perf dwarf-aux: Bound the type chases for broken debug info

A DIE parsed at an offset that is not the start of a DIE can have a
DW_AT_type that refers back to itself, making the typedef/qualifier
chases in die_get_real_type(), die_get_pointer_type() and
die_get_typename_from_type() spin forever; 'perf report -s type' did
that on the dwz compressed debug info of zlib-ng (libz.so.1).

No sane typedef/qualifier chain is 32 DIEs long, so give up on the type
with a pr_debug instead of hanging.

Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Assisted-by: LLM
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

0 files changed, 0 insertions, 0 deletions