bpf: fix sanitation of alu op with pointer / scalar type from different paths
commit d3bd7413 upstream. While 979d63d5 ("bpf: prevent out of bounds speculation on pointer arithmetic") took care of rejecting alu op on pointer when e.g. pointer came from two different map values with different map properties such as value size, Jann reported that a case was not covered yet when a given alu op is used in both "ptr_reg += reg" and "numeric_reg += reg" from different branches where we would incorrectly try to sanitize based on the pointer's limit. Catch this corner case and reject the program instead. Fixes: 979d63d5 ("bpf: prevent out of bounds speculation on pointer arithmetic") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Vallish Vaidyeshwara <vallish@amazon.com> Signed-off-by: Balbir Singh <sblbir@amzn.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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