From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f70.google.com (mail-oo1-f70.google.com [209.85.161.70]) (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 EAD6A18DF9D for ; Sat, 7 Mar 2026 00:40:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772844004; cv=none; b=sOqL79/jb7QpxrAoG3NlOOUoRr7VKqn+SZevu4siJXM3JIA+r7qsBP6KYi7bBkcxtSVSoE67E48XuKSmIMv/Kn8fnhaXJQJ1Zx53is+zPoTwK2ABeLwxdwb5TPicQSmbUy/ZBlDNjmzMPJw2rzihxGzFg9/94tY/pncVtGNPquo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772844004; c=relaxed/simple; bh=OSwjMa2xnQtCQM9Cn2g1272BcoYXZjQuTKr1ebaSfZU=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=Jsa7gILuIZlfuIb2/kZGed3m85FfoCD9xYvADfPwfjnjKRkHq+Xl2RhGKQALESfgoeHea/HTnJ4kl2ajz/enLx7cA0FmUMg3Eg1d8a10n9Myz9fXiWMfiIn416zpIUpMO76PDzu3l9XwNir83ct7kG/p7dc41jmINfnS7+5dQQk= 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=209.85.161.70 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-oo1-f70.google.com with SMTP id 006d021491bc7-679dda090fbso160028861eaf.2 for ; Fri, 06 Mar 2026 16:40:02 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772844002; x=1773448802; h=content-transfer-encoding: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=pfbFzONuKsJDSDUoD52MNlI+C+Z/dtstpoBA16o9d9g=; b=jVrMEqnXm/WAaf+uAtrT1R8gaeLzXCAkbgEutFs9kv8CrC/53J7IfkBJkpw53WCXhX 6C7PyQi1z/Uio8GfGxIx7tvt7ZeMh+TWPZ878hZIYo1K0j1Yqt2Lqk1jCLsAyewLft5R LpRxY1W8REypUyGwtYpPPdyNZVJmyjdT7G2AS00HediYthO/RRzrpY9kOY0DB6NJ583P tEjiDBhuZwHJLIP4Y0v8LUkLHnz3CFBmPe4RzDUn/ela70U9Hm6KHMbQ+6hrahFGFbTe nBHsfWktbHzemiIlv8RpRHIVthR89UwMxubHy2EUBjsyvRLIXydmEkukyP9nSTN9sQeU BkyA== X-Forwarded-Encrypted: i=1; AJvYcCWVXnjmJ5H5JqPI04AoSe69a4Km2oPnNAks1BSA4yNx3q37ilPcXld1vVqB+tUd1daTSamm85w4XJYc/w0=@vger.kernel.org X-Gm-Message-State: AOJu0YwPikF6EwMv9oN5Q2U4rRP4ck02Dytedns/8LGj9Zk49uorAvCp MaNt6uIIO3x3hwNVz8XRtJiZd8xRQAKUu41LNvWShSvRrXa8bXqH2gaEIbC9j2C3pc2eV7H2br7 BoqxZRo+U6ydO6z68KrkdxYJ1ju9TOwtdb8z+sB6cRvUsZusMJ16+1Lr+V4E= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:f07:b0:679:976a:98bc with SMTP id 006d021491bc7-67b9bd0d7c8mr2558938eaf.36.1772844001957; Fri, 06 Mar 2026 16:40:01 -0800 (PST) Date: Fri, 06 Mar 2026 16:40:01 -0800 In-Reply-To: <20260307001235.30412-1-kartikey406@gmail.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69ab73e1.050a0220.13f275.0032.GAE@google.com> Subject: Re: [syzbot] [netfs?] BUG: unable to handle kernel NULL pointer dereference in netfs_unbuffered_write From: syzbot To: kartikey406@gmail.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hello, syzbot tried to test the proposed patch but the build/boot failed: lost connection to test machine [ 52.755134][ T40] audit: type=3D1400 audit(1772843937.457:60): avc: d= enied { rlimitinh } for pid=3D5908 comm=3D"sh" scontext=3Dsystem_u:system= _r:sshd_t tcontext=3Droot:sysadm_r:sysadm_t tclass=3Dprocess permissive=3D1 [ 52.762936][ T40] audit: type=3D1400 audit(1772843937.457:61): avc: d= enied { siginh } for pid=3D5908 comm=3D"sh" scontext=3Dsystem_u:system_r:= sshd_t tcontext=3Droot:sysadm_r:sysadm_t tclass=3Dprocess permissive=3D1 Warning: Permanently added '[localhost]:9893' (ED25519) to the list of know= n hosts. [ 59.078731][ T40] audit: type=3D1400 audit(1772843943.797:62): avc: d= enied { execute } for pid=3D5928 comm=3D"sh" name=3D"syz-execprog" dev=3D= "sda1" ino=3D2020 scontext=3Droot:sysadm_r:sysadm_t tcontext=3Droot:object_= r:etc_runtime_t tclass=3Dfile permissive=3D1 [ 59.085870][ T40] audit: type=3D1400 audit(1772843943.797:63): avc: d= enied { execute_no_trans } for pid=3D5928 comm=3D"sh" path=3D"/syz-execpr= og" dev=3D"sda1" ino=3D2020 scontext=3Droot:sysadm_r:sysadm_t tcontext=3Dro= ot:object_r:etc_runtime_t tclass=3Dfile permissive=3D1 qemu-system-x86_64: ahci: PRDT length for NCQ command (0x0) is smaller than= the requested size (0x99000) [ 59.742863][ T1116] ata1.00: Read log 0x10 page 0x00 failed, Emask 0x1 [ 59.745980][ T1116] ata1: failed to read log page 10h (errno=3D-5) [ 59.748698][ T1116] ata1.00: exception Emask 0x1 SAct 0x40000001 SErr 0x= 0 action 0x0 [ 59.752402][ T1116] ata1.00: irq_stat 0x41000000 [ 59.754519][ T1116] ata1.00: failed command: WRITE FPDMA QUEUED [ 59.757324][ T1116] ata1.00: cmd 61/58:00:d6:6d:04/06:00:00:00:00/40 tag= 0 ncq dma 831488 out [ 59.757324][ T1116] res 50/00:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x1 (device error) [ 59.764851][ T1116] ata1.00: status: { DRDY } [ 59.766900][ T1116] ata1.00: failed command: WRITE FPDMA QUEUED [ 59.769743][ T1116] ata1.00: cmd 61/c8:f0:0e:69:04/04:00:00:00:00/40 tag= 30 ncq dma 626688 out [ 59.769743][ T1116] res 50/00:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x1 (device error) [ 59.777328][ T1116] ata1.00: status: { DRDY } [ 59.780442][ T1116] ata1.00: configured for UDMA/100 [ 59.783246][ T1116] ata1: EH complete qemu-system-x86_64: ahci: PRDT length for NCQ command (0x0) is smaller than= the requested size (0x400000) qemu-system-x86_64: ahci: PRDT length for NCQ command (0x0) is smaller than= the requested size (0x400000) [ 60.002677][ T1116] ata1.00: Read log 0x10 page 0x00 failed, Emask 0x1 [ 60.005615][ T1116] ata1: failed to read log page 10h (errno=3D-5) [ 60.008370][ T1116] ata1.00: NCQ disabled due to excessive errors [ 60.011117][ T1116] ata1.00: exception Emask 0x1 SAct 0x89000000 SErr 0x= 0 action 0x0 [ 60.014746][ T1116] ata1.00: irq_stat 0x41000000 [ 60.016900][ T1116] ata1.00: failed command: WRITE FPDMA QUEUED [ 60.019566][ T1116] ata1.00: cmd 61/00:c0:f6:06:05/20:00:00:00:00/40 tag= 24 ncq dma 4194304 ou [ 60.019566][ T1116] res 50/04:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x1 (device error) [ 60.027211][ T1116] ata1.00: status: { DRDY } [ 60.029244][ T1116] ata1.00: error: { ABRT } [ 60.031278][ T1116] ata1.00: failed command: WRITE FPDMA QUEUED [ 60.034084][ T1116] ata1.00: cmd 61/00:d8:36:61:05/20:00:00:00:00/40 tag= 27 ncq dma 4194304 ou [ 60.034084][ T1116] res 50/04:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x1 (device error) [ 60.041564][ T1116] ata1.00: status: { DRDY } [ 60.043728][ T1116] ata1.00: error: { ABRT } [ 60.045740][ T1116] ata1.00: failed command: WRITE FPDMA QUEUED [ 60.048454][ T1116] ata1.00: cmd 61/38:f8:36:81:05/0d:00:00:00:00/40 tag= 31 ncq dma 1732608 ou [ 60.048454][ T1116] res 50/04:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x1 (device error) [ 60.056127][ T1116] ata1.00: status: { DRDY } [ 60.058176][ T1116] ata1.00: error: { ABRT } [ 60.061129][ T1116] ata1.00: configured for UDMA/100 [ 60.064028][ T1116] ata1: EH complete qemu-system-x86_64: hw/ide/core.c:934: ide_dma_cb: Assertion `prep_size >= =3D 0 && prep_size <=3D n * 512' failed. Connection to localhost closed by remote host. syzkaller build log: go env (err=3D) AR=3D'ar' CC=3D'gcc' CGO_CFLAGS=3D'-O2 -g' CGO_CPPFLAGS=3D'' CGO_CXXFLAGS=3D'-O2 -g' CGO_ENABLED=3D'1' CGO_FFLAGS=3D'-O2 -g' CGO_LDFLAGS=3D'-O2 -g' CXX=3D'g++' GCCGO=3D'gccgo' GO111MODULE=3D'auto' GOAMD64=3D'v1' GOARCH=3D'amd64' GOAUTH=3D'netrc' GOBIN=3D'' GOCACHE=3D'/syzkaller/.cache/go-build' GOCACHEPROG=3D'' GODEBUG=3D'' GOENV=3D'/syzkaller/.config/go/env' GOEXE=3D'' GOEXPERIMENT=3D'' GOFIPS140=3D'off' GOFLAGS=3D'' GOGCCFLAGS=3D'-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=3D0= -ffile-prefix-map=3D/tmp/go-build1140076034=3D/tmp/go-build -gno-record-gc= c-switches' GOHOSTARCH=3D'amd64' GOHOSTOS=3D'linux' GOINSECURE=3D'' GOMOD=3D'/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mo= d' GOMODCACHE=3D'/syzkaller/jobs/linux/gopath/pkg/mod' GONOPROXY=3D'' GONOSUMDB=3D'' GOOS=3D'linux' GOPATH=3D'/syzkaller/jobs/linux/gopath' GOPRIVATE=3D'' GOPROXY=3D'https://proxy.golang.org,direct' GOROOT=3D'/usr/local/go' GOSUMDB=3D'sum.golang.org' GOTELEMETRY=3D'local' GOTELEMETRYDIR=3D'/syzkaller/.config/go/telemetry' GOTMPDIR=3D'' GOTOOLCHAIN=3D'auto' GOTOOLDIR=3D'/usr/local/go/pkg/tool/linux_amd64' GOVCS=3D'' GOVERSION=3D'go1.24.4' GOWORK=3D'' PKG_CONFIG=3D'pkg-config' git status (err=3D) HEAD detached at d20b04c80a0 nothing to commit, working tree clean tput: No value for $TERM and no -T specified tput: No value for $TERM and no -T specified Makefile:31: run command via tools/syz-env for best compatibility, see: Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contribut= ing.md#using-syz-env go list -f '{{.Stale}}' -ldflags=3D"-s -w -X github.com/google/syzkaller/pr= og.GitRevision=3Dd20b04c80a01e68026299511a6ba77cc67a198f5 -X github.com/goo= gle/syzkaller/prog.gitRevisionDate=3D20260305-101922" ./sys/syz-sysgen | g= rep -q false || go install -ldflags=3D"-s -w -X github.com/google/syzkaller= /prog.GitRevision=3Dd20b04c80a01e68026299511a6ba77cc67a198f5 -X github.com/= google/syzkaller/prog.gitRevisionDate=3D20260305-101922" ./sys/syz-sysgen make .descriptions tput: No value for $TERM and no -T specified tput: No value for $TERM and no -T specified Makefile:31: run command via tools/syz-env for best compatibility, see: Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contribut= ing.md#using-syz-env bin/syz-sysgen touch .descriptions GOOS=3Dlinux GOARCH=3Damd64 go build -ldflags=3D"-s -w -X github.com/google= /syzkaller/prog.GitRevision=3Dd20b04c80a01e68026299511a6ba77cc67a198f5 -X g= ithub.com/google/syzkaller/prog.gitRevisionDate=3D20260305-101922" -o ./bi= n/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog mkdir -p ./bin/linux_amd64 g++ -o ./bin/linux_amd64/syz-executor executor/executor.cc \ -m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wfr= ame-larger-than=3D16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-forma= t-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -= static-pie -std=3Dc++17 -I. -Iexecutor/_include -DGOOS_linux=3D1 -DGOARCH= _amd64=3D1 \ -DHOSTGOOS_linux=3D1 -DGIT_REVISION=3D\"d20b04c80a01e68026299511a6ba77cc67= a198f5\" /usr/bin/ld: /tmp/ccLEWSPc.o: in function `Connection::Connect(char const*,= char const*)': executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEP= KcS1_]+0x386): warning: Using 'gethostbyname' in statically linked applicat= ions requires at runtime the shared libraries from the glibc version used f= or linking ./tools/check-syzos.sh 2>/dev/null Tested on: commit: 325a118c Merge tag 'pci-v7.0-fixes-3' of git://git.ker.. git tree: upstream kernel config: https://syzkaller.appspot.com/x/.config?x=3D976ba5a93c4add9= e dashboard link: https://syzkaller.appspot.com/bug?extid=3D7227db0fbac9f348d= ba0 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Deb= ian) 2.44 patch: https://syzkaller.appspot.com/x/patch.diff?x=3D1223d5525800= 00