kernel/trace/ftrace.c in the Linux kernel before 2.6.35.5, when debugfs is enabled, does not properly handle interaction between mutex possession and llseek operations, which allows local users to cause a denial of service (NULL pointer dereference and outage of all function tracing files) via an lseek call on a file descriptor associated with the set_ftrace_filter file.

In the Linux kernel, the following vulnerability has been resolved: net: ll_temac: platform_get_resource replaced by wrong function The function platform_get_resource was replaced with devm_platform_ioremap_resource_byname and is called using 0 as name. This eventually ends up in platform_get_resource_byname in the call stack, where it causes a null pointer in strcmp. if (type == resource_type(r) && !strcmp(r->name, name)) It should have been replaced with devm_platform_ioremap_resource.

In the Linux kernel, the following vulnerability has been resolved: efi: fix panic in kdump kernel Check if get_next_variable() is actually valid pointer before calling it. In kdump kernel this method is set to NULL that causes panic during the kexec-ed kernel boot. Tested with QEMU and OVMF firmware.

In the Linux kernel, the following vulnerability has been resolved: usb: typec: altmodes/displayport: create sysfs nodes as driver's default device attribute group The DisplayPort driver's sysfs nodes may be present to the userspace before typec_altmode_set_drvdata() completes in dp_altmode_probe. This means that a sysfs read can trigger a NULL pointer error by deferencing dp->hpd in hpd_show or dp->lock in pin_assignment_show, as dev_get_drvdata() returns NULL in those cases. Remove manual sysfs node creation in favor of adding attribute group as default for devices bound to the driver. The ATTRIBUTE_GROUPS() macro is not used here otherwise the path to the sysfs nodes is no longer compliant with the ABI.

In the Linux kernel, the following vulnerability has been resolved: firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool() Commit 2e4955167ec5 ("firmware: qcom: scm: Fix __scm and waitq completion variable initialization") introduced a write barrier in probe function to store global '__scm' variable. We all known barriers are paired (see memory-barriers.txt: "Note that write barriers should normally be paired with read or address-dependency barriers"), therefore accessing it from concurrent contexts requires read barrier. Previous commit added such barrier in qcom_scm_is_available(), so let's use that directly. Lack of this read barrier can result in fetching stale '__scm' variable value, NULL, and dereferencing it. Note that barrier in qcom_scm_is_available() satisfies here the control dependency.

In the Linux kernel, the following vulnerability has been resolved: mlxbf_gige: stop interface during shutdown The mlxbf_gige driver intermittantly encounters a NULL pointer exception while the system is shutting down via "reboot" command. The mlxbf_driver will experience an exception right after executing its shutdown() method. One example of this exception is: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000070 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=000000011d373000 [0000000000000070] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 96000004 [#1] SMP CPU: 0 PID: 13 Comm: ksoftirqd/0 Tainted: G S OE 5.15.0-bf.6.gef6992a #1 Hardware name: https://www.mellanox.com BlueField SoC/BlueField SoC, BIOS 4.0.2.12669 Apr 21 2023 pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : mlxbf_gige_handle_tx_complete+0xc8/0x170 [mlxbf_gige] lr : mlxbf_gige_poll+0x54/0x160 [mlxbf_gige] sp : ffff8000080d3c10 x29: ffff8000080d3c10 x28: ffffcce72cbb7000 x27: ffff8000080d3d58 x26: ffff0000814e7340 x25: ffff331cd1a05000 x24: ffffcce72c4ea008 x23: ffff0000814e4b40 x22: ffff0000814e4d10 x21: ffff0000814e4128 x20: 0000000000000000 x19: ffff0000814e4a80 x18: ffffffffffffffff x17: 000000000000001c x16: ffffcce72b4553f4 x15: ffff80008805b8a7 x14: 0000000000000000 x13: 0000000000000030 x12: 0101010101010101 x11: 7f7f7f7f7f7f7f7f x10: c2ac898b17576267 x9 : ffffcce720fa5404 x8 : ffff000080812138 x7 : 0000000000002e9a x6 : 0000000000000080 x5 : ffff00008de3b000 x4 : 0000000000000000 x3 : 0000000000000001 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: mlxbf_gige_handle_tx_complete+0xc8/0x170 [mlxbf_gige] mlxbf_gige_poll+0x54/0x160 [mlxbf_gige] __napi_poll+0x40/0x1c8 net_rx_action+0x314/0x3a0 __do_softirq+0x128/0x334 run_ksoftirqd+0x54/0x6c smpboot_thread_fn+0x14c/0x190 kthread+0x10c/0x110 ret_from_fork+0x10/0x20 Code: 8b070000 f9000ea0 f95056c0 f86178a1 (b9407002) ---[ end trace 7cc3941aa0d8e6a4 ]--- Kernel panic - not syncing: Oops: Fatal exception in interrupt Kernel Offset: 0x4ce722520000 from 0xffff800008000000 PHYS_OFFSET: 0x80000000 CPU features: 0x000005c1,a3330e5a Memory Limit: none ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]--- During system shutdown, the mlxbf_gige driver's shutdown() is always executed. However, the driver's stop() method will only execute if networking interface configuration logic within the Linux distribution has been setup to do so. If shutdown() executes but stop() does not execute, NAPI remains enabled and this can lead to an exception if NAPI is scheduled while the hardware interface has only been partially deinitialized. The networking interface managed by the mlxbf_gige driver must be properly stopped during system shutdown so that IFF_UP is cleared, the hardware interface is put into a clean state, and NAPI is fully deinitialized.

In the Linux kernel, the following vulnerability has been resolved: fpga: region: add owner module and take its refcount The current implementation of the fpga region assumes that the low-level module registers a driver for the parent device and uses its owner pointer to take the module's refcount. This approach is problematic since it can lead to a null pointer dereference while attempting to get the region during programming if the parent device does not have a driver. To address this problem, add a module owner pointer to the fpga_region struct and use it to take the module's refcount. Modify the functions for registering a region to take an additional owner module parameter and rename them to avoid conflicts. Use the old function names for helper macros that automatically set the module that registers the region as the owner. This ensures compatibility with existing low-level control modules and reduces the chances of registering a region without setting the owner. Also, update the documentation to keep it consistent with the new interface for registering an fpga region.

In the Linux kernel, the following vulnerability has been resolved: spi: mchp-pci1xxx: Fix a possible null pointer dereference in pci1xxx_spi_probe In function pci1xxxx_spi_probe, there is a potential null pointer that may be caused by a failed memory allocation by the function devm_kzalloc. Hence, a null pointer check needs to be added to prevent null pointer dereferencing later in the code. To fix this issue, spi_bus->spi_int[iter] should be checked. The memory allocated by devm_kzalloc will be automatically released, so just directly return -ENOMEM without worrying about memory leaks.

In the Linux kernel, the following vulnerability has been resolved: mm: zswap: fix shrinker NULL crash with cgroup_disable=memory Christian reports a NULL deref in zswap that he bisected down to the zswap shrinker. The issue also cropped up in the bug trackers of libguestfs [1] and the Red Hat bugzilla [2]. The problem is that when memcg is disabled with the boot time flag, the zswap shrinker might get called with sc->memcg == NULL. This is okay in many places, like the lruvec operations. But it crashes in memcg_page_state() - which is only used due to the non-node accounting of cgroup's the zswap memory to begin with. Nhat spotted that the memcg can be NULL in the memcg-disabled case, and I was then able to reproduce the crash locally as well. [1] https://github.com/libguestfs/libguestfs/issues/139 [2] https://bugzilla.redhat.com/show_bug.cgi?id=2275252

In the Linux kernel, the following vulnerability has been resolved: mm/gup: handle NULL pages in unpin_user_pages() The recent addition of "pofs" (pages or folios) handling to gup has a flaw: it assumes that unpin_user_pages() handles NULL pages in the pages** array. That's not the case, as I discovered when I ran on a new configuration on my test machine. Fix this by skipping NULL pages in unpin_user_pages(), just like unpin_folios() already does. Details: when booting on x86 with "numa=fake=2 movablecore=4G" on Linux 6.12, and running this: tools/testing/selftests/mm/gup_longterm ...I get the following crash: BUG: kernel NULL pointer dereference, address: 0000000000000008 RIP: 0010:sanity_check_pinned_pages+0x3a/0x2d0 ... Call Trace: <TASK> ? __die_body+0x66/0xb0 ? page_fault_oops+0x30c/0x3b0 ? do_user_addr_fault+0x6c3/0x720 ? irqentry_enter+0x34/0x60 ? exc_page_fault+0x68/0x100 ? asm_exc_page_fault+0x22/0x30 ? sanity_check_pinned_pages+0x3a/0x2d0 unpin_user_pages+0x24/0xe0 check_and_migrate_movable_pages_or_folios+0x455/0x4b0 __gup_longterm_locked+0x3bf/0x820 ? mmap_read_lock_killable+0x12/0x50 ? __pfx_mmap_read_lock_killable+0x10/0x10 pin_user_pages+0x66/0xa0 gup_test_ioctl+0x358/0xb20 __se_sys_ioctl+0x6b/0xc0 do_syscall_64+0x7b/0x150 entry_SYSCALL_64_after_hwframe+0x76/0x7e

In the Linux kernel, the following vulnerability has been resolved: bpf: Mark raw_tp arguments with PTR_MAYBE_NULL Arguments to a raw tracepoint are tagged as trusted, which carries the semantics that the pointer will be non-NULL. However, in certain cases, a raw tracepoint argument may end up being NULL. More context about this issue is available in [0]. Thus, there is a discrepancy between the reality, that raw_tp arguments can actually be NULL, and the verifier's knowledge, that they are never NULL, causing explicit NULL checks to be deleted, and accesses to such pointers potentially crashing the kernel. To fix this, mark raw_tp arguments as PTR_MAYBE_NULL, and then special case the dereference and pointer arithmetic to permit it, and allow passing them into helpers/kfuncs; these exceptions are made for raw_tp programs only. Ensure that we don't do this when ref_obj_id > 0, as in that case this is an acquired object and doesn't need such adjustment. The reason we do mask_raw_tp_trusted_reg logic is because other will recheck in places whether the register is a trusted_reg, and then consider our register as untrusted when detecting the presence of the PTR_MAYBE_NULL flag. To allow safe dereference, we enable PROBE_MEM marking when we see loads into trusted pointers with PTR_MAYBE_NULL. While trusted raw_tp arguments can also be passed into helpers or kfuncs where such broken assumption may cause issues, a future patch set will tackle their case separately, as PTR_TO_BTF_ID (without PTR_TRUSTED) can already be passed into helpers and causes similar problems. Thus, they are left alone for now. It is possible that these checks also permit passing non-raw_tp args that are trusted PTR_TO_BTF_ID with null marking. In such a case, allowing dereference when pointer is NULL expands allowed behavior, so won't regress existing programs, and the case of passing these into helpers is the same as above and will be dealt with later. Also update the failure case in tp_btf_nullable selftest to capture the new behavior, as the verifier will no longer cause an error when directly dereference a raw tracepoint argument marked as __nullable. [0]: https://lore.kernel.org/bpf/ZrCZS6nisraEqehw@jlelli-thinkpadt14gen4.remote.csb

In the Linux kernel, the following vulnerability has been resolved: dmaengine: ti: edma: Add some null pointer checks to the edma_probe devm_kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity.

In the Linux kernel, the following vulnerability has been resolved: dm: call the resume method on internal suspend There is this reported crash when experimenting with the lvm2 testsuite. The list corruption is caused by the fact that the postsuspend and resume methods were not paired correctly; there were two consecutive calls to the origin_postsuspend function. The second call attempts to remove the "hash_list" entry from a list, while it was already removed by the first call. Fix __dm_internal_resume so that it calls the preresume and resume methods of the table's targets. If a preresume method of some target fails, we are in a tricky situation. We can't return an error because dm_internal_resume isn't supposed to return errors. We can't return success, because then the "resume" and "postsuspend" methods would not be paired correctly. So, we set the DMF_SUSPENDED flag and we fake normal suspend - it may confuse userspace tools, but it won't cause a kernel crash. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:56! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 1 PID: 8343 Comm: dmsetup Not tainted 6.8.0-rc6 #4 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 RIP: 0010:__list_del_entry_valid_or_report+0x77/0xc0 <snip> RSP: 0018:ffff8881b831bcc0 EFLAGS: 00010282 RAX: 000000000000004e RBX: ffff888143b6eb80 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff819053d0 RDI: 00000000ffffffff RBP: ffff8881b83a3400 R08: 00000000fffeffff R09: 0000000000000058 R10: 0000000000000000 R11: ffffffff81a24080 R12: 0000000000000001 R13: ffff88814538e000 R14: ffff888143bc6dc0 R15: ffffffffa02e4bb0 FS: 00000000f7c0f780(0000) GS:ffff8893f0a40000(0000) knlGS:0000000000000000 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000057fb5000 CR3: 0000000143474000 CR4: 00000000000006b0 Call Trace: <TASK> ? die+0x2d/0x80 ? do_trap+0xeb/0xf0 ? __list_del_entry_valid_or_report+0x77/0xc0 ? do_error_trap+0x60/0x80 ? __list_del_entry_valid_or_report+0x77/0xc0 ? exc_invalid_op+0x49/0x60 ? __list_del_entry_valid_or_report+0x77/0xc0 ? asm_exc_invalid_op+0x16/0x20 ? table_deps+0x1b0/0x1b0 [dm_mod] ? __list_del_entry_valid_or_report+0x77/0xc0 origin_postsuspend+0x1a/0x50 [dm_snapshot] dm_table_postsuspend_targets+0x34/0x50 [dm_mod] dm_suspend+0xd8/0xf0 [dm_mod] dev_suspend+0x1f2/0x2f0 [dm_mod] ? table_deps+0x1b0/0x1b0 [dm_mod] ctl_ioctl+0x300/0x5f0 [dm_mod] dm_compat_ctl_ioctl+0x7/0x10 [dm_mod] __x64_compat_sys_ioctl+0x104/0x170 do_syscall_64+0x184/0x1b0 entry_SYSCALL_64_after_hwframe+0x46/0x4e RIP: 0033:0xf7e6aead <snip> ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: serial: core: Clearing the circular buffer before NULLifying it The circular buffer is NULLified in uart_tty_port_shutdown() under the spin lock. However, the PM or other timer based callbacks may still trigger after this event without knowning that buffer pointer is not valid. Since the serial code is a bit inconsistent in checking the buffer state (some rely on the head-tail positions, some on the buffer pointer), it's better to have both aligned, i.e. buffer pointer to be NULL and head-tail possitions to be the same, meaning it's empty. This will prevent asynchronous calls to dereference NULL pointer as reported recently in 8250 case: BUG: kernel NULL pointer dereference, address: 00000cf5 Workqueue: pm pm_runtime_work EIP: serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809) ... ? serial8250_tx_chars (drivers/tty/serial/8250/8250_port.c:1809) __start_tx (drivers/tty/serial/8250/8250_port.c:1551) serial8250_start_tx (drivers/tty/serial/8250/8250_port.c:1654) serial_port_runtime_suspend (include/linux/serial_core.h:667 drivers/tty/serial/serial_port.c:63) __rpm_callback (drivers/base/power/runtime.c:393) ? serial_port_remove (drivers/tty/serial/serial_port.c:50) rpm_suspend (drivers/base/power/runtime.c:447) The proposed change will prevent ->start_tx() to be called during suspend on shut down port.

In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix kernel crash when 1588 is received on HIP08 devices The HIP08 devices does not register the ptp devices, so the hdev->ptp is NULL, but the hardware can receive 1588 messages, and set the HNS3_RXD_TS_VLD_B bit, so, if match this case, the access of hdev->ptp->flags will cause a kernel crash: [ 5888.946472] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018 [ 5888.946475] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018 ... [ 5889.266118] pc : hclge_ptp_get_rx_hwts+0x40/0x170 [hclge] [ 5889.272612] lr : hclge_ptp_get_rx_hwts+0x34/0x170 [hclge] [ 5889.279101] sp : ffff800012c3bc50 [ 5889.283516] x29: ffff800012c3bc50 x28: ffff2040002be040 [ 5889.289927] x27: ffff800009116484 x26: 0000000080007500 [ 5889.296333] x25: 0000000000000000 x24: ffff204001c6f000 [ 5889.302738] x23: ffff204144f53c00 x22: 0000000000000000 [ 5889.309134] x21: 0000000000000000 x20: ffff204004220080 [ 5889.315520] x19: ffff204144f53c00 x18: 0000000000000000 [ 5889.321897] x17: 0000000000000000 x16: 0000000000000000 [ 5889.328263] x15: 0000004000140ec8 x14: 0000000000000000 [ 5889.334617] x13: 0000000000000000 x12: 00000000010011df [ 5889.340965] x11: bbfeff4d22000000 x10: 0000000000000000 [ 5889.347303] x9 : ffff800009402124 x8 : 0200f78811dfbb4d [ 5889.353637] x7 : 2200000000191b01 x6 : ffff208002a7d480 [ 5889.359959] x5 : 0000000000000000 x4 : 0000000000000000 [ 5889.366271] x3 : 0000000000000000 x2 : 0000000000000000 [ 5889.372567] x1 : 0000000000000000 x0 : ffff20400095c080 [ 5889.378857] Call trace: [ 5889.382285] hclge_ptp_get_rx_hwts+0x40/0x170 [hclge] [ 5889.388304] hns3_handle_bdinfo+0x324/0x410 [hns3] [ 5889.394055] hns3_handle_rx_bd+0x60/0x150 [hns3] [ 5889.399624] hns3_clean_rx_ring+0x84/0x170 [hns3] [ 5889.405270] hns3_nic_common_poll+0xa8/0x220 [hns3] [ 5889.411084] napi_poll+0xcc/0x264 [ 5889.415329] net_rx_action+0xd4/0x21c [ 5889.419911] __do_softirq+0x130/0x358 [ 5889.424484] irq_exit+0x134/0x154 [ 5889.428700] __handle_domain_irq+0x88/0xf0 [ 5889.433684] gic_handle_irq+0x78/0x2c0 [ 5889.438319] el1_irq+0xb8/0x140 [ 5889.442354] arch_cpu_idle+0x18/0x40 [ 5889.446816] default_idle_call+0x5c/0x1c0 [ 5889.451714] cpuidle_idle_call+0x174/0x1b0 [ 5889.456692] do_idle+0xc8/0x160 [ 5889.460717] cpu_startup_entry+0x30/0xfc [ 5889.465523] secondary_start_kernel+0x158/0x1ec [ 5889.470936] Code: 97ffab78 f9411c14 91408294 f9457284 (f9400c80) [ 5889.477950] SMP: stopping secondary CPUs [ 5890.514626] SMP: failed to stop secondary CPUs 0-69,71-95 [ 5890.522951] Starting crashdump kernel...

In the Linux kernel, the following vulnerability has been resolved: usb: core: Prevent null pointer dereference in update_port_device_state Currently, the function update_port_device_state gets the usb_hub from udev->parent by calling usb_hub_to_struct_hub. However, in case the actconfig or the maxchild is 0, the usb_hub would be NULL and upon further accessing to get port_dev would result in null pointer dereference. Fix this by introducing an if check after the usb_hub is populated.

In the Linux kernel, the following vulnerability has been resolved: serial: max310x: fix NULL pointer dereference in I2C instantiation When trying to instantiate a max14830 device from userspace: echo max14830 0x60 > /sys/bus/i2c/devices/i2c-2/new_device we get the following error: Unable to handle kernel NULL pointer dereference at virtual address... ... Call trace: max310x_i2c_probe+0x48/0x170 [max310x] i2c_device_probe+0x150/0x2a0 ... Add check for validity of devtype to prevent the error, and abort probe with a meaningful error message.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: rfcomm: Fix null-ptr-deref in rfcomm_check_security During our fuzz testing of the connection and disconnection process at the RFCOMM layer, we discovered this bug. By comparing the packets from a normal connection and disconnection process with the testcase that triggered a KASAN report. We analyzed the cause of this bug as follows: 1. In the packets captured during a normal connection, the host sends a `Read Encryption Key Size` type of `HCI_CMD` packet (Command Opcode: 0x1408) to the controller to inquire the length of encryption key.After receiving this packet, the controller immediately replies with a Command Completepacket (Event Code: 0x0e) to return the Encryption Key Size. 2. In our fuzz test case, the timing of the controller's response to this packet was delayed to an unexpected point: after the RFCOMM and L2CAP layers had disconnected but before the HCI layer had disconnected. 3. After receiving the Encryption Key Size Response at the time described in point 2, the host still called the rfcomm_check_security function. However, by this time `struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;` had already been released, and when the function executed `return hci_conn_security(conn->hcon, d->sec_level, auth_type, d->out);`, specifically when accessing `conn->hcon`, a null-ptr-deref error occurred. To fix this bug, check if `sk->sk_state` is BT_CLOSED before calling rfcomm_recv_frame in rfcomm_process_rx.

In the Linux kernel, the following vulnerability has been resolved: iommufd: Fix iopt_access_list_id overwrite bug Syzkaller reported the following WARN_ON: WARNING: CPU: 1 PID: 4738 at drivers/iommu/iommufd/io_pagetable.c:1360 Call Trace: iommufd_access_change_ioas+0x2fe/0x4e0 iommufd_access_destroy_object+0x50/0xb0 iommufd_object_remove+0x2a3/0x490 iommufd_object_destroy_user iommufd_access_destroy+0x71/0xb0 iommufd_test_staccess_release+0x89/0xd0 __fput+0x272/0xb50 __fput_sync+0x4b/0x60 __do_sys_close __se_sys_close __x64_sys_close+0x8b/0x110 do_syscall_x64 The mismatch between the access pointer in the list and the passed-in pointer is resulting from an overwrite of access->iopt_access_list_id, in iopt_add_access(). Called from iommufd_access_change_ioas() when xa_alloc() succeeds but iopt_calculate_iova_alignment() fails. Add a new_id in iopt_add_access() and only update iopt_access_list_id when returning successfully.

In the Linux kernel, the following vulnerability has been resolved: spi: hisi-sfc-v3xx: Return IRQ_NONE if no interrupts were detected Return IRQ_NONE from the interrupt handler when no interrupt was detected. Because an empty interrupt will cause a null pointer error: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 Call trace: complete+0x54/0x100 hisi_sfc_v3xx_isr+0x2c/0x40 [spi_hisi_sfc_v3xx] __handle_irq_event_percpu+0x64/0x1e0 handle_irq_event+0x7c/0x1cc

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix NULL checks for adev->dm.dc in amdgpu_dm_fini() Since 'adev->dm.dc' in amdgpu_dm_fini() might turn out to be NULL before the call to dc_enable_dmub_notifications(), check beforehand to ensure there will not be a possible NULL-ptr-deref there. Also, since commit 1e88eb1b2c25 ("drm/amd/display: Drop CONFIG_DRM_AMD_DC_HDCP") there are two separate checks for NULL in 'adev->dm.dc' before dc_deinit_callbacks() and dc_dmub_srv_destroy(). Clean up by combining them all under one 'if'. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE.

In the Linux kernel, the following vulnerability has been resolved: cpufreq: brcmstb-avs-cpufreq: add check for cpufreq_cpu_get's return value cpufreq_cpu_get may return NULL. To avoid NULL-dereference check it and return 0 in case of error. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: clk: zynq: Prevent null pointer dereference caused by kmalloc failure The kmalloc() in zynq_clk_setup() will return null if the physical memory has run out. As a result, if we use snprintf() to write data to the null address, the null pointer dereference bug will happen. This patch uses a stack variable to replace the kmalloc().

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix NULL pointer dereference in f2fs_submit_page_write() BUG: kernel NULL pointer dereference, address: 0000000000000014 RIP: 0010:f2fs_submit_page_write+0x6cf/0x780 [f2fs] Call Trace: <TASK> ? show_regs+0x6e/0x80 ? __die+0x29/0x70 ? page_fault_oops+0x154/0x4a0 ? prb_read_valid+0x20/0x30 ? __irq_work_queue_local+0x39/0xd0 ? irq_work_queue+0x36/0x70 ? do_user_addr_fault+0x314/0x6c0 ? exc_page_fault+0x7d/0x190 ? asm_exc_page_fault+0x2b/0x30 ? f2fs_submit_page_write+0x6cf/0x780 [f2fs] ? f2fs_submit_page_write+0x736/0x780 [f2fs] do_write_page+0x50/0x170 [f2fs] f2fs_outplace_write_data+0x61/0xb0 [f2fs] f2fs_do_write_data_page+0x3f8/0x660 [f2fs] f2fs_write_single_data_page+0x5bb/0x7a0 [f2fs] f2fs_write_cache_pages+0x3da/0xbe0 [f2fs] ... It is possible that other threads have added this fio to io->bio and submitted the io->bio before entering f2fs_submit_page_write(). At this point io->bio = NULL. If is_end_zone_blkaddr(sbi, fio->new_blkaddr) of this fio is true, then an NULL pointer dereference error occurs at bio_get(io->bio). The original code for determining zone end was after "out:", which would have missed some fio who is zone end. I've moved this code before "skip:" to make sure it's done for each fio.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Add a dc_state NULL check in dc_state_release [How] Check wheather state is NULL before releasing it.

In the Linux kernel, the following vulnerability has been resolved: nbd: null check for nla_nest_start nla_nest_start() may fail and return NULL. Insert a check and set errno based on other call sites within the same source code.

In the Linux kernel, the following vulnerability has been resolved: pmdomain: arm: Fix NULL dereference on scmi_perf_domain removal On unloading of the scmi_perf_domain module got the below splat, when in the DT provided to the system under test the '#power-domain-cells' property was missing. Indeed, this particular setup causes the probe to bail out early without giving any error, which leads to the ->remove() callback gets to run too, but without all the expected initialized structures in place. Add a check and bail out early on remove too. Call trace: scmi_perf_domain_remove+0x28/0x70 [scmi_perf_domain] scmi_dev_remove+0x28/0x40 [scmi_core] device_remove+0x54/0x90 device_release_driver_internal+0x1dc/0x240 driver_detach+0x58/0xa8 bus_remove_driver+0x78/0x108 driver_unregister+0x38/0x70 scmi_driver_unregister+0x28/0x180 [scmi_core] scmi_perf_domain_driver_exit+0x18/0xb78 [scmi_perf_domain] __arm64_sys_delete_module+0x1a8/0x2c0 invoke_syscall+0x50/0x128 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x34/0xb8 el0t_64_sync_handler+0x100/0x130 el0t_64_sync+0x190/0x198 Code: a90153f3 f9403c14 f9414800 955f8a05 (b9400a80) ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: HID: i2c-hid-of: fix NULL-deref on failed power up A while back the I2C HID implementation was split in an ACPI and OF part, but the new OF driver never initialises the client pointer which is dereferenced on power-up failures.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix potential null pointer dereference in dc_dmub_srv Fixes potential null pointer dereference warnings in the dc_dmub_srv_cmd_list_queue_execute() and dc_dmub_srv_is_hw_pwr_up() functions. In both functions, the 'dc_dmub_srv' variable was being dereferenced before it was checked for null. This could lead to a null pointer dereference if 'dc_dmub_srv' is null. The fix is to check if 'dc_dmub_srv' is null before dereferencing it. Thus moving the null checks for 'dc_dmub_srv' to the beginning of the functions to ensure that 'dc_dmub_srv' is not null when it is dereferenced. Found by smatch & thus fixing the below: drivers/gpu/drm/amd/amdgpu/../display/dc/dc_dmub_srv.c:133 dc_dmub_srv_cmd_list_queue_execute() warn: variable dereferenced before check 'dc_dmub_srv' (see line 128) drivers/gpu/drm/amd/amdgpu/../display/dc/dc_dmub_srv.c:1167 dc_dmub_srv_is_hw_pwr_up() warn: variable dereferenced before check 'dc_dmub_srv' (see line 1164)

In the Linux kernel, the following vulnerability has been resolved: nfp: flower: handle acti_netdevs allocation failure The kmalloc_array() in nfp_fl_lag_do_work() will return null, if the physical memory has run out. As a result, if we dereference the acti_netdevs, the null pointer dereference bugs will happen. This patch adds a check to judge whether allocation failure occurs. If it happens, the delayed work will be rescheduled and try again.

A vulnerability was found in Linux Kernel where in the spk_ttyio_receive_buf2() function, it would dereference spk_ttyio_synth without checking whether it is NULL or not, and may lead to a NULL-ptr deref crash.

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix NULL domain on device release In the kdump kernel, the IOMMU operates in deferred_attach mode. In this mode, info->domain may not yet be assigned by the time the release_device function is called. It leads to the following crash in the crash kernel: BUG: kernel NULL pointer dereference, address: 000000000000003c ... RIP: 0010:do_raw_spin_lock+0xa/0xa0 ... _raw_spin_lock_irqsave+0x1b/0x30 intel_iommu_release_device+0x96/0x170 iommu_deinit_device+0x39/0xf0 __iommu_group_remove_device+0xa0/0xd0 iommu_bus_notifier+0x55/0xb0 notifier_call_chain+0x5a/0xd0 blocking_notifier_call_chain+0x41/0x60 bus_notify+0x34/0x50 device_del+0x269/0x3d0 pci_remove_bus_device+0x77/0x100 p2sb_bar+0xae/0x1d0 ... i801_probe+0x423/0x740 Use the release_domain mechanism to fix it. The scalable mode context entry which is not part of release domain should be cleared in release_device().

In the Linux kernel, the following vulnerability has been resolved: net: phy: qcom: at803x: fix kernel panic with at8031_probe On reworking and splitting the at803x driver, in splitting function of at803x PHYs it was added a NULL dereference bug where priv is referenced before it's actually allocated and then is tried to write to for the is_1000basex and is_fiber variables in the case of at8031, writing on the wrong address. Fix this by correctly setting priv local variable only after at803x_probe is called and actually allocates priv in the phydev struct.

In the Linux kernel, the following vulnerability has been resolved: wifi: brcm80211: handle pmk_op allocation failure The kzalloc() in brcmf_pmksa_v3_op() will return null if the physical memory has run out. As a result, if we dereference the null value, the null pointer dereference bug will happen. Return -ENOMEM from brcmf_pmksa_v3_op() if kzalloc() fails for pmk_op.

In the Linux kernel, the following vulnerability has been resolved: backlight: hx8357: Fix potential NULL pointer dereference The "im" pins are optional. Add missing check in the hx8357_probe().

In the Linux kernel, the following vulnerability has been resolved: RDMA/srpt: Support specifying the srpt_service_guid parameter Make loading ib_srpt with this parameter set work. The current behavior is that setting that parameter while loading the ib_srpt kernel module triggers the following kernel crash: BUG: kernel NULL pointer dereference, address: 0000000000000000 Call Trace: <TASK> parse_one+0x18c/0x1d0 parse_args+0xe1/0x230 load_module+0x8de/0xa60 init_module_from_file+0x8b/0xd0 idempotent_init_module+0x181/0x240 __x64_sys_finit_module+0x5a/0xb0 do_syscall_64+0x5f/0xe0 entry_SYSCALL_64_after_hwframe+0x6e/0x76

In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix possible use-after-free and null-ptr-deref The pernet operations structure for the subsystem must be registered before registering the generic netlink family.

In the Linux kernel, the following vulnerability has been resolved: powercap: intel_rapl: Fix a NULL pointer dereference A NULL pointer dereference is triggered when probing the MMIO RAPL driver on platforms with CPU ID not listed in intel_rapl_common CPU model list. This is because the intel_rapl_common module still probes on such platforms even if 'defaults_msr' is not set after commit 1488ac990ac8 ("powercap: intel_rapl: Allow probing without CPUID match"). Thus the MMIO RAPL rp->priv->defaults is NULL when registering to RAPL framework. Fix the problem by adding sanity check to ensure rp->priv->rapl_defaults is always valid.

In the Linux kernel, the following vulnerability has been resolved: vfio/fsl-mc: Block calling interrupt handler without trigger The eventfd_ctx trigger pointer of the vfio_fsl_mc_irq object is initially NULL and may become NULL if the user sets the trigger eventfd to -1. The interrupt handler itself is guaranteed that trigger is always valid between request_irq() and free_irq(), but the loopback testing mechanisms to invoke the handler function need to test the trigger. The triggering and setting ioctl paths both make use of igate and are therefore mutually exclusive. The vfio-fsl-mc driver does not make use of irqfds, nor does it support any sort of masking operations, therefore unlike vfio-pci and vfio-platform, the flow can remain essentially unchanged.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/pm: Fix NULL pointer dereference when get power limit Because powerplay_table initialization is skipped under sriov case, We check and set default lower and upper OD value if powerplay_table is NULL.

In the Linux kernel, the following vulnerability has been resolved: vfio/platform: Create persistent IRQ handlers The vfio-platform SET_IRQS ioctl currently allows loopback triggering of an interrupt before a signaling eventfd has been configured by the user, which thereby allows a NULL pointer dereference. Rather than register the IRQ relative to a valid trigger, register all IRQs in a disabled state in the device open path. This allows mask operations on the IRQ to nest within the overall enable state governed by a valid eventfd signal. This decouples @masked, protected by the @locked spinlock from @trigger, protected via the @igate mutex. In doing so, it's guaranteed that changes to @trigger cannot race the IRQ handlers because the IRQ handler is synchronously disabled before modifying the trigger, and loopback triggering of the IRQ via ioctl is safe due to serialization with trigger changes via igate. For compatibility, request_irq() failures are maintained to be local to the SET_IRQS ioctl rather than a fatal error in the open device path. This allows, for example, a userspace driver with polling mode support to continue to work regardless of moving the request_irq() call site. This necessarily blocks all SET_IRQS access to the failed index.

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend In current scenario if Plug-out and Plug-In performed continuously there could be a chance while checking for dwc->gadget_driver in dwc3_gadget_suspend, a NULL pointer dereference may occur. Call Stack: CPU1: CPU2: gadget_unbind_driver dwc3_suspend_common dwc3_gadget_stop dwc3_gadget_suspend dwc3_disconnect_gadget CPU1 basically clears the variable and CPU2 checks the variable. Consider CPU1 is running and right before gadget_driver is cleared and in parallel CPU2 executes dwc3_gadget_suspend where it finds dwc->gadget_driver which is not NULL and resumes execution and then CPU1 completes execution. CPU2 executes dwc3_disconnect_gadget where it checks dwc->gadget_driver is already NULL because of which the NULL pointer deference occur.

In the Linux kernel, the following vulnerability has been resolved: thunderbolt: Fix NULL pointer dereference in tb_port_update_credits() Olliver reported that his system crashes when plugging in Thunderbolt 1 device: BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:tb_port_do_update_credits+0x1b/0x130 [thunderbolt] Call Trace: <TASK> ? __die+0x23/0x70 ? page_fault_oops+0x171/0x4e0 ? exc_page_fault+0x7f/0x180 ? asm_exc_page_fault+0x26/0x30 ? tb_port_do_update_credits+0x1b/0x130 ? tb_switch_update_link_attributes+0x83/0xd0 tb_switch_add+0x7a2/0xfe0 tb_scan_port+0x236/0x6f0 tb_handle_hotplug+0x6db/0x900 process_one_work+0x171/0x340 worker_thread+0x27b/0x3a0 ? __pfx_worker_thread+0x10/0x10 kthread+0xe5/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> This is due the fact that some Thunderbolt 1 devices only have one lane adapter. Fix this by checking for the lane 1 before we read its credits.

In the Linux kernel, the following vulnerability has been resolved: wireguard: netlink: access device through ctx instead of peer The previous commit fixed a bug that led to a NULL peer->device being dereferenced. It's actually easier and faster performance-wise to instead get the device from ctx->wg. This semantically makes more sense too, since ctx->wg->peer_allowedips.seq is compared with ctx->allowedips_seq, basing them both in ctx. This also acts as a defence in depth provision against freed peers.

In the Linux kernel, the following vulnerability has been resolved: scsi: target: pscsi: Fix bio_put() for error case As of commit 066ff571011d ("block: turn bio_kmalloc into a simple kmalloc wrapper"), a bio allocated by bio_kmalloc() must be freed by bio_uninit() and kfree(). That is not done properly for the error case, hitting WARN and NULL pointer dereference in bio_free().

In the Linux kernel, the following vulnerability has been resolved: usb: dwc2: host: Fix dereference issue in DDMA completion flow. Fixed variable dereference issue in DDMA completion flow.

Null pointer reference in some Intel(R) Graphics Drivers for Windows* before version 26.20.100.7212 and before version Linux kernel version 5.5 may allow a privileged user to potentially enable a denial of service via local access.

In the Linux kernel, the following vulnerability has been resolved: HID: nvidia-shield: Add missing null pointer checks to LED initialization devm_kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity. [jkosina@suse.com: tweak changelog a bit]

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fixed integer types and null check locations [why]: issues fixed: - comparison with wider integer type in loop condition which can cause infinite loops - pointer dereference before null check

In the Linux kernel, the following vulnerability has been resolved: net: phy: fix phy_get_internal_delay accessing an empty array The phy_get_internal_delay function could try to access to an empty array in the case that the driver is calling phy_get_internal_delay without defining delay_values and rx-internal-delay-ps or tx-internal-delay-ps is defined to 0 in the device-tree. This will lead to "unable to handle kernel NULL pointer dereference at virtual address 0". To avoid this kernel oops, the test should be delay >= 0. As there is already delay < 0 test just before, the test could only be size == 0.