The mac80211 subsystem in the Linux kernel before 5.12.13, when a device supporting only 5 GHz is used, allows attackers to cause a denial of service (NULL pointer dereference in the radiotap parser) by injecting a frame with 802.11a rates.

NVIDIA GPU Display Driver for Windows and Linux contains a vulnerability in the kernel mode layer, where a NULL-pointer dereference may lead to denial of service.

NVIDIA GPU Driver for Windows and Linux contains a vulnerability in the kernel mode layer, where an unprivileged regular user can cause a NULL-pointer dereference, which may lead to denial of service.

In the Linux kernel, the following vulnerability has been resolved: staging: gpib: Fix Oops after disconnect in agilent usb If the agilent usb dongle is disconnected subsequent calls to the driver cause a NULL dereference Oops as the bus_interface is set to NULL on disconnect. This problem was introduced by setting usb_dev from the bus_interface for dev_xxx messages. Previously bus_interface was checked for NULL only in the functions directly calling usb_fill_bulk_urb or usb_control_msg. Check for valid bus_interface on all interface entry points and return -ENODEV if it is NULL.

In the Linux kernel, the following vulnerability has been resolved: usb: renesas_usbhs: Flush the notify_hotplug_work When performing continuous unbind/bind operations on the USB drivers available on the Renesas RZ/G2L SoC, a kernel crash with the message "Unable to handle kernel NULL pointer dereference at virtual address" may occur. This issue points to the usbhsc_notify_hotplug() function. Flush the delayed work to avoid its execution when driver resources are unavailable.

In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix kernel crash when 1588 is sent on HIP08 devices Currently, HIP08 devices does not register the ptp devices, so the hdev->ptp is NULL. But the tx process would still try to set hardware time stamp info with SKBTX_HW_TSTAMP flag and cause a kernel crash. [ 128.087798] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018 ... [ 128.280251] pc : hclge_ptp_set_tx_info+0x2c/0x140 [hclge] [ 128.286600] lr : hclge_ptp_set_tx_info+0x20/0x140 [hclge] [ 128.292938] sp : ffff800059b93140 [ 128.297200] x29: ffff800059b93140 x28: 0000000000003280 [ 128.303455] x27: ffff800020d48280 x26: ffff0cb9dc814080 [ 128.309715] x25: ffff0cb9cde93fa0 x24: 0000000000000001 [ 128.315969] x23: 0000000000000000 x22: 0000000000000194 [ 128.322219] x21: ffff0cd94f986000 x20: 0000000000000000 [ 128.328462] x19: ffff0cb9d2a166c0 x18: 0000000000000000 [ 128.334698] x17: 0000000000000000 x16: ffffcf1fc523ed24 [ 128.340934] x15: 0000ffffd530a518 x14: 0000000000000000 [ 128.347162] x13: ffff0cd6bdb31310 x12: 0000000000000368 [ 128.353388] x11: ffff0cb9cfbc7070 x10: ffff2cf55dd11e02 [ 128.359606] x9 : ffffcf1f85a212b4 x8 : ffff0cd7cf27dab0 [ 128.365831] x7 : 0000000000000a20 x6 : ffff0cd7cf27d000 [ 128.372040] x5 : 0000000000000000 x4 : 000000000000ffff [ 128.378243] x3 : 0000000000000400 x2 : ffffcf1f85a21294 [ 128.384437] x1 : ffff0cb9db520080 x0 : ffff0cb9db500080 [ 128.390626] Call trace: [ 128.393964] hclge_ptp_set_tx_info+0x2c/0x140 [hclge] [ 128.399893] hns3_nic_net_xmit+0x39c/0x4c4 [hns3] [ 128.405468] xmit_one.constprop.0+0xc4/0x200 [ 128.410600] dev_hard_start_xmit+0x54/0xf0 [ 128.415556] sch_direct_xmit+0xe8/0x634 [ 128.420246] __dev_queue_xmit+0x224/0xc70 [ 128.425101] dev_queue_xmit+0x1c/0x40 [ 128.429608] ovs_vport_send+0xac/0x1a0 [openvswitch] [ 128.435409] do_output+0x60/0x17c [openvswitch] [ 128.440770] do_execute_actions+0x898/0x8c4 [openvswitch] [ 128.446993] ovs_execute_actions+0x64/0xf0 [openvswitch] [ 128.453129] ovs_dp_process_packet+0xa0/0x224 [openvswitch] [ 128.459530] ovs_vport_receive+0x7c/0xfc [openvswitch] [ 128.465497] internal_dev_xmit+0x34/0xb0 [openvswitch] [ 128.471460] xmit_one.constprop.0+0xc4/0x200 [ 128.476561] dev_hard_start_xmit+0x54/0xf0 [ 128.481489] __dev_queue_xmit+0x968/0xc70 [ 128.486330] dev_queue_xmit+0x1c/0x40 [ 128.490856] ip_finish_output2+0x250/0x570 [ 128.495810] __ip_finish_output+0x170/0x1e0 [ 128.500832] ip_finish_output+0x3c/0xf0 [ 128.505504] ip_output+0xbc/0x160 [ 128.509654] ip_send_skb+0x58/0xd4 [ 128.513892] udp_send_skb+0x12c/0x354 [ 128.518387] udp_sendmsg+0x7a8/0x9c0 [ 128.522793] inet_sendmsg+0x4c/0x8c [ 128.527116] __sock_sendmsg+0x48/0x80 [ 128.531609] __sys_sendto+0x124/0x164 [ 128.536099] __arm64_sys_sendto+0x30/0x5c [ 128.540935] invoke_syscall+0x50/0x130 [ 128.545508] el0_svc_common.constprop.0+0x10c/0x124 [ 128.551205] do_el0_svc+0x34/0xdc [ 128.555347] el0_svc+0x20/0x30 [ 128.559227] el0_sync_handler+0xb8/0xc0 [ 128.563883] el0_sync+0x160/0x180

A NULL pointer dereference flaw was found in the az6027 driver in drivers/media/usb/dev-usb/az6027.c in the Linux Kernel. The message from user space is not checked properly before transferring into the device. This flaw allows a local user to crash the system or potentially cause a denial of service.

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Fix potential null dereference on pointer status There are calls to idxd_cmd_exec that pass a null status pointer however a recent commit has added an assignment to *status that can end up with a null pointer dereference. The function expects a null status pointer sometimes as there is a later assignment to *status where status is first null checked. Fix the issue by null checking status before making the assignment. Addresses-Coverity: ("Explicit null dereferenced")

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: check dpu_plane_atomic_print_state() for valid sspp Similar to the r_pipe sspp protect, add a check to protect the pipe state prints to avoid NULL ptr dereference for cases when the state is dumped without a corresponding atomic_check() where the pipe->sspp is assigned. Patchwork: https://patchwork.freedesktop.org/patch/628404/

In the Linux kernel before 6.1.2, kernel/module/decompress.c misinterprets the module_get_next_page return value (expects it to be NULL in the error case, whereas it is actually an error pointer).

In the Linux kernel before 5.15.13, drivers/net/ethernet/mellanox/mlx5/core/steering/dr_domain.c misinterprets the mlx5_get_uars_page return value (expects it to be NULL in the error case, whereas it is actually an error pointer).

In the Linux kernel before 5.19, drivers/gpu/drm/arm/malidp_planes.c misinterprets the get_sg_table return value (expects it to be NULL in the error case, whereas it is actually an error pointer).

In the Linux kernel before 5.16.3, drivers/scsi/ufs/ufs-mediatek.c misinterprets the regulator_get return value (expects it to be NULL in the error case, whereas it is actually an error pointer).

In the Linux kernel, the following vulnerability has been resolved: platform/x86: int3472: Check for adev == NULL Not all devices have an ACPI companion fwnode, so adev might be NULL. This can e.g. (theoretically) happen when a user manually binds one of the int3472 drivers to another i2c/platform device through sysfs. Add a check for adev not being set and return -ENODEV in that case to avoid a possible NULL pointer deref in skl_int3472_get_acpi_buffer().

In the Linux kernel, the following vulnerability has been resolved: scsi: hisi_sas: Create all dump files during debugfs initialization For the current debugfs of hisi_sas, after user triggers dump, the driver allocate memory space to save the register information and create debugfs files to display the saved information. In this process, the debugfs files created after each dump. Therefore, when the dump is triggered while the driver is unbind, the following hang occurs: [67840.853907] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0 [67840.862947] Mem abort info: [67840.865855] ESR = 0x0000000096000004 [67840.869713] EC = 0x25: DABT (current EL), IL = 32 bits [67840.875125] SET = 0, FnV = 0 [67840.878291] EA = 0, S1PTW = 0 [67840.881545] FSC = 0x04: level 0 translation fault [67840.886528] Data abort info: [67840.889524] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [67840.895117] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [67840.900284] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [67840.905709] user pgtable: 4k pages, 48-bit VAs, pgdp=0000002803a1f000 [67840.912263] [00000000000000a0] pgd=0000000000000000, p4d=0000000000000000 [67840.919177] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [67840.996435] pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [67841.003628] pc : down_write+0x30/0x98 [67841.007546] lr : start_creating.part.0+0x60/0x198 [67841.012495] sp : ffff8000b979ba20 [67841.016046] x29: ffff8000b979ba20 x28: 0000000000000010 x27: 0000000000024b40 [67841.023412] x26: 0000000000000012 x25: ffff20202b355ae8 x24: ffff20202b35a8c8 [67841.030779] x23: ffffa36877928208 x22: ffffa368b4972240 x21: ffff8000b979bb18 [67841.038147] x20: ffff00281dc1e3c0 x19: fffffffffffffffe x18: 0000000000000020 [67841.045515] x17: 0000000000000000 x16: ffffa368b128a530 x15: ffffffffffffffff [67841.052888] x14: ffff8000b979bc18 x13: ffffffffffffffff x12: ffff8000b979bb18 [67841.060263] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffa368b1289b18 [67841.067640] x8 : 0000000000000012 x7 : 0000000000000000 x6 : 00000000000003a9 [67841.075014] x5 : 0000000000000000 x4 : ffff002818c5cb00 x3 : 0000000000000001 [67841.082388] x2 : 0000000000000000 x1 : ffff002818c5cb00 x0 : 00000000000000a0 [67841.089759] Call trace: [67841.092456] down_write+0x30/0x98 [67841.096017] start_creating.part.0+0x60/0x198 [67841.100613] debugfs_create_dir+0x48/0x1f8 [67841.104950] debugfs_create_files_v3_hw+0x88/0x348 [hisi_sas_v3_hw] [67841.111447] debugfs_snapshot_regs_v3_hw+0x708/0x798 [hisi_sas_v3_hw] [67841.118111] debugfs_trigger_dump_v3_hw_write+0x9c/0x120 [hisi_sas_v3_hw] [67841.125115] full_proxy_write+0x68/0xc8 [67841.129175] vfs_write+0xd8/0x3f0 [67841.132708] ksys_write+0x70/0x108 [67841.136317] __arm64_sys_write+0x24/0x38 [67841.140440] invoke_syscall+0x50/0x128 [67841.144385] el0_svc_common.constprop.0+0xc8/0xf0 [67841.149273] do_el0_svc+0x24/0x38 [67841.152773] el0_svc+0x38/0xd8 [67841.156009] el0t_64_sync_handler+0xc0/0xc8 [67841.160361] el0t_64_sync+0x1a4/0x1a8 [67841.164189] Code: b9000882 d2800002 d2800023 f9800011 (c85ffc05) [67841.170443] ---[ end trace 0000000000000000 ]--- To fix this issue, create all directories and files during debugfs initialization. In this way, the driver only needs to allocate memory space to save information each time the user triggers dumping.

In the Linux kernel, the following vulnerability has been resolved: net: enetc: Do not configure preemptible TCs if SIs do not support Both ENETC PF and VF drivers share enetc_setup_tc_mqprio() to configure MQPRIO. And enetc_setup_tc_mqprio() calls enetc_change_preemptible_tcs() to configure preemptible TCs. However, only PF is able to configure preemptible TCs. Because only PF has related registers, while VF does not have these registers. So for VF, its hw->port pointer is NULL. Therefore, VF will access an invalid pointer when accessing a non-existent register, which will cause a crash issue. The simplified log is as follows. root@ls1028ardb:~# tc qdisc add dev eno0vf0 parent root handle 100: \ mqprio num_tc 4 map 0 0 1 1 2 2 3 3 queues 1@0 1@1 1@2 1@3 hw 1 [ 187.290775] Unable to handle kernel paging request at virtual address 0000000000001f00 [ 187.424831] pc : enetc_mm_commit_preemptible_tcs+0x1c4/0x400 [ 187.430518] lr : enetc_mm_commit_preemptible_tcs+0x30c/0x400 [ 187.511140] Call trace: [ 187.513588] enetc_mm_commit_preemptible_tcs+0x1c4/0x400 [ 187.518918] enetc_setup_tc_mqprio+0x180/0x214 [ 187.523374] enetc_vf_setup_tc+0x1c/0x30 [ 187.527306] mqprio_enable_offload+0x144/0x178 [ 187.531766] mqprio_init+0x3ec/0x668 [ 187.535351] qdisc_create+0x15c/0x488 [ 187.539023] tc_modify_qdisc+0x398/0x73c [ 187.542958] rtnetlink_rcv_msg+0x128/0x378 [ 187.547064] netlink_rcv_skb+0x60/0x130 [ 187.550910] rtnetlink_rcv+0x18/0x24 [ 187.554492] netlink_unicast+0x300/0x36c [ 187.558425] netlink_sendmsg+0x1a8/0x420 [ 187.606759] ---[ end trace 0000000000000000 ]--- In addition, some PFs also do not support configuring preemptible TCs, such as eno1 and eno3 on LS1028A. It won't crash like it does for VFs, but we should prevent these PFs from accessing these unimplemented registers.

In the Linux kernel, the following vulnerability has been resolved: leds: class: Protect brightness_show() with led_cdev->led_access mutex There is NULL pointer issue observed if from Process A where hid device being added which results in adding a led_cdev addition and later a another call to access of led_cdev attribute from Process B can result in NULL pointer issue. Use mutex led_cdev->led_access to protect access to led->cdev and its attribute inside brightness_show() and max_brightness_show() and also update the comment for mutex that it should be used to protect the led class device fields. Process A Process B kthread+0x114 worker_thread+0x244 process_scheduled_works+0x248 uhid_device_add_worker+0x24 hid_add_device+0x120 device_add+0x268 bus_probe_device+0x94 device_initial_probe+0x14 __device_attach+0xfc bus_for_each_drv+0x10c __device_attach_driver+0x14c driver_probe_device+0x3c __driver_probe_device+0xa0 really_probe+0x190 hid_device_probe+0x130 ps_probe+0x990 ps_led_register+0x94 devm_led_classdev_register_ext+0x58 led_classdev_register_ext+0x1f8 device_create_with_groups+0x48 device_create_groups_vargs+0xc8 device_add+0x244 kobject_uevent+0x14 kobject_uevent_env[jt]+0x224 mutex_unlock[jt]+0xc4 __mutex_unlock_slowpath+0xd4 wake_up_q+0x70 try_to_wake_up[jt]+0x48c preempt_schedule_common+0x28 __schedule+0x628 __switch_to+0x174 el0t_64_sync+0x1a8/0x1ac el0t_64_sync_handler+0x68/0xbc el0_svc+0x38/0x68 do_el0_svc+0x1c/0x28 el0_svc_common+0x80/0xe0 invoke_syscall+0x58/0x114 __arm64_sys_read+0x1c/0x2c ksys_read+0x78/0xe8 vfs_read+0x1e0/0x2c8 kernfs_fop_read_iter+0x68/0x1b4 seq_read_iter+0x158/0x4ec kernfs_seq_show+0x44/0x54 sysfs_kf_seq_show+0xb4/0x130 dev_attr_show+0x38/0x74 brightness_show+0x20/0x4c dualshock4_led_get_brightness+0xc/0x74 [ 3313.874295][ T4013] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060 [ 3313.874301][ T4013] Mem abort info: [ 3313.874303][ T4013] ESR = 0x0000000096000006 [ 3313.874305][ T4013] EC = 0x25: DABT (current EL), IL = 32 bits [ 3313.874307][ T4013] SET = 0, FnV = 0 [ 3313.874309][ T4013] EA = 0, S1PTW = 0 [ 3313.874311][ T4013] FSC = 0x06: level 2 translation fault [ 3313.874313][ T4013] Data abort info: [ 3313.874314][ T4013] ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 [ 3313.874316][ T4013] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 3313.874318][ T4013] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 3313.874320][ T4013] user pgtable: 4k pages, 39-bit VAs, pgdp=00000008f2b0a000 .. [ 3313.874332][ T4013] Dumping ftrace buffer: [ 3313.874334][ T4013] (ftrace buffer empty) .. .. [ dd3313.874639][ T4013] CPU: 6 PID: 4013 Comm: InputReader [ 3313.874648][ T4013] pc : dualshock4_led_get_brightness+0xc/0x74 [ 3313.874653][ T4013] lr : led_update_brightness+0x38/0x60 [ 3313.874656][ T4013] sp : ffffffc0b910bbd0 .. .. [ 3313.874685][ T4013] Call trace: [ 3313.874687][ T4013] dualshock4_led_get_brightness+0xc/0x74 [ 3313.874690][ T4013] brightness_show+0x20/0x4c [ 3313.874692][ T4013] dev_attr_show+0x38/0x74 [ 3313.874696][ T4013] sysfs_kf_seq_show+0xb4/0x130 [ 3313.874700][ T4013] kernfs_seq_show+0x44/0x54 [ 3313.874703][ T4013] seq_read_iter+0x158/0x4ec [ 3313.874705][ T4013] kernfs_fop_read_iter+0x68/0x1b4 [ 3313.874708][ T4013] vfs_read+0x1e0/0x2c8 [ 3313.874711][ T4013] ksys_read+0x78/0xe8 [ 3313.874714][ T4013] __arm64_sys_read+0x1c/0x2c [ 3313.874718][ T4013] invoke_syscall+0x58/0x114 [ 3313.874721][ T4013] el0_svc_common+0x80/0xe0 [ 3313.874724][ T4013] do_el0_svc+0x1c/0x28 [ 3313.874727][ T4013] el0_svc+0x38/0x68 [ 3313.874730][ T4013] el0t_64_sync_handler+0x68/0xbc [ 3313.874732][ T4013] el0t_64_sync+0x1a8/0x1ac

In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix null ptr access msm_ioctl_gem_submit() Fix the below null pointer dereference in msm_ioctl_gem_submit(): 26545.260705: Call trace: 26545.263223: kref_put+0x1c/0x60 26545.266452: msm_ioctl_gem_submit+0x254/0x744 26545.270937: drm_ioctl_kernel+0xa8/0x124 26545.274976: drm_ioctl+0x21c/0x33c 26545.278478: drm_compat_ioctl+0xdc/0xf0 26545.282428: __arm64_compat_sys_ioctl+0xc8/0x100 26545.287169: el0_svc_common+0xf8/0x250 26545.291025: do_el0_svc_compat+0x28/0x54 26545.295066: el0_svc_compat+0x10/0x1c 26545.298838: el0_sync_compat_handler+0xa8/0xcc 26545.303403: el0_sync_compat+0x188/0x1c0 26545.307445: Code: d503201f d503201f 52800028 4b0803e8 (b8680008) 26545.318799: Kernel panic - not syncing: Oops: Fatal exception

In the Linux kernel, the following vulnerability has been resolved: scsi: core: Fix bad pointer dereference when ehandler kthread is invalid Commit 66a834d09293 ("scsi: core: Fix error handling of scsi_host_alloc()") changed the allocation logic to call put_device() to perform host cleanup with the assumption that IDA removal and stopping the kthread would properly be performed in scsi_host_dev_release(). However, in the unlikely case that the error handler thread fails to spawn, shost->ehandler is set to ERR_PTR(-ENOMEM). The error handler cleanup code in scsi_host_dev_release() will call kthread_stop() if shost->ehandler != NULL which will always be the case whether the kthread was successfully spawned or not. In the case that it failed to spawn this has the nasty side effect of trying to dereference an invalid pointer when kthread_stop() is called. The following splat provides an example of this behavior in the wild: scsi host11: error handler thread failed to spawn, error = -4 Kernel attempted to read user page (10c) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x0000010c Faulting instruction address: 0xc00000000818e9a8 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: ibmvscsi(+) scsi_transport_srp dm_multipath dm_mirror dm_region hash dm_log dm_mod fuse overlay squashfs loop CPU: 12 PID: 274 Comm: systemd-udevd Not tainted 5.13.0-rc7 #1 NIP: c00000000818e9a8 LR: c0000000089846e8 CTR: 0000000000007ee8 REGS: c000000037d12ea0 TRAP: 0300 Not tainted (5.13.0-rc7) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 28228228 XER: 20040001 CFAR: c0000000089846e4 DAR: 000000000000010c DSISR: 40000000 IRQMASK: 0 GPR00: c0000000089846e8 c000000037d13140 c000000009cc1100 fffffffffffffffc GPR04: 0000000000000001 0000000000000000 0000000000000000 c000000037dc0000 GPR08: 0000000000000000 c000000037dc0000 0000000000000001 00000000fffff7ff GPR12: 0000000000008000 c00000000a049000 c000000037d13d00 000000011134d5a0 GPR16: 0000000000001740 c0080000190d0000 c0080000190d1740 c000000009129288 GPR20: c000000037d13bc0 0000000000000001 c000000037d13bc0 c0080000190b7898 GPR24: c0080000190b7708 0000000000000000 c000000033bb2c48 0000000000000000 GPR28: c000000046b28280 0000000000000000 000000000000010c fffffffffffffffc NIP [c00000000818e9a8] kthread_stop+0x38/0x230 LR [c0000000089846e8] scsi_host_dev_release+0x98/0x160 Call Trace: [c000000033bb2c48] 0xc000000033bb2c48 (unreliable) [c0000000089846e8] scsi_host_dev_release+0x98/0x160 [c00000000891e960] device_release+0x60/0x100 [c0000000087e55c4] kobject_release+0x84/0x210 [c00000000891ec78] put_device+0x28/0x40 [c000000008984ea4] scsi_host_alloc+0x314/0x430 [c0080000190b38bc] ibmvscsi_probe+0x54/0xad0 [ibmvscsi] [c000000008110104] vio_bus_probe+0xa4/0x4b0 [c00000000892a860] really_probe+0x140/0x680 [c00000000892aefc] driver_probe_device+0x15c/0x200 [c00000000892b63c] device_driver_attach+0xcc/0xe0 [c00000000892b740] __driver_attach+0xf0/0x200 [c000000008926f28] bus_for_each_dev+0xa8/0x130 [c000000008929ce4] driver_attach+0x34/0x50 [c000000008928fc0] bus_add_driver+0x1b0/0x300 [c00000000892c798] driver_register+0x98/0x1a0 [c00000000810eb60] __vio_register_driver+0x80/0xe0 [c0080000190b4a30] ibmvscsi_module_init+0x9c/0xdc [ibmvscsi] [c0000000080121d0] do_one_initcall+0x60/0x2d0 [c000000008261abc] do_init_module+0x7c/0x320 [c000000008265700] load_module+0x2350/0x25b0 [c000000008265cb4] __do_sys_finit_module+0xd4/0x160 [c000000008031110] system_call_exception+0x150/0x2d0 [c00000000800d35c] system_call_common+0xec/0x278 Fix this be nulling shost->ehandler when the kthread fails to spawn.

In the Linux kernel, the following vulnerability has been resolved: atm: Fix NULL pointer dereference When MPOA_cache_impos_rcvd() receives the msg, it can trigger Null Pointer Dereference Vulnerability if both entry and holding_time are NULL. Because there is only for the situation where entry is NULL and holding_time exists, it can be passed when both entry and holding_time are NULL. If these are NULL, the entry will be passd to eg_cache_put() as parameter and it is referenced by entry->use code in it. kasan log: [ 3.316691] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006:I [ 3.317568] KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] [ 3.318188] CPU: 3 UID: 0 PID: 79 Comm: ex Not tainted 6.14.0-rc2 #102 [ 3.318601] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 [ 3.319298] RIP: 0010:eg_cache_remove_entry+0xa5/0x470 [ 3.319677] Code: c1 f7 6e fd 48 c7 c7 00 7e 38 b2 e8 95 64 54 fd 48 c7 c7 40 7e 38 b2 48 89 ee e80 [ 3.321220] RSP: 0018:ffff88800583f8a8 EFLAGS: 00010006 [ 3.321596] RAX: 0000000000000006 RBX: ffff888005989000 RCX: ffffffffaecc2d8e [ 3.322112] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000030 [ 3.322643] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff6558b88 [ 3.323181] R10: 0000000000000003 R11: 203a207972746e65 R12: 1ffff11000b07f15 [ 3.323707] R13: dffffc0000000000 R14: ffff888005989000 R15: ffff888005989068 [ 3.324185] FS: 000000001b6313c0(0000) GS:ffff88806d380000(0000) knlGS:0000000000000000 [ 3.325042] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3.325545] CR2: 00000000004b4b40 CR3: 000000000248e000 CR4: 00000000000006f0 [ 3.326430] Call Trace: [ 3.326725] <TASK> [ 3.326927] ? die_addr+0x3c/0xa0 [ 3.327330] ? exc_general_protection+0x161/0x2a0 [ 3.327662] ? asm_exc_general_protection+0x26/0x30 [ 3.328214] ? vprintk_emit+0x15e/0x420 [ 3.328543] ? eg_cache_remove_entry+0xa5/0x470 [ 3.328910] ? eg_cache_remove_entry+0x9a/0x470 [ 3.329294] ? __pfx_eg_cache_remove_entry+0x10/0x10 [ 3.329664] ? console_unlock+0x107/0x1d0 [ 3.329946] ? __pfx_console_unlock+0x10/0x10 [ 3.330283] ? do_syscall_64+0xa6/0x1a0 [ 3.330584] ? entry_SYSCALL_64_after_hwframe+0x47/0x7f [ 3.331090] ? __pfx_prb_read_valid+0x10/0x10 [ 3.331395] ? down_trylock+0x52/0x80 [ 3.331703] ? vprintk_emit+0x15e/0x420 [ 3.331986] ? __pfx_vprintk_emit+0x10/0x10 [ 3.332279] ? down_trylock+0x52/0x80 [ 3.332527] ? _printk+0xbf/0x100 [ 3.332762] ? __pfx__printk+0x10/0x10 [ 3.333007] ? _raw_write_lock_irq+0x81/0xe0 [ 3.333284] ? __pfx__raw_write_lock_irq+0x10/0x10 [ 3.333614] msg_from_mpoad+0x1185/0x2750 [ 3.333893] ? __build_skb_around+0x27b/0x3a0 [ 3.334183] ? __pfx_msg_from_mpoad+0x10/0x10 [ 3.334501] ? __alloc_skb+0x1c0/0x310 [ 3.334809] ? __pfx___alloc_skb+0x10/0x10 [ 3.335283] ? _raw_spin_lock+0xe0/0xe0 [ 3.335632] ? finish_wait+0x8d/0x1e0 [ 3.335975] vcc_sendmsg+0x684/0xba0 [ 3.336250] ? __pfx_vcc_sendmsg+0x10/0x10 [ 3.336587] ? __pfx_autoremove_wake_function+0x10/0x10 [ 3.337056] ? fdget+0x176/0x3e0 [ 3.337348] __sys_sendto+0x4a2/0x510 [ 3.337663] ? __pfx___sys_sendto+0x10/0x10 [ 3.337969] ? ioctl_has_perm.constprop.0.isra.0+0x284/0x400 [ 3.338364] ? sock_ioctl+0x1bb/0x5a0 [ 3.338653] ? __rseq_handle_notify_resume+0x825/0xd20 [ 3.339017] ? __pfx_sock_ioctl+0x10/0x10 [ 3.339316] ? __pfx___rseq_handle_notify_resume+0x10/0x10 [ 3.339727] ? selinux_file_ioctl+0xa4/0x260 [ 3.340166] __x64_sys_sendto+0xe0/0x1c0 [ 3.340526] ? syscall_exit_to_user_mode+0x123/0x140 [ 3.340898] do_syscall_64+0xa6/0x1a0 [ 3.341170] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 3.341533] RIP: 0033:0x44a380 [ 3.341757] Code: 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c00 [ ---truncated---

A NULL pointer dereference flaw was found in the Linux kernel’s IEEE 802.15.4 wireless networking subsystem in the way the user closes the LR-WPAN connection. This flaw allows a local user to crash the system. The highest threat from this vulnerability is to system availability.

In the Linux kernel, the following vulnerability has been resolved: can: mcp251xfd: mcp251xfd_probe(): fix an error pointer dereference in probe When we converted this code to use dev_err_probe() we accidentally removed a return. It means that if devm_clk_get() it will lead to an Oops when we call clk_get_rate() on the next line.

In the Linux kernel, the following vulnerability has been resolved: sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb We should always check if skb_header_pointer's return is NULL before using it, otherwise it may cause null-ptr-deref, as syzbot reported: KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:sctp_rcv_ootb net/sctp/input.c:705 [inline] RIP: 0010:sctp_rcv+0x1d84/0x3220 net/sctp/input.c:196 Call Trace: <IRQ> sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109 ip6_protocol_deliver_rcu+0x2e9/0x1ca0 net/ipv6/ip6_input.c:422 ip6_input_finish+0x62/0x170 net/ipv6/ip6_input.c:463 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:472 dst_input include/net/dst.h:460 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ipv6_rcv+0x28c/0x3c0 net/ipv6/ip6_input.c:297

In the Linux kernel, the following vulnerability has been resolved: HID: amd_sfh: Fix potential NULL pointer dereference devm_add_action_or_reset() can suddenly invoke amd_mp2_pci_remove() at registration that will cause NULL pointer dereference since corresponding data is not initialized yet. The patch moves initialization of data before devm_add_action_or_reset(). Found by Linux Driver Verification project (linuxtesting.org). [jkosina@suse.cz: rebase]

fs/btrfs/volumes.c in the Linux kernel before 5.1 allows a btrfs_verify_dev_extents NULL pointer dereference via a crafted btrfs image because fs_devices->devices is mishandled within find_device, aka CID-09ba3bc9dd15.

In the Linux kernel, the following vulnerability has been resolved: mm: fix NULL pointer dereference in alloc_pages_bulk_noprof We triggered a NULL pointer dereference for ac.preferred_zoneref->zone in alloc_pages_bulk_noprof() when the task is migrated between cpusets. When cpuset is enabled, in prepare_alloc_pages(), ac->nodemask may be &current->mems_allowed. when first_zones_zonelist() is called to find preferred_zoneref, the ac->nodemask may be modified concurrently if the task is migrated between different cpusets. Assuming we have 2 NUMA Node, when traversing Node1 in ac->zonelist, the nodemask is 2, and when traversing Node2 in ac->zonelist, the nodemask is 1. As a result, the ac->preferred_zoneref points to NULL zone. In alloc_pages_bulk_noprof(), for_each_zone_zonelist_nodemask() finds a allowable zone and calls zonelist_node_idx(ac.preferred_zoneref), leading to NULL pointer dereference. __alloc_pages_noprof() fixes this issue by checking NULL pointer in commit ea57485af8f4 ("mm, page_alloc: fix check for NULL preferred_zone") and commit df76cee6bbeb ("mm, page_alloc: remove redundant checks from alloc fastpath"). To fix it, check NULL pointer for preferred_zoneref->zone.

In nf_tables_updtable, if nf_tables_table_enable returns an error, nft_trans_destroy is called to free the transaction object. nft_trans_destroy() calls list_del(), but the transaction was never placed on a list -- the list head is all zeroes, this results in a NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix NULL pointer dereference in svm_migrate_to_ram() ./drivers/gpu/drm/amd/amdkfd/kfd_migrate.c:985:58-62: ERROR: p is NULL but dereferenced.

A NULL pointer dereference flaw was found in the UNIX protocol in net/unix/diag.c In unix_diag_get_exact in the Linux Kernel. The newly allocated skb does not have sk, leading to a NULL pointer. This flaw allows a local user to crash or potentially cause a denial of service.

In the Linux kernel, the following vulnerability has been resolved: bpftool: Fix NULL pointer dereference when pin {PROG, MAP, LINK} without FILE When using bpftool to pin {PROG, MAP, LINK} without FILE, segmentation fault will occur. The reson is that the lack of FILE will cause strlen to trigger NULL pointer dereference. The corresponding stacktrace is shown below: do_pin do_pin_any do_pin_fd mount_bpffs_for_pin strlen(name) <- NULL pointer dereference Fix it by adding validation to the common process.

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Check for NULL cpu_buffer in ring_buffer_wake_waiters() On some machines the number of listed CPUs may be bigger than the actual CPUs that exist. The tracing subsystem allocates a per_cpu directory with access to the per CPU ring buffer via a cpuX file. But to save space, the ring buffer will only allocate buffers for online CPUs, even though the CPU array will be as big as the nr_cpu_ids. With the addition of waking waiters on the ring buffer when closing the file, the ring_buffer_wake_waiters() now needs to make sure that the buffer is allocated (with the irq_work allocated with it) before trying to wake waiters, as it will cause a NULL pointer dereference. While debugging this, I added a NULL check for the buffer itself (which is OK to do), and also NULL pointer checks against buffer->buffers (which is not fine, and will WARN) as well as making sure the CPU number passed in is within the nr_cpu_ids (which is also not fine if it isn't). Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=1204705

In the Linux kernel, the following vulnerability has been resolved: IB/hfi1: Correctly move list in sc_disable() Commit 13bac861952a ("IB/hfi1: Fix abba locking issue with sc_disable()") incorrectly tries to move a list from one list head to another. The result is a kernel crash. The crash is triggered when a link goes down and there are waiters for a send to complete. The following signature is seen: BUG: kernel NULL pointer dereference, address: 0000000000000030 [...] Call Trace: sc_disable+0x1ba/0x240 [hfi1] pio_freeze+0x3d/0x60 [hfi1] handle_freeze+0x27/0x1b0 [hfi1] process_one_work+0x1b0/0x380 ? process_one_work+0x380/0x380 worker_thread+0x30/0x360 ? process_one_work+0x380/0x380 kthread+0xd7/0x100 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 The fix is to use the correct call to move the list.

In the Linux kernel, the following vulnerability has been resolved: net, neigh: Fix null-ptr-deref in neigh_table_clear() When IPv6 module gets initialized but hits an error in the middle, kenel panic with: KASAN: null-ptr-deref in range [0x0000000000000598-0x000000000000059f] CPU: 1 PID: 361 Comm: insmod Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:__neigh_ifdown.isra.0+0x24b/0x370 RSP: 0018:ffff888012677908 EFLAGS: 00000202 ... Call Trace: <TASK> neigh_table_clear+0x94/0x2d0 ndisc_cleanup+0x27/0x40 [ipv6] inet6_init+0x21c/0x2cb [ipv6] do_one_initcall+0xd3/0x4d0 do_init_module+0x1ae/0x670 ... Kernel panic - not syncing: Fatal exception When ipv6 initialization fails, it will try to cleanup and calls: neigh_table_clear() neigh_ifdown(tbl, NULL) pneigh_queue_purge(&tbl->proxy_queue, dev_net(dev == NULL)) # dev_net(NULL) triggers null-ptr-deref. Fix it by passing NULL to pneigh_queue_purge() in neigh_ifdown() if dev is NULL, to make kernel not panic immediately.

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Fix null-ptr-deref when xps sysfs alloc failed There is a null-ptr-deref when xps sysfs alloc failed: BUG: KASAN: null-ptr-deref in sysfs_do_create_link_sd+0x40/0xd0 Read of size 8 at addr 0000000000000030 by task gssproxy/457 CPU: 5 PID: 457 Comm: gssproxy Not tainted 6.0.0-09040-g02357b27ee03 #9 Call Trace: <TASK> dump_stack_lvl+0x34/0x44 kasan_report+0xa3/0x120 sysfs_do_create_link_sd+0x40/0xd0 rpc_sysfs_client_setup+0x161/0x1b0 rpc_new_client+0x3fc/0x6e0 rpc_create_xprt+0x71/0x220 rpc_create+0x1d4/0x350 gssp_rpc_create+0xc3/0x160 set_gssp_clnt+0xbc/0x140 write_gssp+0x116/0x1a0 proc_reg_write+0xd6/0x130 vfs_write+0x177/0x690 ksys_write+0xb9/0x150 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 When the xprt_switch sysfs alloc failed, should not add xprt and switch sysfs to it, otherwise, maybe null-ptr-deref; also initialize the 'xps_sysfs' to NULL to avoid oops when destroy it.

In the Linux kernel, the following vulnerability has been resolved: can: af_can: fix NULL pointer dereference in can_rx_register() It causes NULL pointer dereference when testing as following: (a) use syscall(__NR_socket, 0x10ul, 3ul, 0) to create netlink socket. (b) use syscall(__NR_sendmsg, ...) to create bond link device and vxcan link device, and bind vxcan device to bond device (can also use ifenslave command to bind vxcan device to bond device). (c) use syscall(__NR_socket, 0x1dul, 3ul, 1) to create CAN socket. (d) use syscall(__NR_bind, ...) to bind the bond device to CAN socket. The bond device invokes the can-raw protocol registration interface to receive CAN packets. However, ml_priv is not allocated to the dev, dev_rcv_lists is assigned to NULL in can_rx_register(). In this case, it will occur the NULL pointer dereference issue. The following is the stack information: BUG: kernel NULL pointer dereference, address: 0000000000000008 PGD 122a4067 P4D 122a4067 PUD 1223c067 PMD 0 Oops: 0000 [#1] PREEMPT SMP RIP: 0010:can_rx_register+0x12d/0x1e0 Call Trace: <TASK> raw_enable_filters+0x8d/0x120 raw_enable_allfilters+0x3b/0x130 raw_bind+0x118/0x4f0 __sys_bind+0x163/0x1a0 __x64_sys_bind+0x1e/0x30 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK>

In the Linux kernel, the following vulnerability has been resolved: RDMA/hns: Fix NULL pointer problem in free_mr_init() Lock grab occurs in a concurrent scenario, resulting in stepping on a NULL pointer. It should be init mutex_init() first before use the lock. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Call trace: __mutex_lock.constprop.0+0xd0/0x5c0 __mutex_lock_slowpath+0x1c/0x2c mutex_lock+0x44/0x50 free_mr_send_cmd_to_hw+0x7c/0x1c0 [hns_roce_hw_v2] hns_roce_v2_dereg_mr+0x30/0x40 [hns_roce_hw_v2] hns_roce_dereg_mr+0x4c/0x130 [hns_roce_hw_v2] ib_dereg_mr_user+0x54/0x124 uverbs_free_mr+0x24/0x30 destroy_hw_idr_uobject+0x38/0x74 uverbs_destroy_uobject+0x48/0x1c4 uobj_destroy+0x74/0xcc ib_uverbs_cmd_verbs+0x368/0xbb0 ib_uverbs_ioctl+0xec/0x1a4 __arm64_sys_ioctl+0xb4/0x100 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0x58/0x190 do_el0_svc+0x30/0x90 el0_svc+0x2c/0xb4 el0t_64_sync_handler+0x1a4/0x1b0 el0t_64_sync+0x19c/0x1a0

In the Linux kernel, the following vulnerability has been resolved: cxl/region: Fix decoder allocation crash When an intermediate port's decoders have been exhausted by existing regions, and creating a new region with the port in question in it's hierarchical path is attempted, cxl_port_attach_region() fails to find a port decoder (as would be expected), and drops into the failure / cleanup path. However, during cleanup of the region reference, a sanity check attempts to dereference the decoder, which in the above case didn't exist. This causes a NULL pointer dereference BUG. To fix this, refactor the decoder allocation and de-allocation into helper routines, and in this 'free' routine, check that the decoder, @cxld, is valid before attempting any operations on it.

In the Linux kernel, the following vulnerability has been resolved: phy: qcom-qmp-combo: fix NULL-deref on runtime resume Commit fc64623637da ("phy: qcom-qmp-combo,usb: add support for separate PCS_USB region") started treating the PCS_USB registers as potentially separate from the PCS registers but used the wrong base when no PCS_USB offset has been provided. Fix the PCS_USB base used at runtime resume to prevent dereferencing a NULL pointer on platforms that do not provide a PCS_USB offset (e.g. SC7180).

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Fix null-ptr-deref in ib_core_cleanup() KASAN reported a null-ptr-deref error: KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f] CPU: 1 PID: 379 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:destroy_workqueue+0x2f/0x740 RSP: 0018:ffff888016137df8 EFLAGS: 00000202 ... Call Trace: ib_core_cleanup+0xa/0xa1 [ib_core] __do_sys_delete_module.constprop.0+0x34f/0x5b0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa1a0d221b7 ... It is because the fail of roce_gid_mgmt_init() is ignored: ib_core_init() roce_gid_mgmt_init() gid_cache_wq = alloc_ordered_workqueue # fail ... ib_core_cleanup() roce_gid_mgmt_cleanup() destroy_workqueue(gid_cache_wq) # destroy an unallocated wq Fix this by catching the fail of roce_gid_mgmt_init() in ib_core_init().

A NULL pointer dereference flaw was found in rawv6_push_pending_frames in net/ipv6/raw.c in the network subcomponent in the Linux kernel. This flaw causes the system to crash.

In the Linux kernel, the following vulnerability has been resolved: net: phy: fix null-ptr-deref while probe() failed I got a null-ptr-deref report as following when doing fault injection test: BUG: kernel NULL pointer dereference, address: 0000000000000058 Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 PID: 253 Comm: 507-spi-dm9051 Tainted: G B N 6.1.0-rc3+ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:klist_put+0x2d/0xd0 Call Trace: <TASK> klist_remove+0xf1/0x1c0 device_release_driver_internal+0x23e/0x2d0 bus_remove_device+0x1bd/0x240 device_del+0x357/0x770 phy_device_remove+0x11/0x30 mdiobus_unregister+0xa5/0x140 release_nodes+0x6a/0xa0 devres_release_all+0xf8/0x150 device_unbind_cleanup+0x19/0xd0 //probe path: phy_device_register() device_add() phy_connect phy_attach_direct() //set device driver probe() //it's failed, driver is not bound device_bind_driver() // probe failed, it's not called //remove path: phy_device_remove() device_del() device_release_driver_internal() __device_release_driver() //dev->drv is not NULL klist_remove() <- knode_driver is not added yet, cause null-ptr-deref In phy_attach_direct(), after setting the 'dev->driver', probe() fails, device_bind_driver() is not called, so the knode_driver->n_klist is not set, then it causes null-ptr-deref in __device_release_driver() while deleting device. Fix this by setting dev->driver to NULL in the error path in phy_attach_direct().

In the Linux kernel, the following vulnerability has been resolved: xen-netfront: Fix NULL sring after live migration A NAPI is setup for each network sring to poll data to kernel The sring with source host is destroyed before live migration and new sring with target host is setup after live migration. The NAPI for the old sring is not deleted until setup new sring with target host after migration. With busy_poll/busy_read enabled, the NAPI can be polled before got deleted when resume VM. BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 IP: xennet_poll+0xae/0xd20 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI Call Trace: finish_task_switch+0x71/0x230 timerqueue_del+0x1d/0x40 hrtimer_try_to_cancel+0xb5/0x110 xennet_alloc_rx_buffers+0x2a0/0x2a0 napi_busy_loop+0xdb/0x270 sock_poll+0x87/0x90 do_sys_poll+0x26f/0x580 tracing_map_insert+0x1d4/0x2f0 event_hist_trigger+0x14a/0x260 finish_task_switch+0x71/0x230 __schedule+0x256/0x890 recalc_sigpending+0x1b/0x50 xen_sched_clock+0x15/0x20 __rb_reserve_next+0x12d/0x140 ring_buffer_lock_reserve+0x123/0x3d0 event_triggers_call+0x87/0xb0 trace_event_buffer_commit+0x1c4/0x210 xen_clocksource_get_cycles+0x15/0x20 ktime_get_ts64+0x51/0xf0 SyS_ppoll+0x160/0x1a0 SyS_ppoll+0x160/0x1a0 do_syscall_64+0x73/0x130 entry_SYSCALL_64_after_hwframe+0x41/0xa6 ... RIP: xennet_poll+0xae/0xd20 RSP: ffffb4f041933900 CR2: 0000000000000008 ---[ end trace f8601785b354351c ]--- xen frontend should remove the NAPIs for the old srings before live migration as the bond srings are destroyed There is a tiny window between the srings are set to NULL and the NAPIs are disabled, It is safe as the NAPI threads are still frozen at that time

In the Linux kernel, the following vulnerability has been resolved: io_uring: Fix a null-ptr-deref in io_tctx_exit_cb() Syzkaller reports a NULL deref bug as follows: BUG: KASAN: null-ptr-deref in io_tctx_exit_cb+0x53/0xd3 Read of size 4 at addr 0000000000000138 by task file1/1955 CPU: 1 PID: 1955 Comm: file1 Not tainted 6.1.0-rc7-00103-gef4d3ea40565 #75 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0xcd/0x134 ? io_tctx_exit_cb+0x53/0xd3 kasan_report+0xbb/0x1f0 ? io_tctx_exit_cb+0x53/0xd3 kasan_check_range+0x140/0x190 io_tctx_exit_cb+0x53/0xd3 task_work_run+0x164/0x250 ? task_work_cancel+0x30/0x30 get_signal+0x1c3/0x2440 ? lock_downgrade+0x6e0/0x6e0 ? lock_downgrade+0x6e0/0x6e0 ? exit_signals+0x8b0/0x8b0 ? do_raw_read_unlock+0x3b/0x70 ? do_raw_spin_unlock+0x50/0x230 arch_do_signal_or_restart+0x82/0x2470 ? kmem_cache_free+0x260/0x4b0 ? putname+0xfe/0x140 ? get_sigframe_size+0x10/0x10 ? do_execveat_common.isra.0+0x226/0x710 ? lockdep_hardirqs_on+0x79/0x100 ? putname+0xfe/0x140 ? do_execveat_common.isra.0+0x238/0x710 exit_to_user_mode_prepare+0x15f/0x250 syscall_exit_to_user_mode+0x19/0x50 do_syscall_64+0x42/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0023:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 002b:00000000fffb7790 EFLAGS: 00000200 ORIG_RAX: 000000000000000b RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Kernel panic - not syncing: panic_on_warn set ... This happens because the adding of task_work from io_ring_exit_work() isn't synchronized with canceling all work items from eg exec. The execution of the two are ordered in that they are both run by the task itself, but if io_tctx_exit_cb() is queued while we're canceling all work items off exec AND gets executed when the task exits to userspace rather than in the main loop in io_uring_cancel_generic(), then we can find current->io_uring == NULL and hit the above crash. It's safe to add this NULL check here, because the execution of the two paths are done by the task itself. [axboe: add code comment and also put an explanation in the commit msg]

In the Linux kernel, the following vulnerability has been resolved: ASoC: rt711-sdca: fix kernel NULL pointer dereference when IO error The initial settings will be written before the codec probe function. But, the rt711->component doesn't be assigned yet. If IO error happened during initial settings operations, it will cause the kernel panic. This patch changed component->dev to slave->dev to fix this issue.

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_aspeed_vuart: Fix potential NULL dereference in aspeed_vuart_probe platform_get_resource() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: fbdev: Fix unregistering of framebuffers without device OF framebuffers do not have an underlying device in the Linux device hierarchy. Do a regular unregister call instead of hot unplugging such a non-existing device. Fixes a NULL dereference. An example error message on ppc64le is shown below. BUG: Kernel NULL pointer dereference on read at 0x00000060 Faulting instruction address: 0xc00000000080dfa4 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries [...] CPU: 2 PID: 139 Comm: systemd-udevd Not tainted 5.17.0-ae085d7f9365 #1 NIP: c00000000080dfa4 LR: c00000000080df9c CTR: c000000000797430 REGS: c000000004132fe0 TRAP: 0300 Not tainted (5.17.0-ae085d7f9365) MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 28228282 XER: 20000000 CFAR: c00000000000c80c DAR: 0000000000000060 DSISR: 40000000 IRQMASK: 0 GPR00: c00000000080df9c c000000004133280 c00000000169d200 0000000000000029 GPR04: 00000000ffffefff c000000004132f90 c000000004132f88 0000000000000000 GPR08: c0000000015658f8 c0000000015cd200 c0000000014f57d0 0000000048228283 GPR12: 0000000000000000 c00000003fffe300 0000000020000000 0000000000000000 GPR16: 0000000000000000 0000000113fc4a40 0000000000000005 0000000113fcfb80 GPR20: 000001000f7283b0 0000000000000000 c000000000e4a588 c000000000e4a5b0 GPR24: 0000000000000001 00000000000a0000 c008000000db0168 c0000000021f6ec0 GPR28: c0000000016d65a8 c000000004b36460 0000000000000000 c0000000016d64b0 NIP [c00000000080dfa4] do_remove_conflicting_framebuffers+0x184/0x1d0 [c000000004133280] [c00000000080df9c] do_remove_conflicting_framebuffers+0x17c/0x1d0 (unreliable) [c000000004133350] [c00000000080e4d0] remove_conflicting_framebuffers+0x60/0x150 [c0000000041333a0] [c00000000080e6f4] remove_conflicting_pci_framebuffers+0x134/0x1b0 [c000000004133450] [c008000000e70438] drm_aperture_remove_conflicting_pci_framebuffers+0x90/0x100 [drm] [c000000004133490] [c008000000da0ce4] bochs_pci_probe+0x6c/0xa64 [bochs] [...] [c000000004133db0] [c00000000002aaa0] system_call_exception+0x170/0x2d0 [c000000004133e10] [c00000000000c3cc] system_call_common+0xec/0x250 The bug [1] was introduced by commit 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal"). Most firmware framebuffers have an underlying platform device, which can be hot-unplugged before loading the native graphics driver. OF framebuffers do not (yet) have that device. Fix the code by unregistering the framebuffer as before without a hot unplug. Tested with 5.17 on qemu ppc64le emulation.

In the Linux kernel, the following vulnerability has been resolved: KVM: Don't null dereference ops->destroy A KVM device cleanup happens in either of two callbacks: 1) destroy() which is called when the VM is being destroyed; 2) release() which is called when a device fd is closed. Most KVM devices use 1) but Book3s's interrupt controller KVM devices (XICS, XIVE, XIVE-native) use 2) as they need to close and reopen during the machine execution. The error handling in kvm_ioctl_create_device() assumes destroy() is always defined which leads to NULL dereference as discovered by Syzkaller. This adds a checks for destroy!=NULL and adds a missing release(). This is not changing kvm_destroy_devices() as devices with defined release() should have been removed from the KVM devices list by then.

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: treat all calls not a bcall when bc_serv is NULL When a rdma server returns a fault format reply, nfs v3 client may treats it as a bcall when bc service is not exist. The debug message at rpcrdma_bc_receive_call are, [56579.837169] RPC: rpcrdma_bc_receive_call: callback XID 00000001, length=20 [56579.837174] RPC: rpcrdma_bc_receive_call: 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 After that, rpcrdma_bc_receive_call will meets NULL pointer as, [ 226.057890] BUG: unable to handle kernel NULL pointer dereference at 00000000000000c8 ... [ 226.058704] RIP: 0010:_raw_spin_lock+0xc/0x20 ... [ 226.059732] Call Trace: [ 226.059878] rpcrdma_bc_receive_call+0x138/0x327 [rpcrdma] [ 226.060011] __ib_process_cq+0x89/0x170 [ib_core] [ 226.060092] ib_cq_poll_work+0x26/0x80 [ib_core] [ 226.060257] process_one_work+0x1a7/0x360 [ 226.060367] ? create_worker+0x1a0/0x1a0 [ 226.060440] worker_thread+0x30/0x390 [ 226.060500] ? create_worker+0x1a0/0x1a0 [ 226.060574] kthread+0x116/0x130 [ 226.060661] ? kthread_flush_work_fn+0x10/0x10 [ 226.060724] ret_from_fork+0x35/0x40 ...

In the Linux kernel, the following vulnerability has been resolved: pinctrl: ralink: Check for null return of devm_kcalloc Because of the possible failure of the allocation, data->domains might be NULL pointer and will cause the dereference of the NULL pointer later. Therefore, it might be better to check it and directly return -ENOMEM without releasing data manually if fails, because the comment of the devm_kmalloc() says "Memory allocated with this function is automatically freed on driver detach.".

In the Linux kernel, the following vulnerability has been resolved: clk: Fix clk_hw_get_clk() when dev is NULL Any registered clk_core structure can have a NULL pointer in its dev field. While never actually documented, this is evidenced by the wide usage of clk_register and clk_hw_register with a NULL device pointer, and the fact that the core of_clk_hw_register() function also passes a NULL device pointer. A call to clk_hw_get_clk() on a clk_hw struct whose clk_core is in that case will result in a NULL pointer derefence when it calls dev_name() on that NULL device pointer. Add a test for this case and use NULL as the dev_id if the device pointer is NULL.