From nobody Wed May 10 15:02:25 2023 X-Original-To: bugs@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4QGdYG0tFZz4B1Gf for ; Wed, 10 May 2023 15:02:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4QGdYF569xz3wJ9 for ; Wed, 10 May 2023 15:02:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1683730945; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=zJiGZuFyM3j9dYX7fl43FRU5oFqefSg2UDvrCF65RQM=; b=VICysUxXD6b8iS4TC3GYcZLCmhTvLvkm9LWKqGG7a1RSUo45S8qzdksqCluv3HkNIAer/W yPerX3izFZ1vBAe9HbpWKgViQau0z9kKXA28yN9DpWtH1txFWfEd/fc6gd5cBRkPKimndd OoZ9VlRjcMhpH/GgT+hbGHYw1ska4uESfVBShEKHt68QDI++pOz/Ge+T+VODJBqN4/H1pb YK4/xoNXz4SigZRDq2f8I+zNF0BexGh6NQUOQjfWTikKPBeEtSu2X2Mrc9JOo8crfiov1H 9vDU6t4a/aoqlHTkS/H2X2s3ledos4xiiLPihd4UIqE2ZHPwZNlUimfj0/A4MA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1683730945; a=rsa-sha256; cv=none; b=q+yRRI8FKxuXQC77PuREt/CdBz/bP0G+ZsZVteX7fr0q2KyyHI47bxHDnlQKxhXL+tItaE 9Sai0ChLtRfWOIKo8oEaHhi95JGgZUc5G03frWWCRGC7NDZhziVLHiB1VEbHS4ukBPgJ7z ZES38X+IMpQEA/MXIERx88iFPh0fhZ6CHksH4aQBAs/QkdObF8EYCPwG2Ampr4/7KXo9hS vBvms/645/8aLYLVsvIvpFPipDcLzlGKpj3ZWn3mzzSB6/ndB/PCF5NSr0AZ08+Pp6l1b/ Jsf74MEGdJWEldeq5QnXDmOiE3L65crsEyVMfiiwd8kMUheWkV4g8ZbRj3iUvQ== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4QGdYF4B0HzFZg for ; Wed, 10 May 2023 15:02:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 34AF2PeL001305 for ; Wed, 10 May 2023 15:02:25 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 34AF2Pnw001304 for bugs@FreeBSD.org; Wed, 10 May 2023 15:02:25 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 271351] fsck_ffs can crash if fs_size < fs_ncg*fs_fpg Date: Wed, 10 May 2023 15:02:25 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: rtm@lcs.mit.edu X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Bug reports List-Archive: https://lists.freebsd.org/archives/freebsd-bugs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-bugs@freebsd.org MIME-Version: 1.0 X-ThisMailContainsUnwantedMimeParts: N https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D271351 Bug ID: 271351 Summary: fsck_ffs can crash if fs_size < fs_ncg*fs_fpg Product: Base System Version: CURRENT Hardware: Any OS: Any Status: New Severity: Affects Some People Priority: --- Component: bin Assignee: bugs@FreeBSD.org Reporter: rtm@lcs.mit.edu Created attachment 242107 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=3D242107&action= =3Dedit broken image that causes fsck_ffs to crash due to fs_size < fs_ncg*fs_fpg These two checks in ffs_subr.c's validate_sblock(): FCHK(fs->fs_size, <=3D, ((int64_t)fs->fs_ncg - 1) * fs->fs_= fpg, %jd); and=20 FCHK(fs->fs_size, <=3D, ((int64_t)fs->fs_ncg - 1) * fs->fs_fpg, %jd= ); allow fs_size to be smaller than fs_ncg*fs_fpg. For example, if fs_ncg is 1, then the test only requires fs_size to be > 0. validate_sblock() checks fs_csaddr against fs_ncg*fs_fpg, and thus fs_csaddr can point beyond fs_size. As a result, a too-large value of fs_csaddr can cause this code in fsck_ffs's pass1() to write beyond the end of blockmap, whose size is determined by fs_size: i =3D sblock.fs_csaddr; cgd =3D i + howmany(sblock.fs_cssize, sblock.fs_fsize); for (; i < cgd; i++) setbmap(i); I've attached a file system image that causes fsck_ffs -y to either dump core or fail valgrind. --=20 You are receiving this mail because: You are the assignee for the bug.=