Maxim Mikityanskiy 2fa7d94afc bpf: Fix the off-by-two error in range markings ... The first commit cited below attempts to fix the off-by-one error that appeared in some comparisons with an open range. Due to this error, arithmetically equivalent pieces of code could get different verdicts from the verifier, for example (pseudocode): // 1. Passes the verifier: if (data + 8 > data_end) return early read *(u64 *)data, i.e. [data; data+7] // 2. Rejected by the verifier (should still pass): if (data + 7 >= data_end) return early read *(u64 *)data, i.e. [data; data+7] The attempted fix, however, shifts the range by one in a wrong direction, so the bug not only remains, but also such piece of code starts failing in the verifier: // 3. Rejected by the verifier, but the check is stricter than in #1. if (data + 8 >= data_end) return early read *(u64 *)data, i.e. [data; data+7] The change performed by that fix converted an off-by-one bug into off-by-two. The second commit cited below added the BPF selftests written to ensure than code chunks like #3 are rejected, however, they should be accepted. This commit fixes the off-by-two error by adjusting new_range in the right direction and fixes the tests by changing the range into the one that should actually fail. Fixes: fb2a311a31 ("bpf: fix off by one for range markings with L{T, E} patterns") Fixes: b37242c773 ("bpf: add test cases to bpf selftests to cover all access tests") Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20211130181607.593149-1-maximmi@nvidia.com		2021-12-03 21:44:42 +01:00
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cxl	tools/testing/cxl: Introduce a mock memory device + driver	2021-09-21 14:09:34 -07:00
fault-injection
ktest	bootconfig/tracing/ktest: Update ktest example for boot-time tracing	2021-08-16 11:39:51 -04:00
kunit	kunit: tool: fix typecheck errors about loading qemu configs	2021-10-29 13:05:47 -06:00
nvdimm	tools/testing/nvdimm: Fix missing 'fallthrough' warning	2021-08-11 11:55:54 -07:00
radix-tree	idr test suite: Improve reporting from idr_find_test_1	2021-04-01 07:50:42 -04:00
scatterlist	Merge branch 'akpm' (patches from Andrew)	2021-09-03 10:08:28 -07:00
selftests	bpf: Fix the off-by-two error in range markings	2021-12-03 21:44:42 +01:00
vsock	vsock_diag_test: remove free_sock_stat() call in test_no_sockets	2021-10-15 17:21:34 -07:00