From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 944BE384404C; Wed, 23 Sep 2020 11:57:05 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 944BE384404C From: "xiechengliang1 at huawei dot com" To: glibc-bugs@sourceware.org Subject: [Bug libc/26657] New: strncpy in login/login.c line 114 might leave the destination string unterminate Date: Wed, 23 Sep 2020 11:57:05 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: libc X-Bugzilla-Version: 2.31 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: xiechengliang1 at huawei dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter cc target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: glibc-bugs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Glibc-bugs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 Sep 2020 11:57:05 -0000 https://sourceware.org/bugzilla/show_bug.cgi?id=3D26657 Bug ID: 26657 Summary: strncpy in login/login.c line 114 might leave the destination string unterminate Product: glibc Version: 2.31 Status: UNCONFIRMED Severity: normal Priority: P2 Component: libc Assignee: unassigned at sourceware dot org Reporter: xiechengliang1 at huawei dot com CC: drepper.fsp at gmail dot com Target Milestone: --- The glibc-2.31/login/login.c 114 line contains the following code: strncpy (copy.ut_line, ttyp, UT_LINESIZE); The UT_LINESIZE size is 32 bytes=EF=BC=8Cand the size of the destination = array "copy.ut_line" is also 32 bytes. The code cannot ensure that the "ttyp" ends with '\0'. so calling "strncpy" might leave the destination string unterminated. When strlen is used to obtain the length of the "copy.ut_line" array, a buffer overflow occurs. Consider setting the 32nd bit of the "copy.ut_line" array to '\0' to fix = it. --=20 You are receiving this mail because: You are on the CC list for the bug.=