From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa1-f71.google.com (mail-oa1-f71.google.com [209.85.160.71]) (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 8DE7921257F for ; Sat, 7 Mar 2026 01:21:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772846466; cv=none; b=JveBlZ3pB4BlzIOa9ugnuhwjOLB5MzMOob4FSCX7a4HDNCBxzufI6XqbkSpTvm4YOFkMRiRMwHKLav13+FTU6Oo9w8wj99vvEmQssLSTtxqvOl4w7Zo/sYAE4GUKWD6kDV+/2iWwALHoYQPSRNwaIdCMevaFNZOSg1Gtmy1ix5s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772846466; c=relaxed/simple; bh=qUA8YMvKzuZw5S39eL4fISnPgFkySO8bTa0btO77MhM=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=C9jmvXUpMdXVLekiS6Dnl/MPXUbRJSdlwHE9cnJvCn1E7DZJOTDzpENcgTOBl9gIJMDiQaAkbrP8hIKYvkwHeARkFJo8BrXvTvhQ7Jeoregg92C7iASgJVJBQP8b3I1DT+iBWPGfTyZZVcldBUpFtKs8O1aUkHxof9Dt9DFzNmU= 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=209.85.160.71 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-oa1-f71.google.com with SMTP id 586e51a60fabf-40450320b4fso21714154fac.0 for ; Fri, 06 Mar 2026 17:21:04 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772846463; x=1773451263; 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=3Q755ydJI/8rwjrXiRSLsXV0zUfT9ygGtfkaWo/B4Ag=; b=xME2im2tJdVsjT+qO0dDkZL7MJjnHk4QR8z9/Gqx3IRPKjeHYcByLxbpWCcq8g2prL VvdxnIi3/BlWiExKXt6JDCx1Nu/jyoeBjhGHPx628ANgNb0ZmhkG6QEbGgpwKOCpHX0O h6Q5+iNbwJXWEASpQjh1+ZoFtzCJ5KQPcYuphwDkBtgjft4DFJsheOa0u0SffsGelesy ZJfsUxn0bYEi1LakRLWpNHYmnF1MUznUmKgjYp6Z2DvwfBQo6mHHdayj4dO6mfAt/etS R/gA0pQoZ30v5jYFTvUaueKECwb3lOLWlewDJ/fm6D0akxq7+Fmwn4kEghGsy5TFLsj1 TbBg== X-Forwarded-Encrypted: i=1; AJvYcCX1CC0a4746vCtpkDhqL/rkV7NvfIZUdWqOfhiLuee7tou908c0kYWyWpeTvfGqKy7cE8C+1V4uX0byXoc=@vger.kernel.org X-Gm-Message-State: AOJu0YzCdHO0kPtFnsZ9Pdqx2+qmm+GZTcuq4Wc1Pm3P7pP0R828h9CP 1RZP5oPpSdNhHoLPx/1jpJPSQhxieMz3CA1FGelYWdAnQg95DzrCdRPDpc2IyfWNRFzTu37rU7q e9UhV0QskVk87Ob6FLd8lhJ6ElQfeh3VisKGc/WffctJVFrzNwo5MAUuDV5Y= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2297:b0:679:c549:203b with SMTP id 006d021491bc7-67b9bca5afcmr2597798eaf.25.1772846463548; Fri, 06 Mar 2026 17:21:03 -0800 (PST) Date: Fri, 06 Mar 2026 17:21:03 -0800 In-Reply-To: <20260307010633.41662-1-kartikey406@gmail.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69ab7d7f.050a0220.13f275.0037.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 qemu-system-x86_64: ahci: PRDT length for NCQ command (0x0) is smaller than= the requested size (0xec000) qemu-system-x86_64: ahci: PRDT length for NCQ command (0x0) is smaller than= the requested size (0x372000) qemu-system-x86_64: ahci: PRDT length for NCQ command (0x0) is smaller than= the requested size (0x2b4000) Warning: Permanently added '[localhost]:9553' (ED25519) to the list of know= n hosts. [ 60.013321][ T40] audit: type=3D1400 audit(1772846336.792:62): 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 [ 60.020535][ T40] audit: type=3D1400 audit(1772846336.802:63): 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 2026/03/07 01:18:58 parsed 1 programs [ 61.787218][ T40] audit: type=3D1400 audit(1772846338.562:64): avc: d= enied { node_bind } for pid=3D5928 comm=3D"syz-execprog" saddr=3D::1 scon= text=3Droot:sysadm_r:sysadm_t tcontext=3Dsystem_u:object_r:node_t tclass=3D= tcp_socket permissive=3D1 [ 64.314024][ T40] audit: type=3D1400 audit(1772846341.092:65): avc: d= enied { mounton } for pid=3D5937 comm=3D"syz-executor" path=3D"/syzcgroup= /unified" dev=3D"sda1" ino=3D2023 scontext=3Droot:sysadm_r:sysadm_t tcontex= t=3Droot:object_r:root_t tclass=3Ddir permissive=3D1 [ 64.325364][ T40] audit: type=3D1400 audit(1772846341.102:66): avc: d= enied { mount } for pid=3D5937 comm=3D"syz-executor" name=3D"/" dev=3D"cg= roup2" ino=3D1 scontext=3Droot:sysadm_r:sysadm_t tcontext=3Dsystem_u:object= _r:cgroup_t tclass=3Dfilesystem permissive=3D1 [ 64.327352][ T5937] cgroup: Unknown subsys name 'net' [ 64.338664][ T40] audit: type=3D1400 audit(1772846341.112:67): avc: d= enied { unmount } for pid=3D5937 comm=3D"syz-executor" scontext=3Droot:sy= sadm_r:sysadm_t tcontext=3Dsystem_u:object_r:cgroup_t tclass=3Dfilesystem p= ermissive=3D1 [ 64.492218][ T5937] cgroup: Unknown subsys name 'cpuset' [ 64.497527][ T5937] cgroup: Unknown subsys name 'rlimit' [ 64.697609][ T40] audit: type=3D1400 audit(1772846341.472:68): avc: d= enied { setattr } for pid=3D5937 comm=3D"syz-executor" name=3D"raw-gadget= " dev=3D"devtmpfs" ino=3D849 scontext=3Droot:sysadm_r:sysadm_t tcontext=3Ds= ystem_u:object_r:device_t tclass=3Dchr_file permissive=3D1 [ 64.709106][ T40] audit: type=3D1400 audit(1772846341.482:69): avc: d= enied { create } for pid=3D5937 comm=3D"syz-executor" scontext=3Droot:sys= adm_r:sysadm_t tcontext=3Droot:sysadm_r:sysadm_t tclass=3Dnetlink_generic_s= ocket permissive=3D1 [ 64.717475][ T40] audit: type=3D1400 audit(1772846341.482:70): avc: d= enied { write } for pid=3D5937 comm=3D"syz-executor" scontext=3Droot:sysa= dm_r:sysadm_t tcontext=3Droot:sysadm_r:sysadm_t tclass=3Dnetlink_generic_so= cket permissive=3D1 [ 64.726303][ T40] audit: type=3D1400 audit(1772846341.482:71): avc: d= enied { read } for pid=3D5937 comm=3D"syz-executor" scontext=3Droot:sysad= m_r:sysadm_t tcontext=3Droot:sysadm_r:sysadm_t tclass=3Dnetlink_generic_soc= ket permissive=3D1 [ 76.424366][ T1416] ieee802154 phy0 wpan0: encryption failed: -22 [ 76.427236][ T1416] ieee802154 phy1 wpan1: encryption failed: -22 [ 86.668293][ T29] cfg80211: failed to load regulatory.db [ 118.059383][ T1113] ata1.00: NCQ disabled due to excessive errors [ 118.062114][ T1113] ata1.00: exception Emask 0x0 SAct 0x40000120 SErr 0x= 0 action 0x6 frozen [ 118.065797][ T1113] ata1.00: failed command: WRITE FPDMA QUEUED [ 118.068375][ T1113] ata1.00: cmd 61/90:28:36:21:05/1b:00:00:00:00/40 tag= 5 ncq dma 3612672 ou [ 118.068375][ T1113] res 40/00:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x4 (timeout) [ 118.075829][ T1113] ata1.00: status: { DRDY } [ 118.077372][ T1113] ata1.00: failed command: WRITE FPDMA QUEUED [ 118.079529][ T1113] ata1.00: cmd 61/a0:40:36:61:05/15:00:00:00:00/40 tag= 8 ncq dma 2834432 ou [ 118.079529][ T1113] res 40/00:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x4 (timeout) [ 118.084906][ T1113] ata1.00: status: { DRDY } [ 118.086422][ T1113] ata1.00: failed command: WRITE FPDMA QUEUED [ 118.088377][ T1113] ata1.00: cmd 61/60:f0:76:4a:04/07:00:00:00:00/40 tag= 30 ncq dma 966656 out [ 118.088377][ T1113] res 40/00:00:00:00:00/00:00:00:00:00/00 Ema= sk 0x4 (timeout) [ 118.093826][ T1113] ata1.00: status: { DRDY } [ 118.095370][ T1113] ata1: hard resetting link [ 118.414125][ T1113] ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 30= 0) [ 118.417532][ T1113] ata1.00: configured for UDMA/100 [ 118.419565][ T1113] 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-build632602998=3D/tmp/go-build -gno-record-gcc= -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/ccWzPJKl.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=3D12486b5a5800= 00