From nobody Wed Jan 19 11:56:00 2022 From: Sergei Trofimovich To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, Sergei Trofimovich , Josh Poimboeuf Subject: [PATCH] objtool: check: give big enough buffer for pv_ops Date: Fri, 14 Jan 2022 07:57:56 +0000 Message-Id: <20220114075756.838243-1-slyich@gmail.com> List-ID: X-Mailing-List: linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit On gcc-12 build fails flagging possible buffer overflow: check.c: In function 'validate_call': check.c:2865:58: error: '%d' directive output may be truncated writing between 1 and 10 bytes into a region of size 9 [-Werror=format-truncation=] 2865 | snprintf(pvname, sizeof(pvname), "pv_ops[%d]", idx); | ^~ I think it's a valid warning: static char pvname[16]; int idx; ... idx = (rel->addend / sizeof(void *)); snprintf(pvname, sizeof(pvname), "pv_ops[%d]", idx); we have only 7 chars for %d while it could take up to 9. CC: Josh Poimboeuf CC: Peter Zijlstra --- tools/objtool/check.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 8c1931eab5f1..0fae132ea59f 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2852,7 +2852,7 @@ static inline bool func_uaccess_safe(struct symbol *func) static inline const char *call_dest_name(struct instruction *insn) { - static char pvname[16]; + static char pvname[32]; struct reloc *rel; int idx; -- 2.34.1