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bpf_convert_ctx_accesses() turns a BPF_LDX into a BPF_PROBE_MEM one by matching the type recorded for the insn against a list of exact pointer types. The list cannot keep up with the flag combinations the verifier produces, and a type which is missing from it ends up as a plain load without an exception table entry, so a bad address panics the kernel instead of being handled. Two such types exist today and are reachable: - PTR_TO_BTF_ID | PTR_UNTRUSTED | MEM_ALLOC | NON_OWN_REF - PTR_TO_BTF_ID | PTR_UNTRUSTED | MEM_RCU Rather than adding the two, just drop the list and state the property itself in the default case of the switch. This is a superset of what the list matched, the untrusted PTR_TO_MEM does not have to carry MEM_RDONLY for it anymore, and it stays in sync with the verifier side which uses the same match in save_aux_ptr_type() and reg_type_mismatch_ok(). Assert that a fault prone type which does not get the rewrite for whatever reason is rejected at load time rather than left to fault at runtime to catch any future cases. Fixes:1b12171533("bpf: Mark direct ld of stashed bpf_{rb,list}_node as non-owning ref") Fixes:6fcd486b3a("bpf: Refactor RCU enforcement in the verifier.") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260814215301.709827-4-daniel@iogearbox.net