From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1944) id A23823852C51; Wed, 23 Nov 2022 14:38:55 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A23823852C51 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1669214335; bh=3SSp4EgskImUCUjoEceEoJ3LxV4k1dVvyxMj/xBy3Gk=; h=From:To:Subject:Date:From; b=fBsIvHHjFJI+HJs6avInCkY8q484AoE/4m0F9apKYhBu/VrokPkSe8pLUkky44kMs Y70NrFhgc89GXEj9eADmJkfF+LWlqIA1SQpsQvZ/ledKCiJMevtAA4NfWtysSBQfu8 oNN8cMbGvsDTCX6Lm3f74ehGP2yNqKzC6bdbhm2E= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Szabolcs Nagy To: glibc-cvs@sourceware.org Subject: [glibc/arm/morello/main] Fix invalid pointer dereference in wcscpy_chk X-Act-Checkin: glibc X-Git-Author: Szabolcs Nagy X-Git-Refname: refs/heads/arm/morello/main X-Git-Oldrev: c505926c319b9ab6e849664968cb722c35acaf88 X-Git-Newrev: aecfbacba2bd14eebeeb1da5b303385a9d2992a2 Message-Id: <20221123143855.A23823852C51@sourceware.org> Date: Wed, 23 Nov 2022 14:38:55 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=aecfbacba2bd14eebeeb1da5b303385a9d2992a2 commit aecfbacba2bd14eebeeb1da5b303385a9d2992a2 Author: Szabolcs Nagy Date: Tue Jun 21 14:43:30 2022 +0100 Fix invalid pointer dereference in wcscpy_chk The src pointer is const and points to a different object, so accessing dest via src is invalid. Diff: --- debug/wcscpy_chk.c | 34 +++++++--------------------------- 1 file changed, 7 insertions(+), 27 deletions(-) diff --git a/debug/wcscpy_chk.c b/debug/wcscpy_chk.c index 8ef03f81e4..d2dc769181 100644 --- a/debug/wcscpy_chk.c +++ b/debug/wcscpy_chk.c @@ -24,36 +24,16 @@ wchar_t * __wcscpy_chk (wchar_t *dest, const wchar_t *src, size_t n) { wint_t c; - wchar_t *wcp; + wchar_t *wcp = dest; - if (__alignof__ (wchar_t) >= sizeof (wchar_t)) + do { - const ptrdiff_t off = dest - src - 1; - - wcp = (wchar_t *) src; - - do - { - if (__glibc_unlikely (n-- == 0)) - __chk_fail (); - c = *wcp++; - wcp[off] = c; - } - while (c != L'\0'); - } - else - { - wcp = dest; - - do - { - if (__glibc_unlikely (n-- == 0)) - __chk_fail (); - c = *src++; - *wcp++ = c; - } - while (c != L'\0'); + if (__glibc_unlikely (n-- == 0)) + __chk_fail (); + c = *src++; + *wcp++ = c; } + while (c != L'\0'); return dest; }