Re: [syzbot] [hfs?] KMSAN: uninit-value in hfs_revalidate_dentry

[syzbot <syzbot+3ae6be33a50b5aae4dab@syzkaller.appspotmail.com>]

Hello,

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

  T1] ALSA device list:
[   49.732806][    T1]   #0: Dummy 1
[   49.736413][    T1]   #1: Loopback 1
[   49.740228][    T1]   #2: Virtual MIDI Card 1
[   49.750262][   T10] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
[   49.760115][   T10] platform regulatory.0: Falling back to sysfs fallback for: regulatory.db
[   49.769557][    T1] md: Waiting for all devices to be available before autodetect
[   49.777447][    T1] md: If you don't use raid, use raid=noautodetect
[   49.784213][    T1] md: Autodetecting RAID arrays.
[   49.789324][    T1] md: autorun ...
[   49.793191][    T1] md: ... autorun DONE.
[   49.912261][    T1] EXT4-fs (sda1): mounted filesystem 5941fea2-f5fa-4b4e-b5ef-9af118b27b95 ro with ordered data mode. Quota mode: none.
[   49.925661][    T1] VFS: Mounted root (ext4 filesystem) readonly on device 8:1.
[   49.949100][    T1] devtmpfs: mounted
[   50.204085][    T1] Freeing unused kernel image (initmem) memory: 36920K
[   50.216901][    T1] Write protecting the kernel read-only data: 260096k
[   50.263842][    T1] Freeing unused kernel image (rodata/data gap) memory: 1876K
[   51.884629][    T1] x86/mm: Checked W+X mappings: passed, no W+X pages found.
[   51.895285][    T1] x86/mm: Checking user space page tables
[   53.370836][    T1] x86/mm: Checked W+X mappings: passed, no W+X pages found.
[   53.379919][    T1] Failed to set sysctl parameter 'kernel.hung_task_all_cpu_backtrace=1': parameter not found
[   53.401312][    T1] Failed to set sysctl parameter 'max_rcu_stall_to_panic=1': parameter not found
[   53.413335][    T1] Run /sbin/init as init process
[   55.024257][ T4444] mount (4444) used greatest stack depth: 8112 bytes left
[   55.119469][ T4445] EXT4-fs (sda1): re-mounted 5941fea2-f5fa-4b4e-b5ef-9af118b27b95 r/w. Quota mode: none.
mount: mounting smackfs on /sys/fs/smackfs failed: No such file or directory
mount: mounting selinuxfs on /sys/fs/selinux failed: No such file or directory
[   55.460316][ T4448] mount (4448) used greatest stack depth: 5568 bytes left
Starting syslogd: OK
Starting acpid: OK
Starting klogd: OK
Running sysctl: OK
Populating /dev using udev: [   59.293786][ T4478] udevd[4478]: starting version 3.2.11
[   62.812014][ T4480] udevd[4480]: starting eudev-3.2.11
[   62.823661][ T4478] udevd (4478) used greatest stack depth: 5344 bytes left
[   96.252561][ T1219] net_ratelimit: 2 callbacks suppressed
[   96.252654][ T1219] aoe: packet could not be sent on lo.  consider increasing tx_queue_len
[   96.267801][ T1219] aoe: packet could not be sent on bond0.  consider increasing tx_queue_len
[   96.276910][ T1219] aoe: packet could not be sent on dummy0.  consider increasing tx_queue_len
[   96.286143][ T1219] aoe: packet could not be sent on eql.  consider increasing tx_queue_len
[   96.295161][ T1219] aoe: packet could not be sent on ifb0.  consider increasing tx_queue_len
[   96.304298][ T1219] aoe: packet could not be sent on ifb1.  consider increasing tx_queue_len
[   96.313312][ T1219] aoe: packet could not be sent on eth0.  consider increasing tx_queue_len
[   96.322319][ T1219] aoe: packet could not be sent on wlan0.  consider increasing tx_queue_len
[   96.331822][ T1219] aoe: packet could not be sent on wlan1.  consider increasing tx_queue_len
[   96.341035][ T1219] aoe: packet could not be sent on hwsim0.  consider increasing tx_queue_len
done
Starting system message bus: done
Starting iptables: OK
Starting network: OK
Starting dhcpcd...
dhcpcd-9.4.1 starting
dev: loaded udev
DUID 00:04:98:24:4c:28:99:7c:d9:70:fe:51:ca:fe:56:33:2c:7d
forked to background, child pid 4692
[  110.213007][ T4693] 8021q: adding VLAN 0 to HW filter on device bond0
[  110.255329][ T4693] eql: remember to turn off Van-Jacobson compression on your slave devices
Starting sshd: [  111.615530][   T10] cfg80211: failed to load regulatory.db
OK


syzkaller

syzkaller login: [  114.058251][    C0] =====================================================
[  114.065473][    C0] BUG: KMSAN: uninit-value in receive_buf+0x25e3/0x5fd0
[  114.072524][    C0]  receive_buf+0x25e3/0x5fd0
[  114.077324][    C0]  virtnet_poll+0xd1c/0x23c0
[  114.082110][    C0]  __napi_poll+0xe7/0x980
[  114.086745][    C0]  net_rx_action+0x82a/0x1850
[  114.091708][    C0]  handle_softirqs+0x1ce/0x800
[  114.096721][    C0]  __irq_exit_rcu+0x68/0x120
[  114.101495][    C0]  irq_exit_rcu+0x12/0x20
[  114.106116][    C0]  common_interrupt+0x94/0xa0
[  114.111003][    C0]  asm_common_interrupt+0x2b/0x40
[  114.116235][    C0]  virt_to_page_or_null+0x9b/0x150
[  114.121622][    C0]  kmsan_get_metadata+0x146/0x1d0
[  114.126851][    C0]  kmsan_get_shadow_origin_ptr+0x4d/0xb0
[  114.132755][    C0]  __msan_metadata_ptr_for_load_8+0x24/0x40
[  114.138838][    C0]  move_page_tables+0x22aa/0x3940
[  114.144062][    C0]  setup_arg_pages+0x1741/0x1eb0
[  114.149161][    C0]  load_elf_binary+0x186e/0x4e10
[  114.154310][    C0]  bprm_execve+0xc57/0x21c0
[  114.158971][    C0]  do_execveat_common+0xceb/0xd70
[  114.164231][    C0]  __x64_sys_execve+0xf4/0x130
[  114.169182][    C0]  x64_sys_call+0x164f/0x3b90
[  114.174097][    C0]  do_syscall_64+0xcd/0x1e0
[  114.178953][    C0]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  114.185159][    C0] 
[  114.187583][    C0] Uninit was created at:
[  114.191970][    C0]  __alloc_pages_noprof+0x9d6/0xe70
[  114.197429][    C0]  alloc_pages_mpol_noprof+0x299/0x990
[  114.203217][    C0]  alloc_pages_noprof+0x1bf/0x1e0
[  114.208521][    C0]  skb_page_frag_refill+0x2bf/0x7c0
[  114.214331][    C0]  virtnet_rq_alloc+0x43/0xbb0
[  114.219311][    C0]  try_fill_recv+0x3f0/0x2f50
[  114.224213][    C0]  virtnet_open+0x1cc/0xb00
[  114.228892][    C0]  __dev_open+0x546/0x6f0
[  114.233458][    C0]  __dev_change_flags+0x309/0x9a0
[  114.238699][    C0]  dev_change_flags+0x8e/0x1d0
[  114.243670][    C0]  devinet_ioctl+0x13ec/0x22c0
[  114.248707][    C0]  inet_ioctl+0x4bd/0x6d0
[  114.253223][    C0]  sock_do_ioctl+0xb7/0x540
[  114.257877][    C0]  sock_ioctl+0x727/0xd70
[  114.262296][    C0]  __se_sys_ioctl+0x261/0x450
[  114.267163][    C0]  __x64_sys_ioctl+0x96/0xe0
[  114.271913][    C0]  x64_sys_call+0x18c0/0x3b90
[  114.276861][    C0]  do_syscall_64+0xcd/0x1e0
[  114.281557][    C0]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  114.287691][    C0] 
[  114.290142][    C0] CPU: 0 PID: 4810 Comm: cmp Not tainted 6.10.0-rc2-syzkaller-00318-g68af0e6e57f1 #0
[  114.299891][    C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
[  114.310124][    C0] =====================================================
[  114.317210][    C0] Disabling lock debugging due to kernel taint
[  114.323590][    C0] Kernel panic - not syncing: kmsan.panic set ...
[  114.330063][    C0] CPU: 0 PID: 4810 Comm: cmp Tainted: G    B              6.10.0-rc2-syzkaller-00318-g68af0e6e57f1 #0
[  114.341090][    C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
[  114.351224][    C0] Call Trace:
[  114.354569][    C0]  <IRQ>
[  114.357458][    C0]  dump_stack_lvl+0x216/0x2d0
[  114.362339][    C0]  ? kmsan_get_shadow_origin_ptr+0x4d/0xb0
[  114.368256][    C0]  dump_stack+0x1e/0x30
[  114.372558][    C0]  panic+0x4e2/0xcd0
[  114.376579][    C0]  ? kmsan_get_metadata+0xa1/0x1d0
[  114.381828][    C0]  kmsan_report+0x2d5/0x2e0
[  114.386474][    C0]  ? __pfx_min_vruntime_cb_rotate+0x10/0x10
[  114.392494][    C0]  ? kmsan_internal_set_shadow_origin+0x69/0x100
[  114.398930][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.404232][    C0]  ? __msan_warning+0x95/0x120
[  114.409102][    C0]  ? receive_buf+0x25e3/0x5fd0
[  114.413993][    C0]  ? virtnet_poll+0xd1c/0x23c0
[  114.418899][    C0]  ? __napi_poll+0xe7/0x980
[  114.423521][    C0]  ? net_rx_action+0x82a/0x1850
[  114.428495][    C0]  ? handle_softirqs+0x1ce/0x800
[  114.433533][    C0]  ? __irq_exit_rcu+0x68/0x120
[  114.438422][    C0]  ? irq_exit_rcu+0x12/0x20
[  114.443046][    C0]  ? common_interrupt+0x94/0xa0
[  114.448005][    C0]  ? asm_common_interrupt+0x2b/0x40
[  114.453326][    C0]  ? virt_to_page_or_null+0x9b/0x150
[  114.458717][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.464012][    C0]  ? kmsan_get_shadow_origin_ptr+0x4d/0xb0
[  114.469951][    C0]  ? __msan_metadata_ptr_for_load_8+0x24/0x40
[  114.476138][    C0]  ? move_page_tables+0x22aa/0x3940
[  114.481443][    C0]  ? setup_arg_pages+0x1741/0x1eb0
[  114.487208][    C0]  ? load_elf_binary+0x186e/0x4e10
[  114.492542][    C0]  ? bprm_execve+0xc57/0x21c0
[  114.497428][    C0]  ? do_execveat_common+0xceb/0xd70
[  114.502965][    C0]  ? __x64_sys_execve+0xf4/0x130
[  114.508049][    C0]  ? x64_sys_call+0x164f/0x3b90
[  114.513049][    C0]  ? do_syscall_64+0xcd/0x1e0
[  114.517835][    C0]  ? entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  114.524271][    C0]  ? kmsan_internal_memmove_metadata+0x17b/0x230
[  114.530728][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.536028][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.541332][    C0]  ? page_to_skb+0xdae/0x1620
[  114.546091][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.551404][    C0]  __msan_warning+0x95/0x120
[  114.556099][    C0]  receive_buf+0x25e3/0x5fd0
[  114.560811][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.566222][    C0]  ? kmsan_get_shadow_origin_ptr+0x4d/0xb0
[  114.572325][    C0]  virtnet_poll+0xd1c/0x23c0
[  114.577052][    C0]  ? __pfx_virtnet_poll+0x10/0x10
[  114.582192][    C0]  __napi_poll+0xe7/0x980
[  114.586804][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.592127][    C0]  net_rx_action+0x82a/0x1850
[  114.596929][    C0]  ? sched_clock_cpu+0x55/0x870
[  114.601889][    C0]  ? __pfx_net_rx_action+0x10/0x10
[  114.607136][    C0]  handle_softirqs+0x1ce/0x800
[  114.612097][    C0]  __irq_exit_rcu+0x68/0x120
[  114.616825][    C0]  irq_exit_rcu+0x12/0x20
[  114.621255][    C0]  common_interrupt+0x94/0xa0
[  114.626143][    C0]  </IRQ>
[  114.629121][    C0]  <TASK>
[  114.632123][    C0]  asm_common_interrupt+0x2b/0x40
[  114.637277][    C0] RIP: 0010:virt_to_page_or_null+0x9b/0x150
[  114.643734][    C0] Code: d6 48 c1 ee 23 48 8b 34 f1 48 85 f6 74 13 48 89 d1 48 c1 e9 1b 0f b6 c9 48 c1 e1 04 48 01 ce eb 02 31 f6 65 ff 05 ad a1 c4 7d <48> 85 f6 74 09 4c 8b 06 41 f6 c0 02 75 17 31 c9 65 ff 0d 96 a1 c4
[  114.663636][    C0] RSP: 0018:ffff888115fa3560 EFLAGS: 00000282
[  114.669801][    C0] RAX: ffff8881a04798b0 RBX: ffff8881204798b0 RCX: 0000000000000240
[  114.678046][    C0] RDX: 00000001204798b0 RSI: ffff88813fff9240 RDI: ffff8881204798b0
[  114.686097][    C0] RBP: ffff888115fa3560 R08: ffffea000000000f R09: 0000000000000000
[  114.694353][    C0] R10: ffff8881157a3588 R11: 0000000000000004 R12: 00007ffffffff000
[  114.702427][    C0] R13: ffff88811759ccc0 R14: 0000000000000001 R15: ffff8881204798b0
[  114.710503][    C0]  kmsan_get_metadata+0x146/0x1d0
[  114.715665][    C0]  kmsan_get_shadow_origin_ptr+0x4d/0xb0
[  114.721472][    C0]  __msan_metadata_ptr_for_load_8+0x24/0x40
[  114.727581][    C0]  move_page_tables+0x22aa/0x3940
[  114.732810][    C0]  setup_arg_pages+0x1741/0x1eb0
[  114.737898][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.743211][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.748534][    C0]  ? kmsan_internal_set_shadow_origin+0x69/0x100
[  114.754977][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.760321][    C0]  load_elf_binary+0x186e/0x4e10
[  114.765360][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.770982][    C0]  ? kmsan_internal_set_shadow_origin+0x69/0x100
[  114.777440][    C0]  ? kmsan_internal_unpoison_memory+0x14/0x20
[  114.783631][    C0]  ? load_elf_binary+0x1331/0x4e10
[  114.788932][    C0]  ? kmsan_get_metadata+0x146/0x1d0
[  114.794247][    C0]  ? __pfx_load_elf_binary+0x10/0x10
[  114.799718][    C0]  bprm_execve+0xc57/0x21c0
[  114.804338][    C0]  do_execveat_common+0xceb/0xd70
[  114.809485][    C0]  __x64_sys_execve+0xf4/0x130
[  114.814370][    C0]  x64_sys_call+0x164f/0x3b90
[  114.819190][    C0]  do_syscall_64+0xcd/0x1e0
[  114.823875][    C0]  ? clear_bhb_loop+0x25/0x80
[  114.828744][    C0]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
[  114.834741][    C0] RIP: 0033:0x7febec525ef7
[  114.839238][    C0] Code: Unable to access opcode bytes at 0x7febec525ecd.
[  114.846321][    C0] RSP: 002b:00007ffee08c4918 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
[  114.855113][    C0] RAX: ffffffffffffffda RBX: 000055e293558020 RCX: 00007febec525ef7
[  114.863169][    C0] RDX: 000055e293558048 RSI: 000055e293558020 RDI: 000055e2935580d0
[  114.871237][    C0] RBP: 000055e2935580d0 R08: 000055e2935580d9 R09: 00007ffee08c8ecb
[  114.879289][    C0] R10: 0000000000000008 R11: 0000000000000246 R12: 000055e293558048
[  114.887358][    C0] R13: 00007febec6d3904 R14: 000055e293558048 R15: 0000000000000000
[  114.895462][    C0]  </TASK>
[  114.898839][    C0] Kernel Offset: disabled
[  114.903237][    C0] Rebooting in 86400 seconds..


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-build3593741732=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 25905f5d0a
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/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
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=25905f5d0a2a7883bd33491997556193582c6059 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240301-171218'" "-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=25905f5d0a2a7883bd33491997556193582c6059 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240301-171218'" "-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=25905f5d0a2a7883bd33491997556193582c6059 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240301-171218'" "-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=\"25905f5d0a2a7883bd33491997556193582c6059\"


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=16a96dce980000


Tested on:

commit:         68af0e6e hfs: fix to initialize fields of hfs_inode_in..
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git misc
kernel config:  https://syzkaller.appspot.com/x/.config?x=b7d07bfd0c305fe4
dashboard link: https://syzkaller.appspot.com/bug?extid=3ae6be33a50b5aae4dab
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.