Re: [syzbot] [hfs?] memory leak in hfs_init_fs_context

[syzbot <syzbot+ad45f827c88778ff7df6@syzkaller.appspotmail.com>]

Hello,

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

SYZFAIL: failed to recv rpc

SYZFAIL: failed to recv rpc
fd=3 want=4 recv=0 n=0 (errno 9: Bad file descriptor)


Warning: Permanently added '10.128.1.132' (ED25519) to the list of known hosts.
2025/11/14 04:25:22 parsed 1 programs
[   38.568834][ T5812] cgroup: Unknown subsys name 'net'
[   38.681579][ T5812] cgroup: Unknown subsys name 'cpuset'
[   38.687948][ T5812] cgroup: Unknown subsys name 'rlimit'
Setting up swapspace version 1, size = 127995904 bytes
[   47.206806][ T5812] Adding 124996k swap on ./swap-file.  Priority:0 extents:1 across:124996k 
[   48.634442][ T5821] soft_limit_in_bytes is deprecated and will be removed. Please report your usecase to linux-mm@kvack.org if you depend on this functionality.
[   49.057992][   T31] wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
[   49.068464][   T31] wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50
[   49.080224][   T12] wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
[   49.088091][   T12] wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
[   49.177421][ T5870] chnl_net:caif_netlink_parms(): no params data found
[   49.197720][ T5870] bridge0: port 1(bridge_slave_0) entered blocking state
[   49.205546][ T5870] bridge0: port 1(bridge_slave_0) entered disabled state
[   49.212806][ T5870] bridge_slave_0: entered allmulticast mode
[   49.219093][ T5870] bridge_slave_0: entered promiscuous mode
[   49.226954][ T5870] bridge0: port 2(bridge_slave_1) entered blocking state
[   49.234019][ T5870] bridge0: port 2(bridge_slave_1) entered disabled state
[   49.241114][ T5870] bridge_slave_1: entered allmulticast mode
[   49.247273][ T5870] bridge_slave_1: entered promiscuous mode
[   49.257812][ T5870] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link
[   49.267520][ T5870] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link
[   49.283802][ T5870] team0: Port device team_slave_0 added
[   49.289970][ T5870] team0: Port device team_slave_1 added
[   49.299659][ T5870] batman_adv: batadv0: Adding interface: batadv_slave_0
[   49.306737][ T5870] batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1532 would solve the problem.
[   49.332781][ T5870] batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active
[   49.344098][ T5870] batman_adv: batadv0: Adding interface: batadv_slave_1
[   49.351244][ T5870] batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1532 would solve the problem.
[   49.377242][ T5870] batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active
[   49.395484][ T5870] hsr_slave_0: entered promiscuous mode
[   49.401255][ T5870] hsr_slave_1: entered promiscuous mode
[   49.429633][ T5870] netdevsim netdevsim0 netdevsim0: renamed from eth0
[   49.437511][ T5870] netdevsim netdevsim0 netdevsim1: renamed from eth1
[   49.445536][ T5870] netdevsim netdevsim0 netdevsim2: renamed from eth2
[   49.453283][ T5870] netdevsim netdevsim0 netdevsim3: renamed from eth3
[   49.466311][ T5870] bridge0: port 2(bridge_slave_1) entered blocking state
[   49.473549][ T5870] bridge0: port 2(bridge_slave_1) entered forwarding state
[   49.480828][ T5870] bridge0: port 1(bridge_slave_0) entered blocking state
[   49.487888][ T5870] bridge0: port 1(bridge_slave_0) entered forwarding state
[   49.506659][ T5870] 8021q: adding VLAN 0 to HW filter on device bond0
[   49.515852][   T31] bridge0: port 1(bridge_slave_0) entered disabled state
[   49.523955][   T31] bridge0: port 2(bridge_slave_1) entered disabled state
[   49.533442][ T5870] 8021q: adding VLAN 0 to HW filter on device team0
[   49.541649][   T31] bridge0: port 1(bridge_slave_0) entered blocking state
[   49.548678][   T31] bridge0: port 1(bridge_slave_0) entered forwarding state
[   49.557491][ T4775] bridge0: port 2(bridge_slave_1) entered blocking state
[   49.564551][ T4775] bridge0: port 2(bridge_slave_1) entered forwarding state
[   49.609789][ T5870] 8021q: adding VLAN 0 to HW filter on device batadv0
[   49.624774][ T5870] veth0_vlan: entered promiscuous mode
[   49.632240][ T5870] veth1_vlan: entered promiscuous mode
[   49.642980][ T5870] veth0_macvtap: entered promiscuous mode
[   49.649568][ T5870] veth1_macvtap: entered promiscuous mode
[   49.658587][ T5870] batman_adv: batadv0: Interface activated: batadv_slave_0
[   49.667884][ T5870] batman_adv: batadv0: Interface activated: batadv_slave_1
[   49.677213][ T4775] netdevsim netdevsim0 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0
[   49.685998][ T4775] netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
[   49.696282][ T4775] netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
[   49.705044][ T4775] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
[   49.739615][ T5893] Bluetooth: hci0: unexpected cc 0x0c03 length: 249 > 1
[   49.746762][ T5893] Bluetooth: hci0: unexpected cc 0x1003 length: 249 > 9
[   49.754212][ T5893] Bluetooth: hci0: unexpected cc 0x1001 length: 249 > 9
[   49.761539][ T5893] Bluetooth: hci0: unexpected cc 0x0c23 length: 249 > 4
[   49.768803][ T5893] Bluetooth: hci0: unexpected cc 0x0c38 length: 249 > 2
[   49.777506][   T12] netdevsim netdevsim0 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
[   49.811620][   T12] netdevsim netdevsim0 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
[   49.872308][   T12] netdevsim netdevsim0 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
[   49.932883][   T12] netdevsim netdevsim0 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
2025/11/14 04:25:36 executed programs: 0
[   52.871628][   T12] bridge_slave_1: left allmulticast mode
[   52.877509][   T12] bridge_slave_1: left promiscuous mode
[   52.883233][   T12] bridge0: port 2(bridge_slave_1) entered disabled state
[   52.890693][   T12] bridge_slave_0: left allmulticast mode
[   52.896320][   T12] bridge_slave_0: left promiscuous mode
[   52.902081][   T12] bridge0: port 1(bridge_slave_0) entered disabled state
[   52.942851][   T12] bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
[   52.951925][   T12] bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
[   52.960999][   T12] bond0 (unregistering): Released all slaves
[   53.054718][   T12] hsr_slave_0: left promiscuous mode
[   53.060223][   T12] hsr_slave_1: left promiscuous mode
[   53.065682][   T12] batman_adv: batadv0: Interface deactivated: batadv_slave_0
[   53.073538][   T12] batman_adv: batadv0: Removing interface: batadv_slave_0
[   53.081030][   T12] batman_adv: batadv0: Interface deactivated: batadv_slave_1
[   53.088412][   T12] batman_adv: batadv0: Removing interface: batadv_slave_1
[   53.097247][   T12] veth1_macvtap: left promiscuous mode
[   53.102787][   T12] veth0_macvtap: left promiscuous mode
[   53.108333][   T12] veth1_vlan: left promiscuous mode
[   53.113692][   T12] veth0_vlan: left promiscuous mode
[   53.146117][   T12] team0 (unregistering): Port device team_slave_1 removed
[   53.154944][   T12] team0 (unregistering): Port device team_slave_0 removed
[   55.775892][ T5893] Bluetooth: hci0: unexpected cc 0x0c03 length: 249 > 1
[   55.783123][ T5893] Bluetooth: hci0: unexpected cc 0x1003 length: 249 > 9
[   55.790299][ T5893] Bluetooth: hci0: unexpected cc 0x1001 length: 249 > 9
[   55.797638][ T5893] Bluetooth: hci0: unexpected cc 0x0c23 length: 249 > 4
[   55.805009][ T5893] Bluetooth: hci0: unexpected cc 0x0c38 length: 249 > 2
[   55.842807][ T5987] chnl_net:caif_netlink_parms(): no params data found
[   55.861642][ T5987] bridge0: port 1(bridge_slave_0) entered blocking state
[   55.868694][ T5987] bridge0: port 1(bridge_slave_0) entered disabled state
[   55.876286][ T5987] bridge_slave_0: entered allmulticast mode
[   55.882536][ T5987] bridge_slave_0: entered promiscuous mode
[   55.888863][ T5987] bridge0: port 2(bridge_slave_1) entered blocking state
[   55.896054][ T5987] bridge0: port 2(bridge_slave_1) entered disabled state
[   55.903160][ T5987] bridge_slave_1: entered allmulticast mode
[   55.909310][ T5987] bridge_slave_1: entered promiscuous mode
[   55.921259][ T5987] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link
[   55.931363][ T5987] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link
[   55.946114][ T5987] team0: Port device team_slave_0 added
[   55.952406][ T5987] team0: Port device team_slave_1 added
[   55.962372][ T5987] batman_adv: batadv0: Adding interface: batadv_slave_0
[   55.969330][ T5987] batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1532 would solve the problem.
[   55.995474][ T5987] batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active
[   56.006426][ T5987] batman_adv: batadv0: Adding interface: batadv_slave_1
[   56.013527][ T5987] batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1532 would solve the problem.
[   56.039738][ T5987] batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active
[   56.056635][ T5987] hsr_slave_0: entered promiscuous mode
[   56.062419][ T5987] hsr_slave_1: entered promiscuous mode
[   56.253249][ T5987] netdevsim netdevsim0 netdevsim0: renamed from eth0
[   56.261855][ T5987] netdevsim netdevsim0 netdevsim1: renamed from eth1
[   56.269702][ T5987] netdevsim netdevsim0 netdevsim2: renamed from eth2
[   56.278553][ T5987] netdevsim netdevsim0 netdevsim3: renamed from eth3
[   56.294272][ T5987] bridge0: port 2(bridge_slave_1) entered blocking state
[   56.301460][ T5987] bridge0: port 2(bridge_slave_1) entered forwarding state
[   56.308739][ T5987] bridge0: port 1(bridge_slave_0) entered blocking state
[   56.315923][ T5987] bridge0: port 1(bridge_slave_0) entered forwarding state
[   56.338321][ T5987] 8021q: adding VLAN 0 to HW filter on device bond0
[   56.348077][   T31] bridge0: port 1(bridge_slave_0) entered disabled state
[   56.356081][   T31] bridge0: port 2(bridge_slave_1) entered disabled state
[   56.366155][ T5987] 8021q: adding VLAN 0 to HW filter on device team0
[   56.374820][   T49] bridge0: port 1(bridge_slave_0) entered blocking state
[   56.381909][   T49] bridge0: port 1(bridge_slave_0) entered forwarding state
[   56.400099][   T49] bridge0: port 2(bridge_slave_1) entered blocking state
[   56.407204][   T49] bridge0: port 2(bridge_slave_1) entered forwarding state
[   56.458214][ T5987] 8021q: adding VLAN 0 to HW filter on device batadv0
[   56.477365][ T5987] veth0_vlan: entered promiscuous mode
[   56.485374][ T5987] veth1_vlan: entered promiscuous mode
[   56.498620][ T5987] veth0_macvtap: entered promiscuous mode
[   56.506001][ T5987] veth1_macvtap: entered promiscuous mode
[   56.516830][ T5987] batman_adv: batadv0: Interface activated: batadv_slave_0
[   56.526501][ T5987] batman_adv: batadv0: Interface activated: batadv_slave_1
[   56.536259][   T31] netdevsim netdevsim0 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0
[   56.554454][   T31] netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
[   56.571101][   T49] wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
[   56.579028][   T49] wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50
[   56.589211][   T31] netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
SYZFAIL: failed to recv rpc
fd=3 want=4 recv=0 n=0 (errno 9: Bad file descriptor)
[   56.602245][   T35] wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
[   56.602375][   T31] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
[   56.610080][   T35] wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50


syzkaller build log:
go env (err=<nil>)
AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE='auto'
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build2609802501=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod'
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'
GOTELEMETRY='local'
GOTELEMETRYDIR='/syzkaller/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.24.4'
GOWORK=''
PKG_CONFIG='pkg-config'

git status (err=<nil>)
HEAD detached at 4e1406b4def
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}}' -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=4e1406b4defac0e2a9d9424c70706f79a7750cf3 -X github.com/google/syzkaller/prog.gitRevisionDate=20251106-151142"  ./sys/syz-sysgen | grep -q false || go install -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=4e1406b4defac0e2a9d9424c70706f79a7750cf3 -X github.com/google/syzkaller/prog.gitRevisionDate=20251106-151142"  ./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=4e1406b4defac0e2a9d9424c70706f79a7750cf3 -X github.com/google/syzkaller/prog.gitRevisionDate=20251106-151142"  -o ./bin/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 -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 -std=c++17 -I. -Iexecutor/_include   -DGOOS_linux=1 -DGOARCH_amd64=1 \
	-DHOSTGOOS_linux=1 -DGIT_REVISION=\"4e1406b4defac0e2a9d9424c70706f79a7750cf3\"
/usr/bin/ld: /tmp/ccG1R0tu.o: in function `Connection::Connect(char const*, char const*)':
executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEPKcS1_]+0x104): warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
./tools/check-syzos.sh 2>/dev/null



Tested on:

commit:         6da43bbe Merge tag 'vfio-v6.18-rc6' of https://github...
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=cb128cd5cb439809
dashboard link: https://syzkaller.appspot.com/bug?extid=ad45f827c88778ff7df6
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16ceb60a580000