From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f71.google.com (mail-io1-f71.google.com [209.85.166.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 021F464D for ; Thu, 9 May 2024 00:22:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715214159; cv=none; b=TYJ8N5wsqVvSis5kCOWbBrTTG+r1Bn4uqSi1t7z2tMo7QTb3rvA82gj6q4eLpULXCHcN/uFtlUOWkDy+HutaMU+qewHeqYS5BqFlRp3Kj7GSEXtlWoEa+LFNlq9UxVuDzKZ0m1rAhNfp3gxnDsoAEGn4p+8Q+rJ9PUgKqWghVf8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715214159; c=relaxed/simple; bh=l9xvlp8mrxeR8KRimpw6XquSnAWFPAab02KC7tmXc3Q=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=tEqFfPxy6DupENX90lFdvXPsvYHDzsi3W/lDOyPxYz4A9Yztyu4w0rFcJd7qKzPK4rN53GjxNJwmyCC8yCw7pIHCirzJlnQed/ZL0y4aeeUgaxTXRmfjcJpilbam9MsVuZNj6/Ipqr324D9qqGKKICjJKKE1lPP9b4o65kkKzZw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.71 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f71.google.com with SMTP id ca18e2360f4ac-7e17a8bed9eso22686339f.0 for ; Wed, 08 May 2024 17:22:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1715214157; x=1715818957; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=lfqIbh/n8c/JvAZGLAr1nhft2YgtPBcREnLCX/t7Ouo=; b=ZRFRhdxFXt/vVMR1PcOZfNePAfcPxKd/GRC5I2gs16MOLxtAdc8j8TvEY0ROwQ2vdm BiXZhW/bM5+wtVFnOGI97d8qWFXSabJigzHbg5TOmrwKWF0AnNW6zMZ6npHEBZJTWmEV llR9V+LaUVtVgbHpaVf15zQ5/9R9Avzq0PKxl3234LOsGOTKS6Ehdt8BIf6NKaDYfDGk 3+o9P3z7i989K8nDu//BhOp0BCso2VxUIXp0zb60mw4WUh4h98tn9L4248H7+YITt54D pbVJTNmU/hNIlpWMesb5LThbcYexJEBTVc5lDfjchFEBX6A+YoiwakQDPSXvAIL58ycw SoCQ== X-Gm-Message-State: AOJu0Ywl5nuFJNiRPgKPZzoXdf1OYcCyhLBAGqD6KJloiiHj4xjQysAw KyUERfa7Ye6pXZDD57qvqoZa+IS4asqadRtblbyaP4miW45renP8MhMtmhBRGHrwm4OVsr23KjC IcOayEsHlr/1zUKTIdIULyfQgwDs/Lc+lB90/3D0fHoBLIBSLaExyLcs= X-Google-Smtp-Source: AGHT+IEjOZsQuVPeyFb1IvYgsEtOl50gaaoZq+ZmQEmfxzJLjQ8LNDZpDDzcNCkoUCbYlO5AO+IQ3aghEUTtiaVPz0+jXYklTD1H Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6638:144e:b0:488:5ceb:9533 with SMTP id 8926c6da1cb9f-488fd355a5fmr257833173.0.1715214157190; Wed, 08 May 2024 17:22:37 -0700 (PDT) Date: Wed, 08 May 2024 17:22:37 -0700 In-Reply-To: <0000000000006a59f00617ecd989@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000008daaac0617fa6a18@google.com> Subject: Re: [syzbot] [PATCH] bcachefs: guard against invalid bits_per_field in bch2_bkey_format_invalid From: syzbot To: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org. *** Subject: [PATCH] bcachefs: guard against invalid bits_per_field in bch2_bkey_format_invalid Author: cam.alvarez.i@gmail.com #syz test git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master A check for a valid value for bits_per_field is performed for each field before computing packed_max. If bits_per_field is invalid for any field the whole format is deemed invalid. Signed-off-by: Camila Alvarez --- fs/bcachefs/bcachefs_format.h | 8 ++++++++ fs/bcachefs/bkey.c | 17 +++++++++++++++-- 2 files changed, 23 insertions(+), 2 deletions(-) diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h index d5b90439e581..23eb04148724 100644 --- a/fs/bcachefs/bcachefs_format.h +++ b/fs/bcachefs/bcachefs_format.h @@ -318,6 +318,14 @@ enum bch_bkey_fields { #define bkey_format_field(name, field) \ [BKEY_FIELD_##name] = (sizeof(((struct bkey *) NULL)->field) * 8) +#define BCH_BKEY_FIELDS() \ + x(INODE, p.inode) \ + x(OFFSET, p.offset) \ + x(SNAPSHOT, p.snapshot) \ + x(SIZE, size) \ + x(VERSION_HI, version.hi) \ + x(VERSION_LO, version.lo) + #define BKEY_FORMAT_CURRENT \ ((struct bkey_format) { \ .key_u64s = BKEY_U64s, \ diff --git a/fs/bcachefs/bkey.c b/fs/bcachefs/bkey.c index 76e79a15ba08..b6004b5f77e0 100644 --- a/fs/bcachefs/bkey.c +++ b/fs/bcachefs/bkey.c @@ -638,6 +638,13 @@ struct bkey_format bch2_bkey_format_done(struct bkey_format_state *s) return ret; } +static unsigned bch2_max_bits_per_field[] = { +#define x(name, field) \ + bkey_format_field(name, field), + BCH_BKEY_FIELDS() +#undef x +}; + int bch2_bkey_format_invalid(struct bch_fs *c, struct bkey_format *f, enum bkey_invalid_flags flags, @@ -659,8 +666,14 @@ int bch2_bkey_format_invalid(struct bch_fs *c, if (!c || c->sb.version_min >= bcachefs_metadata_version_snapshot) { unsigned unpacked_bits = bch2_bkey_format_current.bits_per_field[i]; u64 unpacked_max = ~((~0ULL << 1) << (unpacked_bits - 1)); - u64 packed_max = f->bits_per_field[i] - ? ~((~0ULL << 1) << (f->bits_per_field[i] - 1)) + unsigned bits_per_field = f->bits_per_field[i]; + if (bits_per_field > bch2_max_bits_per_field[i]) { + prt_printf(err, "field %u uses more bits than allowed: %u > %u", + i, bits_per_field, bch2_max_bits_per_field[i]); + return -BCH_ERR_invalid; + } + u64 packed_max = bits_per_field + ? ~((~0ULL << 1) << (bits_per_field - 1)) : 0; u64 field_offset = le64_to_cpu(f->field_offset[i]); -- 2.34.1