From: Kumar Kartikeya Dwivedi memxor@gmail.com
commit 13c6a37d409db9abc9c0bfc6d0a2f07bf0fff60e upstream.
This test tries to pass a PTR_TO_BTF_ID_OR_NULL to the release function, which would trigger a out of bounds access without the fix in commit 45ce4b4f9009 ("bpf: Fix crash due to out of bounds access into reg2btf_ids.") but after the fix, it should only index using base_type(reg->type), which should be less than __BPF_REG_TYPE_MAX, and also not permit any type flags to be set for the reg->type.
Signed-off-by: Kumar Kartikeya Dwivedi memxor@gmail.com Signed-off-by: Alexei Starovoitov ast@kernel.org Link: https://lore.kernel.org/bpf/20220220023138.2224652-1-memxor@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/testing/selftests/bpf/verifier/calls.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
--- a/tools/testing/selftests/bpf/verifier/calls.c +++ b/tools/testing/selftests/bpf/verifier/calls.c @@ -108,6 +108,25 @@ .errstr = "R0 min value is outside of the allowed memory range", }, { + "calls: trigger reg2btf_ids[reg->type] for reg->type > __BPF_REG_TYPE_MAX", + .insns = { + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8), + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = REJECT, + .errstr = "arg#0 pointer type STRUCT prog_test_ref_kfunc must point", + .fixup_kfunc_btf_id = { + { "bpf_kfunc_call_test_acquire", 3 }, + { "bpf_kfunc_call_test_release", 5 }, + }, +}, +{ "calls: overlapping caller/callee", .insns = { BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 0),