From unknown Sun Aug 17 01:52:07 2025 X-Loop: help-debbugs@gnu.org Subject: bug#32249: [BUGFIX] cmp -b mangles result Resent-From: mancha Original-Sender: "Debbugs-submit" Resent-CC: bug-diffutils@gnu.org Resent-Date: Mon, 23 Jul 2018 15:42:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: report 32249 X-GNU-PR-Package: diffutils X-GNU-PR-Keywords: To: 32249@debbugs.gnu.org X-Debbugs-Original-To: bug-diffutils@gnu.org Received: via spool by submit@debbugs.gnu.org id=B.153236049527077 (code B ref -1); Mon, 23 Jul 2018 15:42:02 +0000 Received: (at submit) by debbugs.gnu.org; 23 Jul 2018 15:41:35 +0000 Received: from localhost ([127.0.0.1]:54246 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fhcxr-00072f-AA for submit@debbugs.gnu.org; Mon, 23 Jul 2018 11:41:35 -0400 Received: from eggs.gnu.org ([208.118.235.92]:52341) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fhYEA-00045D-FO for submit@debbugs.gnu.org; Mon, 23 Jul 2018 06:38:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fhYE4-0001iw-GL for submit@debbugs.gnu.org; Mon, 23 Jul 2018 06:38:01 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=-1.6 required=5.0 tests=BAYES_00, FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:40230) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fhYE4-0001iq-Bj for submit@debbugs.gnu.org; Mon, 23 Jul 2018 06:38:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43307) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fhYE3-0003xY-6c for bug-diffutils@gnu.org; Mon, 23 Jul 2018 06:38:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fhYDz-0001gr-W6 for bug-diffutils@gnu.org; Mon, 23 Jul 2018 06:37:59 -0400 Received: from sender-pp-092.zoho.com ([135.84.80.237]:25483) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fhYDz-0001dk-K4 for bug-diffutils@gnu.org; Mon, 23 Jul 2018 06:37:55 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=zapps768; d=zoho.com; h=date:from:to:subject:message-id:mime-version:content-type; b=eJ8iTRBFmE4EnY+/XUAuprATuLcD8ABXB3E3F8a3wFiE5DA/bB6QqNsmb6CC4FjQMRpVHCI/Cf3v ReYVMgtzkTgV6If6Kqml3yMq/umVF5O3Bfm5aXLxi9xqeN5/ZkVW Received: from zoho.com (62-210-71-205.rev.poneytelecom.eu [62.210.71.205]) by mx.zohomail.com with SMTPS id 1532328720605878.1756695954514; Sun, 22 Jul 2018 23:52:00 -0700 (PDT) Date: Mon, 23 Jul 2018 06:48:26 +0000 From: mancha Message-ID: <20180723064826.GA32585@zoho.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="yVhtmJPUSI46BTXb" Content-Disposition: inline X-PGP-Key: http://hkps.pool.sks-keyservers.net/pks/lookup?op=vindex&search=0x25168eb24f0b22ac X-PGP-FP: 56B7 100E F4D5 811C 8FEF ADD1 2516 8EB2 4F0B 22AC X-Zoho-Virus-Status: 1 X-ZohoMailClient: External X-ZohoMail: Z_29226335 SPT_1 SLF_E S_168 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 2001:4830:134:3::11 X-Spam-Score: -3.8 (---) X-Mailman-Approved-At: Mon, 23 Jul 2018 11:41:34 -0400 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -4.8 (----) --yVhtmJPUSI46BTXb Content-Type: multipart/mixed; boundary="aVD9QWMuhilNxW9f" Content-Disposition: inline --aVD9QWMuhilNxW9f Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi. count_newlines is passed the wrong buffer length (off-by-one) so it overwrites first differing byte in first file's buffer. Attached patch fixes. Actual: $ cmp -b <(echo bad) <(echo bug) [snip] differ: byte 2, line 1 is 12 ^J 165 u Expected: $ cmp -b <(echo bad) <(echo bug) [snip] differ: byte 2, line 1 is 141 a 165 u Cheers! --mancha --aVD9QWMuhilNxW9f Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="cmp-newlines.patch" Content-Transfer-Encoding: quoted-printable --- a/src/cmp.c +++ b/src/cmp.c @@ -466,7 +466,7 @@ cmp (void) byte_number +=3D first_diff; if (comparison_type =3D=3D type_first_diff && first_diff !=3D 0) { - line_number +=3D count_newlines (buf0, first_diff); + line_number +=3D count_newlines (buf0, first_diff + 1); at_line_start =3D buf0[first_diff - 1] =3D=3D '\n'; } =20 --aVD9QWMuhilNxW9f-- --yVhtmJPUSI46BTXb Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJbVXo6AAoJEKPZDStQM/UXz0MQAIFKN4wueNRKH/Bs1A25E2BO b6aAG6beIUXvCJqd1LpDvfHNYeUdzx9pv/MFaoRSkk1WvTgv4BcUuJt7P4E3wOsc 53Bnw98JqAfPyFggBEW0uLjXUVdllnbl6WD6kVy+Zyd9DcnmgCuy/X1MGPQcl1+U JYoRItfCYjPFQPi4gdBTEA+2jqm4X/j0Azkdu6sZpAT28rcO8SQ5KgtJZrNgwwQY 7QkIgYp9+PynpJVgw3Oxe0RQ4fZC1VA+g7qVbH1rxQOZONETpJ7vBbfg7M3cVxp7 XMCQTgh3vn8uHSAOv7Ib/sWC047RxrEoxGAVE+h76v4ey+nM51GgaRRGd8fgbtES j6tdeElinMgTA+I2haghhp3Cq89wHOBmOPLP7pbmZJMqF1Rex9z+P8AIzj0ErNC8 JuNWl6U+lHg7txkjIhGtZJuhA2x1V3YmLlC/HGifbTX0xNyFxd4WG86Z5XYhj4WJ l53BM9ssb8H04KhetUQ5F1RRyCBXyVxFSdIWvdmbcGRS/iSLzTIVdfmWF+2qHEpQ fDfyCcIoLfIapETbe6UEyjur5GNZ8rcKqj8msR8D1UWh82uZUEAzYweYzSAVw+fs Y8Br05YUoLY2NZFjoJNgDC1mRz5SZlWduhbI2c0YbMYjo7NjSPLerc/srfH+4JDb LwY9LH9i1PKD9CYxjixy =amlv -----END PGP SIGNATURE----- --yVhtmJPUSI46BTXb-- From unknown Sun Aug 17 01:52:07 2025 MIME-Version: 1.0 X-Mailer: MIME-tools 5.505 (Entity 5.505) X-Loop: help-debbugs@gnu.org From: help-debbugs@gnu.org (GNU bug Tracking System) To: mancha Subject: bug#32249: closed (Re: [bug-diffutils] bug#32249: [BUGFIX] cmp -b mangles result) Message-ID: References: <20180723064826.GA32585@zoho.com> X-Gnu-PR-Message: they-closed 32249 X-Gnu-PR-Package: diffutils Reply-To: 32249@debbugs.gnu.org Date: Tue, 24 Jul 2018 17:21:02 +0000 Content-Type: multipart/mixed; boundary="----------=_1532452862-13087-1" This is a multi-part message in MIME format... ------------=_1532452862-13087-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Your bug report #32249: [BUGFIX] cmp -b mangles result which was filed against the diffutils package, has been closed. The explanation is attached below, along with your original report. If you require more details, please reply to 32249@debbugs.gnu.org. --=20 32249: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=3D32249 GNU Bug Tracking System Contact help-debbugs@gnu.org with problems ------------=_1532452862-13087-1 Content-Type: message/rfc822 Content-Disposition: inline Content-Transfer-Encoding: 7bit Received: (at 32249-done) by debbugs.gnu.org; 24 Jul 2018 17:20:30 +0000 Received: from localhost ([127.0.0.1]:55723 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fi0z7-0003O8-Op for submit@debbugs.gnu.org; Tue, 24 Jul 2018 13:20:30 -0400 Received: from zimbra.cs.ucla.edu ([131.179.128.68]:37996) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fi0z6-0003Nv-3Y for 32249-done@debbugs.gnu.org; Tue, 24 Jul 2018 13:20:28 -0400 Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 424BB161170; Tue, 24 Jul 2018 10:20:22 -0700 (PDT) Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id 61tlNOjO8wqd; Tue, 24 Jul 2018 10:20:21 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 7079D16124C; Tue, 24 Jul 2018 10:20:21 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id yBRY3Wm1FfQj; Tue, 24 Jul 2018 10:20:21 -0700 (PDT) Received: from Penguin.CS.UCLA.EDU (Penguin.CS.UCLA.EDU [131.179.64.200]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 5464C161170; Tue, 24 Jul 2018 10:20:21 -0700 (PDT) Subject: Re: [bug-diffutils] bug#32249: [BUGFIX] cmp -b mangles result To: mancha , 32249-done@debbugs.gnu.org References: <20180723064826.GA32585@zoho.com> From: Paul Eggert Openpgp: preference=signencrypt Autocrypt: addr=eggert@cs.ucla.edu; prefer-encrypt=mutual; keydata= xsFNBEyAcmQBEADAAyH2xoTu7ppG5D3a8FMZEon74dCvc4+q1XA2J2tBy2pwaTqfhpxxdGA9 Jj50UJ3PD4bSUEgN8tLZ0san47l5XTAFLi2456ciSl5m8sKaHlGdt9XmAAtmXqeZVIYX/UFS 96fDzf4xhEmm/y7LbYEPQdUdxu47xA5KhTYp5bltF3WYDz1Ygd7gx07Auwp7iw7eNvnoDTAl KAl8KYDZzbDNCQGEbpY3efZIvPdeI+FWQN4W+kghy+P6au6PrIIhYraeua7XDdb2LS1en3Ss mE3QjqfRqI/A2ue8JMwsvXe/WK38Ezs6x74iTaqI3AFH6ilAhDqpMnd/msSESNFt76DiO1ZK QMr9amVPknjfPmJISqdhgB1DlEdw34sROf6V8mZw0xfqT6PKE46LcFefzs0kbg4GORf8vjG2 Sf1tk5eU8MBiyN/bZ03bKNjNYMpODDQQwuP84kYLkX2wBxxMAhBxwbDVZudzxDZJ1C2VXujC OJVxq2kljBM9ETYuUGqd75AW2LXrLw6+MuIsHFAYAgRr7+KcwDgBAfwhPBYX34nSSiHlmLC+ KaHLeCLF5ZI2vKm3HEeCTtlOg7xZEONgwzL+fdKo+D6SoC8RRxJKs8a3sVfI4t6CnrQzvJbB n6gxdgCu5i29J1QCYrCYvql2UyFPAK+do99/1jOXT4m2836j1wARAQABzSBQYXVsIEVnZ2Vy dCA8ZWdnZXJ0QGNzLnVjbGEuZWR1PsLBfgQTAQIAKAUCTIByZAIbAwUJEswDAAYLCQgHAwIG FQgCCQoLBBYCAwECHgECF4AACgkQ7ZfpDmKqfjRRGw/+Ij03dhYfYl/gXVRiuzV1gGrbHk+t nfrI/C7fAeoFzQ5tVgVinShaPkZo0HTPf18x6IDEdAiO8Mqo1yp0CtHmzGMCJ50o4Grgfjlr 6g/+vtEOKbhleszN2XpJvpwM2QgGvn/laTLUu8PH9aRWTs7qJJZKKKAb4sxYc92FehPu6FOD 0dDiyhlDAq4lOV2mdBpzQbiojoZzQLMQwjpgCTK2572eK9EOEQySUThXrSIz6ASenp4NYTFH s9tuJQvXk9gZDdPSl3bp+47dGxlxEWLpBIM7zIONw4ks4azgT8nvDZxA5IZHtvqBlJLBObYY 0Le61Wp0y3TlBDh2qdK8eYL426W4scEMSuig5gb8OAtQiBW6k2sGUxxeiv8ovWu8YAZgKJfu oWI+uRnMEddruY8JsoM54KaKvZikkKs2bg1ndtLVzHpJ6qFZC7QVjeHUh6/BmgvdjWPZYFTt N+KA9CWX3GQKKgN3uu988yznD7LnB98T4EUH1HA/GnfBqMV1gpzTvPc4qVQinCmIkEFp83zl +G5fCjJJ3W7ivzCnYo4KhKLpFUm97okTKR2LW3xZzEW4cLSWO387MTK3CzDOx5qe6s4a91Zu ZM/j/TQdTLDaqNn83kA4Hq48UHXYxcIh+Nd8k/3w6lFuoK0wrOFiywjLx+0ur5jmmbecBGHc 1xdhAFHOwU0ETIByZAEQAKaF678T9wyH4wjTrV1Pz3cDEoSnV/0ZUrOT37p1dcGyj/IXq1x6 70HRVahAmk0sZpYc25PF9D5GPYHFWlNjuPU96rDndXB3hedmBRhLdC4bAXjI4DV+bmdVe+q/ IMnlZRaVlm9EiMCVAR6w13sReu7qXkW9r3RwY2AzXskp/tAe4BRKr1Zmbvi2nbnQ6epEC42r Rbx0B1EhjbIQZ5JHGk24iPT7LdBgnNmos5wYjzwNlkMQD5T0Ydzhk7J+UxwA5m46mOhRDC2r FV/A0gm5TLy8DXjv/Esc4gYnYai6SQqnUEVh5LuV8YCJBnijs+Tiw71x1icmn6xGI45EugJO gec+rLypYgpVp4x0HI5T88qBRYCkxH3Kg8Qo+EWNA9A4LRQ9DX8njona0gf0s03tocK8kBN6 6UoqqPtHBnc4eMgBymCflK12eKfd2YYxnyg9cZazWA5VslvTxpm76hbg5oiAEH/Vg/8MxHyA nPhfrgwyPrmJEcVBafdspJnYQxBYNco2LFPIhlOvWh8r4at+s+M3Lb26oUTczlgdW1Sf3SDA 77BMRnF0FQyE+7AzV79MBN4ykiqaezQxtaF1Fy/tvkhffSo8u+dwG0EgJh+te38gTcISVr0G IPplLz6YhjrbHrPRF1CN5UuL9DBGjxuN35RLNVEfta6RUFlR6NctTjvrABEBAAHCwWUEGAEC AA8FAkyAcmQCGwwFCRLMAwAACgkQ7ZfpDmKqfjSrHA/+KzAKvTxRhA9MWNLxIyJ7S5uJ16gs T3oCjZrBKGEhKMOGX4O0GA6VOEryO7QRCCYah3oxSG38IAnNeiwJXgU9Bzkk85UGbPEd7HGF /VSeHCQwWou6jqUDTSDvn9YhNTdG0KXPM74aC+xr2Zow1O2mhXihgWKD0Dw+0LYPnUOsQ0KO FxHXXYHmRrS1OZPU59BLvc+TRhIhafSHKLwbXK+6ckkxBx6h8z5ccpG0Qs4bFhdFYnFrEieD LoGmnE2YLhdV6swJ9VNCS6pLiEohT3fm7aXm15tZOIyzMZhHRSAPblXxQ0ZSWjq8oRrcYNFx c4W1URpAkBCOYJoXvQfD5L3lqAl8TCqDUzYxhH/tJhbDdHrqHH767jaDaTB1+Talp/2AMKwc XNOdiklGxbmHVG6YGl6g8Lrbsu9NZEI4yLlHzuikthJWgz+3vZhVGyNlt+HNIoF6CjDL2omu 5cEq4RDHM44QqPk6l7O0pUvN1mT4B+S1b08RKpqm/ff015E37HNV/piIvJlxGAYz8PSfuGCB 1thMYqlmgdhd9/BabGFbGGYHA6U4/T5zqU+f6xHy1SsAQZ1MSKlLwekBIT+4/cLRGqCHjnV0 q5H/T6a7t5mPkbzSrOLSo4puj+IToNjYyYIDBWzhlA19avOa+rvUjmHtD3sFN7cXWtkGoi8b uNcby4U= Organization: UCLA Computer Science Department Message-ID: Date: Tue, 24 Jul 2018 10:20:21 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20180723064826.GA32585@zoho.com> Content-Type: multipart/mixed; boundary="------------2E5292ED88F7076146D0B4FA" Content-Language: en-US X-Spam-Score: -2.3 (--) X-Debbugs-Envelope-To: 32249-done X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -3.3 (---) This is a multi-part message in MIME format. --------------2E5292ED88F7076146D0B4FA Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Thanks for the bug report. I suspect that fix won't work in general, though, and I installed the attached fix instead. --------------2E5292ED88F7076146D0B4FA Content-Type: text/x-patch; name="0001-cmp-fix-bug-in-b-diagnostic.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="0001-cmp-fix-bug-in-b-diagnostic.patch" >From 131c2b6b081f5208bdcadae6614866054fc0535b Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Tue, 24 Jul 2018 10:18:28 -0700 Subject: [PATCH] cmp: fix bug in -b diagnostic Problem reported by mancha (Bug#32249). * src/cmp.c (count_newlines): Restore old value of sentinel. * tests/cmp: Test for the bug. --- src/cmp.c | 2 ++ tests/cmp | 10 ++++++++++ 2 files changed, 12 insertions(+) diff --git a/src/cmp.c b/src/cmp.c index 04638e3..2811392 100644 --- a/src/cmp.c +++ b/src/cmp.c @@ -639,9 +639,11 @@ count_newlines (char *buf, size_t bufsize) size_t count = 0; char *p; char *lim = buf + bufsize; + char ch = *lim; *lim = '\n'; for (p = buf; (p = rawmemchr (p, '\n')) != lim; p++) count++; + *lim = ch; return count; } diff --git a/tests/cmp b/tests/cmp index 160c1ea..ca0fe5e 100755 --- a/tests/cmp +++ b/tests/cmp @@ -208,4 +208,14 @@ done >out1 compare exp1 out1 || fail=1 +printf 'bad\n' >bad +printf 'bug\n' >bug +echo LC_ALL=C cmp -b bad bug +LC_ALL=C cmp -b bad bug +test $? -eq 1 || fail=1 +case `LC_ALL=C cmp -b bad bug` in + 'bad bug differ: byte 2, line 1 is '*' a '*' u') ;; + *) echo 'expected cmp -b to report a and u'; fail=1;; +esac + Exit $fail -- 2.17.1 --------------2E5292ED88F7076146D0B4FA-- ------------=_1532452862-13087-1 Content-Type: message/rfc822 Content-Disposition: inline Content-Transfer-Encoding: 7bit Received: (at submit) by debbugs.gnu.org; 23 Jul 2018 15:41:35 +0000 Received: from localhost ([127.0.0.1]:54246 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fhcxr-00072f-AA for submit@debbugs.gnu.org; Mon, 23 Jul 2018 11:41:35 -0400 Received: from eggs.gnu.org ([208.118.235.92]:52341) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fhYEA-00045D-FO for submit@debbugs.gnu.org; Mon, 23 Jul 2018 06:38:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fhYE4-0001iw-GL for submit@debbugs.gnu.org; Mon, 23 Jul 2018 06:38:01 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=-1.6 required=5.0 tests=BAYES_00, FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM autolearn=disabled version=3.3.2 Received: from lists.gnu.org ([2001:4830:134:3::11]:40230) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fhYE4-0001iq-Bj for submit@debbugs.gnu.org; Mon, 23 Jul 2018 06:38:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43307) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fhYE3-0003xY-6c for bug-diffutils@gnu.org; Mon, 23 Jul 2018 06:38:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fhYDz-0001gr-W6 for bug-diffutils@gnu.org; Mon, 23 Jul 2018 06:37:59 -0400 Received: from sender-pp-092.zoho.com ([135.84.80.237]:25483) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fhYDz-0001dk-K4 for bug-diffutils@gnu.org; Mon, 23 Jul 2018 06:37:55 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=zapps768; d=zoho.com; h=date:from:to:subject:message-id:mime-version:content-type; b=eJ8iTRBFmE4EnY+/XUAuprATuLcD8ABXB3E3F8a3wFiE5DA/bB6QqNsmb6CC4FjQMRpVHCI/Cf3v ReYVMgtzkTgV6If6Kqml3yMq/umVF5O3Bfm5aXLxi9xqeN5/ZkVW Received: from zoho.com (62-210-71-205.rev.poneytelecom.eu [62.210.71.205]) by mx.zohomail.com with SMTPS id 1532328720605878.1756695954514; Sun, 22 Jul 2018 23:52:00 -0700 (PDT) Date: Mon, 23 Jul 2018 06:48:26 +0000 From: mancha To: bug-diffutils@gnu.org Subject: [BUGFIX] cmp -b mangles result Message-ID: <20180723064826.GA32585@zoho.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="yVhtmJPUSI46BTXb" Content-Disposition: inline X-PGP-Key: http://hkps.pool.sks-keyservers.net/pks/lookup?op=vindex&search=0x25168eb24f0b22ac X-PGP-FP: 56B7 100E F4D5 811C 8FEF ADD1 2516 8EB2 4F0B 22AC X-Zoho-Virus-Status: 1 X-ZohoMailClient: External X-ZohoMail: Z_29226335 SPT_1 SLF_E S_168 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 2001:4830:134:3::11 X-Spam-Score: -3.8 (---) X-Debbugs-Envelope-To: submit X-Mailman-Approved-At: Mon, 23 Jul 2018 11:41:34 -0400 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -4.8 (----) --yVhtmJPUSI46BTXb Content-Type: multipart/mixed; boundary="aVD9QWMuhilNxW9f" Content-Disposition: inline --aVD9QWMuhilNxW9f Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi. count_newlines is passed the wrong buffer length (off-by-one) so it overwrites first differing byte in first file's buffer. Attached patch fixes. Actual: $ cmp -b <(echo bad) <(echo bug) [snip] differ: byte 2, line 1 is 12 ^J 165 u Expected: $ cmp -b <(echo bad) <(echo bug) [snip] differ: byte 2, line 1 is 141 a 165 u Cheers! --mancha --aVD9QWMuhilNxW9f Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="cmp-newlines.patch" Content-Transfer-Encoding: quoted-printable --- a/src/cmp.c +++ b/src/cmp.c @@ -466,7 +466,7 @@ cmp (void) byte_number +=3D first_diff; if (comparison_type =3D=3D type_first_diff && first_diff !=3D 0) { - line_number +=3D count_newlines (buf0, first_diff); + line_number +=3D count_newlines (buf0, first_diff + 1); at_line_start =3D buf0[first_diff - 1] =3D=3D '\n'; } =20 --aVD9QWMuhilNxW9f-- --yVhtmJPUSI46BTXb Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJbVXo6AAoJEKPZDStQM/UXz0MQAIFKN4wueNRKH/Bs1A25E2BO b6aAG6beIUXvCJqd1LpDvfHNYeUdzx9pv/MFaoRSkk1WvTgv4BcUuJt7P4E3wOsc 53Bnw98JqAfPyFggBEW0uLjXUVdllnbl6WD6kVy+Zyd9DcnmgCuy/X1MGPQcl1+U JYoRItfCYjPFQPi4gdBTEA+2jqm4X/j0Azkdu6sZpAT28rcO8SQ5KgtJZrNgwwQY 7QkIgYp9+PynpJVgw3Oxe0RQ4fZC1VA+g7qVbH1rxQOZONETpJ7vBbfg7M3cVxp7 XMCQTgh3vn8uHSAOv7Ib/sWC047RxrEoxGAVE+h76v4ey+nM51GgaRRGd8fgbtES j6tdeElinMgTA+I2haghhp3Cq89wHOBmOPLP7pbmZJMqF1Rex9z+P8AIzj0ErNC8 JuNWl6U+lHg7txkjIhGtZJuhA2x1V3YmLlC/HGifbTX0xNyFxd4WG86Z5XYhj4WJ l53BM9ssb8H04KhetUQ5F1RRyCBXyVxFSdIWvdmbcGRS/iSLzTIVdfmWF+2qHEpQ fDfyCcIoLfIapETbe6UEyjur5GNZ8rcKqj8msR8D1UWh82uZUEAzYweYzSAVw+fs Y8Br05YUoLY2NZFjoJNgDC1mRz5SZlWduhbI2c0YbMYjo7NjSPLerc/srfH+4JDb LwY9LH9i1PKD9CYxjixy =amlv -----END PGP SIGNATURE----- --yVhtmJPUSI46BTXb-- ------------=_1532452862-13087-1--