In the Linux kernel, the following vulnerability has been resolved: drm: bridge: cdns-mhdp8546: Fix possible null pointer dereference In cdns_mhdp_atomic_enable(), the return value of drm_mode_duplicate() is assigned to mhdp_state->current_mode, and there is a dereference of it in drm_mode_set_name(), which will lead to a NULL pointer dereference on failure of drm_mode_duplicate(). Fix this bug add a check of mhdp_state->current_mode.

In the Linux kernel, the following vulnerability has been resolved: greybus: lights: check return of get_channel_from_mode If channel for the given node is not found we return null from get_channel_from_mode. Make sure we validate the return pointer before using it in two of the missing places. This was originally reported in [0]: Found by Linux Verification Center (linuxtesting.org) with SVACE. [0] https://lore.kernel.org/all/20240301190425.120605-1-m.lobanov@rosalinux.ru

Address read vulnerability in the communication module. Impact: Successful exploitation of this vulnerability may affect availability.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix netif state handling mlx5e_suspend cleans resources only if netif_device_present() returns true. However, mlx5e_resume changes the state of netif, via mlx5e_nic_enable, only if reg_state == NETREG_REGISTERED. In the below case, the above leads to NULL-ptr Oops[1] and memory leaks: mlx5e_probe _mlx5e_resume mlx5e_attach_netdev mlx5e_nic_enable <-- netdev not reg, not calling netif_device_attach() register_netdev <-- failed for some reason. ERROR_FLOW: _mlx5e_suspend <-- netif_device_present return false, resources aren't freed :( Hence, clean resources in this case as well. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0010 [#1] SMP CPU: 2 PID: 9345 Comm: test-ovs-ct-gen Not tainted 6.5.0_for_upstream_min_debug_2023_09_05_16_01 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:0x0 Code: Unable to access opcode bytes at0xffffffffffffffd6. RSP: 0018:ffff888178aaf758 EFLAGS: 00010246 Call Trace: <TASK> ? __die+0x20/0x60 ? page_fault_oops+0x14c/0x3c0 ? exc_page_fault+0x75/0x140 ? asm_exc_page_fault+0x22/0x30 notifier_call_chain+0x35/0xb0 blocking_notifier_call_chain+0x3d/0x60 mlx5_blocking_notifier_call_chain+0x22/0x30 [mlx5_core] mlx5_core_uplink_netdev_event_replay+0x3e/0x60 [mlx5_core] mlx5_mdev_netdev_track+0x53/0x60 [mlx5_ib] mlx5_ib_roce_init+0xc3/0x340 [mlx5_ib] __mlx5_ib_add+0x34/0xd0 [mlx5_ib] mlx5r_probe+0xe1/0x210 [mlx5_ib] ? auxiliary_match_id+0x6a/0x90 auxiliary_bus_probe+0x38/0x80 ? driver_sysfs_add+0x51/0x80 really_probe+0xc9/0x3e0 ? driver_probe_device+0x90/0x90 __driver_probe_device+0x80/0x160 driver_probe_device+0x1e/0x90 __device_attach_driver+0x7d/0x100 bus_for_each_drv+0x80/0xd0 __device_attach+0xbc/0x1f0 bus_probe_device+0x86/0xa0 device_add+0x637/0x840 __auxiliary_device_add+0x3b/0xa0 add_adev+0xc9/0x140 [mlx5_core] mlx5_rescan_drivers_locked+0x22a/0x310 [mlx5_core] mlx5_register_device+0x53/0xa0 [mlx5_core] mlx5_init_one_devl_locked+0x5c4/0x9c0 [mlx5_core] mlx5_init_one+0x3b/0x60 [mlx5_core] probe_one+0x44c/0x730 [mlx5_core] local_pci_probe+0x3e/0x90 pci_device_probe+0xbf/0x210 ? kernfs_create_link+0x5d/0xa0 ? sysfs_do_create_link_sd+0x60/0xc0 really_probe+0xc9/0x3e0 ? driver_probe_device+0x90/0x90 __driver_probe_device+0x80/0x160 driver_probe_device+0x1e/0x90 __device_attach_driver+0x7d/0x100 bus_for_each_drv+0x80/0xd0 __device_attach+0xbc/0x1f0 pci_bus_add_device+0x54/0x80 pci_iov_add_virtfn+0x2e6/0x320 sriov_enable+0x208/0x420 mlx5_core_sriov_configure+0x9e/0x200 [mlx5_core] sriov_numvfs_store+0xae/0x1a0 kernfs_fop_write_iter+0x10c/0x1a0 vfs_write+0x291/0x3c0 ksys_write+0x5f/0xe0 do_syscall_64+0x3d/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 CR2: 0000000000000000 ---[ end trace 0000000000000000 ]---

When a transaction is committed, C Xenstored will first check the quota is correct before attempting to commit any nodes. It would be possible that accounting is temporarily negative if a node has been removed outside of the transaction. Unfortunately, some versions of C Xenstored are assuming that the quota cannot be negative and are using assert() to confirm it. This will lead to C Xenstored crash when tools are built without -DNDEBUG (this is the default).

In the Linux kernel, the following vulnerability has been resolved: libbpf: Prevent null-pointer dereference when prog to load has no BTF In bpf_objec_load_prog(), there's no guarantee that obj->btf is non-NULL when passing it to btf__fd(), and this function does not perform any check before dereferencing its argument (as bpf_object__btf_fd() used to do). As a consequence, we get segmentation fault errors in bpftool (for example) when trying to load programs that come without BTF information. v2: Keep btf__fd() in the fix instead of reverting to bpf_object__btf_fd().

In the Linux kernel, the following vulnerability has been resolved: drm/msm/a6xx: Avoid a nullptr dereference when speedbin setting fails Calling a6xx_destroy() before adreno_gpu_init() leads to a null pointer dereference on: msm_gpu_cleanup() : platform_set_drvdata(gpu->pdev, NULL); as gpu->pdev is only assigned in: a6xx_gpu_init() |_ adreno_gpu_init |_ msm_gpu_init() Instead of relying on handwavy null checks down the cleanup chain, explicitly de-allocate the LLC data and free a6xx_gpu instead. Patchwork: https://patchwork.freedesktop.org/patch/588919/

In the Linux kernel, the following vulnerability has been resolved: drm: vc4: Fix possible null pointer dereference In vc4_hdmi_audio_init() of_get_address() may return NULL which is later dereferenced. Fix this bug by adding NULL check. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Check 'folio' pointer for NULL It can be NULL if bmap is called.

In the Linux kernel, the following vulnerability has been resolved: media: atomisp: ssh_css: Fix a null-pointer dereference in load_video_binaries The allocation failure of mycs->yuv_scaler_binary in load_video_binaries() is followed with a dereference of mycs->yuv_scaler_binary after the following call chain: sh_css_pipe_load_binaries() |-> load_video_binaries(mycs->yuv_scaler_binary == NULL) | |-> sh_css_pipe_unload_binaries() |-> unload_video_binaries() In unload_video_binaries(), it calls to ia_css_binary_unload with argument &pipe->pipe_settings.video.yuv_scaler_binary[i], which refers to the same memory slot as mycs->yuv_scaler_binary. Thus, a null-pointer dereference is triggered.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Add callback function pointer check before its call In dpu_core_irq_callback_handler() callback function pointer is compared to NULL, but then callback function is unconditionally called by this pointer. Fix this bug by adding conditional return. Found by Linux Verification Center (linuxtesting.org) with SVACE. Patchwork: https://patchwork.freedesktop.org/patch/588237/

In the Linux kernel, the following vulnerability has been resolved: thermal/drivers/tsens: Fix null pointer dereference compute_intercept_slope() is called from calibrate_8960() (in tsens-8960.c) as compute_intercept_slope(priv, p1, NULL, ONE_PT_CALIB) which lead to null pointer dereference (if DEBUG or DYNAMIC_DEBUG set). Fix this bug by adding null pointer check. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: pcie: handle randbuf allocation failure The kzalloc() in brcmf_pcie_download_fw_nvram() will return null if the physical memory has run out. As a result, if we use get_random_bytes() to generate random bytes in the randbuf, the null pointer dereference bug will happen. In order to prevent allocation failure, this patch adds a separate function using buffer on kernel stack to generate random bytes in the randbuf, which could prevent the kernel stack from overflow.

In the Linux kernel, the following vulnerability has been resolved: ASoC: qcom: Fix NULL Dereference in asoc_qcom_lpass_cpu_platform_probe() A devm_kzalloc() in asoc_qcom_lpass_cpu_platform_probe() could possibly return NULL pointer. NULL Pointer Dereference may be triggerred without addtional check. Add a NULL check for the returned pointer.

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: iommu/arm-smmu: Use the correct type in nvidia_smmu_context_fault() This was missed because of the function pointer indirection. nvidia_smmu_context_fault() is also installed as a irq function, and the 'void *' was changed to a struct arm_smmu_domain. Since the iommu_domain is embedded at a non-zero offset this causes nvidia_smmu_context_fault() to miscompute the offset. Fixup the types. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000120 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, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000107c9f000 [0000000000000120] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: CPU: 1 PID: 47 Comm: kworker/u25:0 Not tainted 6.9.0-0.rc7.58.eln136.aarch64 #1 Hardware name: Unknown NVIDIA Jetson Orin NX/NVIDIA Jetson Orin NX, BIOS 3.1-32827747 03/19/2023 Workqueue: events_unbound deferred_probe_work_func pstate: 604000c9 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : nvidia_smmu_context_fault+0x1c/0x158 lr : __free_irq+0x1d4/0x2e8 sp : ffff80008044b6f0 x29: ffff80008044b6f0 x28: ffff000080a60b18 x27: ffffd32b5172e970 x26: 0000000000000000 x25: ffff0000802f5aac x24: ffff0000802f5a30 x23: ffff0000802f5b60 x22: 0000000000000057 x21: 0000000000000000 x20: ffff0000802f5a00 x19: ffff000087d4cd80 x18: ffffffffffffffff x17: 6234362066666666 x16: 6630303078302d30 x15: ffff00008156d888 x14: 0000000000000000 x13: ffff0000801db910 x12: ffff00008156d6d0 x11: 0000000000000003 x10: ffff0000801db918 x9 : ffffd32b50f94d9c x8 : 1fffe0001032fda1 x7 : ffff00008197ed00 x6 : 000000000000000f x5 : 000000000000010e x4 : 000000000000010e x3 : 0000000000000000 x2 : ffffd32b51720cd8 x1 : ffff000087e6f700 x0 : 0000000000000057 Call trace: nvidia_smmu_context_fault+0x1c/0x158 __free_irq+0x1d4/0x2e8 free_irq+0x3c/0x80 devm_free_irq+0x64/0xa8 arm_smmu_domain_free+0xc4/0x158 iommu_domain_free+0x44/0xa0 iommu_deinit_device+0xd0/0xf8 __iommu_group_remove_device+0xcc/0xe0 iommu_bus_notifier+0x64/0xa8 notifier_call_chain+0x78/0x148 blocking_notifier_call_chain+0x4c/0x90 bus_notify+0x44/0x70 device_del+0x264/0x3e8 pci_remove_bus_device+0x84/0x120 pci_remove_root_bus+0x5c/0xc0 dw_pcie_host_deinit+0x38/0xe0 tegra_pcie_config_rp+0xc0/0x1f0 tegra_pcie_dw_probe+0x34c/0x700 platform_probe+0x70/0xe8 really_probe+0xc8/0x3a0 __driver_probe_device+0x84/0x160 driver_probe_device+0x44/0x130 __device_attach_driver+0xc4/0x170 bus_for_each_drv+0x90/0x100 __device_attach+0xa8/0x1c8 device_initial_probe+0x1c/0x30 bus_probe_device+0xb0/0xc0 deferred_probe_work_func+0xbc/0x120 process_one_work+0x194/0x490 worker_thread+0x284/0x3b0 kthread+0xf4/0x108 ret_from_fork+0x10/0x20 Code: a9b97bfd 910003fd a9025bf5 f85a0035 (b94122a1)

In the Linux kernel, the following vulnerability has been resolved: sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() It was possible to have pick_eevdf() return NULL, which then causes a NULL-deref. This turned out to be due to entity_eligible() returning falsely negative because of a s64 multiplcation overflow. Specifically, reweight_eevdf() computes the vlag without considering the limit placed upon vlag as update_entity_lag() does, and then the scaling multiplication (remember that weight is 20bit fixed point) can overflow. This then leads to the new vruntime being weird which then causes the above entity_eligible() to go side-ways and claim nothing is eligible. Thus limit the range of vlag accordingly. All this was quite rare, but fatal when it does happen.

In the Linux kernel, the following vulnerability has been resolved: gso: fix udp gso fraglist segmentation after pull from frag_list Detect gso fraglist skbs with corrupted geometry (see below) and pass these to skb_segment instead of skb_segment_list, as the first can segment them correctly. Valid SKB_GSO_FRAGLIST skbs - consist of two or more segments - the head_skb holds the protocol headers plus first gso_size - one or more frag_list skbs hold exactly one segment - all but the last must be gso_size Optional datapath hooks such as NAT and BPF (bpf_skb_pull_data) can modify these skbs, breaking these invariants. In extreme cases they pull all data into skb linear. For UDP, this causes a NULL ptr deref in __udpv4_gso_segment_list_csum at udp_hdr(seg->next)->dest. Detect invalid geometry due to pull, by checking head_skb size. Don't just drop, as this may blackhole a destination. Convert to be able to pass to regular skb_segment.

In the Linux kernel, the following vulnerability has been resolved: net: core: reject skb_copy(_expand) for fraglist GSO skbs SKB_GSO_FRAGLIST skbs must not be linearized, otherwise they become invalid. Return NULL if such an skb is passed to skb_copy or skb_copy_expand, in order to prevent a crash on a potential later call to skb_gso_segment.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: qca: fix NULL-deref on non-serdev suspend Qualcomm ROME controllers can be registered from the Bluetooth line discipline and in this case the HCI UART serdev pointer is NULL. Add the missing sanity check to prevent a NULL-pointer dereference when wakeup() is called for a non-serdev controller during suspend. Just return true for now to restore the original behaviour and address the crash with pre-6.2 kernels, which do not have commit e9b3e5b8c657 ("Bluetooth: hci_qca: only assign wakeup with serial port support") that causes the crash to happen already at setup() time.

In the Linux kernel, the following vulnerability has been resolved: ipv4: check for NULL idev in ip_route_use_hint() syzbot was able to trigger a NULL deref in fib_validate_source() in an old tree [1]. It appears the bug exists in latest trees. All calls to __in_dev_get_rcu() must be checked for a NULL result. [1] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 2 PID: 3257 Comm: syz-executor.3 Not tainted 5.10.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:fib_validate_source+0xbf/0x15a0 net/ipv4/fib_frontend.c:425 Code: 18 f2 f2 f2 f2 42 c7 44 20 23 f3 f3 f3 f3 48 89 44 24 78 42 c6 44 20 27 f3 e8 5d 88 48 fc 4c 89 e8 48 c1 e8 03 48 89 44 24 18 <42> 80 3c 20 00 74 08 4c 89 ef e8 d2 15 98 fc 48 89 5c 24 10 41 bf RSP: 0018:ffffc900015fee40 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88800f7a4000 RCX: ffff88800f4f90c0 RDX: 0000000000000000 RSI: 0000000004001eac RDI: ffff8880160c64c0 RBP: ffffc900015ff060 R08: 0000000000000000 R09: ffff88800f7a4000 R10: 0000000000000002 R11: ffff88800f4f90c0 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88800f7a4000 FS: 00007f938acfe6c0(0000) GS:ffff888058c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f938acddd58 CR3: 000000001248e000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip_route_use_hint+0x410/0x9b0 net/ipv4/route.c:2231 ip_rcv_finish_core+0x2c4/0x1a30 net/ipv4/ip_input.c:327 ip_list_rcv_finish net/ipv4/ip_input.c:612 [inline] ip_sublist_rcv+0x3ed/0xe50 net/ipv4/ip_input.c:638 ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:673 __netif_receive_skb_list_ptype net/core/dev.c:5572 [inline] __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5620 __netif_receive_skb_list net/core/dev.c:5672 [inline] netif_receive_skb_list_internal+0x9f9/0xdc0 net/core/dev.c:5764 netif_receive_skb_list+0x55/0x3e0 net/core/dev.c:5816 xdp_recv_frames net/bpf/test_run.c:257 [inline] xdp_test_run_batch net/bpf/test_run.c:335 [inline] bpf_test_run_xdp_live+0x1818/0x1d00 net/bpf/test_run.c:363 bpf_prog_test_run_xdp+0x81f/0x1170 net/bpf/test_run.c:1376 bpf_prog_test_run+0x349/0x3c0 kernel/bpf/syscall.c:3736 __sys_bpf+0x45c/0x710 kernel/bpf/syscall.c:5115 __do_sys_bpf kernel/bpf/syscall.c:5201 [inline] __se_sys_bpf kernel/bpf/syscall.c:5199 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5199

In the Linux kernel, the following vulnerability has been resolved: Julia Lawall reported this null pointer dereference, this should fix it.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Atom Integrated System Info v2_2 for DCN35 New request from KMD/VBIOS in order to support new UMA carveout model. This fixes a null dereference from accessing Ctx->dc_bios->integrated_info while it was NULL. DAL parses through the BIOS and extracts the necessary integrated_info but was missing a case for the new BIOS version 2.3.

In the Linux kernel, the following vulnerability has been resolved: null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues' Writing 'power' and 'submit_queues' concurrently will trigger kernel panic: Test script: modprobe null_blk nr_devices=0 mkdir -p /sys/kernel/config/nullb/nullb0 while true; do echo 1 > submit_queues; echo 4 > submit_queues; done & while true; do echo 1 > power; echo 0 > power; done Test result: BUG: kernel NULL pointer dereference, address: 0000000000000148 Oops: 0000 [#1] PREEMPT SMP RIP: 0010:__lock_acquire+0x41d/0x28f0 Call Trace: <TASK> lock_acquire+0x121/0x450 down_write+0x5f/0x1d0 simple_recursive_removal+0x12f/0x5c0 blk_mq_debugfs_unregister_hctxs+0x7c/0x100 blk_mq_update_nr_hw_queues+0x4a3/0x720 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk] nullb_device_submit_queues_store+0x79/0xf0 [null_blk] configfs_write_iter+0x119/0x1e0 vfs_write+0x326/0x730 ksys_write+0x74/0x150 This is because del_gendisk() can concurrent with blk_mq_update_nr_hw_queues(): nullb_device_power_store nullb_apply_submit_queues null_del_dev del_gendisk nullb_update_nr_hw_queues if (!dev->nullb) // still set while gendisk is deleted return 0 blk_mq_update_nr_hw_queues dev->nullb = NULL Fix this problem by resuing the global mutex to protect nullb_device_power_store() and nullb_update_nr_hw_queues() from configfs.

In the Linux kernel, the following vulnerability has been resolved: tls: fix missing memory barrier in tls_init In tls_init(), a write memory barrier is missing, and store-store reordering may cause NULL dereference in tls_{setsockopt,getsockopt}. CPU0 CPU1 ----- ----- // In tls_init() // In tls_ctx_create() ctx = kzalloc() ctx->sk_proto = READ_ONCE(sk->sk_prot) -(1) // In update_sk_prot() WRITE_ONCE(sk->sk_prot, tls_prots) -(2) // In sock_common_setsockopt() READ_ONCE(sk->sk_prot)->setsockopt() // In tls_{setsockopt,getsockopt}() ctx->sk_proto->setsockopt() -(3) In the above scenario, when (1) and (2) are reordered, (3) can observe the NULL value of ctx->sk_proto, causing NULL dereference. To fix it, we rely on rcu_assign_pointer() which implies the release barrier semantic. By moving rcu_assign_pointer() after ctx->sk_proto is initialized, we can ensure that ctx->sk_proto are visible when changing sk->sk_prot.

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-v2: Check for non-NULL vCPU in vgic_v2_parse_attr() vgic_v2_parse_attr() is responsible for finding the vCPU that matches the user-provided CPUID, which (of course) may not be valid. If the ID is invalid, kvm_get_vcpu_by_id() returns NULL, which isn't handled gracefully. Similar to the GICv3 uaccess flow, check that kvm_get_vcpu_by_id() actually returns something and fail the ioctl if not.

In the Linux kernel, the following vulnerability has been resolved: s390/bpf: Fix bpf_plt pointer arithmetic Kui-Feng Lee reported a crash on s390x triggered by the dummy_st_ops/dummy_init_ptr_arg test [1]: [<0000000000000002>] 0x2 [<00000000009d5cde>] bpf_struct_ops_test_run+0x156/0x250 [<000000000033145a>] __sys_bpf+0xa1a/0xd00 [<00000000003319dc>] __s390x_sys_bpf+0x44/0x50 [<0000000000c4382c>] __do_syscall+0x244/0x300 [<0000000000c59a40>] system_call+0x70/0x98 This is caused by GCC moving memcpy() after assignments in bpf_jit_plt(), resulting in NULL pointers being written instead of the return and the target addresses. Looking at the GCC internals, the reordering is allowed because the alias analysis thinks that the memcpy() destination and the assignments' left-hand-sides are based on different objects: new_plt and bpf_plt_ret/bpf_plt_target respectively, and therefore they cannot alias. This is in turn due to a violation of the C standard: When two pointers are subtracted, both shall point to elements of the same array object, or one past the last element of the array object ... From the C's perspective, bpf_plt_ret and bpf_plt are distinct objects and cannot be subtracted. In the practical terms, doing so confuses the GCC's alias analysis. The code was written this way in order to let the C side know a few offsets defined in the assembly. While nice, this is by no means necessary. Fix the noncompliance by hardcoding these offsets. [1] https://lore.kernel.org/bpf/c9923c1d-971d-4022-8dc8-1364e929d34c@gmail.com/

In the Linux kernel, the following vulnerability has been resolved: selinux: avoid dereference of garbage after mount failure In case kern_mount() fails and returns an error pointer return in the error branch instead of continuing and dereferencing the error pointer. While on it drop the never read static variable selinuxfs_mount.

In the Linux kernel, the following vulnerability has been resolved: net: nexthop: fix null pointer dereference when IPv6 is not enabled When we try to add an IPv6 nexthop and IPv6 is not enabled (!CONFIG_IPV6) we'll hit a NULL pointer dereference[1] in the error path of nh_create_ipv6() due to calling ipv6_stub->fib6_nh_release. The bug has been present since the beginning of IPv6 nexthop gateway support. Commit 1aefd3de7bc6 ("ipv6: Add fib6_nh_init and release to stubs") tells us that only fib6_nh_init has a dummy stub because fib6_nh_release should not be called if fib6_nh_init returns an error, but the commit below added a call to ipv6_stub->fib6_nh_release in its error path. To fix it return the dummy stub's -EAFNOSUPPORT error directly without calling ipv6_stub->fib6_nh_release in nh_create_ipv6()'s error path. [1] Output is a bit truncated, but it clearly shows the error. BUG: kernel NULL pointer dereference, address: 000000000000000000 #PF: supervisor instruction fetch in kernel modede #PF: error_code(0x0010) - not-present pagege PGD 0 P4D 0 Oops: 0010 [#1] PREEMPT SMP NOPTI CPU: 4 PID: 638 Comm: ip Kdump: loaded Not tainted 5.16.0-rc1+ #446 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffff888109f5b8f0 EFLAGS: 00010286^Ac RAX: 0000000000000000 RBX: ffff888109f5ba28 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881008a2860 RBP: ffff888109f5b9d8 R08: 0000000000000000 R09: 0000000000000000 R10: ffff888109f5b978 R11: ffff888109f5b948 R12: 00000000ffffff9f R13: ffff8881008a2a80 R14: ffff8881008a2860 R15: ffff8881008a2840 FS: 00007f98de70f100(0000) GS:ffff88822bf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000100efc000 CR4: 00000000000006e0 Call Trace: <TASK> nh_create_ipv6+0xed/0x10c rtm_new_nexthop+0x6d7/0x13f3 ? check_preemption_disabled+0x3d/0xf2 ? lock_is_held_type+0xbe/0xfd rtnetlink_rcv_msg+0x23f/0x26a ? check_preemption_disabled+0x3d/0xf2 ? rtnl_calcit.isra.0+0x147/0x147 netlink_rcv_skb+0x61/0xb2 netlink_unicast+0x100/0x187 netlink_sendmsg+0x37f/0x3a0 ? netlink_unicast+0x187/0x187 sock_sendmsg_nosec+0x67/0x9b ____sys_sendmsg+0x19d/0x1f9 ? copy_msghdr_from_user+0x4c/0x5e ? rcu_read_lock_any_held+0x2a/0x78 ___sys_sendmsg+0x6c/0x8c ? asm_sysvec_apic_timer_interrupt+0x12/0x20 ? lockdep_hardirqs_on+0xd9/0x102 ? sockfd_lookup_light+0x69/0x99 __sys_sendmsg+0x50/0x6e do_syscall_64+0xcb/0xf2 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f98dea28914 Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 48 8d 05 e9 5d 0c 00 8b 00 85 c0 75 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 41 89 d4 55 48 89 f5 53 RSP: 002b:00007fff859f5e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e2e RAX: ffffffffffffffda RBX: 00000000619cb810 RCX: 00007f98dea28914 RDX: 0000000000000000 RSI: 00007fff859f5ed0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000008 R10: fffffffffffffce6 R11: 0000000000000246 R12: 0000000000000001 R13: 000055c0097ae520 R14: 000055c0097957fd R15: 00007fff859f63a0 </TASK> Modules linked in: bridge stp llc bonding virtio_net

In the Linux kernel, the following vulnerability has been resolved: wifi: rtw89: fix null pointer access when abort scan During cancel scan we might use vif that weren't scanning. Fix this by using the actual scanning vif.

In the Linux kernel, the following vulnerability has been resolved: pmdomain: ti: Add a null pointer check to the omap_prm_domain_init 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: Bluetooth: HCI: Fix potential null-ptr-deref Fix potential null-ptr-deref in hci_le_big_sync_established_evt().

In the Linux kernel, the following vulnerability has been resolved: aio: Fix null ptr deref in aio_complete() wakeup list_del_init_careful() needs to be the last access to the wait queue entry - it effectively unlocks access. Previously, finish_wait() would see the empty list head and skip taking the lock, and then we'd return - but the completion path would still attempt to do the wakeup after the task_struct pointer had been overwritten.

In the Linux kernel, the following vulnerability has been resolved: swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y Using restricted DMA pools (CONFIG_DMA_RESTRICTED_POOL=y) in conjunction with dynamic SWIOTLB (CONFIG_SWIOTLB_DYNAMIC=y) leads to the following crash when initialising the restricted pools at boot-time: | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 | Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP | pc : rmem_swiotlb_device_init+0xfc/0x1ec | lr : rmem_swiotlb_device_init+0xf0/0x1ec | Call trace: | rmem_swiotlb_device_init+0xfc/0x1ec | of_reserved_mem_device_init_by_idx+0x18c/0x238 | of_dma_configure_id+0x31c/0x33c | platform_dma_configure+0x34/0x80 faddr2line reveals that the crash is in the list validation code: include/linux/list.h:83 include/linux/rculist.h:79 include/linux/rculist.h:106 kernel/dma/swiotlb.c:306 kernel/dma/swiotlb.c:1695 because add_mem_pool() is trying to list_add_rcu() to a NULL 'mem->pools'. Fix the crash by initialising the 'mem->pools' list_head in rmem_swiotlb_device_init() before calling add_mem_pool().

In the Linux kernel, the following vulnerability has been resolved: drm/arm/malidp: fix a possible null pointer dereference In malidp_mw_connector_reset, new memory is allocated with kzalloc, but no check is performed. In order to prevent null pointer dereferencing, ensure that mw_state is checked before calling __drm_atomic_helper_connector_reset.

In the Linux kernel, the following vulnerability has been resolved: fpga: manager: add owner module and take its refcount The current implementation of the fpga manager 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 manager if the parent device does not have a driver. To address this problem, add a module owner pointer to the fpga_manager struct and use it to take the module's refcount. Modify the functions for registering the manager 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 manager as the owner. This ensures compatibility with existing low-level control modules and reduces the chances of registering a manager without setting the owner. Also, update the documentation to keep it consistent with the new interface for registering an fpga manager. Other changes: opportunistically move put_device() from __fpga_mgr_get() to fpga_mgr_get() and of_fpga_mgr_get() to improve code clarity since the manager device is taken in these functions.

In the Linux kernel, the following vulnerability has been resolved: maple_tree: fix mas_empty_area_rev() null pointer dereference Currently the code calls mas_start() followed by mas_data_end() if the maple state is MA_START, but mas_start() may return with the maple state node == NULL. This will lead to a null pointer dereference when checking information in the NULL node, which is done in mas_data_end(). Avoid setting the offset if there is no node by waiting until after the maple state is checked for an empty or single entry state. A user could trigger the events to cause a kernel oops by unmapping all vmas to produce an empty maple tree, then mapping a vma that would cause the scenario described above.

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: bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue Fix NULL pointer data-races in sk_psock_skb_ingress_enqueue() which syzbot reported [1]. [1] BUG: KCSAN: data-race in sk_psock_drop / sk_psock_skb_ingress_enqueue write to 0xffff88814b3278b8 of 8 bytes by task 10724 on cpu 1: sk_psock_stop_verdict net/core/skmsg.c:1257 [inline] sk_psock_drop+0x13e/0x1f0 net/core/skmsg.c:843 sk_psock_put include/linux/skmsg.h:459 [inline] sock_map_close+0x1a7/0x260 net/core/sock_map.c:1648 unix_release+0x4b/0x80 net/unix/af_unix.c:1048 __sock_release net/socket.c:659 [inline] sock_close+0x68/0x150 net/socket.c:1421 __fput+0x2c1/0x660 fs/file_table.c:422 __fput_sync+0x44/0x60 fs/file_table.c:507 __do_sys_close fs/open.c:1556 [inline] __se_sys_close+0x101/0x1b0 fs/open.c:1541 __x64_sys_close+0x1f/0x30 fs/open.c:1541 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 read to 0xffff88814b3278b8 of 8 bytes by task 10713 on cpu 0: sk_psock_data_ready include/linux/skmsg.h:464 [inline] sk_psock_skb_ingress_enqueue+0x32d/0x390 net/core/skmsg.c:555 sk_psock_skb_ingress_self+0x185/0x1e0 net/core/skmsg.c:606 sk_psock_verdict_apply net/core/skmsg.c:1008 [inline] sk_psock_verdict_recv+0x3e4/0x4a0 net/core/skmsg.c:1202 unix_read_skb net/unix/af_unix.c:2546 [inline] unix_stream_read_skb+0x9e/0xf0 net/unix/af_unix.c:2682 sk_psock_verdict_data_ready+0x77/0x220 net/core/skmsg.c:1223 unix_stream_sendmsg+0x527/0x860 net/unix/af_unix.c:2339 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x140/0x180 net/socket.c:745 ____sys_sendmsg+0x312/0x410 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x1e9/0x280 net/socket.c:2667 __do_sys_sendmsg net/socket.c:2676 [inline] __se_sys_sendmsg net/socket.c:2674 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 value changed: 0xffffffff83d7feb0 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10713 Comm: syz-executor.4 Tainted: G W 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Prior to this, commit 4cd12c6065df ("bpf, sockmap: Fix NULL pointer dereference in sk_psock_verdict_data_ready()") fixed one NULL pointer similarly due to no protection of saved_data_ready. Here is another different caller causing the same issue because of the same reason. So we should protect it with sk_callback_lock read lock because the writer side in the sk_psock_drop() uses "write_lock_bh(&sk->sk_callback_lock);". To avoid errors that could happen in future, I move those two pairs of lock into the sk_psock_data_ready(), which is suggested by John Fastabend.

In the Linux kernel, the following vulnerability has been resolved: wifi: nl80211: don't free NULL coalescing rule If the parsing fails, we can dereference a NULL pointer here.

In the Linux kernel, the following vulnerability has been resolved: usb: typec: tcpm: Check for port partner validity before consuming it typec_register_partner() does not guarantee partner registration to always succeed. In the event of failure, port->partner is set to the error value or NULL. Given that port->partner validity is not checked, this results in the following crash: Unable to handle kernel NULL pointer dereference at virtual address xx pc : run_state_machine+0x1bc8/0x1c08 lr : run_state_machine+0x1b90/0x1c08 .. Call trace: run_state_machine+0x1bc8/0x1c08 tcpm_state_machine_work+0x94/0xe4 kthread_worker_fn+0x118/0x328 kthread+0x1d0/0x23c ret_from_fork+0x10/0x20 To prevent the crash, check for port->partner validity before derefencing it in all the call sites.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btintel: Fix null ptr deref in btintel_read_version If hci_cmd_sync_complete() is triggered and skb is NULL, then hdev->req_skb is NULL, which will cause this issue.

In the Linux kernel, the following vulnerability has been resolved: netfilter: tproxy: bail out if IP has been disabled on the device syzbot reports: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] [..] RIP: 0010:nf_tproxy_laddr4+0xb7/0x340 net/ipv4/netfilter/nf_tproxy_ipv4.c:62 Call Trace: nft_tproxy_eval_v4 net/netfilter/nft_tproxy.c:56 [inline] nft_tproxy_eval+0xa9a/0x1a00 net/netfilter/nft_tproxy.c:168 __in_dev_get_rcu() can return NULL, so check for this.

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: net/mlx5: Use mlx5_ipsec_rx_status_destroy to correctly delete status rules rx_create no longer allocates a modify_hdr instance that needs to be cleaned up. The mlx5_modify_header_dealloc call will lead to a NULL pointer dereference. A leak in the rules also previously occurred since there are now two rules populated related to status. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 109907067 P4D 109907067 PUD 116890067 PMD 0 Oops: 0000 [#1] SMP CPU: 1 PID: 484 Comm: ip Not tainted 6.9.0-rc2-rrameshbabu+ #254 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Arch Linux 1.16.3-1-1 04/01/2014 RIP: 0010:mlx5_modify_header_dealloc+0xd/0x70 <snip> Call Trace: <TASK> ? show_regs+0x60/0x70 ? __die+0x24/0x70 ? page_fault_oops+0x15f/0x430 ? free_to_partial_list.constprop.0+0x79/0x150 ? do_user_addr_fault+0x2c9/0x5c0 ? exc_page_fault+0x63/0x110 ? asm_exc_page_fault+0x27/0x30 ? mlx5_modify_header_dealloc+0xd/0x70 rx_create+0x374/0x590 rx_add_rule+0x3ad/0x500 ? rx_add_rule+0x3ad/0x500 ? mlx5_cmd_exec+0x2c/0x40 ? mlx5_create_ipsec_obj+0xd6/0x200 mlx5e_accel_ipsec_fs_add_rule+0x31/0xf0 mlx5e_xfrm_add_state+0x426/0xc00 <snip>

In the Linux kernel, the following vulnerability has been resolved: ASoC: mediatek: sof-common: Add NULL check for normal_link string It's not granted that all entries of struct sof_conn_stream declare a `normal_link` (a non-SOF, direct link) string, and this is the case for SoCs that support only SOF paths (hence do not support both direct and SOF usecases). For example, in the case of MT8188 there is no normal_link string in any of the sof_conn_stream entries and there will be more drivers doing that in the future. To avoid possible NULL pointer KPs, add a NULL check for `normal_link`.

In the Linux kernel, the following vulnerability has been resolved: mm/slub: avoid zeroing outside-object freepointer for single free Commit 284f17ac13fe ("mm/slub: handle bulk and single object freeing separately") splits single and bulk object freeing in two functions slab_free() and slab_free_bulk() which leads slab_free() to call slab_free_hook() directly instead of slab_free_freelist_hook(). If `init_on_free` is set, slab_free_hook() zeroes the object. Afterward, if `slub_debug=F` and `CONFIG_SLAB_FREELIST_HARDENED` are set, the do_slab_free() slowpath executes freelist consistency checks and try to decode a zeroed freepointer which leads to a "Freepointer corrupt" detection in check_object(). During bulk free, slab_free_freelist_hook() isn't affected as it always sets it objects freepointer using set_freepointer() to maintain its reconstructed freelist after `init_on_free`. For single free, object's freepointer thus needs to be avoided when stored outside the object if `init_on_free` is set. The freepointer left as is, check_object() may later detect an invalid pointer value due to objects overflow. To reproduce, set `slub_debug=FU init_on_free=1 log_level=7` on the command line of a kernel build with `CONFIG_SLAB_FREELIST_HARDENED=y`. dmesg sample log: [ 10.708715] ============================================================================= [ 10.710323] BUG kmalloc-rnd-05-32 (Tainted: G B T ): Freepointer corrupt [ 10.712695] ----------------------------------------------------------------------------- [ 10.712695] [ 10.712695] Slab 0xffffd8bdc400d580 objects=32 used=4 fp=0xffff9d9a80356f80 flags=0x200000000000a00(workingset|slab|node=0|zone=2) [ 10.716698] Object 0xffff9d9a80356600 @offset=1536 fp=0x7ee4f480ce0ecd7c [ 10.716698] [ 10.716698] Bytes b4 ffff9d9a803565f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.720703] Object ffff9d9a80356600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.720703] Object ffff9d9a80356610: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.724696] Padding ffff9d9a8035666c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 10.724696] Padding ffff9d9a8035667c: 00 00 00 00 .... [ 10.724696] FIX kmalloc-rnd-05-32: Object at 0xffff9d9a80356600 not freed

In the Linux kernel, the following vulnerability has been resolved: xdp: use flags field to disambiguate broadcast redirect When redirecting a packet using XDP, the bpf_redirect_map() helper will set up the redirect destination information in struct bpf_redirect_info (using the __bpf_xdp_redirect_map() helper function), and the xdp_do_redirect() function will read this information after the XDP program returns and pass the frame on to the right redirect destination. When using the BPF_F_BROADCAST flag to do multicast redirect to a whole map, __bpf_xdp_redirect_map() sets the 'map' pointer in struct bpf_redirect_info to point to the destination map to be broadcast. And xdp_do_redirect() reacts to the value of this map pointer to decide whether it's dealing with a broadcast or a single-value redirect. However, if the destination map is being destroyed before xdp_do_redirect() is called, the map pointer will be cleared out (by bpf_clear_redirect_map()) without waiting for any XDP programs to stop running. This causes xdp_do_redirect() to think that the redirect was to a single target, but the target pointer is also NULL (since broadcast redirects don't have a single target), so this causes a crash when a NULL pointer is passed to dev_map_enqueue(). To fix this, change xdp_do_redirect() to react directly to the presence of the BPF_F_BROADCAST flag in the 'flags' value in struct bpf_redirect_info to disambiguate between a single-target and a broadcast redirect. And only read the 'map' pointer if the broadcast flag is set, aborting if that has been cleared out in the meantime. This prevents the crash, while keeping the atomic (cmpxchg-based) clearing of the map pointer itself, and without adding any more checks in the non-broadcast fast path.

K7RKScan.sys in K7 Ultimate Security before 17.0.2019 allows local users to cause a denial of service (BSOD) because of a NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries/iommu: LPAR panics during boot up with a frozen PE At the time of LPAR boot up, partition firmware provides Open Firmware property ibm,dma-window for the PE. This property is provided on the PCI bus the PE is attached to. There are execptions where the partition firmware might not provide this property for the PE at the time of LPAR boot up. One of the scenario is where the firmware has frozen the PE due to some error condition. This PE is frozen for 24 hours or unless the whole system is reinitialized. Within this time frame, if the LPAR is booted, the frozen PE will be presented to the LPAR but ibm,dma-window property could be missing. Today, under these circumstances, the LPAR oopses with NULL pointer dereference, when configuring the PCI bus the PE is attached to. BUG: Kernel NULL pointer dereference on read at 0x000000c8 Faulting instruction address: 0xc0000000001024c0 Oops: Kernel access of bad area, sig: 7 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: Supported: Yes CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.4.0-150600.9-default #1 Hardware name: IBM,9043-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_023) hv:phyp pSeries NIP: c0000000001024c0 LR: c0000000001024b0 CTR: c000000000102450 REGS: c0000000037db5c0 TRAP: 0300 Not tainted (6.4.0-150600.9-default) MSR: 8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 28000822 XER: 00000000 CFAR: c00000000010254c DAR: 00000000000000c8 DSISR: 00080000 IRQMASK: 0 ... NIP [c0000000001024c0] pci_dma_bus_setup_pSeriesLP+0x70/0x2a0 LR [c0000000001024b0] pci_dma_bus_setup_pSeriesLP+0x60/0x2a0 Call Trace: pci_dma_bus_setup_pSeriesLP+0x60/0x2a0 (unreliable) pcibios_setup_bus_self+0x1c0/0x370 __of_scan_bus+0x2f8/0x330 pcibios_scan_phb+0x280/0x3d0 pcibios_init+0x88/0x12c do_one_initcall+0x60/0x320 kernel_init_freeable+0x344/0x3e4 kernel_init+0x34/0x1d0 ret_from_kernel_user_thread+0x14/0x1c