bpf: Fix ref_obj_id for dynptr data slices in verifier
When a data slice is obtained from a dynptr (through the bpf_dynptr_data API), the ref obj id of the dynptr must be found and then associated with the data slice. The ref obj id of the dynptr must be found *before* the caller saved regs are reset. Without this fix, the ref obj id tracking is not correct for dynptrs that are at an offset from the frame pointer. Please also note that the data slice's ref obj id must be assigned after the ret types are parsed, since RET_PTR_TO_ALLOC_MEM-type return regs get zero-marked. Fixes: 34d4ef57 ("bpf: Add dynptr data slices") Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Acked-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20220809214055.4050604-1-joannelkoong@gmail.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>
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