ci2 starts bisection 2026-10-15 11:40:31.888753947 +0000 UTC m=+39162.662569373 bisecting fixing commit since 2f1baf1fc8929e6c48370be543ad028ac7ad4131 building syzkaller on 6f9b3e8923f9499358620f27edb65748dd0005ea ensuring issue is reproducible on original commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: c29acb59a62af15b561ee8f3fd69a0322b17f2a96bdbfcc3b7d86984bb702d7c run #0: crashed: WARNING: refcount bug in config_item_get run #1: crashed: WARNING: refcount bug in config_item_get run #2: crashed: WARNING: refcount bug in config_item_get run #3: crashed: WARNING: refcount bug in config_item_get run #4: crashed: WARNING: refcount bug in config_item_get run #5: crashed: WARNING: refcount bug in config_item_get run #6: crashed: WARNING: refcount bug in config_item_get run #7: crashed: WARNING: refcount bug in config_item_get run #8: crashed: WARNING: refcount bug in config_item_get run #9: crashed: KASAN: slab-use-after-free Read in configfs_dirent_is_ready run #10: crashed: WARNING: refcount bug in config_item_get run #11: crashed: WARNING: refcount bug in config_item_get run #12: crashed: WARNING: refcount bug in config_item_get run #13: crashed: WARNING: refcount bug in config_item_get run #14: crashed: WARNING: refcount bug in config_item_get run #15: crashed: WARNING: refcount bug in config_item_get run #16: crashed: WARNING: refcount bug in config_item_get run #17: crashed: KASAN: slab-use-after-free Read in configfs_dirent_is_ready run #18: crashed: WARNING: refcount bug in config_item_get run #19: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] check whether we can drop unnecessary instrumentation disabling configs for [hang memleak ubsan kasan locking atomic_sleep], they are not needed testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 9d2c926eb6e4206154528ef8358aec8e7215dfa01e2644bcd80d80514240f88b all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] the bug reproduces without the instrumentation disabling configs for [kasan locking atomic_sleep hang memleak ubsan], they are not needed kconfig minimization: base=4169 full=8398 leaves diff=2092 split chunks (needed=false): <2092> split chunk #0 of len 2092 into 5 parts testing without sub-chunk 1/5 disabling configs for [hang memleak ubsan kasan locking atomic_sleep], they are not needed testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: dab57209015f95e449acc69b81ad1a273bdf950d4236d4541fa7d0b0914b99de all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [locking atomic_sleep hang memleak ubsan kasan], they are not needed testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 7fff2bf7006fd25b743674ce9747a64f4091e7449dcb16ecc22f44941d8f0a80 all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] the chunk can be dropped testing without sub-chunk 3/5 disabling configs for [locking atomic_sleep hang memleak ubsan kasan], they are not needed testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 0184854e95a5d512e6dfe98c7f0ff65ecb992e3a514f162b7329e8a908653030 all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] the chunk can be dropped testing without sub-chunk 4/5 disabling configs for [kasan locking atomic_sleep hang memleak ubsan], they are not needed testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 80fd2878f5138a740a809ee5f6959d845d92054d2f194bce20297396a65b2fb4 all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] the chunk can be dropped testing without sub-chunk 5/5 disabling configs for [locking atomic_sleep hang memleak ubsan kasan], they are not needed testing commit 2f1baf1fc8929e6c48370be543ad028ac7ad4131 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 1804218b01173c6110927722a16aafd60aa5a2f22ab58d96f27915a00a0695cf all runs: OK false negative chance: 0.000 minimized to 416 configs; suspects: [ATM BCMA BLK_DEV_ZONED BPF_SYSCALL CARDBUS CFG80211 CFG80211_WEXT COMMON_CLK CONTIG_ALLOC DVB_CORE EXTCON GPIOLIB HID_ZEROPLUS I2C_MUX IIO IOMMUFD KVM KVM_INTEL LIBNVDIMM MEDIA_ANALOG_TV_SUPPORT MEDIA_CAMERA_SUPPORT MEDIA_CEC_SUPPORT MEDIA_CONTROLLER MEDIA_DIGITAL_TV_SUPPORT MEDIA_RADIO_SUPPORT MEDIA_SDR_SUPPORT MEDIA_SUPPORT MEDIA_TEST_SUPPORT MEDIA_USB_SUPPORT MEMORY_HOTPLUG MEMORY_HOTREMOVE MFD_VIPERBOARD NOP_USB_XCEIV PARPORT PCCARD PCMCIA PHONET RADIO_ADAPTERS RADIO_SI470X RADIO_SI4713 RC_CORE RFKILL SND SOUND SPI SSB TAP TARGET_CORE TUN USB_AMD5536UDC USB_ATM USB_CHIPIDEA USB_CHIPIDEA_GENERIC USB_CHIPIDEA_HOST USB_CHIPIDEA_MSM USB_CHIPIDEA_NPCM USB_CHIPIDEA_PCI USB_CHIPIDEA_UDC USB_CONFIGFS USB_CONFIGFS_ACM USB_CONFIGFS_ECM USB_CONFIGFS_ECM_SUBSET USB_CONFIGFS_EEM USB_CONFIGFS_F_FS USB_CONFIGFS_F_HID USB_CONFIGFS_F_LB_SS USB_CONFIGFS_F_MIDI USB_CONFIGFS_F_MIDI2 USB_CONFIGFS_F_PRINTER USB_CONFIGFS_F_TCM USB_CONFIGFS_F_UAC1 USB_CONFIGFS_F_UAC1_LEGACY USB_CONFIGFS_F_UAC2 USB_CONFIGFS_F_UVC USB_CONFIGFS_MASS_STORAGE USB_CONFIGFS_NCM USB_CONFIGFS_OBEX USB_CONFIGFS_PHONET USB_CONFIGFS_RNDIS USB_CONFIGFS_SERIAL USB_CONN_GPIO USB_CXACRU USB_CYPRESS_CY7C63 USB_CYTHERM USB_DSBR USB_DUMMY_HCD USB_DWC2 USB_DWC2_HOST USB_DWC2_PCI USB_DWC3 USB_DWC3_GADGET USB_DWC3_GENERIC_PLAT USB_DWC3_HAPS USB_DWC3_OF_SIMPLE USB_DWC3_PCI USB_DWC3_ULPI USB_DYNAMIC_MINORS USB_EG20T USB_EHCI_FSL USB_EHCI_HCD_PLATFORM USB_EHCI_ROOT_HUB_TT USB_EHSET_TEST_FIXTURE USB_EMI26 USB_EMI62 USB_EPSON2888 USB_EZUSB_FX2 USB_FEW_INIT_RETRIES USB_F_ACM USB_F_ECM USB_F_EEM USB_F_FS USB_F_HID USB_F_MASS_STORAGE USB_F_MIDI USB_F_MIDI2 USB_F_NCM USB_F_OBEX USB_F_PHONET USB_F_PRINTER USB_F_RNDIS USB_F_SERIAL USB_F_SS_LB USB_F_SUBSET USB_F_TCM USB_F_UAC1 USB_F_UAC1_LEGACY USB_F_UAC2 USB_F_UVC USB_GADGET USB_GADGETFS USB_GADGET_DEBUG_FILES USB_GADGET_DEBUG_FS USB_GL860 USB_GOKU USB_GR_UDC USB_GSPCA USB_GSPCA_BENQ USB_GSPCA_CONEX 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USB_ISP1761_UDC USB_KAWETH USB_KC2190 USB_KEENE USB_LAN78XX USB_LCD USB_LD USB_LEDS_TRIGGER_USBPORT USB_LED_TRIG USB_LEGOTOWER USB_LGM_PHY USB_LIBCOMPOSITE USB_LINK_LAYER_TEST USB_M5602 USB_MA901 USB_MAX3420_UDC USB_MAX3421_HCD USB_MDC800 USB_MICROTEK USB_MR800 USB_MSI2500 USB_MUSB_DUAL_ROLE USB_MUSB_HDRC USB_NET2280 USB_NET_AQC111 USB_NET_AX88179_178A USB_NET_AX8817X USB_NET_CDCETHER USB_NET_CDC_EEM USB_NET_CDC_MBIM USB_NET_CDC_NCM USB_NET_CDC_SUBSET USB_NET_CDC_SUBSET_ENABLE USB_NET_CH9200 USB_NET_CX82310_ETH USB_NET_DM9601 USB_NET_GL620A USB_NET_HUAWEI_CDC_NCM USB_NET_INT51X1 USB_NET_KALMIA USB_NET_MCS7830 USB_NET_NET1080 USB_NET_PLUSB USB_NET_QMI_WWAN USB_NET_RNDIS_HOST USB_NET_SMSC75XX USB_NET_SMSC95XX USB_NET_SR9700 USB_NET_SR9800 USB_NET_ZAURUS USB_OHCI_HCD_PLATFORM USB_OTG USB_OTG_FSM USB_OXU210HP_HCD USB_PEGASUS USB_PULSE8_CEC USB_PWC USB_PWC_INPUT_EVDEV USB_PXA27X USB_R8A66597 USB_R8A66597_HCD USB_RAINSHADOW_CEC USB_RAREMONO USB_RAW_GADGET USB_RTL8150 USB_RTL8152 USB_RTL8153_ECM USB_S2255 USB_SERIAL USB_SERIAL_AIRCABLE USB_SERIAL_ARK3116 USB_SERIAL_BELKIN USB_SERIAL_CH341 USB_SERIAL_CONSOLE USB_SERIAL_CP210X USB_SERIAL_CYBERJACK USB_SERIAL_CYPRESS_M8 USB_SERIAL_DEBUG USB_SERIAL_DIGI_ACCELEPORT USB_SERIAL_EDGEPORT USB_SERIAL_EDGEPORT_TI USB_SERIAL_EMPEG USB_SERIAL_F81232 USB_SERIAL_F8153X USB_SERIAL_FTDI_SIO USB_SERIAL_GARMIN USB_SERIAL_GENERIC USB_SERIAL_IPAQ USB_SERIAL_IPW USB_SERIAL_IR USB_SERIAL_IUU USB_SERIAL_KEYSPAN USB_SERIAL_KEYSPAN_PDA USB_SERIAL_KLSI USB_SERIAL_KOBIL_SCT USB_SERIAL_MCT_U232 USB_SERIAL_METRO USB_SERIAL_MOS7715_PARPORT USB_SERIAL_MOS7720 USB_SERIAL_MOS7840 USB_SERIAL_MXUPORT USB_SERIAL_NAVMAN USB_SERIAL_OMNINET USB_SERIAL_OPTICON USB_SERIAL_OPTION USB_SERIAL_OTI6858 USB_SERIAL_PL2303 USB_SERIAL_QCAUX USB_SERIAL_QT2 USB_SERIAL_QUALCOMM USB_SERIAL_SAFE USB_SERIAL_SIERRAWIRELESS USB_SERIAL_SIMPLE USB_SERIAL_SPCP8X5 USB_SERIAL_SSU100 USB_SERIAL_SYMBOL USB_SERIAL_TI USB_SERIAL_UPD78F0730 USB_SERIAL_VISOR USB_SERIAL_WHITEHEAT USB_SERIAL_WISHBONE USB_SERIAL_WWAN USB_SERIAL_XR USB_SERIAL_XSENS_MT USB_SEVSEG USB_SI470X USB_SI4713 USB_SIERRA_NET USB_SISUSBVGA USB_SL811_CS USB_SL811_HCD USB_SL811_HCD_ISO USB_SNP_CORE USB_SPEEDTOUCH USB_STORAGE_ALAUDA USB_STORAGE_CYPRESS_ATACB USB_STORAGE_DATAFAB USB_STORAGE_ENE_UB6250 USB_STORAGE_FREECOM USB_STORAGE_ISD200 USB_STORAGE_JUMPSHOT USB_STORAGE_KARMA USB_STORAGE_ONETOUCH USB_STORAGE_SDDR09 USB_STORAGE_SDDR55 USB_STORAGE_USBAT USB_STV06XX USB_TEST USB_TMC USB_TRANCEVIBRATOR USB_UAS USB_UEAGLEATM USB_ULPI_BUS USB_USBNET USB_USS720 USB_U_AUDIO USB_U_ETHER USB_U_SERIAL USB_VIDEO_CLASS USB_VIDEO_CLASS_INPUT_EVDEV USB_VL600 USB_WDM USB_XHCI_DBGCAP USB_XHCI_PCI_RENESAS USB_XHCI_PLATFORM USB_XUSBATM USB_YUREX USERFAULTFD USERIO USER_RETURN_NOTIFIER UVC_COMMON U_SERIAL_CONSOLE V4L2_MEM2MEM_DEV V4L_TEST_DRIVERS VALIDATE_FS_PARSER VDPA VDPA_SIM VDPA_SIM_BLOCK VDPA_SIM_NET VETH VFIO VFIO_DEVICE_CDEV VFIO_PCI VFIO_PCI_CORE VFIO_PCI_INTX VFIO_VIRQFD VGASTATE VHOST VHOST_CROSS_ENDIAN_LEGACY VHOST_IOTLB VHOST_NET VHOST_RING VHOST_TASK VHOST_VDPA VHOST_VSOCK VIDEO VIDEOBUF2_CORE VIDEOBUF2_DMA_CONTIG VIDEOBUF2_DMA_SG VIDEOBUF2_MEMOPS VIDEOBUF2_V4L2 VIDEOBUF2_VMALLOC VIDEOMODE_HELPERS VIDEO_AU0828 VIDEO_AU0828_RC VIDEO_AU0828_V4L2 VIDEO_CS53L32A VIDEO_CX231XX VIDEO_CX231XX_ALSA VIDEO_CX231XX_DVB VIDEO_CX231XX_RC VIDEO_CX2341X VIDEO_CX25840 VIDEO_DEV VIDEO_EM28XX VIDEO_EM28XX_ALSA VIDEO_EM28XX_DVB VIDEO_EM28XX_RC VIDEO_EM28XX_V4L2 VIDEO_GO7007 VIDEO_GO7007_LOADER VIDEO_GO7007_USB VIDEO_GO7007_USB_S2250_BOARD VIDEO_HDPVR VIDEO_MSP3400 VIDEO_PVRUSB2 VIDEO_PVRUSB2_DVB VIDEO_PVRUSB2_SYSFS VIDEO_SAA711X VIDEO_STK1160 VIDEO_TUNER VIDEO_TVEEPROM VIDEO_USBTV VIDEO_V4L2_I2C VIDEO_V4L2_SUBDEV_API VIDEO_V4L2_TPG VIDEO_VICODEC VIDEO_VIM2M VIDEO_VIMC VIDEO_VIVID VIDEO_VIVID_CEC VIDEO_WM8775 VIPERBOARD_ADC VIRTIO_BALLOON VIRTIO_DMA_SHARED_BUFFER VIRTIO_MEM VIRTIO_MMIO VIRTIO_MMIO_CMDLINE_DEVICES VIRTIO_PMEM VIRTIO_VDPA VIRTIO_VSOCKETS VIRTIO_VSOCKETS_COMMON VIRT_WIFI VIRT_XFER_TO_GUEST_WORK VLAN_8021Q VLAN_8021Q_GVRP VLAN_8021Q_MVRP VMWARE_VMCI VMXNET3 VP_VDPA VSOCKETS VSOCKETS_DIAG VSOCKETS_LOOPBACK VSOCKMON VT_HW_CONSOLE_BINDING WANT_DEV_COREDUMP WEXT_CORE WEXT_PROC WIREGUARD WIRELESS WLAN WLAN_VENDOR_ADMTEK WLAN_VENDOR_SILABS X86_FRED X86_SGX X86_SGX_KVM X86_USER_SHADOW_STACK XDP_SOCKETS XDP_SOCKETS_DIAG XFRM_ESPINTCP XFRM_INTERFACE XFRM_IPCOMP XFRM_MIGRATE XFRM_OFFLOAD XFRM_STATISTICS XFRM_SUB_POLICY XFRM_USER_COMPAT XFS_BTREE_IN_MEM XFS_DRAIN_INTENTS XFS_FS XFS_LIVE_HOOKS XFS_MEMORY_BUFS XFS_ONLINE_REPAIR XFS_ONLINE_SCRUB XFS_POSIX_ACL XFS_QUOTA XFS_RT XILLYBUS_CLASS XILLYUSB XOR_BLOCKS XOR_BLOCKS_ARCH YENTA YENTA_ENE_TUNE YENTA_O2 YENTA_RICOH YENTA_TI YENTA_TOSHIBA ZEROPLUS_FF ZLIB_DEFLATE ZONEFS_FS ZRAM ZRAM_BACKEND_FORCE_LZO ZRAM_BACKEND_LZO ZRAM_DEF_COMP_LZO ZSMALLOC ZSTD_COMPRESS ZSWAP ZSWAP_COMPRESSOR_DEFAULT_842 ZSWAP_DEFAULT_ON ZSWAP_SHRINKER_DEFAULT_ON] disabling configs for [memleak ubsan kasan locking atomic_sleep hang], they are not needed testing current HEAD 0fcb05b72344f40806cbe810de8872f1698bf053 testing commit 0fcb05b72344f40806cbe810de8872f1698bf053 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 1019ee5d5fcf625ce5c9bffd1472798756f9c60a0cfc60ee870d06c7e2d89775 all runs: OK false negative chance: 0.000 # git bisect start 0fcb05b72344f40806cbe810de8872f1698bf053 2f1baf1fc8929e6c48370be543ad028ac7ad4131 Bisecting: 11090 revisions left to test after this (roughly 13 steps) [56ea4e86832d8abe8930394473566c194d189f85] nstree: check listing permission before taking a namespace reference determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit 56ea4e86832d8abe8930394473566c194d189f85 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 0568294e211f6c55dfa20b936d2c34362d7348f12eba4ba3dfa9d6cee558490c all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good 56ea4e86832d8abe8930394473566c194d189f85 Bisecting: 5661 revisions left to test after this (roughly 13 steps) [70f5376dbdefa675adec0800e9f21f20a0dc0cbd] Merge tag 'tty-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit 70f5376dbdefa675adec0800e9f21f20a0dc0cbd gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: a9d821d813d9a5ef9fd16e8f7a12d9fadcff7a3397fb72c73f8d236e847a7aae all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good 70f5376dbdefa675adec0800e9f21f20a0dc0cbd Bisecting: 2873 revisions left to test after this (roughly 12 steps) [3d399224425573875b6f6f1181bd8cf9a28cc7d1] namespace: simplify disconnect_mount() determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit 3d399224425573875b6f6f1181bd8cf9a28cc7d1 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 8fa1bcb60894538233bbd324669f02a70a8df9bf81422c93d5fb2342dbd8575d all runs: OK false negative chance: 0.000 # git bisect bad 3d399224425573875b6f6f1181bd8cf9a28cc7d1 Bisecting: 1303 revisions left to test after this (roughly 11 steps) [1b78070aaef63512688aebfbc82365ef9d6660f1] Merge tag 'net-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit 1b78070aaef63512688aebfbc82365ef9d6660f1 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 7645a68248ba7f43ef807c585ce84e0f9dca272033dbb40748352faf54a776da all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good 1b78070aaef63512688aebfbc82365ef9d6660f1 Bisecting: 696 revisions left to test after this (roughly 9 steps) [8ab1afb2eb246ab15b301cd255b5943d208a93c1] Merge tag 'for-7.3/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm determine whether the revision contains the guilty commit revision 1b78070aaef63512688aebfbc82365ef9d6660f1 crashed and is reachable testing commit 8ab1afb2eb246ab15b301cd255b5943d208a93c1 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: ff0b1ed678dcc7fa4f80ce5f383a71096d6f6926b324b99df36e16635a6c0ca2 all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good 8ab1afb2eb246ab15b301cd255b5943d208a93c1 Bisecting: 355 revisions left to test after this (roughly 9 steps) [0d9ff90a5422cc7509258aaaba1e7481df4d332a] Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi determine whether the revision contains the guilty commit revision 70f5376dbdefa675adec0800e9f21f20a0dc0cbd crashed and is reachable testing commit 0d9ff90a5422cc7509258aaaba1e7481df4d332a gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 92c76675df17e1d25815e061ad4a8c86f4c4232ad6f669f2cde5c50e5890e83f all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good 0d9ff90a5422cc7509258aaaba1e7481df4d332a Bisecting: 163 revisions left to test after this (roughly 8 steps) [2beb1b31a12b57e19cd5c82ea6d54e56520605e8] Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf determine whether the revision contains the guilty commit revision 70f5376dbdefa675adec0800e9f21f20a0dc0cbd crashed and is reachable testing commit 2beb1b31a12b57e19cd5c82ea6d54e56520605e8 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 73c7f6058c1d6ce58d09d58c3c34b3af2c270bab5dc6ec9b6a6791151c24287b all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good 2beb1b31a12b57e19cd5c82ea6d54e56520605e8 Bisecting: 81 revisions left to test after this (roughly 6 steps) [50d05c7c76c96b90462f24debacca971d2e86713] Merge tag 'landlock-7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit 50d05c7c76c96b90462f24debacca971d2e86713 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: a8485a60bbe61d9f61b536981c1fae1818d3d444c6256ad633f71730750b49ef all runs: OK false negative chance: 0.000 # git bisect bad 50d05c7c76c96b90462f24debacca971d2e86713 Bisecting: 40 revisions left to test after this (roughly 5 steps) [893e11787f78e43b534e252249ac3fff4d1333f8] Merge tag 'x86_urgent_for_7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit 893e11787f78e43b534e252249ac3fff4d1333f8 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 90e2df19041a6e8200ff1494ab96aaab52358882ab665b271a21ad48f08d19b9 all runs: OK false negative chance: 0.000 # git bisect bad 893e11787f78e43b534e252249ac3fff4d1333f8 Bisecting: 20 revisions left to test after this (roughly 4 steps) [28924df2a08f440c73991b83028032c901de2ae4] Merge tag 'perf-tools-fixes-for-v7.3-2026-09-07' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools determine whether the revision contains the guilty commit revision 0d9ff90a5422cc7509258aaaba1e7481df4d332a crashed and is reachable testing commit 28924df2a08f440c73991b83028032c901de2ae4 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 64215db29e68eaa100d63a099ea26b4b5911aae28667a350e139d491d3fd8872 all runs: OK false negative chance: 0.000 # git bisect bad 28924df2a08f440c73991b83028032c901de2ae4 Bisecting: 9 revisions left to test after this (roughly 3 steps) [c843fd3c73c94cb90b01c6bfe8d83796e652864d] ring-buffer: Prevent truncation of nr_pages / nr_subbufs determine whether the revision contains the guilty commit revision 70f5376dbdefa675adec0800e9f21f20a0dc0cbd crashed and is reachable testing commit c843fd3c73c94cb90b01c6bfe8d83796e652864d gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: d6bf14f3825535f5fb58f9eed65e395cdec25c7e7da2b5455b4e44f628be3286 all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good c843fd3c73c94cb90b01c6bfe8d83796e652864d Bisecting: 4 revisions left to test after this (roughly 2 steps) [a7c1290eef60711c10289c056ad32ed1f2b47b12] configfs: pin the symlink target's dirent instead of chasing ->ci_dentry determine whether the revision contains the guilty commit revision 2beb1b31a12b57e19cd5c82ea6d54e56520605e8 crashed and is reachable testing commit a7c1290eef60711c10289c056ad32ed1f2b47b12 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: db6ac804e7471fa2939f0dd3159a3e8e36a06d3e5fa8eb658b2ebaec502fae60 all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good a7c1290eef60711c10289c056ad32ed1f2b47b12 Bisecting: 2 revisions left to test after this (roughly 1 step) [aadea57f532882d8bab444646863c7ef8a778ff1] perf powerpc-vpadtl: Fix raw_size of DTL samples determine whether the revision contains the guilty commit revision 2f1baf1fc8929e6c48370be543ad028ac7ad4131 crashed and is reachable testing commit aadea57f532882d8bab444646863c7ef8a778ff1 gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 9916af112d42992dd39da1413280137285d1cdfbdc53e0510223160df541ea2e all runs: crashed: WARNING: refcount bug in config_item_get representative crash: WARNING: refcount bug in config_item_get, types: [REFCOUNT_WARNING] # git bisect good aadea57f532882d8bab444646863c7ef8a778ff1 Bisecting: 0 revisions left to test after this (roughly 1 step) [c297ed90fbba72d32b7759aae362b36d15b2db1f] Merge tag 'configfs-7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/leitao/linux determine whether the revision contains the guilty commit revision c843fd3c73c94cb90b01c6bfe8d83796e652864d crashed and is reachable testing commit c297ed90fbba72d32b7759aae362b36d15b2db1f gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 52b0c81ef7eb42552b1d304816bfaffa1adaa6add8b21c16564f4f1235ccbb61 all runs: OK false negative chance: 0.000 # git bisect bad c297ed90fbba72d32b7759aae362b36d15b2db1f Bisecting: 0 revisions left to test after this (roughly 0 steps) [f06c2d26d1999d37e93299db0ecead04ca7d0b9f] configfs: unhash the dentry before dropping the item in rmdir determine whether the revision contains the guilty commit revision 70f5376dbdefa675adec0800e9f21f20a0dc0cbd crashed and is reachable testing commit f06c2d26d1999d37e93299db0ecead04ca7d0b9f gcc compiler: Debian clang version 22.1.8 (1~deb13u4), Debian LLD 22.1.8 kernel signature: 13cfe882c419768c4e82c0f0f3f08ea88412e20ba3415113741e63a9274e5f08 all runs: OK false negative chance: 0.000 # git bisect bad f06c2d26d1999d37e93299db0ecead04ca7d0b9f f06c2d26d1999d37e93299db0ecead04ca7d0b9f is the first bad commit commit f06c2d26d1999d37e93299db0ecead04ca7d0b9f Author: Vasileios Almpanis Date: Thu Jul 30 11:30:25 2026 +0200 configfs: unhash the dentry before dropping the item in rmdir configfs_get_config_item() treats a hashed dentry as proof that sd->s_element is a live config_item. configfs_rmdir() breaks that: simple_rmdir() leaves the dentry hashed, the last reference to the item is dropped right after, and the dentry is only unhashed by d_delete() once ->rmdir() has returned. configfs_symlink() resolves its target holding no lock on it, so get_target() can land in that window: BUG: KASAN: slab-use-after-free in config_item_get+0x26/0x90 get_target fs/configfs/symlink.c:128 [inline] configfs_symlink+0x4ab/0x1030 fs/configfs/symlink.c:185 Unhash in configfs_remove_dir(), while the item is still guaranteed to be there. A reference obtained just before that stays harmless, as create_link() rechecks CONFIGFS_USET_DROPPING, already set by configfs_detach_prep(). Both configfs_unregister_subsystem() paths d_drop() after detaching, so this only makes rmdir match them. Reported-by: syzbot+6b16e3d085833cbf3e25@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6b16e3d085833cbf3e25 Fixes: 7063fbf22611 ("[PATCH] configfs: User-driven configuration filesystem") Cc: stable@vger.kernel.org Signed-off-by: Vasileios Almpanis Tested-by: Breno Leitao Reviewed-by: Breno Leitao Link: https://patch.msgid.link/20260730093435.195441-3-vasilisalmpanis@gmail.com Signed-off-by: Breno Leitao fs/configfs/dir.c | 9 +++++++++ 1 file changed, 9 insertions(+) accumulated error probability: 0.00 culprit signature: 13cfe882c419768c4e82c0f0f3f08ea88412e20ba3415113741e63a9274e5f08 parent signature: db6ac804e7471fa2939f0dd3159a3e8e36a06d3e5fa8eb658b2ebaec502fae60 revisions tested: 23, total time: 8h17m54.367648827s (build: 4h2m3.49085237s, test: 3h18m20.176607909s) first good commit: f06c2d26d1999d37e93299db0ecead04ca7d0b9f configfs: unhash the dentry before dropping the item in rmdir recipients (to): ["leitao@debian.org" "vasilisalmpanis@gmail.com"] recipients (cc): []