In the Linux kernel, the following vulnerability has been resolved: drm/vrr: Set VRR capable prop only if it is attached to connector VRR capable property is not attached by default to the connector It is attached only if VRR is supported. So if the driver tries to call drm core set prop function without it being attached that causes NULL dereference.

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: fix pointer derefs in error cases of rpcrdma_ep_create If there are failures then we must not leave the non-NULL pointers with the error value, otherwise `rpcrdma_ep_destroy` gets confused and tries free them, resulting in an Oops.

In the Linux kernel, the following vulnerability has been resolved: USB: host: isp116x: check return value after calling platform_get_resource() It will cause null-ptr-deref if platform_get_resource() returns NULL, we need check the return value.

In the Linux kernel, the following vulnerability has been resolved: drm: mxsfb: Fix NULL pointer dereference mxsfb should not ever dereference the NULL pointer which drm_atomic_get_new_bridge_state is allowed to return. Assume a fixed format instead.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/hdmi: check return value after calling platform_get_resource_byname() It will cause null-ptr-deref if platform_get_resource_byname() returns NULL, we need check the return value. Patchwork: https://patchwork.freedesktop.org/patch/482992/

In the Linux kernel, the following vulnerability has been resolved: ice: Add check for kzalloc Add the check for the return value of kzalloc in order to avoid NULL pointer dereference. Moreover, use the goto-label to share the clean code.

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: rtc: mt6397: check return value after calling platform_get_resource() It will cause null-ptr-deref if platform_get_resource() returns NULL, we need check the return value.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dp: populate connector of struct dp_panel DP CTS test case 4.2.2.6 has valid edid with bad checksum on purpose and expect DP source return correct checksum. During drm edid read, correct edid checksum is calculated and stored at connector::real_edid_checksum. The problem is struct dp_panel::connector never be assigned, instead the connector is stored in struct msm_dp::connector. When we run compliance testing test case 4.2.2.6 dp_panel_handle_sink_request() won't have a valid edid set in struct dp_panel::edid so we'll try to use the connectors real_edid_checksum and hit a NULL pointer dereference error because the connector pointer is never assigned. Changes in V2: -- populate panel connector at msm_dp_modeset_init() instead of at dp_panel_read_sink_caps() Changes in V3: -- remove unhelpful kernel crash trace commit text -- remove renaming dp_display parameter to dp Changes in V4: -- add more details to commit text Changes in v10: -- group into one series Changes in v11: -- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read Signee-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>

In the Linux kernel, the following vulnerability has been resolved: cxl/region: Fix null pointer dereference for resetting decoder Not all decoders have a reset callback. The CXL specification allows a host bridge with a single root port to have no explicit HDM decoders. Currently the region driver assumes there are none. As such the CXL core creates a special pass through decoder instance without a commit/reset callback. Prior to this patch, the ->reset() callback was called unconditionally when calling cxl_region_decode_reset. Thus a configuration with 1 Host Bridge, 1 Root Port, and one directly attached CXL type 3 device or multiple CXL type 3 devices attached to downstream ports of a switch can cause a null pointer dereference. Before the fix, a kernel crash was observed when we destroy the region, and a pass through decoder is reset. The issue can be reproduced as below, 1) create a region with a CXL setup which includes a HB with a single root port under which a memdev is attached directly. 2) destroy the region with cxl destroy-region regionX -f.

In the Linux kernel, the following vulnerability has been resolved: drm/panel: ili9341: fix optional regulator handling If the optional regulator lookup fails, reset the pointer to NULL. Other functions such as mipi_dbi_poweron_reset_conditional() only do a NULL pointer check and will otherwise dereference the error pointer.

In the Linux kernel, the following vulnerability has been resolved: pinctrl: single: fix potential NULL dereference Added checking of pointer "function" in pcs_set_mux(). pinmux_generic_get_function() can return NULL and the pointer "function" was dereferenced without checking against NULL. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: thermal/int340x_thermal: handle data_vault when the value is ZERO_SIZE_PTR In some case, the GDDV returns a package with a buffer which has zero length. It causes that kmemdup() returns ZERO_SIZE_PTR (0x10). Then the data_vault_read() got NULL point dereference problem when accessing the 0x10 value in data_vault. [ 71.024560] BUG: kernel NULL pointer dereference, address: 0000000000000010 This patch uses ZERO_OR_NULL_PTR() for checking ZERO_SIZE_PTR or NULL value in data_vault.

In the Linux kernel, the following vulnerability has been resolved: staging: vchiq_core: handle NULL result of find_service_by_handle In case of an invalid handle the function find_servive_by_handle returns NULL. So take care of this and avoid a NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: hwmon: (coretemp) Check for null before removing sysfs attrs If coretemp_add_core() gets an error then pdata->core_data[indx] is already NULL and has been kfreed. Don't pass that to sysfs_remove_group() as that will crash in sysfs_remove_group(). [Shortened for readability] [91854.020159] sysfs: cannot create duplicate filename '/devices/platform/coretemp.0/hwmon/hwmon2/temp20_label' <cpu offline> [91855.126115] BUG: kernel NULL pointer dereference, address: 0000000000000188 [91855.165103] #PF: supervisor read access in kernel mode [91855.194506] #PF: error_code(0x0000) - not-present page [91855.224445] PGD 0 P4D 0 [91855.238508] Oops: 0000 [#1] PREEMPT SMP PTI ... [91855.342716] RIP: 0010:sysfs_remove_group+0xc/0x80 ... [91855.796571] Call Trace: [91855.810524] coretemp_cpu_offline+0x12b/0x1dd [coretemp] [91855.841738] ? coretemp_cpu_online+0x180/0x180 [coretemp] [91855.871107] cpuhp_invoke_callback+0x105/0x4b0 [91855.893432] cpuhp_thread_fun+0x8e/0x150 ... Fix this by checking for NULL first.

In the Linux kernel, the following vulnerability has been resolved: net: phy: micrel: Allow probing without .driver_data Currently, if the .probe element is present in the phy_driver structure and the .driver_data is not, a NULL pointer dereference happens. Allow passing .probe without .driver_data by inserting NULL checks for priv->type.

In the Linux kernel, the following vulnerability has been resolved: ovl: fix NULL pointer dereference in copy up warning This patch is fixing a NULL pointer dereference to get a recently introduced warning message working.

In the Linux kernel, the following vulnerability has been resolved: spi: spi-fsl-qspi: check return value after calling platform_get_resource_byname() It will cause null-ptr-deref if platform_get_resource_byname() returns NULL, we need check the return value.

In the Linux kernel, the following vulnerability has been resolved: spi: bcm2835: bcm2835_spi_handle_err(): fix NULL pointer deref for non DMA transfers In case a IRQ based transfer times out the bcm2835_spi_handle_err() function is called. Since commit 1513ceee70f2 ("spi: bcm2835: Drop dma_pending flag") the TX and RX DMA transfers are unconditionally canceled, leading to NULL pointer derefs if ctlr->dma_tx or ctlr->dma_rx are not set. Fix the NULL pointer deref by checking that ctlr->dma_tx and ctlr->dma_rx are valid pointers before accessing them.

In the Linux kernel, the following vulnerability has been resolved: soc: ti: ti_sci_pm_domains: Check for null return of devm_kcalloc The allocation funciton devm_kcalloc may fail and return a null pointer, which would cause a null-pointer dereference later. It might be better to check it and directly return -ENOMEM just like the usage of devm_kcalloc in previous code.

In the Linux kernel before 6.1.6, a NULL pointer dereference bug in the traffic control subsystem allows an unprivileged user to trigger a denial of service (system crash) via a crafted traffic control configuration that is set up with "tc qdisc" and "tc class" commands. This affects qdisc_graft in net/sched/sch_api.c.

In the Linux kernel, the following vulnerability has been resolved: sfc: fix null pointer dereference in efx_hard_start_xmit Trying to get the channel from the tx_queue variable here is wrong because we can only be here if tx_queue is NULL, so we shouldn't dereference it. As the above comment in the code says, this is very unlikely to happen, but it's wrong anyway so let's fix it. I hit this issue because of a different bug that caused tx_queue to be NULL. If that happens, this is the error message that we get here: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 [...] RIP: 0010:efx_hard_start_xmit+0x153/0x170 [sfc]

In the Linux kernel, the following vulnerability has been resolved: s390/dasd: fix Oops in dasd_alias_get_start_dev due to missing pavgroup Fix Oops in dasd_alias_get_start_dev() function caused by the pavgroup pointer being NULL. The pavgroup pointer is checked on the entrance of the function but without the lcu->lock being held. Therefore there is a race window between dasd_alias_get_start_dev() and _lcu_update() which sets pavgroup to NULL with the lcu->lock held. Fix by checking the pavgroup pointer with lcu->lock held.

In the Linux kernel, the following vulnerability has been resolved: lib/test_hmm.c: handle src_pfns and dst_pfns allocation failure The kcalloc() in dmirror_device_evict_chunk() will return null if the physical memory has run out. As a result, if src_pfns or dst_pfns is dereferenced, the null pointer dereference bug will happen. Moreover, the device is going away. If the kcalloc() fails, the pages mapping a chunk could not be evicted. So add a __GFP_NOFAIL flag in kcalloc(). Finally, as there is no need to have physically contiguous memory, Switch kcalloc() to kvcalloc() in order to avoid failing allocations.

A flaw NULL Pointer Dereference in the Linux kernel NTFS3 driver function attr_punch_hole() was found. A local user could use this flaw to crash the system.

The Linux kernel before version 5.8 is vulnerable to a NULL pointer dereference in drivers/tty/serial/8250/8250_core.c:serial8250_isa_init_ports() that allows local users to cause a denial of service by using the p->serial_in pointer which uninitialized.

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: tracing/timerlat: Move hrtimer_init to timerlat_fd open() Currently, the timerlat's hrtimer is initialized at the first read of timerlat_fd, and destroyed at close(). It works, but it causes an error if the user program open() and close() the file without reading. Here's an example: # echo NO_OSNOISE_WORKLOAD > /sys/kernel/debug/tracing/osnoise/options # echo timerlat > /sys/kernel/debug/tracing/current_tracer # cat <<EOF > ./timerlat_load.py # !/usr/bin/env python3 timerlat_fd = open("/sys/kernel/tracing/osnoise/per_cpu/cpu0/timerlat_fd", 'r') timerlat_fd.close(); EOF # ./taskset -c 0 ./timerlat_load.py <BOOM> BUG: kernel NULL pointer dereference, address: 0000000000000010 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 2673 Comm: python3 Not tainted 6.6.13-200.fc39.x86_64 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 04/01/2014 RIP: 0010:hrtimer_active+0xd/0x50 Code: 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 48 8b 57 30 <8b> 42 10 a8 01 74 09 f3 90 8b 42 10 a8 01 75 f7 80 7f 38 00 75 1d RSP: 0018:ffffb031009b7e10 EFLAGS: 00010286 RAX: 000000000002db00 RBX: ffff9118f786db08 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9117a0e64400 RDI: ffff9118f786db08 RBP: ffff9118f786db80 R08: ffff9117a0ddd420 R09: ffff9117804d4f70 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9118f786db08 R13: ffff91178fdd5e20 R14: ffff9117840978c0 R15: 0000000000000000 FS: 00007f2ffbab1740(0000) GS:ffff9118f7840000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 00000001b402e000 CR4: 0000000000750ee0 PKRU: 55555554 Call Trace: <TASK> ? __die+0x23/0x70 ? page_fault_oops+0x171/0x4e0 ? srso_alias_return_thunk+0x5/0x7f ? avc_has_extended_perms+0x237/0x520 ? exc_page_fault+0x7f/0x180 ? asm_exc_page_fault+0x26/0x30 ? hrtimer_active+0xd/0x50 hrtimer_cancel+0x15/0x40 timerlat_fd_release+0x48/0xe0 __fput+0xf5/0x290 __x64_sys_close+0x3d/0x80 do_syscall_64+0x60/0x90 ? srso_alias_return_thunk+0x5/0x7f ? __x64_sys_ioctl+0x72/0xd0 ? srso_alias_return_thunk+0x5/0x7f ? syscall_exit_to_user_mode+0x2b/0x40 ? srso_alias_return_thunk+0x5/0x7f ? do_syscall_64+0x6c/0x90 ? srso_alias_return_thunk+0x5/0x7f ? exit_to_user_mode_prepare+0x142/0x1f0 ? srso_alias_return_thunk+0x5/0x7f ? syscall_exit_to_user_mode+0x2b/0x40 ? srso_alias_return_thunk+0x5/0x7f ? do_syscall_64+0x6c/0x90 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 RIP: 0033:0x7f2ffb321594 Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d d5 cd 0d 00 00 74 13 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 3c c3 0f 1f 00 55 48 89 e5 48 83 ec 10 89 7d RSP: 002b:00007ffe8d8eef18 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 00007f2ffba4e668 RCX: 00007f2ffb321594 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffe8d8eef40 R08: 0000000000000000 R09: 0000000000000000 R10: 55c926e3167eae79 R11: 0000000000000202 R12: 0000000000000003 R13: 00007ffe8d8ef030 R14: 0000000000000000 R15: 00007f2ffba4e668 </TASK> CR2: 0000000000000010 ---[ end trace 0000000000000000 ]--- Move hrtimer_init to timerlat_fd open() to avoid this problem.

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: 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: perf: RISCV: Fix panic on pmu overflow handler (1 << idx) of int is not desired when setting bits in unsigned long overflowed_ctrs, use BIT() instead. This panic happens when running 'perf record -e branches' on sophgo sg2042. [ 273.311852] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000098 [ 273.320851] Oops [#1] [ 273.323179] Modules linked in: [ 273.326303] CPU: 0 PID: 1475 Comm: perf Not tainted 6.6.0-rc3+ #9 [ 273.332521] Hardware name: Sophgo Mango (DT) [ 273.336878] epc : riscv_pmu_ctr_get_width_mask+0x8/0x62 [ 273.342291] ra : pmu_sbi_ovf_handler+0x2e0/0x34e [ 273.347091] epc : ffffffff80aecd98 ra : ffffffff80aee056 sp : fffffff6e36928b0 [ 273.354454] gp : ffffffff821f82d0 tp : ffffffd90c353200 t0 : 0000002ade4f9978 [ 273.361815] t1 : 0000000000504d55 t2 : ffffffff8016cd8c s0 : fffffff6e3692a70 [ 273.369180] s1 : 0000000000000020 a0 : 0000000000000000 a1 : 00001a8e81800000 [ 273.376540] a2 : 0000003c00070198 a3 : 0000003c00db75a4 a4 : 0000000000000015 [ 273.383901] a5 : ffffffd7ff8804b0 a6 : 0000000000000015 a7 : 000000000000002a [ 273.391327] s2 : 000000000000ffff s3 : 0000000000000000 s4 : ffffffd7ff8803b0 [ 273.398773] s5 : 0000000000504d55 s6 : ffffffd905069800 s7 : ffffffff821fe210 [ 273.406139] s8 : 000000007fffffff s9 : ffffffd7ff8803b0 s10: ffffffd903f29098 [ 273.413660] s11: 0000000080000000 t3 : 0000000000000003 t4 : ffffffff8017a0ca [ 273.421022] t5 : ffffffff8023cfc2 t6 : ffffffd9040780e8 [ 273.426437] status: 0000000200000100 badaddr: 0000000000000098 cause: 000000000000000d [ 273.434512] [<ffffffff80aecd98>] riscv_pmu_ctr_get_width_mask+0x8/0x62 [ 273.441169] [<ffffffff80076bd8>] handle_percpu_devid_irq+0x98/0x1ee [ 273.447562] [<ffffffff80071158>] generic_handle_domain_irq+0x28/0x36 [ 273.454151] [<ffffffff8047a99a>] riscv_intc_irq+0x36/0x4e [ 273.459659] [<ffffffff80c944de>] handle_riscv_irq+0x4a/0x74 [ 273.465442] [<ffffffff80c94c48>] do_irq+0x62/0x92 [ 273.470360] Code: 0420 60a2 6402 5529 0141 8082 0013 0000 0013 0000 (6d5c) b783 [ 273.477921] ---[ end trace 0000000000000000 ]--- [ 273.482630] Kernel panic - not syncing: Fatal exception in interrupt

In the Linux kernel, the following vulnerability has been resolved: erofs: fix inconsistent per-file compression format EROFS can select compression algorithms on a per-file basis, and each per-file compression algorithm needs to be marked in the on-disk superblock for initialization. However, syzkaller can generate inconsistent crafted images that use an unsupported algorithmtype for specific inodes, e.g. use MicroLZMA algorithmtype even it's not set in `sbi->available_compr_algs`. This can lead to an unexpected "BUG: kernel NULL pointer dereference" if the corresponding decompressor isn't built-in. Fix this by checking against `sbi->available_compr_algs` for each m_algorithmformat request. Incorrect !erofs_sb_has_compr_cfgs preset bitmap is now fixed together since it was harmless previously.

The XFS_IS_REALTIME_INODE macro in fs/xfs/xfs_linux.h in the Linux kernel before 4.13.2 does not verify that a filesystem has a realtime device, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) via vectors related to setting an RHINHERIT flag on a directory.

A NULL pointer dereference issue was found in KVM when releasing a vCPU with dirty ring support enabled. This flaw allows an unprivileged local attacker on the host to issue specific ioctl calls, causing a kernel oops condition that results in a denial of service.

In the Linux kernel, the following vulnerability has been resolved: sfc: fix NULL dereferences in ef100_process_design_param() Since cited commit, ef100_probe_main() and hence also ef100_check_design_params() run before efx->net_dev is created; consequently, we cannot netif_set_tso_max_size() or _segs() at this point. Move those netif calls to ef100_probe_netdev(), and also replace netif_err within the design params code with pci_err.

A security flaw was discovered in the nl80211_set_rekey_data() function in net/wireless/nl80211.c in the Linux kernel through 4.13.3. This function does not check whether the required attributes are present in a Netlink request. This request can be issued by a user with the CAP_NET_ADMIN capability and may result in a NULL pointer dereference and system crash.

The assoc_array_insert_into_terminal_node function in lib/assoc_array.c in the Linux kernel before 4.13.11 mishandles node splitting, which allows local users to cause a denial of service (NULL pointer dereference and panic) via a crafted application, as demonstrated by the keyring key type, and key addition and link creation operations.

The keyctl_read_key function in security/keys/keyctl.c in the Key Management subcomponent in the Linux kernel before 4.13.5 does not properly consider that a key may be possessed but negatively instantiated, which allows local users to cause a denial of service (OOPS and system crash) via a crafted KEYCTL_READ operation.

In the Linux kernel, the following vulnerability has been resolved: can: dev: can_get_echo_skb(): prevent call to kfree_skb() in hard IRQ context If a driver calls can_get_echo_skb() during a hardware IRQ (which is often, but not always, the case), the 'WARN_ON(in_irq)' in net/core/skbuff.c#skb_release_head_state() might be triggered, under network congestion circumstances, together with the potential risk of a NULL pointer dereference. The root cause of this issue is the call to kfree_skb() instead of dev_kfree_skb_irq() in net/core/dev.c#enqueue_to_backlog(). This patch prevents the skb to be freed within the call to netif_rx() by incrementing its reference count with skb_get(). The skb is finally freed by one of the in-irq-context safe functions: dev_consume_skb_any() or dev_kfree_skb_any(). The "any" version is used because some drivers might call can_get_echo_skb() in a normal context. The reason for this issue to occur is that initially, in the core network stack, loopback skb were not supposed to be received in hardware IRQ context. The CAN stack is an exeption. This bug was previously reported back in 2017 in [1] but the proposed patch never got accepted. While [1] directly modifies net/core/dev.c, we try to propose here a smoother modification local to CAN network stack (the assumption behind is that only CAN devices are affected by this issue). [1] http://lore.kernel.org/r/57a3ffb6-3309-3ad5-5a34-e93c3fe3614d@cetitec.com

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: nfs: fix panic when nfs4_ff_layout_prepare_ds() fails We've been seeing the following panic in production BUG: kernel NULL pointer dereference, address: 0000000000000065 PGD 2f485f067 P4D 2f485f067 PUD 2cc5d8067 PMD 0 RIP: 0010:ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles] Call Trace: <TASK> ? __die+0x78/0xc0 ? page_fault_oops+0x286/0x380 ? __rpc_execute+0x2c3/0x470 [sunrpc] ? rpc_new_task+0x42/0x1c0 [sunrpc] ? exc_page_fault+0x5d/0x110 ? asm_exc_page_fault+0x22/0x30 ? ff_layout_free_layoutreturn+0x110/0x110 [nfs_layout_flexfiles] ? ff_layout_cancel_io+0x3a/0x90 [nfs_layout_flexfiles] ? ff_layout_cancel_io+0x6f/0x90 [nfs_layout_flexfiles] pnfs_mark_matching_lsegs_return+0x1b0/0x360 [nfsv4] pnfs_error_mark_layout_for_return+0x9e/0x110 [nfsv4] ? ff_layout_send_layouterror+0x50/0x160 [nfs_layout_flexfiles] nfs4_ff_layout_prepare_ds+0x11f/0x290 [nfs_layout_flexfiles] ff_layout_pg_init_write+0xf0/0x1f0 [nfs_layout_flexfiles] __nfs_pageio_add_request+0x154/0x6c0 [nfs] nfs_pageio_add_request+0x26b/0x380 [nfs] nfs_do_writepage+0x111/0x1e0 [nfs] nfs_writepages_callback+0xf/0x30 [nfs] write_cache_pages+0x17f/0x380 ? nfs_pageio_init_write+0x50/0x50 [nfs] ? nfs_writepages+0x6d/0x210 [nfs] ? nfs_writepages+0x6d/0x210 [nfs] nfs_writepages+0x125/0x210 [nfs] do_writepages+0x67/0x220 ? generic_perform_write+0x14b/0x210 filemap_fdatawrite_wbc+0x5b/0x80 file_write_and_wait_range+0x6d/0xc0 nfs_file_fsync+0x81/0x170 [nfs] ? nfs_file_mmap+0x60/0x60 [nfs] __x64_sys_fsync+0x53/0x90 do_syscall_64+0x3d/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Inspecting the core with drgn I was able to pull this >>> prog.crashed_thread().stack_trace()[0] #0 at 0xffffffffa079657a (ff_layout_cancel_io+0x3a/0x84) in ff_layout_cancel_io at fs/nfs/flexfilelayout/flexfilelayout.c:2021:27 >>> prog.crashed_thread().stack_trace()[0]['idx'] (u32)1 >>> prog.crashed_thread().stack_trace()[0]['flseg'].mirror_array[1].mirror_ds (struct nfs4_ff_layout_ds *)0xffffffffffffffed This is clear from the stack trace, we call nfs4_ff_layout_prepare_ds() which could error out initializing the mirror_ds, and then we go to clean it all up and our check is only for if (!mirror->mirror_ds). This is inconsistent with the rest of the users of mirror_ds, which have if (IS_ERR_OR_NULL(mirror_ds)) to keep from tripping over this exact scenario. Fix this up in ff_layout_cancel_io() to make sure we don't panic when we get an error. I also spot checked all the other instances of checking mirror_ds and we appear to be doing the correct checks everywhere, only unconditionally dereferencing mirror_ds when we know it would be valid.

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: 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/sched: fix null-ptr-deref in init entity The bug can be triggered by sending an amdgpu_cs_wait_ioctl to the AMDGPU DRM driver on any ASICs with valid context. The bug was reported by Joonkyo Jung <joonkyoj@yonsei.ac.kr>. For example the following code: static void Syzkaller2(int fd) { union drm_amdgpu_ctx arg1; union drm_amdgpu_wait_cs arg2; arg1.in.op = AMDGPU_CTX_OP_ALLOC_CTX; ret = drmIoctl(fd, 0x140106442 /* amdgpu_ctx_ioctl */, &arg1); arg2.in.handle = 0x0; arg2.in.timeout = 0x2000000000000; arg2.in.ip_type = AMD_IP_VPE /* 0x9 */; arg2->in.ip_instance = 0x0; arg2.in.ring = 0x0; arg2.in.ctx_id = arg1.out.alloc.ctx_id; drmIoctl(fd, 0xc0206449 /* AMDGPU_WAIT_CS * /, &arg2); } The ioctl AMDGPU_WAIT_CS without previously submitted job could be assumed that the error should be returned, but the following commit 1decbf6bb0b4dc56c9da6c5e57b994ebfc2be3aa modified the logic and allowed to have sched_rq equal to NULL. As a result when there is no job the ioctl AMDGPU_WAIT_CS returns success. The change fixes null-ptr-deref in init entity and the stack below demonstrates the error condition: [ +0.000007] BUG: kernel NULL pointer dereference, address: 0000000000000028 [ +0.007086] #PF: supervisor read access in kernel mode [ +0.005234] #PF: error_code(0x0000) - not-present page [ +0.005232] PGD 0 P4D 0 [ +0.002501] Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI [ +0.005034] CPU: 10 PID: 9229 Comm: amd_basic Tainted: G B W L 6.7.0+ #4 [ +0.007797] Hardware name: ASUS System Product Name/ROG STRIX B550-F GAMING (WI-FI), BIOS 1401 12/03/2020 [ +0.009798] RIP: 0010:drm_sched_entity_init+0x2d3/0x420 [gpu_sched] [ +0.006426] Code: 80 00 00 00 00 00 00 00 e8 1a 81 82 e0 49 89 9c 24 c0 00 00 00 4c 89 ef e8 4a 80 82 e0 49 8b 5d 00 48 8d 7b 28 e8 3d 80 82 e0 <48> 83 7b 28 00 0f 84 28 01 00 00 4d 8d ac 24 98 00 00 00 49 8d 5c [ +0.019094] RSP: 0018:ffffc90014c1fa40 EFLAGS: 00010282 [ +0.005237] RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8113f3fa [ +0.007326] RDX: fffffbfff0a7889d RSI: 0000000000000008 RDI: ffffffff853c44e0 [ +0.007264] RBP: ffffc90014c1fa80 R08: 0000000000000001 R09: fffffbfff0a7889c [ +0.007266] R10: ffffffff853c44e7 R11: 0000000000000001 R12: ffff8881a719b010 [ +0.007263] R13: ffff88810d412748 R14: 0000000000000002 R15: 0000000000000000 [ +0.007264] FS: 00007ffff7045540(0000) GS:ffff8883cc900000(0000) knlGS:0000000000000000 [ +0.008236] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ +0.005851] CR2: 0000000000000028 CR3: 000000011912e000 CR4: 0000000000350ef0 [ +0.007175] Call Trace: [ +0.002561] <TASK> [ +0.002141] ? show_regs+0x6a/0x80 [ +0.003473] ? __die+0x25/0x70 [ +0.003124] ? page_fault_oops+0x214/0x720 [ +0.004179] ? preempt_count_sub+0x18/0xc0 [ +0.004093] ? __pfx_page_fault_oops+0x10/0x10 [ +0.004590] ? srso_return_thunk+0x5/0x5f [ +0.004000] ? vprintk_default+0x1d/0x30 [ +0.004063] ? srso_return_thunk+0x5/0x5f [ +0.004087] ? vprintk+0x5c/0x90 [ +0.003296] ? drm_sched_entity_init+0x2d3/0x420 [gpu_sched] [ +0.005807] ? srso_return_thunk+0x5/0x5f [ +0.004090] ? _printk+0xb3/0xe0 [ +0.003293] ? __pfx__printk+0x10/0x10 [ +0.003735] ? asm_sysvec_apic_timer_interrupt+0x1b/0x20 [ +0.005482] ? do_user_addr_fault+0x345/0x770 [ +0.004361] ? exc_page_fault+0x64/0xf0 [ +0.003972] ? asm_exc_page_fault+0x27/0x30 [ +0.004271] ? add_taint+0x2a/0xa0 [ +0.003476] ? drm_sched_entity_init+0x2d3/0x420 [gpu_sched] [ +0.005812] amdgpu_ctx_get_entity+0x3f9/0x770 [amdgpu] [ +0.009530] ? finish_task_switch.isra.0+0x129/0x470 [ +0.005068] ? __pfx_amdgpu_ctx_get_entity+0x10/0x10 [amdgpu] [ +0.010063] ? __kasan_check_write+0x14/0x20 [ +0.004356] ? srso_return_thunk+0x5/0x5f [ +0.004001] ? mutex_unlock+0x81/0xd0 [ +0.003802] ? srso_return_thunk+0x5/0x5f [ +0.004096] amdgpu_cs_wait_ioctl+0xf6/0x270 [amdgpu] [ +0.009355] ? __pfx_ ---truncated---

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: 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: netfs, fscache: Prevent Oops in fscache_put_cache() This function dereferences "cache" and then checks if it's IS_ERR_OR_NULL(). Check first, then dereference.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix late derefrence 'dsc' check in 'link_set_dsc_pps_packet()' In link_set_dsc_pps_packet(), 'struct display_stream_compressor *dsc' was dereferenced in a DC_LOGGER_INIT(dsc->ctx->logger); before the 'dsc' NULL pointer check. Fixes the below: drivers/gpu/drm/amd/amdgpu/../display/dc/link/link_dpms.c:905 link_set_dsc_pps_packet() warn: variable dereferenced before check 'dsc' (see line 903)

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix re-attachment branch in bpf_tracing_prog_attach The following case can cause a crash due to missing attach_btf: 1) load rawtp program 2) load fentry program with rawtp as target_fd 3) create tracing link for fentry program with target_fd = 0 4) repeat 3 In the end we have: - prog->aux->dst_trampoline == NULL - tgt_prog == NULL (because we did not provide target_fd to link_create) - prog->aux->attach_btf == NULL (the program was loaded with attach_prog_fd=X) - the program was loaded for tgt_prog but we have no way to find out which one BUG: kernel NULL pointer dereference, address: 0000000000000058 Call Trace: <TASK> ? __die+0x20/0x70 ? page_fault_oops+0x15b/0x430 ? fixup_exception+0x22/0x330 ? exc_page_fault+0x6f/0x170 ? asm_exc_page_fault+0x22/0x30 ? bpf_tracing_prog_attach+0x279/0x560 ? btf_obj_id+0x5/0x10 bpf_tracing_prog_attach+0x439/0x560 __sys_bpf+0x1cf4/0x2de0 __x64_sys_bpf+0x1c/0x30 do_syscall_64+0x41/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 Return -EINVAL in this situation.