From 988f01683c7f2bf9f8fe2bae1cf4010fcd1baaf5 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 2 Dec 2021 21:45:34 +0100 Subject: objtool: Fix pv_ops noinstr validation Boris reported that in one of his randconfig builds, objtool got infinitely stuck. Turns out there's trivial list corruption in the pv_ops tracking when a function is both in a static table and in a code assignment. Avoid re-adding function to the pv_ops[] lists when they're already on it. Fixes: db2b0c5d7b6f ("objtool: Support pv_opsindirect calls for noinstr") Reported-by: Borislav Petkov Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Tested-by: Borislav Petkov Link: https://lkml.kernel.org/r/20211202204534.GA16608@worktop.programming.kicks-ass.net --- tools/objtool/elf.c | 1 + tools/objtool/objtool.c | 4 ++++ 2 files changed, 5 insertions(+) (limited to 'tools/objtool') diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index 81a4c543ff7e..4b384c907027 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -375,6 +375,7 @@ static int read_symbols(struct elf *elf) return -1; } memset(sym, 0, sizeof(*sym)); + INIT_LIST_HEAD(&sym->pv_target); sym->alias = sym; sym->idx = i; diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c index c90c7084e45a..bdf699f6552b 100644 --- a/tools/objtool/objtool.c +++ b/tools/objtool/objtool.c @@ -153,6 +153,10 @@ void objtool_pv_add(struct objtool_file *f, int idx, struct symbol *func) !strcmp(func->name, "_paravirt_ident_64")) return; + /* already added this function */ + if (!list_empty(&func->pv_target)) + return; + list_add(&func->pv_target, &f->pv_ops[idx].targets); f->pv_ops[idx].clean = false; } -- cgit v1.2.3-59-g8ed1b