fp-8_w=mmmmmmmm 4: (79) r1 = *(u64 *)(r0 -8) 5: R0_w=fp0 R1_w=invP(id=0) R10=fp0 fp-8_w=mmmmmmmm 5: (b7) r0 = 0 6: R0_w=invP0 R1_w=invP(id=0) R10=fp0 fp-8_w=mmmmmmmm 6: (95) exit However, allowing this case for unprivileged is a bit useless given an update with a new pointer will fail anyway: 0: R1=ctx(id=0,off=0,imm=0) R10=fp0 0: (bf) r0 = r10 1: R0_w=fp0 R1=ctx(id=0,off=0,imm=0) R10=fp0 1: (7b) *(u64 *)(r10 -8) = r0 2: R0_w=fp0 R1=ctx(id=0,off=0,imm=0) R10=fp0 fp-8_w=fp 2: (db) r0 = atomic64_cmpxchg((u64 *)(r10 -8), r0, r10) R10 leaks addr into mem Acked-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 4 年前 | |
bpf: Add tests for new BPF atomic operations The prog_test that's added depends on Clang/LLVM features added by Yonghong in commit 286daafd6512 (was https://reviews.llvm.org/D72184). Note the use of a define called ENABLE_ATOMICS_TESTS: this is used to: - Avoid breaking the build for people on old versions of Clang - Avoid needing separate lists of test objects for no_alu32, where atomics are not supported even if Clang has the feature. The atomics_test.o BPF object is built unconditionally both for test_progs and test_progs-no_alu32. For test_progs, if Clang supports atomics, ENABLE_ATOMICS_TESTS is defined, so it includes the proper test code. Otherwise, progs and global vars are defined anyway, as stubs; this means that the skeleton user code still builds. The atomics_test.o userspace object is built once and used for both test_progs and test_progs-no_alu32. A variable called skip_tests is defined in the BPF object's data section, which tells the userspace object whether to skip the atomics test. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-11-jackmanb@google.com | 5 年前 | |
bpf: Small BPF verifier log improvements In particular these include: 1) Remove output of inv for scalars in print_verifier_state 2) Replace inv with scalar in verifier error messages 3) Remove _value suffixes for umin/umax/s32_min/etc (except map_value) 4) Remove output of id=0 5) Remove output of ref_obj_id=0 Signed-off-by: Mykola Lysenko <mykolal@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220301222745.1667206-1-mykolal@fb.com | 4 年前 | |
bpf: Explicitly zero-extend R0 after 32-bit cmpxchg As pointed out by Ilya and explained in the new comment, there's a discrepancy between x86 and BPF CMPXCHG semantics: BPF always loads the value from memory into r0, while x86 only does so when r0 and the value in memory are different. The same issue affects s390. At first this might sound like pure semantics, but it makes a real difference when the comparison is 32-bit, since the load will zero-extend r0/rax. The fix is to explicitly zero-extend rax after doing such a CMPXCHG. Since this problem affects multiple archs, this is done in the verifier by patching in a BPF_ZEXT_REG instruction after every 32-bit cmpxchg. Any archs that don't need such manual zero-extension can do a look-ahead with insn_is_zext to skip the unnecessary mov. Note this still goes on top of Ilya's patch: https://lore.kernel.org/bpf/20210301154019.129110-1-iii@linux.ibm.com/T/#u Differences v5->v6[1]: - Moved is_cmpxchg_insn and ensured it can be safely re-used. Also renamed it and removed 'inline' to match the style of the is_*_function helpers. - Fixed up comments in verifier test (thanks for the careful review, Martin!) Differences v4->v5[1]: - Moved the logic entirely into opt_subreg_zext_lo32_rnd_hi32, thanks to Martin for suggesting this. Differences v3->v4[1]: - Moved the optimization against pointless zext into the correct place: opt_subreg_zext_lo32_rnd_hi32 is called _after_ fixup_bpf_calls. Differences v2->v3[1]: - Moved patching into fixup_bpf_calls (patch incoming to rename this function) - Added extra commentary on bpf_jit_needs_zext - Added check to avoid adding a pointless zext(r0) if there's already one there. Difference v1->v2[1]: Now solved centrally in the verifier instead of specifically for the x86 JIT. Thanks to Ilya and Daniel for the suggestions! [1] v5: https://lore.kernel.org/bpf/CA+i-1C3ytZz6FjcPmUg5s4L51pMQDxWcZNvM86w4RHZ_o2khwg@mail.gmail.com/T/#t v4: https://lore.kernel.org/bpf/CA+i-1C3ytZz6FjcPmUg5s4L51pMQDxWcZNvM86w4RHZ_o2khwg@mail.gmail.com/T/#t v3: https://lore.kernel.org/bpf/08669818-c99d-0d30-e1db-53160c063611@iogearbox.net/T/#t v2: https://lore.kernel.org/bpf/08669818-c99d-0d30-e1db-53160c063611@iogearbox.net/T/#t v1: https://lore.kernel.org/bpf/d7ebaefb-bfd6-a441-3ff2-2fdfe699b1d2@iogearbox.net/T/#t Reported-by: Ilya Leoshkevich <iii@linux.ibm.com> Fixes: 5ffa25502b5a ("bpf: Add instructions for atomic_[cmp]xchg") Signed-off-by: Brendan Jackman <jackmanb@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 5 年前 | |
bpf: Add tests for new BPF atomic operations The prog_test that's added depends on Clang/LLVM features added by Yonghong in commit 286daafd6512 (was https://reviews.llvm.org/D72184). Note the use of a define called ENABLE_ATOMICS_TESTS: this is used to: - Avoid breaking the build for people on old versions of Clang - Avoid needing separate lists of test objects for no_alu32, where atomics are not supported even if Clang has the feature. The atomics_test.o BPF object is built unconditionally both for test_progs and test_progs-no_alu32. For test_progs, if Clang supports atomics, ENABLE_ATOMICS_TESTS is defined, so it includes the proper test code. Otherwise, progs and global vars are defined anyway, as stubs; this means that the skeleton user code still builds. The atomics_test.o userspace object is built once and used for both test_progs and test_progs-no_alu32. A variable called skip_tests is defined in the BPF object's data section, which tells the userspace object whether to skip the atomics test. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-11-jackmanb@google.com | 5 年前 | |
selftests/bpf: Fix endianness issues in atomic tests Atomic tests store a DW, but then load it back as a W from the same address. This doesn't work on big-endian systems, and since the point of those tests is not testing narrow loads, fix simply by loading a DW. Fixes: 98d666d05a1d ("bpf: Add tests for new BPF atomic operations") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210210020713.77911-1-iii@linux.ibm.com | 5 年前 | |
selftests/bpf: Fix test_verifier after introducing resolve_pseudo_ldimm64 Commit 4976b718c355 ("bpf: Introduce pseudo_btf_id") switched the order of check_subprogs() and resolve_pseudo_ldimm() in the verifier. Now an empty prog expects to see the error "last insn is not an the prog of a single invalid ldimm exit or jmp" instead, because the check for subprogs comes first. It's now pointless to validate that half of ldimm64 won't be the last instruction. Tested: # ./test_verifier Summary: 1129 PASSED, 537 SKIPPED, 0 FAILED and the full set of bpf selftests. Fixes: 4976b718c355 ("bpf: Introduce pseudo_btf_id") Signed-off-by: Hao Luo <haoluo@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201007022857.2791884-1-haoluo@google.com | 5 年前 | |
selftests: bpf: break up test_verifier Break up the first 10 kLoC of test verifier test cases out into smaller files. Looks like git line counting gets a little flismy above 16 bit integers, so we need two commits to break up test_verifier. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 7 年前 | |
selftests/bpf: Fix a test_verifier failure The following test_verifier subtest failed due to new encoding for BSWAP. $ ./test_verifier ... #99/u invalid 64-bit BPF_END FAIL Unexpected success to load! verification time 215 usec stack depth 0 processed 3 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 #99/p invalid 64-bit BPF_END FAIL Unexpected success to load! verification time 198 usec stack depth 0 processed 3 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 Tighten the test so it still reports a failure. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230728011244.3717464-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 2 年前 | |
selftests: bpf: break up test_verifier Break up the first 10 kLoC of test verifier test cases out into smaller files. Looks like git line counting gets a little flismy above 16 bit integers, so we need two commits to break up test_verifier. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 7 年前 | |
selftests/bpf: Fix test_verifier failed test in unprivileged mode Loading the BTF won't be permitted without privileges, hence only test for privileged mode by setting the prog type. This makes the test_verifier show 0 failures when unprivileged BPF is enabled. Fixes: 41188e9e9def ("selftest/bpf: Test for use-after-free bug fix in inline_bpf_loop") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20220721134245.2450-14-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 3 年前 | |
selftests/bpf: check if BPF_ST with variable offset preserves STACK_ZERO A test case to verify that variable offset BPF_ST instruction preserves STACK_ZERO marks when writes zeros, e.g. in the following situation: *(u64*)(r10 - 8) = 0 ; STACK_ZERO marks for fp[-8] r0 = random(-7, -1) ; some random number in range of [-7, -1] r0 += r10 ; r0 is now variable offset pointer to stack *(u8*)(r0) = 0 ; BPF_ST writing zero, STACK_ZERO mark for ; fp[-8] should be preserved. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20230214232030.1502829-5-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 3 年前 | |
bpf: Fix accesses to uninit stack slots [ Upstream commit 6b4a64bafd107e521c01eec3453ce94a3fb38529 ] Privileged programs are supposed to be able to read uninitialized stack memory (ever since 6715df8d5) but, before this patch, these accesses were permitted inconsistently. In particular, accesses were permitted above state->allocated_stack, but not below it. In other words, if the stack was already "large enough", the access was permitted, but otherwise the access was rejected instead of being allowed to "grow the stack". This undesired rejection was happening in two places: - in check_stack_slot_within_bounds() - in check_stack_range_initialized() This patch arranges for these accesses to be permitted. A bunch of tests that were relying on the old rejection had to change; all of them were changed to add also run unprivileged, in which case the old behavior persists. One tests couldn't be updated - global_func16 - because it can't run unprivileged for other reasons. This patch also fixes the tracking of the stack size for variable-offset reads. This second fix is bundled in the same commit as the first one because they're inter-related. Before this patch, writes to the stack using registers containing a variable offset (as opposed to registers with fixed, known values) were not properly contributing to the function's needed stack size. As a result, it was possible for a program to verify, but then to attempt to read out-of-bounds data at runtime because a too small stack had been allocated for it. Each function tracks the size of the stack it needs in bpf_subprog_info.stack_depth, which is maintained by update_stack_depth(). For regular memory accesses, check_mem_access() was calling update_state_depth() but it was passing in only the fixed part of the offset register, ignoring the variable offset. This was incorrect; the minimum possible value of that register should be used instead. This tracking is now fixed by centralizing the tracking of stack size in grow_stack_state(), and by lifting the calls to grow_stack_state() to check_stack_access_within_bounds() as suggested by Andrii. The code is now simpler and more convincingly tracks the correct maximum stack size. check_stack_range_initialized() can now rely on enough stack having been allocated for the access; this helps with the fix for the first issue. A few tests were changed to also check the stack depth computation. The one that fails without this patch is verifier_var_off:stack_write_priv_vs_unpriv. Fixes: 01f810ace9ed3 ("bpf: Allow variable-offset stack access") Reported-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231208032519.260451-3-andreimatei1@gmail.com Closes: https://lore.kernel.org/bpf/CABWLsev9g8UP_c3a=1qbuZUi20tGoUXoU07FPf-5FLvhOKOY+Q@mail.gmail.com/ Signed-off-by: Sasha Levin <sashal@kernel.org> | 2 年前 | |
selftests/bpf: Add tests for accessing ingress_ifindex in bpf_sk_lookup A new field was added to the bpf_sk_lookup data that users can access. Add tests that validate that the new ingress_ifindex field contains the right data. Signed-off-by: Mark Pashmfouroush <markpash@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211110111016.5670-3-markpash@cloudflare.com | 4 年前 | |
selftests/bpf: Add F_NEEDS_EFFICIENT_UNALIGNED_ACCESS to some tests Some verifier tests were missing F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, which made the test fail. Add the flag where needed. Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230705113926.751791-2-bjorn@kernel.org | 3 年前 | |
selftests, bpf: Test that dead ldx_w insns are accepted Prevent regressions related to zero-extension metadata handling during dead code sanitization. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210812151811.184086-3-iii@linux.ibm.com | 4 年前 | |
selftests/bpf: Mark tests that require unaligned memory access A lot of tests require unaligned memory access to work. Mark the tests as such, so that they can be avoided on unsupported architectures such as RISC-V. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Luke Nelson <luke.r.nels@gmail.com> Link: https://lore.kernel.org/bpf/20201118071640.83773-4-bjorn.topel@gmail.com | 5 年前 | |
selftests/bpf: Fix cgroup sockopt verifier test Since the BPF_PROG_TYPE_CGROUP_SOCKOPT verifier test does not set an attach type, bpf_prog_load_check_attach() disallows loading the program and the test is always skipped: #434/p perfevent for cgroup sockopt SKIP (unsupported program type 25) Fix the issue by setting a valid attach type. Fixes: 0456ea170cd6 ("bpf: Enable more helpers for BPF_PROG_TYPE_CGROUP_{DEVICE,SYSCTL,SOCKOPT}") Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20200710150439.126627-1-jean-philippe@linaro.org | 5 年前 | |
bpf: add selftests for lsh, rsh, arsh with reg operand Current tests cover only shifts with an immediate as the source operand/shift counts; add a new test case to cover register operand. Signed-off-by: Jie Meng <jmeng@fb.com> Link: https://lore.kernel.org/r/20221007202348.1118830-4-jmeng@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 3 年前 | |
selftests/bpf: Add F_NEEDS_EFFICIENT_UNALIGNED_ACCESS to some tests Some verifier tests were missing F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, which made the test fail. Add the flag where needed. Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230705113926.751791-2-bjorn@kernel.org | 3 年前 | |
bpf, selftests: Adjust few selftest outcomes wrt unreachable code In almost all cases from test_verifier that have been changed in here, we've had an unreachable path with a load from a register which has an invalid address on purpose. This was basically to make sure that we never walk this path and to have the verifier complain if it would otherwise. Change it to match on the right error for unprivileged given we now test these paths under speculative execution. There's one case where we match on exact # of insns_processed. Due to the extra path, this will of course mismatch on unprivileged. Thus, restrict the test->insn_processed check to privileged-only. In one other case, we result in a 'pointer comparison prohibited' error. This is similarly due to verifying an 'invalid' branch where we end up with a value pointer on one side of the comparison. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> | 5 年前 | |
bpf, selftests: Add verifier test case for imm=0,umin=0,umax=1 scalar Add a test case to trigger the constant scalar issue which leaves the register in scalar(imm=0,umin=0,umax=1,var_off=(0x0; 0x0)) state. Make use of dead code elimination, so that we can see the verifier bailing out on unfixed kernels. For the condition, we use jle given it checks on umax bound. Before: # ./test_verifier 743 #743/p jump & dead code elimination FAIL Failed to load prog 'Permission denied'! R4 !read_ok verification time 11 usec stack depth 0 processed 13 insns (limit 1000000) max_states_per_insn 0 total_states 1 peak_states 1 mark_read 1 Summary: 0 PASSED, 0 SKIPPED, 1 FAILED After: # ./test_verifier 743 #743/p jump & dead code elimination OK Summary: 1 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220701124727.11153-3-daniel@iogearbox.net | 4 年前 | |
selftests: bpf: break up test_verifier Break up the first 10 kLoC of test verifier test cases out into smaller files. Looks like git line counting gets a little flismy above 16 bit integers, so we need two commits to break up test_verifier. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 7 年前 | |
selftests: bpf: break up the rest of test_verifier Break up the rest of test_verifier tests into separate files. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 7 年前 | |
selftests/bpf: synthetic tests to push verifier limits Add a test to generate 1m ld_imm64 insns to stress the verifier. Bump the size of fill_ld_abs_vlan_push_pop test from 4k to 29k and jump_around_ld_abs from 4k to 5.5k. Larger sizes are not possible due to 16-bit offset encoding in jump instructions. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> | 7 年前 | |
bpf: handle ldimm64 properly in check_cfg() [ Upstream commit 3feb263bb516ee7e1da0acd22b15afbb9a7daa19 ] ldimm64 instructions are 16-byte long, and so have to be handled appropriately in check_cfg(), just like the rest of BPF verifier does. This has implications in three places: - when determining next instruction for non-jump instructions; - when determining next instruction for callback address ldimm64 instructions (in visit_func_call_insn()); - when checking for unreachable instructions, where second half of ldimm64 is expected to be unreachable; We take this also as an opportunity to report jump into the middle of ldimm64. And adjust few test_verifier tests accordingly. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Reported-by: Hao Sun <sunhao.th@gmail.com> Fixes: 475fb78fbf48 ("bpf: verifier (add branch/goto checks)") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231110002638.4168352-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> | 2 年前 | |
selftests/bpf: Add F_NEEDS_EFFICIENT_UNALIGNED_ACCESS to some tests Some verifier tests were missing F_NEEDS_EFFICIENT_UNALIGNED_ACCESS, which made the test fail. Add the flag where needed. Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20230705113926.751791-2-bjorn@kernel.org | 3 年前 | |
selftests/bpf: Use __BYTE_ORDER__ Use the compiler-defined __BYTE_ORDER__ instead of the libc-defined __BYTE_ORDER for consistency. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211026010831.748682-4-iii@linux.ibm.com | 4 年前 | |
bpf: Remove mark_precise_scalar_ids() [ Upstream commit 842edb5507a1038e009d27e69d13b94b6f085763 ] Function mark_precise_scalar_ids() is superseded by bt_sync_linked_regs() and equal scalars tracking in jump history. mark_precise_scalar_ids() propagates precision over registers sharing same ID on parent/child state boundaries, while jump history records allow bt_sync_linked_regs() to propagate same information with instruction level granularity, which is strictly more precise. This commit removes mark_precise_scalar_ids() and updates test cases in progs/verifier_scalar_ids to reflect new verifier behavior. The tests are updated in the following manner: - mark_precise_scalar_ids() propagated precision regardless of presence of conditional jumps, while new jump history based logic only kicks in when conditional jumps are present. Hence test cases are augmented with conditional jumps to still trigger precision propagation. - As equal scalars tracking no longer relies on parent/child state boundaries some test cases are no longer interesting, such test cases are removed, namely: - precision_same_state and precision_cross_state are superseded by linked_regs_bpf_k; - precision_same_state_broken_link and equal_scalars_broken_link are superseded by linked_regs_broken_link. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240718202357.1746514-3-eddyz87@gmail.com [ zhenzhong: backport to 6.6.y after adapting the first linked-regs history commit to the older scalar-id verifier layout. ] Signed-off-by: Zhenzhong Wu <jt26wzz@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> (cherry picked from commit 78da8e1be90c51d260cfb4442362bb3c9c4b49c9) Signed-off-by: Wentao Guan <guanwentao@uniontech.com> | 1 个月前 | |
selftests/bpf: two scale tests Add two tests to check that sequence of 1024 jumps is verifiable. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> | 7 年前 | |
bpf: Allow BPF_PROG_TYPE_STRUCT_OPS programs to be sleepable BPF struct_ops programs currently cannot be marked as sleepable. This need not be the case -- struct_ops programs can be sleepable, and e.g. invoke kfuncs that export the KF_SLEEPABLE flag. So as to allow future struct_ops programs to invoke such kfuncs, this patch updates the verifier to allow struct_ops programs to be sleepable. A follow-on patch will add support to libbpf for specifying struct_ops.s as a sleepable struct_ops program, and then another patch will add testcases to the dummy_st_ops selftest suite which test sleepable struct_ops behavior. Signed-off-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20230125164735.785732-2-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> | 3 年前 | |
selftests/bpf: Mark tests that require unaligned memory access A lot of tests require unaligned memory access to work. Mark the tests as such, so that they can be avoided on unsupported architectures such as RISC-V. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Luke Nelson <luke.r.nels@gmail.com> Link: https://lore.kernel.org/bpf/20201118071640.83773-4-bjorn.topel@gmail.com | 5 年前 |