Message ID | 20201111031213.25109-1-alexei.starovoitov@gmail.com (mailing list archive) |
---|---|
Headers | show |
Series | bpf: Pointers beyond packet end. | expand |
Hello: This series was applied to bpf/bpf-next.git (refs/heads/master): On Tue, 10 Nov 2020 19:12:10 -0800 you wrote: > From: Alexei Starovoitov <ast@kernel.org> > > v1->v2: > - removed set-but-unused variable. > - added Jiri's Tested-by. > > In some cases LLVM uses the knowledge that branch is taken to optimze the code > which causes the verifier to reject valid programs. > Teach the verifier to recognize that > r1 = skb->data; > r1 += 10; > r2 = skb->data_end; > if (r1 > r2) { > here r1 points beyond packet_end and subsequent > if (r1 > r2) // always evaluates to "true". > } > > [...] Here is the summary with links: - [v2,bpf-next,1/3] bpf: Support for pointers beyond pkt_end. https://git.kernel.org/bpf/bpf-next/c/6d94e741a8ff - [v2,bpf-next,2/3] selftests/bpf: Add skb_pkt_end test https://git.kernel.org/bpf/bpf-next/c/9cc873e85800 - [v2,bpf-next,3/3] selftests/bpf: Add asm tests for pkt vs pkt_end comparison. https://git.kernel.org/bpf/bpf-next/c/cb62d34019d9 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
From: Alexei Starovoitov <ast@kernel.org> v1->v2: - removed set-but-unused variable. - added Jiri's Tested-by. In some cases LLVM uses the knowledge that branch is taken to optimze the code which causes the verifier to reject valid programs. Teach the verifier to recognize that r1 = skb->data; r1 += 10; r2 = skb->data_end; if (r1 > r2) { here r1 points beyond packet_end and subsequent if (r1 > r2) // always evaluates to "true". } Alexei Starovoitov (3): bpf: Support for pointers beyond pkt_end. selftests/bpf: Add skb_pkt_end test selftests/bpf: Add asm tests for pkt vs pkt_end comparison. include/linux/bpf_verifier.h | 2 +- kernel/bpf/verifier.c | 129 +++++++++++++++--- .../bpf/prog_tests/test_skb_pkt_end.c | 41 ++++++ .../testing/selftests/bpf/progs/skb_pkt_end.c | 54 ++++++++ .../testing/selftests/bpf/verifier/ctx_skb.c | 42 ++++++ 5 files changed, 245 insertions(+), 23 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/test_skb_pkt_end.c create mode 100644 tools/testing/selftests/bpf/progs/skb_pkt_end.c