NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: drm/ttm: Fix a NULL pointer dereference The LRU mechanism may look up a resource in the process of being removed from an object. The locking rules here are a bit unclear but it looks currently like res->bo assignment is protected by the LRU lock, whereas bo->resource is protected by the object lock, while *clearing* of bo->resource is also protected by the LRU lock. This means that if we check that bo->resource points to the LRU resource under the LRU lock we should be safe. So perform that check before deciding to swap out a bo. That avoids dereferencing a NULL bo->resource in ttm_bo_swapout().Show less

In the Linux kernel, the following vulnerability has been resolved: tracing: Do not let histogram values have some modifiers Histogram values can not be strings, stacktraces, graphs, symbols, syscalls, or grouped in buckets or log. Give an error if a value is set to do so. Note, the histogram code was not prepared to handle these modifiers for histograms and caused a bug. Mark Rutland reported: # echo 'p:copy_to_user __arch_copy_to_user n=$arg2' >> /sys/kernel/tracing/kprobe_events # echo 'hist:keys=n:vals=hitcount.buckets=8:sort=hitcount' > /sys/kernel/tracing/events/kprobes/copy_to_user/trigger # cat /sys/kernel/tracing/events/kprobes/copy_to_user/hist [ 143.694628] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 143.695190] Mem abort info: [ 143.695362] ESR = 0x0000000096000004 [ 143.695604] EC = 0x25: DABT (current EL), IL = 32 bits [ 143.695889] SET = 0, FnV = 0 [ 143.696077] EA = 0, S1PTW = 0 [ 143.696302] FSC = 0x04: level 0 translation fault [ 143.702381] Data abort info: [ 143.702614] ISV = 0, ISS = 0x00000004 [ 143.702832] CM = 0, WnR = 0 [ 143.703087] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000448f9000 [ 143.703407] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 [ 143.704137] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 143.704714] Modules linked in: [ 143.705273] CPU: 0 PID: 133 Comm: cat Not tainted 6.2.0-00003-g6fc512c10a7c #3 [ 143.706138] Hardware name: linux,dummy-virt (DT) [ 143.706723] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 143.707120] pc : hist_field_name.part.0+0x14/0x140 [ 143.707504] lr : hist_field_name.part.0+0x104/0x140 [ 143.707774] sp : ffff800008333a30 [ 143.707952] x29: ffff800008333a30 x28: 0000000000000001 x27: 0000000000400cc0 [ 143.708429] x26: ffffd7a653b20260 x25: 0000000000000000 x24: ffff10d303ee5800 [ 143.708776] x23: ffffd7a6539b27b0 x22: ffff10d303fb8c00 x21: 0000000000000001 [ 143.709127] x20: ffff10d303ec2000 x19: 0000000000000000 x18: 0000000000000000 [ 143.709478] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 143.709824] x14: 0000000000000000 x13: 203a6f666e692072 x12: 6567676972742023 [ 143.710179] x11: 0a230a6d6172676f x10: 000000000000002c x9 : ffffd7a6521e018c [ 143.710584] x8 : 000000000000002c x7 : 7f7f7f7f7f7f7f7f x6 : 000000000000002c [ 143.710915] x5 : ffff10d303b0103e x4 : ffffd7a653b20261 x3 : 000000000000003d [ 143.711239] x2 : 0000000000020001 x1 : 0000000000000001 x0 : 0000000000000000 [ 143.711746] Call trace: [ 143.712115] hist_field_name.part.0+0x14/0x140 [ 143.712642] hist_field_name.part.0+0x104/0x140 [ 143.712925] hist_field_print+0x28/0x140 [ 143.713125] event_hist_trigger_print+0x174/0x4d0 [ 143.713348] hist_show+0xf8/0x980 [ 143.713521] seq_read_iter+0x1bc/0x4b0 [ 143.713711] seq_read+0x8c/0xc4 [ 143.713876] vfs_read+0xc8/0x2a4 [ 143.714043] ksys_read+0x70/0xfc [ 143.714218] __arm64_sys_read+0x24/0x30 [ 143.714400] invoke_syscall+0x50/0x120 [ 143.714587] el0_svc_common.constprop.0+0x4c/0x100 [ 143.714807] do_el0_svc+0x44/0xd0 [ 143.714970] el0_svc+0x2c/0x84 [ 143.715134] el0t_64_sync_handler+0xbc/0x140 [ 143.715334] el0t_64_sync+0x190/0x194 [ 143.715742] Code: a9bd7bfd 910003fd a90153f3 aa0003f3 (f9400000) [ 143.716510] ---[ end trace 0000000000000000 ]--- Segmentation faultShow less

In the Linux kernel, the following vulnerability has been resolved: ext4: update s_journal_inum if it changes after journal replay When mounting a crafted ext4 image, s_journal_inum may change after journal replay, which is obviously unreasonable because we have successfully loaded and replayed the journal through the old s_journal_inum. And the new s_journal_inum bypasses some of the checks in ext4_get_journal(), which may trigger a null pointer dereference problem. So if s_journal_inum changes after the journal replay, we ignore the change, and rewrite the current journal_inum to the superblock.Show less

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix steering rules cleanup vport's mc, uc and multicast rules are not deleted in teardown path when EEH happens. Since the vport's promisc settings(uc, mc and all) in firmware are reset after EEH, mlx5 driver will try to delete the above rules in the initialization path. This cause kernel crash because these software rules are no longer valid. Fix by nullifying these rules right after delete to avoid accessing any dangling pointers. Call Trace: __list_del_entry_valid+0xcc/0x100 (unreliable) tree_put_node+0xf4/0x1b0 [mlx5_core] tree_remove_node+0x30/0x70 [mlx5_core] mlx5_del_flow_rules+0x14c/0x1f0 [mlx5_core] esw_apply_vport_rx_mode+0x10c/0x200 [mlx5_core] esw_update_vport_rx_mode+0xb4/0x180 [mlx5_core] esw_vport_change_handle_locked+0x1ec/0x230 [mlx5_core] esw_enable_vport+0x130/0x260 [mlx5_core] mlx5_eswitch_enable_sriov+0x2a0/0x2f0 [mlx5_core] mlx5_device_enable_sriov+0x74/0x440 [mlx5_core] mlx5_load_one+0x114c/0x1550 [mlx5_core] mlx5_pci_resume+0x68/0xf0 [mlx5_core] eeh_report_resume+0x1a4/0x230 eeh_pe_dev_traverse+0x98/0x170 eeh_handle_normal_event+0x3e4/0x640 eeh_handle_event+0x4c/0x370 eeh_event_handler+0x14c/0x210 kthread+0x168/0x1b0 ret_from_kernel_thread+0x5c/0x84Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: do not run mt76_unregister_device() on unregistered hw Trying to probe a mt7921e pci card without firmware results in a successful probe where ieee80211_register_hw hasn't been called. When removing the driver, ieee802111_unregister_hw is called unconditionally leading to a kernel NULL pointer dereference. Fix the issue running mt76_unregister_device routine just for registered hw.Show less

In the Linux kernel, the following vulnerability has been resolved: qed/qed_sriov: guard against NULL derefs from qed_iov_get_vf_info We have to make sure that the info returned by the helper is valid before using it. Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool.Show less

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: E-Switch, Fix an Oops in error handling code The error handling dereferences "vport". There is nothing we can do if it is an error pointer except returning the error code.Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Synchronize the IOCB count to be in order A system hang was observed with the following call trace: BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 15 PID: 86747 Comm: nvme Kdump: loaded Not tainted 6.2.0+ #1 Hardware name: Dell Inc. PowerEdge R6515/04F3CJ, BIOS 2.7.3 03/31/2022 RIP: 0010:__wake_up_common+0x55/0x190 Code: 41 f6 01 04 0f 85 b2 00 00 00 48 8b 43 08 4c 8d 40 e8 48 8d 43 08 48 89 04 24 48 89 c6\ 49 8d 40 18 48 39 c6 0f 84 e9 00 00 00 <49> 8b 40 18 89 6c 24 14 31 ed 4c 8d 60 e8 41 8b 18 f6 c3 04 75 5d RSP: 0018:ffffb05a82afbba0 EFLAGS: 00010082 RAX: 0000000000000000 RBX: ffff8f9b83a00018 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffff8f9b83a00020 RDI: ffff8f9b83a00018 RBP: 0000000000000001 R08: ffffffffffffffe8 R09: ffffb05a82afbbf8 R10: 70735f7472617473 R11: 5f30307832616c71 R12: 0000000000000001 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f815cf4c740(0000) GS:ffff8f9eeed80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000010633a000 CR4: 0000000000350ee0 Call Trace: <TASK> __wake_up_common_lock+0x83/0xd0 qla_nvme_ls_req+0x21b/0x2b0 [qla2xxx] __nvme_fc_send_ls_req+0x1b5/0x350 [nvme_fc] nvme_fc_xmt_disconnect_assoc+0xca/0x110 [nvme_fc] nvme_fc_delete_association+0x1bf/0x220 [nvme_fc] ? nvme_remove_namespaces+0x9f/0x140 [nvme_core] nvme_do_delete_ctrl+0x5b/0xa0 [nvme_core] nvme_sysfs_delete+0x5f/0x70 [nvme_core] kernfs_fop_write_iter+0x12b/0x1c0 vfs_write+0x2a3/0x3b0 ksys_write+0x5f/0xe0 do_syscall_64+0x5c/0x90 ? syscall_exit_work+0x103/0x130 ? syscall_exit_to_user_mode+0x12/0x30 ? do_syscall_64+0x69/0x90 ? exit_to_user_mode_loop+0xd0/0x130 ? exit_to_user_mode_prepare+0xec/0x100 ? syscall_exit_to_user_mode+0x12/0x30 ? do_syscall_64+0x69/0x90 ? syscall_exit_to_user_mode+0x12/0x30 ? do_syscall_64+0x69/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f815cd3eb97 The IOCB counts are out of order and that would block any commands from going out and subsequently hang the system. Synchronize the IOCB count to be in correct order.Show less

In the Linux kernel, the following vulnerability has been resolved: fscrypt: destroy keyring after security_sb_delete() fscrypt_destroy_keyring() must be called after all potentially-encrypted inodes were evicted; otherwise it cannot safely destroy the keyring. Since inodes that are in-use by the Landlock LSM don't get evicted until security_sb_delete(), this means that fscrypt_destroy_keyring() must be called *after* security_sb_delete(). This fixes a WARN_ON followed by a NULL dereference, only possible if Landlock was being used on encrypted files.Show less

In the Linux kernel, the following vulnerability has been resolved: usb: ucsi: Fix NULL pointer deref in ucsi_connector_change() When ucsi_init() fails, ucsi->connector is NULL, yet in case of ucsi_acpi we may still get events which cause the ucs_acpi code to call ucsi_connector_change(), which then derefs the NULL ucsi->connector pointer. Fix this by not setting ucsi->ntfy inside ucsi_init() until ucsi_init() has succeeded, so that ucsi_connector_change() ignores the events because UCSI_ENABLE_NTFY_CONNECTOR_CHANGE is not set in the ntfy mask.Show less

In the Linux kernel, the following vulnerability has been resolved: dm stats: check for and propagate alloc_percpu failure Check alloc_precpu()'s return value and return an error from dm_stats_init() if it fails. Update alloc_dev() to fail if dm_stats_init() does. Otherwise, a NULL pointer dereference will occur in dm_stats_cleanup() even if dm-stats isn't being actively used.Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Check kzalloc() in lpfc_sli4_cgn_params_read() If kzalloc() fails in lpfc_sli4_cgn_params_read(), then we rely on lpfc_read_object()'s routine to NULL check pdata. Currently, an early return error is thrown from lpfc_read_object() to protect us from NULL ptr dereference, but the errno code is -ENODEV. Change the errno code to a more appropriate -ENOMEM.Show less

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 irqbypassShow less

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

In the Linux kernel, the following vulnerability has been resolved: RDMA/hns: Fix NULL pointer problem in free_mr_init() Lock grab occurs in a concurrent scenario, resulting in stepping on a NULL pointer. It should be init mutex_init() first before use the lock. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Call trace: __mutex_lock.constprop.0+0xd0/0x5c0 __mutex_lock_slowpath+0x1c/0x2c mutex_lock+0x44/0x50 free_mr_send_cmd_to_hw+0x7c/0x1c0 [hns_roce_hw_v2] hns_roce_v2_dereg_mr+0x30/0x40 [hns_roce_hw_v2] hns_roce_dereg_mr+0x4c/0x130 [hns_roce_hw_v2] ib_dereg_mr_user+0x54/0x124 uverbs_free_mr+0x24/0x30 destroy_hw_idr_uobject+0x38/0x74 uverbs_destroy_uobject+0x48/0x1c4 uobj_destroy+0x74/0xcc ib_uverbs_cmd_verbs+0x368/0xbb0 ib_uverbs_ioctl+0xec/0x1a4 __arm64_sys_ioctl+0xb4/0x100 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0x58/0x190 do_el0_svc+0x30/0x90 el0_svc+0x2c/0xb4 el0t_64_sync_handler+0x1a4/0x1b0 el0t_64_sync+0x19c/0x1a0Show less

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.Show less

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

In the Linux kernel, the following vulnerability has been resolved: rose: Fix NULL pointer dereference in rose_send_frame() The syzkaller reported an issue: KASAN: null-ptr-deref in range [0x0000000000000380-0x0000000000000387] CPU: 0 PID: 4069 Comm: kworker/0:15 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Workqueue: rcu_gp srcu_invoke_callbacks RIP: 0010:rose_send_frame+0x1dd/0x2f0 net/rose/rose_link.c:101 Call Trace: <IRQ> rose_transmit_clear_request+0x1d5/0x290 net/rose/rose_link.c:255 rose_rx_call_request+0x4c0/0x1bc0 net/rose/af_rose.c:1009 rose_loopback_timer+0x19e/0x590 net/rose/rose_loopback.c:111 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571 [...] </IRQ> It triggers NULL pointer dereference when 'neigh->dev->dev_addr' is called in the rose_send_frame(). It's the first occurrence of the `neigh` is in rose_loopback_timer() as `rose_loopback_neigh', and the 'dev' in 'rose_loopback_neigh' is initialized sa nullptr. It had been fixed by commit 3b3fd068c56e3fbea30090859216a368398e39bf ("rose: Fix Null pointer dereference in rose_send_frame()") ever. But it's introduced by commit 3c53cd65dece47dd1f9d3a809f32e59d1d87b2b8 ("rose: check NULL rose_loopback_neigh->loopback") again. We fix it by add NULL check in rose_transmit_clear_request(). When the 'dev' in 'neigh' is NULL, we don't reply the request and just clear it. syzkaller don't provide repro, and I provide a syz repro like: r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2) ioctl$sock_inet_SIOCSIFFLAGS(r0, 0x8914, &(0x7f0000000180)={'rose0\x00', 0x201}) r1 = syz_init_net_socket$rose(0xb, 0x5, 0x0) bind$rose(r1, &(0x7f00000000c0)=@full={0xb, @dev, @null, 0x0, [@null, @null, @netrom, @netrom, @default, @null]}, 0x40) connect$rose(r1, &(0x7f0000000240)=@short={0xb, @dev={0xbb, 0xbb, 0xbb, 0x1, 0x0}, @remote={0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0x1}, 0x1, @netrom={0xbb, 0xbb, 0xbb, 0xbb, 0xbb, 0x0, 0x0}}, 0x1c)Show less

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

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.Show less