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| author | Peter Zijlstra <peterz@infradead.org> | 2020-06-03 20:09:06 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-06-15 14:10:09 +0200 |
| commit | 6b643a07a7e41f9e11cfbb9bba4c5c9791ac2997 (patch) | |
| tree | 6d273e16bc0f0d0e72f0036144882300c7986f98 /tools/objtool | |
| parent | x86/entry, cpumask: Provide non-instrumented variant of cpu_is_offline() (diff) | |
| download | linux-6b643a07a7e41f9e11cfbb9bba4c5c9791ac2997.tar.xz linux-6b643a07a7e41f9e11cfbb9bba4c5c9791ac2997.zip | |
x86/entry, ubsan, objtool: Whitelist __ubsan_handle_*()
The UBSAN instrumentation only inserts external CALLs when things go
'BAD', much like WARN(). So treat them similar to WARN()s for noinstr,
that is: allow them, at the risk of taking the machine down, to get
their message out.
Suggested-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Marco Elver <elver@google.com>
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/check.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 5fbb90a80d23..3e214f879ada 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2190,10 +2190,36 @@ static inline const char *call_dest_name(struct instruction *insn) return "{dynamic}"; } +static inline bool noinstr_call_dest(struct symbol *func) +{ + /* + * We can't deal with indirect function calls at present; + * assume they're instrumented. + */ + if (!func) + return false; + + /* + * If the symbol is from a noinstr section; we good. + */ + if (func->sec->noinstr) + return true; + + /* + * The __ubsan_handle_*() calls are like WARN(), they only happen when + * something 'BAD' happened. At the risk of taking the machine down, + * let them proceed to get the message out. + */ + if (!strncmp(func->name, "__ubsan_handle_", 15)) + return true; + + return false; +} + static int validate_call(struct instruction *insn, struct insn_state *state) { if (state->noinstr && state->instr <= 0 && - (!insn->call_dest || !insn->call_dest->sec->noinstr)) { + !noinstr_call_dest(insn->call_dest)) { WARN_FUNC("call to %s() leaves .noinstr.text section", insn->sec, insn->offset, call_dest_name(insn)); return 1; |