Re: [syzbot] [erofs?] KMSAN: uninit-value in z_erofs_lz4_decompress (3)

From: Gao Xiang
Date: Tue Feb 20 2024 - 02:48:24 EST


(+add -netdev)

On 2024/2/20 15:22, syzbot wrote:
Hello,

syzbot tried to test the proposed patch but the build/boot failed:

le Layout Driver Registering...

..

[ 29.540501][ T1] null_blk: disk nullb0 created
[ 29.545733][ T1] null_blk: module loaded
[ 29.551941][ T1] Guest personality initialized and is inactive
[ 29.560955][ T1] VMCI host device registered (name=vmci, major=10, minor=118)
[ 29.569840][ T1] Initialized host personality
[ 29.575750][ T1] usbcore: registered new interface driver rtsx_usb
[ 29.585633][ T1] usbcore: registered new interface driver viperboard
[ 29.594432][ T1] usbcore: registered new interface driver dln2
[ 29.602202][ T1] usbcore: registered new interface driver pn533_usb
[ 29.616932][ T1] nfcsim 0.2 initialized
[ 29.622086][ T1] usbcore: registered new interface driver port100
[ 29.629914][ T1] usbcore: registered new interface driver nfcmrvl
[ 29.648231][ T1] Loading iSCSI transport class v2.0-870.
[ 29.684669][ T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
[ 29.731303][ T1] scsi host0: Virtio SCSI HBA
[ 30.283396][ T1] st: Version 20160209, fixed bufsize 32768, s/g segs 256
[ 30.301725][ T72] scsi 0:0:1:0: Direct-Access Google PersistentDisk 1 PQ: 0 ANSI: 6
[ 30.344813][ T1] Rounding down aligned max_sectors from 4294967295 to 4294967288
[ 30.362347][ T1] db_root: cannot open: /etc/target
[ 30.395006][ T1] =====================================================
[ 30.395260][ T1] BUG: KMSAN: use-after-free in __list_del_entry_valid_or_report+0x19e/0x490
[ 30.395432][ T1] __list_del_entry_valid_or_report+0x19e/0x490
[ 30.395596][ T1] stack_depot_save_flags+0x3e7/0x7b0
[ 30.395700][ T1] stack_depot_save+0x12/0x20
[ 30.395793][ T1] ref_tracker_alloc+0x215/0x700
[ 30.395890][ T1] netdev_queue_update_kobjects+0x256/0x870
[ 30.396031][ T1] netdev_register_kobject+0x41e/0x520

It seems it got some similar boot-failure issue:
https://lore.kernel.org/r/00000000000036e27e0610890a65@xxxxxxxxxx
https://lore.kernel.org/r/000000000000bacd1706107232cd@xxxxxxxxxx

before I tend to verify a resolved duplicated report:
https://syzkaller.appspot.com/bug?extid=6c746eea496f34b3161d

Thanks,
Gao Xiang

[ 30.396149][ T1] register_netdevice+0x198f/0x2170
[ 30.396264][ T1] bond_create+0x138/0x2a0
[ 30.396406][ T1] bonding_init+0x1a7/0x2d0
[ 30.396505][ T1] do_one_initcall+0x216/0x960
[ 30.396640][ T1] do_initcall_level+0x140/0x350
[ 30.396748][ T1] do_initcalls+0xf0/0x1d0
[ 30.396848][ T1] do_basic_setup+0x22/0x30
[ 30.396959][ T1] kernel_init_freeable+0x300/0x4b0
[ 30.397071][ T1] kernel_init+0x2f/0x7e0
[ 30.397189][ T1] ret_from_fork+0x66/0x80
[ 30.397216][ T1] ret_from_fork_asm+0x11/0x20
[ 30.397216][ T1]
[ 30.397216][ T1] Uninit was created at:
[ 30.397216][ T1] free_unref_page_prepare+0xc1/0xad0
[ 30.397216][ T1] free_unref_page+0x58/0x6d0
[ 30.397216][ T1] __free_pages+0xb1/0x1f0
[ 30.397216][ T1] thread_stack_free_rcu+0x97/0xb0
[ 30.397216][ T1] rcu_core+0xa3c/0x1df0
[ 30.397216][ T1] rcu_core_si+0x12/0x20
[ 30.397216][ T1] __do_softirq+0x1b7/0x7c3
[ 30.397216][ T1]
[ 30.397216][ T1] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.8.0-rc5-syzkaller-gb401b621758e #0
[ 30.397216][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
[ 30.397216][ T1] =====================================================
[ 30.397216][ T1] Disabling lock debugging due to kernel taint
[ 30.397216][ T1] Kernel panic - not syncing: kmsan.panic set ...
[ 30.397216][ T1] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G B 6.8.0-rc5-syzkaller-gb401b621758e #0
[ 30.397216][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
[ 30.397216][ T1] Call Trace:
[ 30.397216][ T1] <TASK>
[ 30.397216][ T1] dump_stack_lvl+0x1bf/0x240
[ 30.397216][ T1] dump_stack+0x1e/0x20
[ 30.397216][ T1] panic+0x4de/0xc90
[ 30.397216][ T1] kmsan_report+0x2d0/0x2d0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? __msan_warning+0x96/0x110
[ 30.397216][ T1] ? __list_del_entry_valid_or_report+0x19e/0x490
[ 30.397216][ T1] ? stack_depot_save_flags+0x3e7/0x7b0
[ 30.397216][ T1] ? stack_depot_save+0x12/0x20
[ 30.397216][ T1] ? ref_tracker_alloc+0x215/0x700
[ 30.397216][ T1] ? netdev_queue_update_kobjects+0x256/0x870
[ 30.397216][ T1] ? netdev_register_kobject+0x41e/0x520
[ 30.397216][ T1] ? register_netdevice+0x198f/0x2170
[ 30.397216][ T1] ? bond_create+0x138/0x2a0
[ 30.397216][ T1] ? bonding_init+0x1a7/0x2d0
[ 30.397216][ T1] ? do_one_initcall+0x216/0x960
[ 30.397216][ T1] ? do_initcall_level+0x140/0x350
[ 30.397216][ T1] ? do_initcalls+0xf0/0x1d0
[ 30.397216][ T1] ? do_basic_setup+0x22/0x30
[ 30.397216][ T1] ? kernel_init_freeable+0x300/0x4b0
[ 30.397216][ T1] ? kernel_init+0x2f/0x7e0
[ 30.397216][ T1] ? ret_from_fork+0x66/0x80
[ 30.397216][ T1] ? ret_from_fork_asm+0x11/0x20
[ 30.397216][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.397216][ T1] ? _raw_spin_lock_irqsave+0x35/0xc0
[ 30.397216][ T1] ? filter_irq_stacks+0x60/0x1a0
[ 30.397216][ T1] ? stack_depot_save_flags+0x2c/0x7b0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.397216][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.397216][ T1] __msan_warning+0x96/0x110
[ 30.397216][ T1] __list_del_entry_valid_or_report+0x19e/0x490
[ 30.397216][ T1] stack_depot_save_flags+0x3e7/0x7b0
[ 30.397216][ T1] stack_depot_save+0x12/0x20
[ 30.397216][ T1] ref_tracker_alloc+0x215/0x700
[ 30.397216][ T1] ? netdev_queue_update_kobjects+0x256/0x870
[ 30.397216][ T1] ? netdev_register_kobject+0x41e/0x520
[ 30.397216][ T1] ? register_netdevice+0x198f/0x2170
[ 30.397216][ T1] ? bond_create+0x138/0x2a0
[ 30.397216][ T1] ? bonding_init+0x1a7/0x2d0
[ 30.397216][ T1] ? do_one_initcall+0x216/0x960
[ 30.397216][ T1] ? do_initcall_level+0x140/0x350
[ 30.397216][ T1] ? do_initcalls+0xf0/0x1d0
[ 30.397216][ T1] ? do_basic_setup+0x22/0x30
[ 30.397216][ T1] ? kernel_init_freeable+0x300/0x4b0
[ 30.397216][ T1] ? kernel_init+0x2f/0x7e0
[ 30.397216][ T1] ? ret_from_fork+0x66/0x80
[ 30.397216][ T1] ? ret_from_fork_asm+0x11/0x20
[ 30.397216][ T1] ? kmsan_internal_unpoison_memory+0x14/0x20
[ 30.397216][ T1] netdev_queue_update_kobjects+0x256/0x870
[ 30.397216][ T1] netdev_register_kobject+0x41e/0x520
[ 30.397216][ T1] register_netdevice+0x198f/0x2170
[ 30.397216][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.397216][ T1] bond_create+0x138/0x2a0
[ 30.397216][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.397216][ T1] bonding_init+0x1a7/0x2d0
[ 30.397216][ T1] ? spi_dln2_driver_init+0x40/0x40
[ 30.397216][ T1] do_one_initcall+0x216/0x960
[ 30.397216][ T1] ? spi_dln2_driver_init+0x40/0x40
[ 30.397216][ T1] ? kmsan_get_metadata+0xb0/0x1c0
[ 30.397216][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.397216][ T1] ? filter_irq_stacks+0x60/0x1a0
[ 30.397216][ T1] ? stack_depot_save_flags+0x2c/0x7b0
[ 30.407722][ T1] ? skip_spaces+0x8f/0xc0
[ 30.407722][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.407922][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.407922][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.407922][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.407922][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.407922][ T1] ? parse_args+0x1511/0x15e0
[ 30.407922][ T1] ? kmsan_get_metadata+0x146/0x1c0
[ 30.407922][ T1] ? kmsan_get_shadow_origin_ptr+0x4d/0xa0
[ 30.407922][ T1] ? spi_dln2_driver_init+0x40/0x40
[ 30.408958][ T1] do_initcall_level+0x140/0x350
[ 30.408958][ T1] do_initcalls+0xf0/0x1d0
[ 30.408958][ T1] ? arch_cpuhp_init_parallel_bringup+0xe0/0xe0
[ 30.408958][ T1] do_basic_setup+0x22/0x30
[ 30.408958][ T1] kernel_init_freeable+0x300/0x4b0
[ 30.408958][ T1] ? rest_init+0x260/0x260
[ 30.408958][ T1] kernel_init+0x2f/0x7e0
[ 30.408958][ T1] ? rest_init+0x260/0x260
[ 30.408958][ T1] ret_from_fork+0x66/0x80
[ 30.409978][ T1] ? rest_init+0x260/0x260
[ 30.409978][ T1] ret_from_fork_asm+0x11/0x20
[ 30.409978][ T1] </TASK>
[ 30.409978][ T1] Kernel Offset: disabled


syzkaller build log:
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/syzkaller/jobs-2/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs-2/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.21.4'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build1804868575=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 373b66cd2
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:32: run command via tools/syz-env for best compatibility, see:
Makefile:33: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=373b66cd2ba1fd05c72d0bbe16141fb287fe2eb3 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240130-131205'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-fuzzer github.com/google/syzkaller/syz-fuzzer
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=373b66cd2ba1fd05c72d0bbe16141fb287fe2eb3 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240130-131205'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=373b66cd2ba1fd05c72d0bbe16141fb287fe2eb3 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240130-131205'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-stress github.com/google/syzkaller/tools/syz-stress
mkdir -p ./bin/linux_amd64
gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \
-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \
-DHOSTGOOS_linux=1 -DGIT_REVISION=\"373b66cd2ba1fd05c72d0bbe16141fb287fe2eb3\"


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=12579b34180000


Tested on:

commit: b401b621 Linux 6.8-rc5
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=d33318d4e4a0d226
dashboard link: https://syzkaller.appspot.com/bug?extid=88ad8b0517a9d3bb9dc8
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.