In the Linux kernel, the following vulnerability has been resolved: ext4: add reserved GDT blocks check We capture a NULL pointer issue when resizing a corrupt ext4 image which is freshly clear resize_inode feature (not run e2fsck). It could be simply reproduced by following steps. The problem is because of the resize_inode feature was cleared, and it will convert the filesystem to meta_bg mode in ext4_resize_fs(), but the es->s_reserved_gdt_blocks was not reduced to zero, so could we mistakenly call reserve_backup_gdb() and passing an uninitialized resize_inode to it when adding new group descriptors. mkfs.ext4 /dev/sda 3G tune2fs -O ^resize_inode /dev/sda #forget to run requested e2fsck mount /dev/sda /mnt resize2fs /dev/sda 8G ======== BUG: kernel NULL pointer dereference, address: 0000000000000028 CPU: 19 PID: 3243 Comm: resize2fs Not tainted 5.18.0-rc7-00001-gfde086c5ebfd #748 ... RIP: 0010:ext4_flex_group_add+0xe08/0x2570 ... Call Trace: <TASK> ext4_resize_fs+0xbec/0x1660 __ext4_ioctl+0x1749/0x24e0 ext4_ioctl+0x12/0x20 __x64_sys_ioctl+0xa6/0x110 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2dd739617b ======== The fix is simple, add a check in ext4_resize_begin() to make sure that the es->s_reserved_gdt_blocks is zero when the resize_inode feature is disabled.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/mdp5: Return error code in mdp5_mixer_release when deadlock is detected There is a possibility for mdp5_get_global_state to return -EDEADLK when acquiring the modeset lock, but currently global_state in mdp5_mixer_release doesn't check for if an error is returned. To avoid a NULL dereference error, let's have mdp5_mixer_release check if an error is returned and propagate that error. Patchwork: https://patchwork.freedesktop.org/patch/485181/

In the Linux kernel, the following vulnerability has been resolved: kernfs: fix potential NULL dereference in __kernfs_remove When lockdep is enabled, lockdep_assert_held_write would cause potential NULL pointer dereference. Fix the following smatch warnings: fs/kernfs/dir.c:1353 __kernfs_remove() warn: variable dereferenced before check 'kn' (see line 1346)

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

In the Linux kernel, the following vulnerability has been resolved: BPF: Fix potential bad pointer dereference in bpf_sys_bpf() The bpf_sys_bpf() helper function allows an eBPF program to load another eBPF program from within the kernel. In this case the argument union bpf_attr pointer (as well as the insns and license pointers inside) is a kernel address instead of a userspace address (which is the case of a usual bpf() syscall). To make the memory copying process in the syscall work in both cases, bpfptr_t was introduced to wrap around the pointer and distinguish its origin. Specifically, when copying memory contents from a bpfptr_t, a copy_from_user() is performed in case of a userspace address and a memcpy() is performed for a kernel address. This can lead to problems because the in-kernel pointer is never checked for validity. The problem happens when an eBPF syscall program tries to call bpf_sys_bpf() to load a program but provides a bad insns pointer -- say 0xdeadbeef -- in the bpf_attr union. The helper calls __sys_bpf() which would then call bpf_prog_load() to load the program. bpf_prog_load() is responsible for copying the eBPF instructions to the newly allocated memory for the program; it creates a kernel bpfptr_t for insns and invokes copy_from_bpfptr(). Internally, all bpfptr_t operations are backed by the corresponding sockptr_t operations, which performs direct memcpy() on kernel pointers for copy_from/strncpy_from operations. Therefore, the code is always happy to dereference the bad pointer to trigger a un-handle-able page fault and in turn an oops. However, this is not supposed to happen because at that point the eBPF program is already verified and should not cause a memory error. Sample KASAN trace: [ 25.685056][ T228] ================================================================== [ 25.685680][ T228] BUG: KASAN: user-memory-access in copy_from_bpfptr+0x21/0x30 [ 25.686210][ T228] Read of size 80 at addr 00000000deadbeef by task poc/228 [ 25.686732][ T228] [ 25.686893][ T228] CPU: 3 PID: 228 Comm: poc Not tainted 5.19.0-rc7 #7 [ 25.687375][ T228] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS d55cb5a 04/01/2014 [ 25.687991][ T228] Call Trace: [ 25.688223][ T228] <TASK> [ 25.688429][ T228] dump_stack_lvl+0x73/0x9e [ 25.688747][ T228] print_report+0xea/0x200 [ 25.689061][ T228] ? copy_from_bpfptr+0x21/0x30 [ 25.689401][ T228] ? _printk+0x54/0x6e [ 25.689693][ T228] ? _raw_spin_lock_irqsave+0x70/0xd0 [ 25.690071][ T228] ? copy_from_bpfptr+0x21/0x30 [ 25.690412][ T228] kasan_report+0xb5/0xe0 [ 25.690716][ T228] ? copy_from_bpfptr+0x21/0x30 [ 25.691059][ T228] kasan_check_range+0x2bd/0x2e0 [ 25.691405][ T228] ? copy_from_bpfptr+0x21/0x30 [ 25.691734][ T228] memcpy+0x25/0x60 [ 25.692000][ T228] copy_from_bpfptr+0x21/0x30 [ 25.692328][ T228] bpf_prog_load+0x604/0x9e0 [ 25.692653][ T228] ? cap_capable+0xb4/0xe0 [ 25.692956][ T228] ? security_capable+0x4f/0x70 [ 25.693324][ T228] __sys_bpf+0x3af/0x580 [ 25.693635][ T228] bpf_sys_bpf+0x45/0x240 [ 25.693937][ T228] bpf_prog_f0ec79a5a3caca46_bpf_func1+0xa2/0xbd [ 25.694394][ T228] bpf_prog_run_pin_on_cpu+0x2f/0xb0 [ 25.694756][ T228] bpf_prog_test_run_syscall+0x146/0x1c0 [ 25.695144][ T228] bpf_prog_test_run+0x172/0x190 [ 25.695487][ T228] __sys_bpf+0x2c5/0x580 [ 25.695776][ T228] __x64_sys_bpf+0x3a/0x50 [ 25.696084][ T228] do_syscall_64+0x60/0x90 [ 25.696393][ T228] ? fpregs_assert_state_consistent+0x50/0x60 [ 25.696815][ T228] ? exit_to_user_mode_prepare+0x36/0xa0 [ 25.697202][ T228] ? syscall_exit_to_user_mode+0x20/0x40 [ 25.697586][ T228] ? do_syscall_64+0x6e/0x90 [ 25.697899][ T228] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 25.698312][ T228] RIP: 0033:0x7f6d543fb759 [ 25.698624][ T228] Code: 08 5b 89 e8 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d ---truncated---

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Do _all_ initialization before exposing /dev/kvm to userspace Call kvm_init() only after _all_ setup is complete, as kvm_init() exposes /dev/kvm to userspace and thus allows userspace to create VMs (and call other ioctls). E.g. KVM will encounter a NULL pointer when attempting to add a vCPU to the per-CPU loaded_vmcss_on_cpu list if userspace is able to create a VM before vmx_init() configures said list. BUG: kernel NULL pointer dereference, address: 0000000000000008 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP CPU: 6 PID: 1143 Comm: stable Not tainted 6.0.0-rc7+ #988 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:vmx_vcpu_load_vmcs+0x68/0x230 [kvm_intel] <TASK> vmx_vcpu_load+0x16/0x60 [kvm_intel] kvm_arch_vcpu_load+0x32/0x1f0 [kvm] vcpu_load+0x2f/0x40 [kvm] kvm_arch_vcpu_create+0x231/0x310 [kvm] kvm_vm_ioctl+0x79f/0xe10 [kvm] ? handle_mm_fault+0xb1/0x220 __x64_sys_ioctl+0x80/0xb0 do_syscall_64+0x2b/0x50 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f5a6b05743b </TASK> Modules linked in: vhost_net vhost vhost_iotlb tap kvm_intel(+) kvm irqbypass

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mv88e6060: prevent crash on an unused port If the port isn't a CPU port nor a user port, 'cpu_dp' is a null pointer and a crash happened on dereferencing it in mv88e6060_setup_port(): [ 9.575872] Unable to handle kernel NULL pointer dereference at virtual address 00000014 ... [ 9.942216] mv88e6060_setup from dsa_register_switch+0x814/0xe84 [ 9.948616] dsa_register_switch from mdio_probe+0x2c/0x54 [ 9.954433] mdio_probe from really_probe.part.0+0x98/0x2a0 [ 9.960375] really_probe.part.0 from driver_probe_device+0x30/0x10c [ 9.967029] driver_probe_device from __device_attach_driver+0xb8/0x13c [ 9.973946] __device_attach_driver from bus_for_each_drv+0x90/0xe0 [ 9.980509] bus_for_each_drv from __device_attach+0x110/0x184 [ 9.986632] __device_attach from bus_probe_device+0x8c/0x94 [ 9.992577] bus_probe_device from deferred_probe_work_func+0x78/0xa8 [ 9.999311] deferred_probe_work_func from process_one_work+0x290/0x73c [ 10.006292] process_one_work from worker_thread+0x30/0x4b8 [ 10.012155] worker_thread from kthread+0xd4/0x10c [ 10.017238] kthread from ret_from_fork+0x14/0x3c

In the Linux kernel, the following vulnerability has been resolved: skmsg: Fix wrong last sg check in sk_msg_recvmsg() Fix one kernel NULL pointer dereference as below: [ 224.462334] Call Trace: [ 224.462394] __tcp_bpf_recvmsg+0xd3/0x380 [ 224.462441] ? sock_has_perm+0x78/0xa0 [ 224.462463] tcp_bpf_recvmsg+0x12e/0x220 [ 224.462494] inet_recvmsg+0x5b/0xd0 [ 224.462534] __sys_recvfrom+0xc8/0x130 [ 224.462574] ? syscall_trace_enter+0x1df/0x2e0 [ 224.462606] ? __do_page_fault+0x2de/0x500 [ 224.462635] __x64_sys_recvfrom+0x24/0x30 [ 224.462660] do_syscall_64+0x5d/0x1d0 [ 224.462709] entry_SYSCALL_64_after_hwframe+0x65/0xca In commit 9974d37ea75f ("skmsg: Fix invalid last sg check in sk_msg_recvmsg()"), we change last sg check to sg_is_last(), but in sockmap redirection case (without stream_parser/stream_verdict/ skb_verdict), we did not mark the end of the scatterlist. Check the sk_msg_alloc, sk_msg_page_add, and bpf_msg_push_data functions, they all do not mark the end of sg. They are expected to use sg.end for end judgment. So the judgment of '(i != msg_rx->sg.end)' is added back here.

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Check for null pointer of pointer substream before dereferencing it Pointer substream is being dereferenced on the assignment of pointer card before substream is being null checked with the macro PCM_RUNTIME_CHECK. Although PCM_RUNTIME_CHECK calls BUG_ON, it still is useful to perform the the pointer check before card is assigned.

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Fix missing i_op in ntfs_read_mft There is null pointer dereference because i_op == NULL. The bug happens because we don't initialize i_op for records in $Extend.

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

In the Linux kernel, the following vulnerability has been resolved: vdpa_sim_blk: set number of address spaces and virtqueue groups Commit bda324fd037a ("vdpasim: control virtqueue support") added two new fields (nas, ngroups) to vdpasim_dev_attr, but we forgot to initialize them for vdpa_sim_blk. When creating a new vdpa_sim_blk device this causes the kernel to panic in this way:    $ vdpa dev add mgmtdev vdpasim_blk name blk0    BUG: kernel NULL pointer dereference, address: 0000000000000030    ...    RIP: 0010:vhost_iotlb_add_range_ctx+0x41/0x220 [vhost_iotlb]    ...    Call Trace:     <TASK>     vhost_iotlb_add_range+0x11/0x800 [vhost_iotlb]     vdpasim_map_range+0x91/0xd0 [vdpa_sim]     vdpasim_alloc_coherent+0x56/0x90 [vdpa_sim]     ... This happens because vdpasim->iommu[0] is not initialized when dev_attr.nas is 0. Let's fix this issue by initializing both (nas, ngroups) to 1 for vdpa_sim_blk.

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: ASoC: qcom: Add checks for devm_kcalloc As the devm_kcalloc may return NULL, the return value needs to be checked to avoid NULL poineter dereference.

In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_transport_sas: Fix error handling in sas_phy_add() If transport_add_device() fails in sas_phy_add(), the kernel will crash trying to delete the device in transport_remove_device() called from sas_remove_host(). Unable to handle kernel NULL pointer dereference at virtual address 0000000000000108 CPU: 61 PID: 42829 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc1+ #173 pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : device_del+0x54/0x3d0 lr : device_del+0x37c/0x3d0 Call trace: device_del+0x54/0x3d0 attribute_container_class_device_del+0x28/0x38 transport_remove_classdev+0x6c/0x80 attribute_container_device_trigger+0x108/0x110 transport_remove_device+0x28/0x38 sas_phy_delete+0x30/0x60 [scsi_transport_sas] do_sas_phy_delete+0x6c/0x80 [scsi_transport_sas] device_for_each_child+0x68/0xb0 sas_remove_children+0x40/0x50 [scsi_transport_sas] sas_remove_host+0x20/0x38 [scsi_transport_sas] hisi_sas_remove+0x40/0x68 [hisi_sas_main] hisi_sas_v2_remove+0x20/0x30 [hisi_sas_v2_hw] platform_remove+0x2c/0x60 Fix this by checking and handling return value of transport_add_device() in sas_phy_add().

arch/powerpc/perf/core-book3s.c in the Linux kernel before 5.12.13, on systems with perf_event_paranoid=-1 and no specific PMU driver support registered, allows local users to cause a denial of service (perf_instruction_pointer NULL pointer dereference and OOPS) via a "perf record" command.

In the Linux kernel, the following vulnerability has been resolved: ACPI: processor: idle: Check acpi_fetch_acpi_dev() return value The return value of acpi_fetch_acpi_dev() could be NULL, which would cause a NULL pointer dereference to occur in acpi_device_hid(). [ rjw: Subject and changelog edits, added empty line after if () ]

In the Linux kernel, the following vulnerability has been resolved: drm: Fix potential null-ptr-deref in drm_vblank_destroy_worker() drm_vblank_init() call drmm_add_action_or_reset() with drm_vblank_init_release() as action. If __drmm_add_action() failed, will directly call drm_vblank_init_release() with the vblank whose worker is NULL. As the resule, a null-ptr-deref will happen in kthread_destroy_worker(). Add the NULL check before calling drm_vblank_destroy_worker(). BUG: null-ptr-deref KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f] CPU: 5 PID: 961 Comm: modprobe Not tainted 6.0.0-11331-gd465bff130bf-dirty RIP: 0010:kthread_destroy_worker+0x25/0xb0 Call Trace: <TASK> drm_vblank_init_release+0x124/0x220 [drm] ? drm_crtc_vblank_restore+0x8b0/0x8b0 [drm] __drmm_add_action_or_reset+0x41/0x50 [drm] drm_vblank_init+0x282/0x310 [drm] vkms_init+0x35f/0x1000 [vkms] ? 0xffffffffc4508000 ? lock_is_held_type+0xd7/0x130 ? __kmem_cache_alloc_node+0x1c2/0x2b0 ? lock_is_held_type+0xd7/0x130 ? 0xffffffffc4508000 do_one_initcall+0xd0/0x4f0 ... do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0

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

In the Linux kernel, the following vulnerability has been resolved: ASoC: DPCM: Don't pick up BE without substream When DPCM tries to add valid BE connections at dpcm_add_paths(), it doesn't check whether the picked BE actually supports for the given stream direction. Due to that, when an asymmetric BE stream is present, it picks up wrongly and this may result in a NULL dereference at a later point where the code assumes the existence of a corresponding BE substream. This patch adds the check for the presence of the substream for the target BE for avoiding the problem above. Note that we have already some fix for non-existing BE substream at commit 6246f283d5e0 ("ASoC: dpcm: skip missing substream while applying symmetry"). But the code path we've hit recently is rather happening before the previous fix. So this patch tries to fix at picking up a BE instead of parsing BE lists.

In the Linux kernel, the following vulnerability has been resolved: ata: libata-transport: fix error handling in ata_tdev_add() In ata_tdev_add(), the return value of transport_add_device() is not checked. As a result, it causes null-ptr-deref while removing the module, because transport_remove_device() is called to remove the device that was not added. Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0 CPU: 13 PID: 13603 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #36 pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : device_del+0x48/0x3a0 lr : device_del+0x44/0x3a0 Call trace: device_del+0x48/0x3a0 attribute_container_class_device_del+0x28/0x40 transport_remove_classdev+0x60/0x7c attribute_container_device_trigger+0x118/0x120 transport_remove_device+0x20/0x30 ata_tdev_delete+0x24/0x50 [libata] ata_tlink_delete+0x40/0xa0 [libata] ata_tport_delete+0x2c/0x60 [libata] ata_port_detach+0x148/0x1b0 [libata] ata_pci_remove_one+0x50/0x80 [libata] ahci_remove_one+0x4c/0x8c [ahci] Fix this by checking and handling return value of transport_add_device() in ata_tdev_add(). In the error path, device_del() is called to delete the device which was added earlier in this function, and ata_tdev_free() is called to free ata_dev.

In the Linux kernel, the following vulnerability has been resolved: ice: always check VF VSI pointer values The ice_get_vf_vsi function can return NULL in some cases, such as if handling messages during a reset where the VSI is being removed and recreated. Several places throughout the driver do not bother to check whether this VSI pointer is valid. Static analysis tools maybe report issues because they detect paths where a potentially NULL pointer could be dereferenced. Fix this by checking the return value of ice_get_vf_vsi everywhere.

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: fs/ntfs3: Validate BOOT record_size When the NTFS BOOT record_size field < 0, it represents a shift value. However, there is no sanity check on the shift result and the sbi->record_bits calculation through blksize_bits() assumes the size always > 256, which could lead to NPD while mounting a malformed NTFS image. [ 318.675159] BUG: kernel NULL pointer dereference, address: 0000000000000158 [ 318.675682] #PF: supervisor read access in kernel mode [ 318.675869] #PF: error_code(0x0000) - not-present page [ 318.676246] PGD 0 P4D 0 [ 318.676502] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 318.676934] CPU: 0 PID: 259 Comm: mount Not tainted 5.19.0 #5 [ 318.677289] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 318.678136] RIP: 0010:ni_find_attr+0x2d/0x1c0 [ 318.678656] Code: 89 ca 4d 89 c7 41 56 41 55 41 54 41 89 cc 55 48 89 fd 53 48 89 d3 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 44 24 180 [ 318.679848] RSP: 0018:ffffa6c8c0297bd8 EFLAGS: 00000246 [ 318.680104] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000080 [ 318.680790] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 318.681679] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 318.682577] R10: 0000000000000000 R11: 0000000000000005 R12: 0000000000000080 [ 318.683015] R13: ffff8d5582e68400 R14: 0000000000000100 R15: 0000000000000000 [ 318.683618] FS: 00007fd9e1c81e40(0000) GS:ffff8d55fdc00000(0000) knlGS:0000000000000000 [ 318.684280] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 318.684651] CR2: 0000000000000158 CR3: 0000000002e1a000 CR4: 00000000000006f0 [ 318.685623] Call Trace: [ 318.686607] <TASK> [ 318.686872] ? ntfs_alloc_inode+0x1a/0x60 [ 318.687235] attr_load_runs_vcn+0x2b/0xa0 [ 318.687468] mi_read+0xbb/0x250 [ 318.687576] ntfs_iget5+0x114/0xd90 [ 318.687750] ntfs_fill_super+0x588/0x11b0 [ 318.687953] ? put_ntfs+0x130/0x130 [ 318.688065] ? snprintf+0x49/0x70 [ 318.688164] ? put_ntfs+0x130/0x130 [ 318.688256] get_tree_bdev+0x16a/0x260 [ 318.688407] vfs_get_tree+0x20/0xb0 [ 318.688519] path_mount+0x2dc/0x9b0 [ 318.688877] do_mount+0x74/0x90 [ 318.689142] __x64_sys_mount+0x89/0xd0 [ 318.689636] do_syscall_64+0x3b/0x90 [ 318.689998] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 318.690318] RIP: 0033:0x7fd9e133c48a [ 318.690687] Code: 48 8b 0d 11 fa 2a 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 008 [ 318.691357] RSP: 002b:00007ffd374406c8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 318.691632] RAX: ffffffffffffffda RBX: 0000564d0b051080 RCX: 00007fd9e133c48a [ 318.691920] RDX: 0000564d0b051280 RSI: 0000564d0b051300 RDI: 0000564d0b0596a0 [ 318.692123] RBP: 0000000000000000 R08: 0000564d0b0512a0 R09: 0000000000000020 [ 318.692349] R10: 00000000c0ed0000 R11: 0000000000000202 R12: 0000564d0b0596a0 [ 318.692673] R13: 0000564d0b051280 R14: 0000000000000000 R15: 00000000ffffffff [ 318.693007] </TASK> [ 318.693271] Modules linked in: [ 318.693614] CR2: 0000000000000158 [ 318.694446] ---[ end trace 0000000000000000 ]--- [ 318.694779] RIP: 0010:ni_find_attr+0x2d/0x1c0 [ 318.694952] Code: 89 ca 4d 89 c7 41 56 41 55 41 54 41 89 cc 55 48 89 fd 53 48 89 d3 48 83 ec 20 65 48 8b 04 25 28 00 00 00 48 89 44 24 180 [ 318.696042] RSP: 0018:ffffa6c8c0297bd8 EFLAGS: 00000246 [ 318.696531] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000080 [ 318.698114] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 318.699286] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 318.699795] R10: 0000000000000000 R11: 0000000000000005 R12: 0000000000000080 [ 318.700236] R13: ffff8d5582e68400 R14: 0000000000000100 R15: 0000000000000000 [ 318.700973] FS: 00007fd9e1c81e40(0000) GS:ffff8d55fdc00000(0000) knlGS:0000000000000000 [ ---truncated---

In the Linux kernel, the following vulnerability has been resolved: kprobes: Fix check for probe enabled in kill_kprobe() In kill_kprobe(), the check whether disarm_kprobe_ftrace() needs to be called always fails. This is because before that we set the KPROBE_FLAG_GONE flag for kprobe so that "!kprobe_disabled(p)" is always false. The disarm_kprobe_ftrace() call introduced by commit: 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler") to fix the NULL pointer reference problem. When the probe is enabled, if we do not disarm it, this problem still exists. Fix it by putting the probe enabled check before setting the KPROBE_FLAG_GONE flag.

In the Linux kernel, the following vulnerability has been resolved: btrfs: zoned: initialize device's zone info for seeding When performing seeding on a zoned filesystem it is necessary to initialize each zoned device's btrfs_zoned_device_info structure, otherwise mounting the filesystem will cause a NULL pointer dereference. This was uncovered by fstests' testcase btrfs/163.

In the Linux kernel, the following vulnerability has been resolved: afs: Fix dynamic root getattr The recent patch to make afs_getattr consult the server didn't account for the pseudo-inodes employed by the dynamic root-type afs superblock not having a volume or a server to access, and thus an oops occurs if such a directory is stat'd. Fix this by checking to see if the vnode->volume pointer actually points anywhere before following it in afs_getattr(). This can be tested by stat'ing a directory in /afs. It may be sufficient just to do "ls /afs" and the oops looks something like: BUG: kernel NULL pointer dereference, address: 0000000000000020 ... RIP: 0010:afs_getattr+0x8b/0x14b ... Call Trace: <TASK> vfs_statx+0x79/0xf5 vfs_fstatat+0x49/0x62

In the Linux kernel, the following vulnerability has been resolved: iavf: Fix NULL pointer dereference in iavf_get_link_ksettings Fix possible NULL pointer dereference, due to freeing of adapter->vf_res in iavf_init_get_resources. Previous commit introduced a regression, where receiving IAVF_ERR_ADMIN_QUEUE_NO_WORK from iavf_get_vf_config would free adapter->vf_res. However, netdev is still registered, so ethtool_ops can be called. Calling iavf_get_link_ksettings with no vf_res, will result with: [ 9385.242676] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 9385.242683] #PF: supervisor read access in kernel mode [ 9385.242686] #PF: error_code(0x0000) - not-present page [ 9385.242690] PGD 0 P4D 0 [ 9385.242696] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI [ 9385.242701] CPU: 6 PID: 3217 Comm: pmdalinux Kdump: loaded Tainted: G S E 5.18.0-04958-ga54ce3703613-dirty #1 [ 9385.242708] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.11.0 11/02/2019 [ 9385.242710] RIP: 0010:iavf_get_link_ksettings+0x29/0xd0 [iavf] [ 9385.242745] Code: 00 0f 1f 44 00 00 b8 01 ef ff ff 48 c7 46 30 00 00 00 00 48 c7 46 38 00 00 00 00 c6 46 0b 00 66 89 46 08 48 8b 87 68 0e 00 00 <f6> 40 08 80 75 50 8b 87 5c 0e 00 00 83 f8 08 74 7a 76 1d 83 f8 20 [ 9385.242749] RSP: 0018:ffffc0560ec7fbd0 EFLAGS: 00010246 [ 9385.242755] RAX: 0000000000000000 RBX: ffffc0560ec7fc08 RCX: 0000000000000000 [ 9385.242759] RDX: ffffffffc0ad4550 RSI: ffffc0560ec7fc08 RDI: ffffa0fc66674000 [ 9385.242762] RBP: 00007ffd1fb2bf50 R08: b6a2d54b892363ee R09: ffffa101dc14fb00 [ 9385.242765] R10: 0000000000000000 R11: 0000000000000004 R12: ffffa0fc66674000 [ 9385.242768] R13: 0000000000000000 R14: ffffa0fc66674000 R15: 00000000ffffffa1 [ 9385.242771] FS: 00007f93711a2980(0000) GS:ffffa0fad72c0000(0000) knlGS:0000000000000000 [ 9385.242775] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9385.242778] CR2: 0000000000000008 CR3: 0000000a8e61c003 CR4: 00000000003706e0 [ 9385.242781] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 9385.242784] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 9385.242787] Call Trace: [ 9385.242791] <TASK> [ 9385.242793] ethtool_get_settings+0x71/0x1a0 [ 9385.242814] __dev_ethtool+0x426/0x2f40 [ 9385.242823] ? slab_post_alloc_hook+0x4f/0x280 [ 9385.242836] ? kmem_cache_alloc_trace+0x15d/0x2f0 [ 9385.242841] ? dev_ethtool+0x59/0x170 [ 9385.242848] dev_ethtool+0xa7/0x170 [ 9385.242856] dev_ioctl+0xc3/0x520 [ 9385.242866] sock_do_ioctl+0xa0/0xe0 [ 9385.242877] sock_ioctl+0x22f/0x320 [ 9385.242885] __x64_sys_ioctl+0x84/0xc0 [ 9385.242896] do_syscall_64+0x3a/0x80 [ 9385.242904] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 9385.242918] RIP: 0033:0x7f93702396db [ 9385.242923] Code: 73 01 c3 48 8b 0d ad 57 38 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 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 7d 57 38 00 f7 d8 64 89 01 48 [ 9385.242927] RSP: 002b:00007ffd1fb2bf18 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 9385.242932] RAX: ffffffffffffffda RBX: 000055671b1d2fe0 RCX: 00007f93702396db [ 9385.242935] RDX: 00007ffd1fb2bf20 RSI: 0000000000008946 RDI: 0000000000000007 [ 9385.242937] RBP: 00007ffd1fb2bf20 R08: 0000000000000003 R09: 0030763066307330 [ 9385.242940] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd1fb2bf80 [ 9385.242942] R13: 0000000000000007 R14: 0000556719f6de90 R15: 00007ffd1fb2c1b0 [ 9385.242948] </TASK> [ 9385.242949] Modules linked in: iavf(E) xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nft_compat nf_nat_tftp nft_objref nf_conntrack_tftp bridge stp llc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables rfkill nfnetlink vfat fat irdma ib_uverbs ib_core intel_rapl_msr intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretem ---truncated---

In the Linux kernel, the following vulnerability has been resolved: drm/ttm: Fix dummy res NULL ptr deref bug Check the bo->resource value before accessing the resource mem_type. v2: Fix commit description unwrapped warning <log snip> [ 40.191227][ T184] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN PTI [ 40.192995][ T184] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] [ 40.194411][ T184] CPU: 1 PID: 184 Comm: systemd-udevd Not tainted 5.19.0-rc4-00721-gb297c22b7070 #1 [ 40.196063][ T184] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014 [ 40.199605][ T184] RIP: 0010:ttm_bo_validate+0x1b3/0x240 [ttm] [ 40.200754][ T184] Code: e8 72 c5 ff ff 83 f8 b8 74 d4 85 c0 75 54 49 8b 9e 58 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 10 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 44 8b 53 10 31 c0 85 d2 0f 85 58 [ 40.203685][ T184] RSP: 0018:ffffc900006df0c8 EFLAGS: 00010202 [ 40.204630][ T184] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff1102f4bb71b [ 40.205864][ T184] RDX: 0000000000000002 RSI: ffffc900006df208 RDI: 0000000000000010 [ 40.207102][ T184] RBP: 1ffff920000dbe1a R08: ffffc900006df208 R09: 0000000000000000 [ 40.208394][ T184] R10: ffff88817a5f0000 R11: 0000000000000001 R12: ffffc900006df110 [ 40.209692][ T184] R13: ffffc900006df0f0 R14: ffff88817a5db800 R15: ffffc900006df208 [ 40.210862][ T184] FS: 00007f6b1d16e8c0(0000) GS:ffff88839d700000(0000) knlGS:0000000000000000 [ 40.212250][ T184] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 40.213275][ T184] CR2: 000055a1001d4ff0 CR3: 00000001700f4000 CR4: 00000000000006e0 [ 40.214469][ T184] Call Trace: [ 40.214974][ T184] <TASK> [ 40.215438][ T184] ? ttm_bo_bounce_temp_buffer+0x140/0x140 [ttm] [ 40.216572][ T184] ? mutex_spin_on_owner+0x240/0x240 [ 40.217456][ T184] ? drm_vma_offset_add+0xaa/0x100 [drm] [ 40.218457][ T184] ttm_bo_init_reserved+0x3d6/0x540 [ttm] [ 40.219410][ T184] ? shmem_get_inode+0x744/0x980 [ 40.220231][ T184] ttm_bo_init_validate+0xb1/0x200 [ttm] [ 40.221172][ T184] ? bo_driver_evict_flags+0x340/0x340 [drm_vram_helper] [ 40.222530][ T184] ? ttm_bo_init_reserved+0x540/0x540 [ttm] [ 40.223643][ T184] ? __do_sys_finit_module+0x11a/0x1c0 [ 40.224654][ T184] ? __shmem_file_setup+0x102/0x280 [ 40.234764][ T184] drm_gem_vram_create+0x305/0x480 [drm_vram_helper] [ 40.235766][ T184] ? bo_driver_evict_flags+0x340/0x340 [drm_vram_helper] [ 40.236846][ T184] ? __kasan_slab_free+0x108/0x180 [ 40.237650][ T184] drm_gem_vram_fill_create_dumb+0x134/0x340 [drm_vram_helper] [ 40.238864][ T184] ? local_pci_probe+0xdf/0x180 [ 40.239674][ T184] ? drmm_vram_helper_init+0x400/0x400 [drm_vram_helper] [ 40.240826][ T184] drm_client_framebuffer_create+0x19c/0x400 [drm] [ 40.241955][ T184] ? drm_client_buffer_delete+0x200/0x200 [drm] [ 40.243001][ T184] ? drm_client_pick_crtcs+0x554/0xb80 [drm] [ 40.244030][ T184] drm_fb_helper_generic_probe+0x23f/0x940 [drm_kms_helper] [ 40.245226][ T184] ? __cond_resched+0x1c/0xc0 [ 40.245987][ T184] ? drm_fb_helper_memory_range_to_clip+0x180/0x180 [drm_kms_helper] [ 40.247316][ T184] ? mutex_unlock+0x80/0x100 [ 40.248005][ T184] ? __mutex_unlock_slowpath+0x2c0/0x2c0 [ 40.249083][ T184] drm_fb_helper_single_fb_probe+0x907/0xf00 [drm_kms_helper] [ 40.250314][ T184] ? drm_fb_helper_check_var+0x1180/0x1180 [drm_kms_helper] [ 40.251540][ T184] ? __cond_resched+0x1c/0xc0 [ 40.252321][ T184] ? mutex_lock+0x9f/0x100 [ 40.253062][ T184] __drm_fb_helper_initial_config_and_unlock+0xb9/0x2c0 [drm_kms_helper] [ 40.254394][ T184] drm_fbdev_client_hotplug+0x56f/0x840 [drm_kms_helper] [ 40.255477][ T184] drm_fbdev_generic_setup+0x165/0x3c0 [drm_kms_helper] [ 40.256607][ T184] bochs_pci_probe+0x6b7/0x900 [bochs] [ ---truncated---

In the Linux kernel, the following vulnerability has been resolved: dmaengine: sf-pdma: Add multithread support for a DMA channel When we get a DMA channel and try to use it in multiple threads it will cause oops and hanging the system. % echo 64 > /sys/module/dmatest/parameters/threads_per_chan % echo 10000 > /sys/module/dmatest/parameters/iterations % echo 1 > /sys/module/dmatest/parameters/run [ 89.480664] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0 [ 89.488725] Oops [#1] [ 89.494708] CPU: 2 PID: 1008 Comm: dma0chan0-copy0 Not tainted 5.17.0-rc5 [ 89.509385] epc : vchan_find_desc+0x32/0x46 [ 89.513553] ra : sf_pdma_tx_status+0xca/0xd6 This happens because of data race. Each thread rewrite channels's descriptor as soon as device_prep_dma_memcpy() is called. It leads to the situation when the driver thinks that it uses right descriptor that actually is freed or substituted for other one. With current fixes a descriptor changes its value only when it has been used. A new descriptor is acquired from vc->desc_issued queue that is already filled with descriptors that are ready to be sent. Threads have no direct access to DMA channel descriptor. Now it is just possible to queue a descriptor for further processing.

In the Linux kernel, the following vulnerability has been resolved: xfrm: policy: fix metadata dst->dev xmit null pointer dereference When we try to transmit an skb with metadata_dst attached (i.e. dst->dev == NULL) through xfrm interface we can hit a null pointer dereference[1] in xfrmi_xmit2() -> xfrm_lookup_with_ifid() due to the check for a loopback skb device when there's no policy which dereferences dst->dev unconditionally. Not having dst->dev can be interepreted as it not being a loopback device, so just add a check for a null dst_orig->dev. With this fix xfrm interface's Tx error counters go up as usual. [1] net-next calltrace captured via netconsole: BUG: kernel NULL pointer dereference, address: 00000000000000c0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 1 PID: 7231 Comm: ping Kdump: loaded Not tainted 5.19.0+ #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-1.fc36 04/01/2014 RIP: 0010:xfrm_lookup_with_ifid+0x5eb/0xa60 Code: 8d 74 24 38 e8 26 a4 37 00 48 89 c1 e9 12 fc ff ff 49 63 ed 41 83 fd be 0f 85 be 01 00 00 41 be ff ff ff ff 45 31 ed 48 8b 03 <f6> 80 c0 00 00 00 08 75 0f 41 80 bc 24 19 0d 00 00 01 0f 84 1e 02 RSP: 0018:ffffb0db82c679f0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffd0db7fcad430 RCX: ffffb0db82c67a10 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb0db82c67a80 RBP: ffffb0db82c67a80 R08: ffffb0db82c67a14 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8fa449667dc8 R12: ffffffff966db880 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 FS: 00007ff35c83f000(0000) GS:ffff8fa478480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000c0 CR3: 000000001ebb7000 CR4: 0000000000350ee0 Call Trace: <TASK> xfrmi_xmit+0xde/0x460 ? tcf_bpf_act+0x13d/0x2a0 dev_hard_start_xmit+0x72/0x1e0 __dev_queue_xmit+0x251/0xd30 ip_finish_output2+0x140/0x550 ip_push_pending_frames+0x56/0x80 raw_sendmsg+0x663/0x10a0 ? try_charge_memcg+0x3fd/0x7a0 ? __mod_memcg_lruvec_state+0x93/0x110 ? sock_sendmsg+0x30/0x40 sock_sendmsg+0x30/0x40 __sys_sendto+0xeb/0x130 ? handle_mm_fault+0xae/0x280 ? do_user_addr_fault+0x1e7/0x680 ? kvm_read_and_reset_apf_flags+0x3b/0x50 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7ff35cac1366 Code: eb 0b 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 72 c3 90 55 48 83 ec 30 44 89 4c 24 2c 4c 89 RSP: 002b:00007fff738e4028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fff738e57b0 RCX: 00007ff35cac1366 RDX: 0000000000000040 RSI: 0000557164e4b450 RDI: 0000000000000003 RBP: 0000557164e4b450 R08: 00007fff738e7a2c R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 00007fff738e5770 R14: 00007fff738e4030 R15: 0000001d00000001 </TASK> Modules linked in: netconsole veth br_netfilter bridge bonding virtio_net [last unloaded: netconsole] CR2: 00000000000000c0

In the Linux kernel, the following vulnerability has been resolved: drm/i915: fix null pointer dereference Asus chromebook CX550 crashes during boot on v5.17-rc1 kernel. The root cause is null pointer defeference of bi_next in tgl_get_bw_info() in drivers/gpu/drm/i915/display/intel_bw.c. BUG: kernel NULL pointer dereference, address: 000000000000002e PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 1 Comm: swapper/0 Tainted: G U 5.17.0-rc1 Hardware name: Google Delbin/Delbin, BIOS Google_Delbin.13672.156.3 05/14/2021 RIP: 0010:tgl_get_bw_info+0x2de/0x510 ... [ 2.554467] Call Trace: [ 2.554467] <TASK> [ 2.554467] intel_bw_init_hw+0x14a/0x434 [ 2.554467] ? _printk+0x59/0x73 [ 2.554467] ? _dev_err+0x77/0x91 [ 2.554467] i915_driver_hw_probe+0x329/0x33e [ 2.554467] i915_driver_probe+0x4c8/0x638 [ 2.554467] i915_pci_probe+0xf8/0x14e [ 2.554467] ? _raw_spin_unlock_irqrestore+0x12/0x2c [ 2.554467] pci_device_probe+0xaa/0x142 [ 2.554467] really_probe+0x13f/0x2f4 [ 2.554467] __driver_probe_device+0x9e/0xd3 [ 2.554467] driver_probe_device+0x24/0x7c [ 2.554467] __driver_attach+0xba/0xcf [ 2.554467] ? driver_attach+0x1f/0x1f [ 2.554467] bus_for_each_dev+0x8c/0xc0 [ 2.554467] bus_add_driver+0x11b/0x1f7 [ 2.554467] driver_register+0x60/0xea [ 2.554467] ? mipi_dsi_bus_init+0x16/0x16 [ 2.554467] i915_init+0x2c/0xb9 [ 2.554467] ? mipi_dsi_bus_init+0x16/0x16 [ 2.554467] do_one_initcall+0x12e/0x2b3 [ 2.554467] do_initcall_level+0xd6/0xf3 [ 2.554467] do_initcalls+0x4e/0x79 [ 2.554467] kernel_init_freeable+0xed/0x14d [ 2.554467] ? rest_init+0xc1/0xc1 [ 2.554467] kernel_init+0x1a/0x120 [ 2.554467] ret_from_fork+0x1f/0x30 [ 2.554467] </TASK> ... Kernel panic - not syncing: Fatal exception (cherry picked from commit c247cd03898c4c43c3bce6d4014730403bc13032)

In the Linux kernel, the following vulnerability has been resolved: igc: Reinstate IGC_REMOVED logic and implement it properly The initially merged version of the igc driver code (via commit 146740f9abc4, "igc: Add support for PF") contained the following IGC_REMOVED checks in the igc_rd32/wr32() MMIO accessors: u32 igc_rd32(struct igc_hw *hw, u32 reg) { u8 __iomem *hw_addr = READ_ONCE(hw->hw_addr); u32 value = 0; if (IGC_REMOVED(hw_addr)) return ~value; value = readl(&hw_addr[reg]); /* reads should not return all F's */ if (!(~value) && (!reg || !(~readl(hw_addr)))) hw->hw_addr = NULL; return value; } And: #define wr32(reg, val) \ do { \ u8 __iomem *hw_addr = READ_ONCE((hw)->hw_addr); \ if (!IGC_REMOVED(hw_addr)) \ writel((val), &hw_addr[(reg)]); \ } while (0) E.g. igb has similar checks in its MMIO accessors, and has a similar macro E1000_REMOVED, which is implemented as follows: #define E1000_REMOVED(h) unlikely(!(h)) These checks serve to detect and take note of an 0xffffffff MMIO read return from the device, which can be caused by a PCIe link flap or some other kind of PCI bus error, and to avoid performing MMIO reads and writes from that point onwards. However, the IGC_REMOVED macro was not originally implemented: #ifndef IGC_REMOVED #define IGC_REMOVED(a) (0) #endif /* IGC_REMOVED */ This led to the IGC_REMOVED logic to be removed entirely in a subsequent commit (commit 3c215fb18e70, "igc: remove IGC_REMOVED function"), with the rationale that such checks matter only for virtualization and that igc does not support virtualization -- but a PCIe device can become detached even without virtualization being in use, and without proper checks, a PCIe bus error affecting an igc adapter will lead to various NULL pointer dereferences, as the first access after the error will set hw->hw_addr to NULL, and subsequent accesses will blindly dereference this now-NULL pointer. This patch reinstates the IGC_REMOVED checks in igc_rd32/wr32(), and implements IGC_REMOVED the way it is done for igb, by checking for the unlikely() case of hw_addr being NULL. This change prevents the oopses seen when a PCIe link flap occurs on an igc adapter.

In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Fix BUG: KASAN: null-ptr-deref in rxe_qp_do_cleanup The function rxe_create_qp calls rxe_qp_from_init. If some error occurs, the error handler of function rxe_qp_from_init will set both scq and rcq to NULL. Then rxe_create_qp calls rxe_put to handle qp. In the end, rxe_qp_do_cleanup is called by rxe_put. rxe_qp_do_cleanup directly accesses scq and rcq before checking them. This will cause null-ptr-deref error. The call graph is as below: rxe_create_qp { ... rxe_qp_from_init { ... err1: ... qp->rcq = NULL; <---rcq is set to NULL qp->scq = NULL; <---scq is set to NULL ... } qp_init: rxe_put{ ... rxe_qp_do_cleanup { ... atomic_dec(&qp->scq->num_wq); <--- scq is accessed ... atomic_dec(&qp->rcq->num_wq); <--- rcq is accessed } }

In the Linux kernel, the following vulnerability has been resolved: Revert "usb: typec: ucsi: add a common function ucsi_unregister_connectors()" The recent commit 87d0e2f41b8c ("usb: typec: ucsi: add a common function ucsi_unregister_connectors()") introduced a regression that caused NULL dereference at reading the power supply sysfs. It's a stale sysfs entry that should have been removed but remains with NULL ops. The commit changed the error handling to skip the entries after a NULL con->wq, and this leaves the power device unreleased. For addressing the regression, the straight revert is applied here. Further code improvements can be done from the scratch again.

In the Linux kernel, the following vulnerability has been resolved: drm/bridge: megachips: Fix a null pointer dereference bug When removing the module we will get the following warning: [ 31.911505] i2c-core: driver [stdp2690-ge-b850v3-fw] unregistered [ 31.912484] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI [ 31.913338] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] [ 31.915280] RIP: 0010:drm_bridge_remove+0x97/0x130 [ 31.921825] Call Trace: [ 31.922533] stdp4028_ge_b850v3_fw_remove+0x34/0x60 [megachips_stdpxxxx_ge_b850v3_fw] [ 31.923139] i2c_device_remove+0x181/0x1f0 The two bridges (stdp2690, stdp4028) do not probe at the same time, so the driver does not call ge_b850v3_resgiter() when probing, causing the driver to try to remove the object that has not been initialized. Fix this by checking whether both the bridges are probed.

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

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: fix possible null-ptr-deref in arm_smmu_device_probe() It will cause null-ptr-deref when using 'res', if platform_get_resource() returns NULL, so move using 'res' after devm_ioremap_resource() that will check it to avoid null-ptr-deref. And use devm_platform_get_and_ioremap_resource() to simplify code.

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

In the Linux kernel, the following vulnerability has been resolved: hwmon: (nct6775) Fix crash in clear_caseopen Paweł Marciniak reports the following crash, observed when clearing the chassis intrusion alarm. BUG: kernel NULL pointer dereference, address: 0000000000000028 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 3 PID: 4815 Comm: bash Tainted: G S 5.16.2-200.fc35.x86_64 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z97 Extreme4, BIOS P2.60A 05/03/2018 RIP: 0010:clear_caseopen+0x5a/0x120 [nct6775] Code: 68 70 e8 e9 32 b1 e3 85 c0 0f 85 d2 00 00 00 48 83 7c 24 ... RSP: 0018:ffffabcb02803dd8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 RDX: ffff8e8808192880 RSI: 0000000000000000 RDI: ffff8e87c7509a68 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000000000a R10: 000000000000000a R11: f000000000000000 R12: 000000000000001f R13: ffff8e87c7509828 R14: ffff8e87c7509a68 R15: ffff8e88494527a0 FS: 00007f4db9151740(0000) GS:ffff8e8ebfec0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000028 CR3: 0000000166b66001 CR4: 00000000001706e0 Call Trace: <TASK> kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x10b/0x180 vfs_write+0x209/0x2a0 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae The problem is that the device passed to clear_caseopen() is the hwmon device, not the platform device, and the platform data is not set in the hwmon device. Store the pointer to sio_data in struct nct6775_data and get if from there if needed.

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix NULL pointer dereference in nilfs_palloc_commit_free_entry() Syzbot reported a null-ptr-deref bug: NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 1 PID: 3603 Comm: segctord Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 RIP: 0010:nilfs_palloc_commit_free_entry+0xe5/0x6b0 fs/nilfs2/alloc.c:608 Code: 00 00 00 00 fc ff df 80 3c 02 00 0f 85 cd 05 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 73 08 49 8d 7e 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 26 05 00 00 49 8b 46 10 be a6 00 00 00 48 c7 c7 RSP: 0018:ffffc90003dff830 EFLAGS: 00010212 RAX: dffffc0000000000 RBX: ffff88802594e218 RCX: 000000000000000d RDX: 0000000000000002 RSI: 0000000000002000 RDI: 0000000000000010 RBP: ffff888071880222 R08: 0000000000000005 R09: 000000000000003f R10: 000000000000000d R11: 0000000000000000 R12: ffff888071880158 R13: ffff88802594e220 R14: 0000000000000000 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb1c08316a8 CR3: 0000000018560000 CR4: 0000000000350ee0 Call Trace: <TASK> nilfs_dat_commit_free fs/nilfs2/dat.c:114 [inline] nilfs_dat_commit_end+0x464/0x5f0 fs/nilfs2/dat.c:193 nilfs_dat_commit_update+0x26/0x40 fs/nilfs2/dat.c:236 nilfs_btree_commit_update_v+0x87/0x4a0 fs/nilfs2/btree.c:1940 nilfs_btree_commit_propagate_v fs/nilfs2/btree.c:2016 [inline] nilfs_btree_propagate_v fs/nilfs2/btree.c:2046 [inline] nilfs_btree_propagate+0xa00/0xd60 fs/nilfs2/btree.c:2088 nilfs_bmap_propagate+0x73/0x170 fs/nilfs2/bmap.c:337 nilfs_collect_file_data+0x45/0xd0 fs/nilfs2/segment.c:568 nilfs_segctor_apply_buffers+0x14a/0x470 fs/nilfs2/segment.c:1018 nilfs_segctor_scan_file+0x3f4/0x6f0 fs/nilfs2/segment.c:1067 nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1197 [inline] nilfs_segctor_collect fs/nilfs2/segment.c:1503 [inline] nilfs_segctor_do_construct+0x12fc/0x6af0 fs/nilfs2/segment.c:2045 nilfs_segctor_construct+0x8e3/0xb30 fs/nilfs2/segment.c:2379 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2487 [inline] nilfs_segctor_thread+0x3c3/0xf30 fs/nilfs2/segment.c:2570 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> ... If DAT metadata file is corrupted on disk, there is a case where req->pr_desc_bh is NULL and blocknr is 0 at nilfs_dat_commit_end() during a b-tree operation that cascadingly updates ancestor nodes of the b-tree, because nilfs_dat_commit_alloc() for a lower level block can initialize the blocknr on the same DAT entry between nilfs_dat_prepare_end() and nilfs_dat_commit_end(). If this happens, nilfs_dat_commit_end() calls nilfs_dat_commit_free() without valid buffer heads in req->pr_desc_bh and req->pr_bitmap_bh, and causes the NULL pointer dereference above in nilfs_palloc_commit_free_entry() function, which leads to a crash. Fix this by adding a NULL check on req->pr_desc_bh and req->pr_bitmap_bh before nilfs_palloc_commit_free_entry() in nilfs_dat_commit_free(). This also calls nilfs_error() in that case to notify that there is a fatal flaw in the filesystem metadata and prevent further operations.

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

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix a NULL pointer dereference in amdgpu_dm_connector_add_common_modes() In amdgpu_dm_connector_add_common_modes(), amdgpu_dm_create_common_mode() is assigned to mode and is passed to drm_mode_probed_add() directly after that. drm_mode_probed_add() passes &mode->head to list_add_tail(), and there is a dereference of it in list_add_tail() without recoveries, which could lead to NULL pointer dereference on failure of amdgpu_dm_create_common_mode(). Fix this by adding a NULL check of mode. This bug was found by a static analyzer. Builds with 'make allyesconfig' show no new warnings, and our static analyzer no longer warns about this code.

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu-v3: 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: vduse: Fix NULL pointer dereference on sysfs access The control device has no drvdata. So we will get a NULL pointer dereference when accessing control device's msg_timeout attribute via sysfs: [ 132.841881][ T3644] BUG: kernel NULL pointer dereference, address: 00000000000000f8 [ 132.850619][ T3644] RIP: 0010:msg_timeout_show (drivers/vdpa/vdpa_user/vduse_dev.c:1271) [ 132.869447][ T3644] dev_attr_show (drivers/base/core.c:2094) [ 132.870215][ T3644] sysfs_kf_seq_show (fs/sysfs/file.c:59) [ 132.871164][ T3644] ? device_remove_bin_file (drivers/base/core.c:2088) [ 132.872082][ T3644] kernfs_seq_show (fs/kernfs/file.c:164) [ 132.872838][ T3644] seq_read_iter (fs/seq_file.c:230) [ 132.873578][ T3644] ? __vmalloc_area_node (mm/vmalloc.c:3041) [ 132.874532][ T3644] kernfs_fop_read_iter (fs/kernfs/file.c:238) [ 132.875513][ T3644] __kernel_read (fs/read_write.c:440 (discriminator 1)) [ 132.876319][ T3644] kernel_read (fs/read_write.c:459) [ 132.877129][ T3644] kernel_read_file (fs/kernel_read_file.c:94) [ 132.877978][ T3644] kernel_read_file_from_fd (include/linux/file.h:45 fs/kernel_read_file.c:186) [ 132.879019][ T3644] __do_sys_finit_module (kernel/module.c:4207) [ 132.879930][ T3644] __ia32_sys_finit_module (kernel/module.c:4189) [ 132.880930][ T3644] do_int80_syscall_32 (arch/x86/entry/common.c:112 arch/x86/entry/common.c:132) [ 132.881847][ T3644] entry_INT80_compat (arch/x86/entry/entry_64_compat.S:419) To fix it, don't create the unneeded attribute for control device anymore.

In the Linux kernel, the following vulnerability has been resolved: media: lgdt3306a: Add a check against null-pointer-def The driver should check whether the client provides the platform_data. The following log reveals it: [ 29.610324] BUG: KASAN: null-ptr-deref in kmemdup+0x30/0x40 [ 29.610730] Read of size 40 at addr 0000000000000000 by task bash/414 [ 29.612820] Call Trace: [ 29.613030] <TASK> [ 29.613201] dump_stack_lvl+0x56/0x6f [ 29.613496] ? kmemdup+0x30/0x40 [ 29.613754] print_report.cold+0x494/0x6b7 [ 29.614082] ? kmemdup+0x30/0x40 [ 29.614340] kasan_report+0x8a/0x190 [ 29.614628] ? kmemdup+0x30/0x40 [ 29.614888] kasan_check_range+0x14d/0x1d0 [ 29.615213] memcpy+0x20/0x60 [ 29.615454] kmemdup+0x30/0x40 [ 29.615700] lgdt3306a_probe+0x52/0x310 [ 29.616339] i2c_device_probe+0x951/0xa90

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: 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: tty: fix possible null-ptr-defer in spk_ttyio_release Run the following tests on the qemu platform: syzkaller:~# modprobe speakup_audptr input: Speakup as /devices/virtual/input/input4 initialized device: /dev/synth, node (MAJOR 10, MINOR 125) speakup 3.1.6: initialized synth name on entry is: (null) synth probe spk_ttyio_initialise_ldisc failed because tty_kopen_exclusive returned failed (errno -16), then remove the module, we will get a null-ptr-defer problem, as follow: syzkaller:~# modprobe -r speakup_audptr releasing synth audptr BUG: kernel NULL pointer dereference, address: 0000000000000080 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP PTI CPU: 2 PID: 204 Comm: modprobe Not tainted 6.1.0-rc6-dirty #1 RIP: 0010:mutex_lock+0x14/0x30 Call Trace: <TASK> spk_ttyio_release+0x19/0x70 [speakup] synth_release.part.6+0xac/0xc0 [speakup] synth_remove+0x56/0x60 [speakup] __x64_sys_delete_module+0x156/0x250 ? fpregs_assert_state_consistent+0x1d/0x50 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK> Modules linked in: speakup_audptr(-) speakup Dumping ftrace buffer: in_synth->dev was not initialized during modprobe, so we add check for in_synth->dev to fix this bug.

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu-v3: Don't unregister on shutdown Similar to SMMUv2, this driver calls iommu_device_unregister() from the shutdown path, which removes the IOMMU groups with no coordination whatsoever with their users - shutdown methods are optional in device drivers. This can lead to NULL pointer dereferences in those drivers' DMA API calls, or worse. Instead of calling the full arm_smmu_device_remove() from arm_smmu_device_shutdown(), let's pick only the relevant function call - arm_smmu_device_disable() - more or less the reverse of arm_smmu_device_reset() - and call just that from the shutdown path.