In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none After grabbing q->sysfs_lock, q->elevator may become NULL because of elevator switch. Fix the NULL dereference on q->elevator by checking it with lock.

In the Linux kernel, the following vulnerability has been resolved: mm: memcg: fix NULL pointer in mem_cgroup_track_foreign_dirty_slowpath() As commit 18365225f044 ("hwpoison, memcg: forcibly uncharge LRU pages"), hwpoison will forcibly uncharg a LRU hwpoisoned page, the folio_memcg could be NULl, then, mem_cgroup_track_foreign_dirty_slowpath() could occurs a NULL pointer dereference, let's do not record the foreign writebacks for folio memcg is null in mem_cgroup_track_foreign_dirty() to fix it.

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.

In the Linux kernel, the following vulnerability has been resolved: bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent In some specific situations, the return value of __bch_btree_node_alloc may be NULL. This may lead to a potential NULL pointer dereference in caller function like a calling chain : btree_split->bch_btree_node_alloc->__bch_btree_node_alloc. Fix it by initializing the return value in __bch_btree_node_alloc.

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.

In the Linux kernel, the following vulnerability has been resolved: ovl: fix null pointer dereference in ovl_permission() Following process: P1 P2 path_lookupat link_path_walk inode_permission ovl_permission ovl_i_path_real(inode, &realpath) path->dentry = ovl_i_dentry_upper(inode) drop_cache __dentry_kill(ovl_dentry) iput(ovl_inode) ovl_destroy_inode(ovl_inode) dput(oi->__upperdentry) dentry_kill(upperdentry) dentry_unlink_inode upperdentry->d_inode = NULL realinode = d_inode(realpath.dentry) // return NULL inode_permission(realinode) inode->i_sb // NULL pointer dereference , will trigger an null pointer dereference at realinode: [ 335.664979] BUG: kernel NULL pointer dereference, address: 0000000000000002 [ 335.668032] CPU: 0 PID: 2592 Comm: ls Not tainted 6.3.0 [ 335.669956] RIP: 0010:inode_permission+0x33/0x2c0 [ 335.678939] Call Trace: [ 335.679165] <TASK> [ 335.679371] ovl_permission+0xde/0x320 [ 335.679723] inode_permission+0x15e/0x2c0 [ 335.680090] link_path_walk+0x115/0x550 [ 335.680771] path_lookupat.isra.0+0xb2/0x200 [ 335.681170] filename_lookup+0xda/0x240 [ 335.681922] vfs_statx+0xa6/0x1f0 [ 335.682233] vfs_fstatat+0x7b/0xb0 Fetch a reproducer in [Link]. Use the helper ovl_i_path_realinode() to get realinode and then do non-nullptr checking.

In the Linux kernel, the following vulnerability has been resolved: md/raid10: fix null-ptr-deref of mreplace in raid10_sync_request There are two check of 'mreplace' in raid10_sync_request(). In the first check, 'need_replace' will be set and 'mreplace' will be used later if no-Faulty 'mreplace' exists, In the second check, 'mreplace' will be set to NULL if it is Faulty, but 'need_replace' will not be changed accordingly. null-ptr-deref occurs if Faulty is set between two check. Fix it by merging two checks into one. And replace 'need_replace' with 'mreplace' because their values are always the same.

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.

In the Linux kernel, the following vulnerability has been resolved: efi: fix potential NULL deref in efi_mem_reserve_persistent When iterating on a linked list, a result of memremap is dereferenced without checking it for NULL. This patch adds a check that falls back on allocating a new page in case memremap doesn't succeed. Found by Linux Verification Center (linuxtesting.org) with SVACE. [ardb: return -ENOMEM instead of breaking out of the loop]

In the Linux kernel, the following vulnerability has been resolved: media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish() When the driver calls cx23885_risc_buffer() to prepare the buffer, the function call dma_alloc_coherent may fail, resulting in a empty buffer risc->cpu. Later when we free the buffer or access the buffer, null ptr deref is triggered. This bug is similar to the following one: https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71. We believe the bug can be also dynamically triggered from user side. Similarly, we fix this by checking the return value of cx23885_risc_buffer() and the value of risc->cpu before buffer free.

In the Linux kernel, the following vulnerability has been resolved: media: pci: cx23885: check cx23885_vdev_init() return cx23885_vdev_init() can return a NULL pointer, but that pointer is used in the next line without a check. Add a NULL pointer check and go to the error unwind if it is NULL.

In the Linux kernel, the following vulnerability has been resolved: nfc: nci: fix possible NULL pointer dereference in send_acknowledge() Handle memory allocation failure from nci_skb_alloc() (calling alloc_skb()) to avoid possible NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: ice: Block switchdev mode when ADQ is active and vice versa ADQ and switchdev are not supported simultaneously. Enabling both at the same time can result in nullptr dereference. To prevent this, check if ADQ is active when changing devlink mode to switchdev mode, and check if switchdev is active when enabling ADQ.

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: dp: Change logging to dev for mtk_dp_aux_transfer() Change logging from drm_{err,info}() to dev_{err,info}() in functions mtk_dp_aux_transfer() and mtk_dp_aux_do_transfer(): this will be essential to avoid getting NULL pointer kernel panics if any kind of error happens during AUX transfers happening before the bridge is attached. This may potentially start happening in a later commit implementing aux-bus support, as AUX transfers will be triggered from the panel driver (for EDID) before the mtk-dp bridge gets attached, and it's done in preparation for the same.

In the Linux kernel, the following vulnerability has been resolved: media: vsp1: Replace vb2_is_streaming() with vb2_start_streaming_called() The vsp1 driver uses the vb2_is_streaming() function in its .buf_queue() handler to check if the .start_streaming() operation has been called, and decide whether to just add the buffer to an internal queue, or also trigger a hardware run. vb2_is_streaming() relies on the vb2_queue structure's streaming field, which used to be set only after calling the .start_streaming() operation. Commit a10b21532574 ("media: vb2: add (un)prepare_streaming queue ops") changed this, setting the .streaming field in vb2_core_streamon() before enqueuing buffers to the driver and calling .start_streaming(). This broke the vsp1 driver which now believes that .start_streaming() has been called when it hasn't, leading to a crash: [ 881.058705] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020 [ 881.067495] Mem abort info: [ 881.070290] ESR = 0x0000000096000006 [ 881.074042] EC = 0x25: DABT (current EL), IL = 32 bits [ 881.079358] SET = 0, FnV = 0 [ 881.082414] EA = 0, S1PTW = 0 [ 881.085558] FSC = 0x06: level 2 translation fault [ 881.090439] Data abort info: [ 881.093320] ISV = 0, ISS = 0x00000006 [ 881.097157] CM = 0, WnR = 0 [ 881.100126] user pgtable: 4k pages, 48-bit VAs, pgdp=000000004fa51000 [ 881.106573] [0000000000000020] pgd=080000004f36e003, p4d=080000004f36e003, pud=080000004f7ec003, pmd=0000000000000000 [ 881.117217] Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP [ 881.123494] Modules linked in: rcar_fdp1 v4l2_mem2mem [ 881.128572] CPU: 0 PID: 1271 Comm: yavta Tainted: G B 6.2.0-rc1-00023-g6c94e2e99343 #556 [ 881.138061] Hardware name: Renesas Salvator-X 2nd version board based on r8a77965 (DT) [ 881.145981] pstate: 400000c5 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 881.152951] pc : vsp1_dl_list_add_body+0xa8/0xe0 [ 881.157580] lr : vsp1_dl_list_add_body+0x34/0xe0 [ 881.162206] sp : ffff80000c267710 [ 881.165522] x29: ffff80000c267710 x28: ffff000010938ae8 x27: ffff000013a8dd98 [ 881.172683] x26: ffff000010938098 x25: ffff000013a8dc00 x24: ffff000010ed6ba8 [ 881.179841] x23: ffff00000faa4000 x22: 0000000000000000 x21: 0000000000000020 [ 881.186998] x20: ffff00000faa4000 x19: 0000000000000000 x18: 0000000000000000 [ 881.194154] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 881.201309] x14: 0000000000000000 x13: 746e696174206c65 x12: ffff70000157043d [ 881.208465] x11: 1ffff0000157043c x10: ffff70000157043c x9 : dfff800000000000 [ 881.215622] x8 : ffff80000ab821e7 x7 : 00008ffffea8fbc4 x6 : 0000000000000001 [ 881.222779] x5 : ffff80000ab821e0 x4 : ffff70000157043d x3 : 0000000000000020 [ 881.229936] x2 : 0000000000000020 x1 : ffff00000e4f6400 x0 : 0000000000000000 [ 881.237092] Call trace: [ 881.239542] vsp1_dl_list_add_body+0xa8/0xe0 [ 881.243822] vsp1_video_pipeline_run+0x270/0x2a0 [ 881.248449] vsp1_video_buffer_queue+0x1c0/0x1d0 [ 881.253076] __enqueue_in_driver+0xbc/0x260 [ 881.257269] vb2_start_streaming+0x48/0x200 [ 881.261461] vb2_core_streamon+0x13c/0x280 [ 881.265565] vb2_streamon+0x3c/0x90 [ 881.269064] vsp1_video_streamon+0x2fc/0x3e0 [ 881.273344] v4l_streamon+0x50/0x70 [ 881.276844] __video_do_ioctl+0x2bc/0x5d0 [ 881.280861] video_usercopy+0x2a8/0xc80 [ 881.284704] video_ioctl2+0x20/0x40 [ 881.288201] v4l2_ioctl+0xa4/0xc0 [ 881.291525] __arm64_sys_ioctl+0xe8/0x110 [ 881.295543] invoke_syscall+0x68/0x190 [ 881.299303] el0_svc_common.constprop.0+0x88/0x170 [ 881.304105] do_el0_svc+0x4c/0xf0 [ 881.307430] el0_svc+0x4c/0xa0 [ 881.310494] el0t_64_sync_handler+0xbc/0x140 [ 881.314773] el0t_64_sync+0x190/0x194 [ 881.318450] Code: d50323bf d65f03c0 91008263 f9800071 (885f7c60) [ 881.324551] ---[ end trace 0000000000000000 ]--- [ 881.329173] note: yavta[1271] exited with preempt_count 1 A different r ---truncated---

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix null deref on element insertion There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem(): general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30 Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use.

In the Linux kernel, the following vulnerability has been resolved: wifi: iwl3945: Add missing check for create_singlethread_workqueue Add the check for the return value of the create_singlethread_workqueue in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: FS: JFS: Fix null-ptr-deref Read in txBegin Syzkaller reported an issue where txBegin may be called on a superblock in a read-only mounted filesystem which leads to NULL pointer deref. This could be solved by checking if the filesystem is read-only before calling txBegin, and returning with appropiate error code.

In the Linux kernel, the following vulnerability has been resolved: kobject: Add sanity check for kset->kobj.ktype in kset_register() When I register a kset in the following way: static struct kset my_kset; kobject_set_name(&my_kset.kobj, "my_kset"); ret = kset_register(&my_kset); A null pointer dereference exception is occurred: [ 4453.568337] Unable to handle kernel NULL pointer dereference at \ virtual address 0000000000000028 ... ... [ 4453.810361] Call trace: [ 4453.813062] kobject_get_ownership+0xc/0x34 [ 4453.817493] kobject_add_internal+0x98/0x274 [ 4453.822005] kset_register+0x5c/0xb4 [ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset] ... ... Because I didn't initialize my_kset.kobj.ktype. According to the description in Documentation/core-api/kobject.rst: - A ktype is the type of object that embeds a kobject. Every structure that embeds a kobject needs a corresponding ktype. So add sanity check to make sure kset->kobj.ktype is not NULL.

In the Linux kernel, the following vulnerability has been resolved: Drivers: vmbus: Check for channel allocation before looking up relids relid2channel() assumes vmbus channel array to be allocated when called. However, in cases such as kdump/kexec, not all relids will be reset by the host. When the second kernel boots and if the guest receives a vmbus interrupt during vmbus driver initialization before vmbus_connect() is called, before it finishes, or if it fails, the vmbus interrupt service routine is called which in turn calls relid2channel() and can cause a null pointer dereference. Print a warning and error out in relid2channel() for a channel id that's invalid in the second kernel.

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: dp: Only trigger DRM HPD events if bridge is attached The MediaTek DisplayPort interface bridge driver starts its interrupts as soon as its probed. However when the interrupts trigger the bridge might not have been attached to a DRM device. As drm_helper_hpd_irq_event() does not check whether the passed in drm_device is valid or not, a NULL pointer passed in results in a kernel NULL pointer dereference in it. Check whether the bridge is attached and only trigger an HPD event if it is.

In the Linux kernel, the following vulnerability has been resolved: regulator: da9063: better fix null deref with partial DT Two versions of the original patch were sent but V1 was merged instead of V2 due to a mistake. So update to V2. The advantage of V2 is that it completely avoids dereferencing the pointer, even just to take the address, which may fix problems with some compilers. Both versions work on my gcc 9.4 but use the safer one.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: drop redundant sched job cleanup when cs is aborted Once command submission failed due to userptr invalidation in amdgpu_cs_submit, legacy code will perform cleanup of scheduler job. However, it's not needed at all, as former commit has integrated job cleanup stuff into amdgpu_job_free. Otherwise, because of double free, a NULL pointer dereference will occur in such scenario. Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/2457

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.

In the Linux kernel, the following vulnerability has been resolved: scsi: iscsi_tcp: Check that sock is valid before iscsi_set_param() The validity of sock should be checked before assignment to avoid incorrect values. Commit 57569c37f0ad ("scsi: iscsi: iscsi_tcp: Fix null-ptr-deref while calling getpeername()") introduced this change which may lead to inconsistent values of tcp_sw_conn->sendpage and conn->datadgst_en. Fix the issue by moving the position of the assignment.

In the Linux kernel, the following vulnerability has been resolved: ALSA: ac97: Fix possible NULL dereference in snd_ac97_mixer smatch error: sound/pci/ac97/ac97_codec.c:2354 snd_ac97_mixer() error: we previously assumed 'rac97' could be null (see line 2072) remove redundant assignment, return error if rac97 is NULL.

In the Linux kernel, the following vulnerability has been resolved: net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler() When performing a stress test on SMC-R by rmmod mlx5_ib driver during the wrk/nginx test, we found that there is a probability of triggering a panic while terminating all link groups. This issue dues to the race between smc_smcr_terminate_all() and smc_buf_create(). smc_smcr_terminate_all smc_buf_create /* init */ conn->sndbuf_desc = NULL; ... __smc_lgr_terminate smc_conn_kill smc_close_abort smc_cdc_get_slot_and_msg_send __softirqentry_text_start smc_wr_tx_process_cqe smc_cdc_tx_handler READ(conn->sndbuf_desc->len); /* panic dues to NULL sndbuf_desc */ conn->sndbuf_desc = xxx; This patch tries to fix the issue by always to check the sndbuf_desc before send any cdc msg, to make sure that no null pointer is seen during cqe processing.

In the Linux kernel, the following vulnerability has been resolved: RDMA/cxgb4: Fix potential null-ptr-deref in pass_establish() If get_ep_from_tid() fails to lookup non-NULL value for ep, ep is dereferenced later regardless of whether it is empty. This patch adds a simple sanity check to fix the issue. Found by Linux Verification Center (linuxtesting.org) with SVACE.

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.

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: mtk_drm_crtc: 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: media: pci: tw68: Fix null-ptr-deref bug in buf prepare and finish When the driver calls tw68_risc_buffer() to prepare the buffer, the function call dma_alloc_coherent may fail, resulting in a empty buffer buf->cpu. Later when we free the buffer or access the buffer, null ptr deref is triggered. This bug is similar to the following one: https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71. We believe the bug can be also dynamically triggered from user side. Similarly, we fix this by checking the return value of tw68_risc_buffer() and the value of buf->cpu before buffer free.

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Pointer may be dereferenced Klocwork tool reported pointer 'rport' returned from call to function fc_bsg_to_rport() may be NULL and will be dereferenced. Add a fix to validate rport before dereferencing.

In the Linux kernel, the following vulnerability has been resolved: HID: betop: check shape of output reports betopff_init() only checks the total sum of the report counts for each report field to be at least 4, but hid_betopff_play() expects 4 report fields. A device advertising an output report with one field and 4 report counts would pass the check but crash the kernel with a NULL pointer dereference in hid_betopff_play().

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/0x84

In the Linux kernel, the following vulnerability has been resolved: net: phy: dp83822: Fix null pointer access on DP83825/DP83826 devices The probe() function is only used for the DP83822 PHY, leaving the private data pointer uninitialized for the smaller DP83825/26 models. While all uses of the private data structure are hidden in 82822 specific callbacks, configuring the interrupt is shared across all models. This causes a NULL pointer dereference on the smaller PHYs as it accesses the private data unchecked. Verifying the pointer avoids that.

In the Linux kernel, the following vulnerability has been resolved: erofs: fix wrong kunmap when using LZMA on HIGHMEM platforms As the call trace shown, the root cause is kunmap incorrect pages: BUG: kernel NULL pointer dereference, address: 00000000 CPU: 1 PID: 40 Comm: kworker/u5:0 Not tainted 6.2.0-rc5 #4 Workqueue: erofs_worker z_erofs_decompressqueue_work EIP: z_erofs_lzma_decompress+0x34b/0x8ac z_erofs_decompress+0x12/0x14 z_erofs_decompress_queue+0x7e7/0xb1c z_erofs_decompressqueue_work+0x32/0x60 process_one_work+0x24b/0x4d8 ? process_one_work+0x1a4/0x4d8 worker_thread+0x14c/0x3fc kthread+0xe6/0x10c ? rescuer_thread+0x358/0x358 ? kthread_complete_and_exit+0x18/0x18 ret_from_fork+0x1c/0x28 ---[ end trace 0000000000000000 ]--- The bug is trivial and should be fixed now. It has no impact on !HIGHMEM platforms.

In the Linux kernel, the following vulnerability has been resolved: drm/msm: another fix for the headless Adreno GPU Fix another oops reproducible when rebooting the board with the Adreno GPU working in the headless mode (e.g. iMX platforms). Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [00000000] *pgd=74936831, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] ARM CPU: 0 PID: 51 Comm: reboot Not tainted 6.2.0-rc1-dirty #11 Hardware name: Freescale i.MX53 (Device Tree Support) PC is at msm_atomic_commit_tail+0x50/0x970 LR is at commit_tail+0x9c/0x188 pc : [<c06aa430>] lr : [<c067a214>] psr: 600e0013 sp : e0851d30 ip : ee4eb7eb fp : 00090acc r10: 00000058 r9 : c2193014 r8 : c4310000 r7 : c4759380 r6 : 07bef61d r5 : 00000000 r4 : 00000000 r3 : c44cc440 r2 : 00000000 r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 74910019 DAC: 00000051 Register r0 information: NULL pointer Register r1 information: NULL pointer Register r2 information: NULL pointer Register r3 information: slab kmalloc-1k start c44cc400 pointer offset 64 size 1024 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: non-paged memory Register r7 information: slab kmalloc-128 start c4759380 pointer offset 0 size 128 Register r8 information: slab kmalloc-2k start c4310000 pointer offset 0 size 2048 Register r9 information: non-slab/vmalloc memory Register r10 information: non-paged memory Register r11 information: non-paged memory Register r12 information: non-paged memory Process reboot (pid: 51, stack limit = 0xc80046d9) Stack: (0xe0851d30 to 0xe0852000) 1d20: c4759380 fbd77200 000005ff 002b9c70 1d40: c4759380 c4759380 00000000 07bef61d 00000600 c0d6fe7c c2193014 00000058 1d60: 00090acc c067a214 00000000 c4759380 c4310000 00000000 c44cc854 c067a89c 1d80: 00000000 00000000 00000000 c4310468 00000000 c4759380 c4310000 c4310468 1da0: c4310470 c0643258 c4759380 00000000 00000000 c0c4ee24 00000000 c44cc810 1dc0: 00000000 c0c4ee24 00000000 c44cc810 00000000 0347d2a8 e0851e00 e0851e00 1de0: c4759380 c067ad20 c4310000 00000000 c44cc810 c27f8718 c44cc854 c067adb8 1e00: c4933000 00000002 00000001 00000000 00000000 c2130850 00000000 c2130854 1e20: c25fc488 00000000 c0ff162c 00000000 00000001 00000002 00000000 00000000 1e40: c43102c0 c43102c0 00000000 0347d2a8 c44cc810 c44cc814 c2133da8 c06d1a60 1e60: 00000000 00000000 00079028 c2012f24 fee1dead c4933000 00000058 c01431e4 1e80: 01234567 c0143a20 00000000 00000000 00000000 00000000 00000000 00000000 1ea0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1ec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1f00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1f20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1f40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1f60: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1f80: 00000000 00000000 00000000 0347d2a8 00000002 00000004 00000078 00000058 1fa0: c010028c c0100060 00000002 00000004 fee1dead 28121969 01234567 00079028 1fc0: 00000002 00000004 00000078 00000058 0002fdc5 00000000 00000000 00090acc 1fe0: 00000058 becc9c64 b6e97e05 b6e0e5f6 600e0030 fee1dead 00000000 00000000 msm_atomic_commit_tail from commit_tail+0x9c/0x188 commit_tail from drm_atomic_helper_commit+0x160/0x188 drm_atomic_helper_commit from drm_atomic_commit+0xac/0xe0 drm_atomic_commit from drm_atomic_helper_disable_all+0x1b0/0x1c0 drm_atomic_helper_disable_all from drm_atomic_helper_shutdown+0x88/0x140 drm_atomic_helper_shutdown from device_shutdown+0x16c/0x240 device_shutdown from kernel_restart+0x38/0x90 kernel_restart from __do_sys_reboot+0x ---truncated---

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.

In the Linux kernel, the following vulnerability has been resolved: btrfs: insert tree mod log move in push_node_left There is a fairly unlikely race condition in tree mod log rewind that can result in a kernel panic which has the following trace: [530.569] BTRFS critical (device sda3): unable to find logical 0 length 4096 [530.585] BTRFS critical (device sda3): unable to find logical 0 length 4096 [530.602] BUG: kernel NULL pointer dereference, address: 0000000000000002 [530.618] #PF: supervisor read access in kernel mode [530.629] #PF: error_code(0x0000) - not-present page [530.641] PGD 0 P4D 0 [530.647] Oops: 0000 [#1] SMP [530.654] CPU: 30 PID: 398973 Comm: below Kdump: loaded Tainted: G S O K 5.12.0-0_fbk13_clang_7455_gb24de3bdb045 #1 [530.680] Hardware name: Quanta Mono Lake-M.2 SATA 1HY9U9Z001G/Mono Lake-M.2 SATA, BIOS F20_3A15 08/16/2017 [530.703] RIP: 0010:__btrfs_map_block+0xaa/0xd00 [530.755] RSP: 0018:ffffc9002c2f7600 EFLAGS: 00010246 [530.767] RAX: ffffffffffffffea RBX: ffff888292e41000 RCX: f2702d8b8be15100 [530.784] RDX: ffff88885fda6fb8 RSI: ffff88885fd973c8 RDI: ffff88885fd973c8 [530.800] RBP: ffff888292e410d0 R08: ffffffff82fd7fd0 R09: 00000000fffeffff [530.816] R10: ffffffff82e57fd0 R11: ffffffff82e57d70 R12: 0000000000000000 [530.832] R13: 0000000000001000 R14: 0000000000001000 R15: ffffc9002c2f76f0 [530.848] FS: 00007f38d64af000(0000) GS:ffff88885fd80000(0000) knlGS:0000000000000000 [530.866] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [530.880] CR2: 0000000000000002 CR3: 00000002b6770004 CR4: 00000000003706e0 [530.896] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [530.912] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [530.928] Call Trace: [530.934] ? btrfs_printk+0x13b/0x18c [530.943] ? btrfs_bio_counter_inc_blocked+0x3d/0x130 [530.955] btrfs_map_bio+0x75/0x330 [530.963] ? kmem_cache_alloc+0x12a/0x2d0 [530.973] ? btrfs_submit_metadata_bio+0x63/0x100 [530.984] btrfs_submit_metadata_bio+0xa4/0x100 [530.995] submit_extent_page+0x30f/0x360 [531.004] read_extent_buffer_pages+0x49e/0x6d0 [531.015] ? submit_extent_page+0x360/0x360 [531.025] btree_read_extent_buffer_pages+0x5f/0x150 [531.037] read_tree_block+0x37/0x60 [531.046] read_block_for_search+0x18b/0x410 [531.056] btrfs_search_old_slot+0x198/0x2f0 [531.066] resolve_indirect_ref+0xfe/0x6f0 [531.076] ? ulist_alloc+0x31/0x60 [531.084] ? kmem_cache_alloc_trace+0x12e/0x2b0 [531.095] find_parent_nodes+0x720/0x1830 [531.105] ? ulist_alloc+0x10/0x60 [531.113] iterate_extent_inodes+0xea/0x370 [531.123] ? btrfs_previous_extent_item+0x8f/0x110 [531.134] ? btrfs_search_path_in_tree+0x240/0x240 [531.146] iterate_inodes_from_logical+0x98/0xd0 [531.157] ? btrfs_search_path_in_tree+0x240/0x240 [531.168] btrfs_ioctl_logical_to_ino+0xd9/0x180 [531.179] btrfs_ioctl+0xe2/0x2eb0 This occurs when logical inode resolution takes a tree mod log sequence number, and then while backref walking hits a rewind on a busy node which has the following sequence of tree mod log operations (numbers filled in from a specific example, but they are somewhat arbitrary) REMOVE_WHILE_FREEING slot 532 REMOVE_WHILE_FREEING slot 531 REMOVE_WHILE_FREEING slot 530 ... REMOVE_WHILE_FREEING slot 0 REMOVE slot 455 REMOVE slot 454 REMOVE slot 453 ... REMOVE slot 0 ADD slot 455 ADD slot 454 ADD slot 453 ... ADD slot 0 MOVE src slot 0 -> dst slot 456 nritems 533 REMOVE slot 455 REMOVE slot 454 REMOVE slot 453 ... REMOVE slot 0 When this sequence gets applied via btrfs_tree_mod_log_rewind, it allocates a fresh rewind eb, and first inserts the correct key info for the 533 elements, then overwrites the first 456 of them, then decrements the count by 456 via the add ops, then rewinds the move by doing a memmove from 456:988->0:532. We have never written anything past 532, ---truncated---

In the Linux kernel, the following vulnerability has been resolved: icmp6: Fix null-ptr-deref of ip6_null_entry->rt6i_idev in icmp6_dev(). With some IPv6 Ext Hdr (RPL, SRv6, etc.), we can send a packet that has the link-local address as src and dst IP and will be forwarded to an external IP in the IPv6 Ext Hdr. For example, the script below generates a packet whose src IP is the link-local address and dst is updated to 11::. # for f in $(find /proc/sys/net/ -name *seg6_enabled*); do echo 1 > $f; done # python3 >>> from socket import * >>> from scapy.all import * >>> >>> SRC_ADDR = DST_ADDR = "fe80::5054:ff:fe12:3456" >>> >>> pkt = IPv6(src=SRC_ADDR, dst=DST_ADDR) >>> pkt /= IPv6ExtHdrSegmentRouting(type=4, addresses=["11::", "22::"], segleft=1) >>> >>> sk = socket(AF_INET6, SOCK_RAW, IPPROTO_RAW) >>> sk.sendto(bytes(pkt), (DST_ADDR, 0)) For such a packet, we call ip6_route_input() to look up a route for the next destination in these three functions depending on the header type. * ipv6_rthdr_rcv() * ipv6_rpl_srh_rcv() * ipv6_srh_rcv() If no route is found, ip6_null_entry is set to skb, and the following dst_input(skb) calls ip6_pkt_drop(). Finally, in icmp6_dev(), we dereference skb_rt6_info(skb)->rt6i_idev->dev as the input device is the loopback interface. Then, we have to check if skb_rt6_info(skb)->rt6i_idev is NULL or not to avoid NULL pointer deref for ip6_null_entry. BUG: kernel NULL pointer dereference, address: 0000000000000000 PF: supervisor read access in kernel mode PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 157 Comm: python3 Not tainted 6.4.0-11996-gb121d614371c #35 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:icmp6_send (net/ipv6/icmp.c:436 net/ipv6/icmp.c:503) Code: fe ff ff 48 c7 40 30 c0 86 5d 83 e8 c6 44 1c 00 e9 c8 fc ff ff 49 8b 46 58 48 83 e0 fe 0f 84 4a fb ff ff 48 8b 80 d0 00 00 00 <48> 8b 00 44 8b 88 e0 00 00 00 e9 34 fb ff ff 4d 85 ed 0f 85 69 01 RSP: 0018:ffffc90000003c70 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 00000000000000e0 RDX: 0000000000000021 RSI: 0000000000000000 RDI: ffff888006d72a18 RBP: ffffc90000003d80 R08: 0000000000000000 R09: 0000000000000001 R10: ffffc90000003d98 R11: 0000000000000040 R12: ffff888006d72a10 R13: 0000000000000000 R14: ffff8880057fb800 R15: ffffffff835d86c0 FS: 00007f9dc72ee740(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000057b2000 CR4: 00000000007506f0 PKRU: 55555554 Call Trace: <IRQ> ip6_pkt_drop (net/ipv6/route.c:4513) ipv6_rthdr_rcv (net/ipv6/exthdrs.c:640 net/ipv6/exthdrs.c:686) ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:437 (discriminator 5)) ip6_input_finish (./include/linux/rcupdate.h:781 net/ipv6/ip6_input.c:483) __netif_receive_skb_one_core (net/core/dev.c:5455) process_backlog (./include/linux/rcupdate.h:781 net/core/dev.c:5895) __napi_poll (net/core/dev.c:6460) net_rx_action (net/core/dev.c:6529 net/core/dev.c:6660) __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554) do_softirq (kernel/softirq.c:454 kernel/softirq.c:441) </IRQ> <TASK> __local_bh_enable_ip (kernel/softirq.c:381) __dev_queue_xmit (net/core/dev.c:4231) ip6_finish_output2 (./include/net/neighbour.h:544 net/ipv6/ip6_output.c:135) rawv6_sendmsg (./include/net/dst.h:458 ./include/linux/netfilter.h:303 net/ipv6/raw.c:656 net/ipv6/raw.c:914) sock_sendmsg (net/socket.c:725 net/socket.c:748) __sys_sendto (net/socket.c:2134) __x64_sys_sendto (net/socket.c:2146 net/socket.c:2142 net/socket.c:2142) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) RIP: 0033:0x7f9dc751baea Code: d8 64 89 02 48 c7 c0 ff f ---truncated---

In the Linux kernel, the following vulnerability has been resolved: scsi: storvsc: Fix handling of virtual Fibre Channel timeouts Hyper-V provides the ability to connect Fibre Channel LUNs to the host system and present them in a guest VM as a SCSI device. I/O to the vFC device is handled by the storvsc driver. The storvsc driver includes a partial integration with the FC transport implemented in the generic portion of the Linux SCSI subsystem so that FC attributes can be displayed in /sys. However, the partial integration means that some aspects of vFC don't work properly. Unfortunately, a full and correct integration isn't practical because of limitations in what Hyper-V provides to the guest. In particular, in the context of Hyper-V storvsc, the FC transport timeout function fc_eh_timed_out() causes a kernel panic because it can't find the rport and dereferences a NULL pointer. The original patch that added the call from storvsc_eh_timed_out() to fc_eh_timed_out() is faulty in this regard. In many cases a timeout is due to a transient condition, so the situation can be improved by just continuing to wait like with other I/O requests issued by storvsc, and avoiding the guaranteed panic. For a permanent failure, continuing to wait may result in a hung thread instead of a panic, which again may be better. So fix the panic by removing the storvsc call to fc_eh_timed_out(). This allows storvsc to keep waiting for a response. The change has been tested by users who experienced a panic in fc_eh_timed_out() due to transient timeouts, and it solves their problem. In the future we may want to deprecate the vFC functionality in storvsc since it can't be fully fixed. But it has current users for whom it is working well enough, so it should probably stay for a while longer.

In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would treat an invalid group number as BUG(), since in theory it should never happen. However, if a malicious attaker (or fuzzer) modifies the superblock via the block device while it is the file system is mounted, it is possible for s_first_data_block to get set to a very large number. In that case, when calculating the block group of some block number (such as the starting block of a preallocation region), could result in an underflow and very large block group number. Then the BUG_ON check in ext4_get_group_info() would fire, resutling in a denial of service attack that can be triggered by root or someone with write access to the block device. For a quality of implementation perspective, it's best that even if the system administrator does something that they shouldn't, that it will not trigger a BUG. So instead of BUG'ing, ext4_get_group_info() will call ext4_error and return NULL. We also add fallback code in all of the callers of ext4_get_group_info() that it might NULL. Also, since ext4_get_group_info() was already borderline to be an inline function, un-inline it. The results in a next reduction of the compiled text size of ext4 by roughly 2k.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: check for null return of devm_kzalloc() in dpu_writeback_init() Because of the possilble failure of devm_kzalloc(), dpu_wb_conn might be NULL and will cause null pointer dereference later. Therefore, it might be better to check it and directly return -ENOMEM. Patchwork: https://patchwork.freedesktop.org/patch/512277/ [DB: fixed typo in commit message]

In the Linux kernel, the following vulnerability has been resolved: iw_cxgb4: Fix potential NULL dereference in c4iw_fill_res_cm_id_entry() This condition needs to match the previous "if (epcp->state == LISTEN) {" exactly to avoid a NULL dereference of either "listen_ep" or "ep". The problem is that "epcp" has been re-assigned so just testing "if (epcp->state == LISTEN) {" a second time is not sufficient.

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Fix potential NULL pointer dereference Klocwork tool reported 'cur_dsd' may be dereferenced. Add fix to validate pointer before dereferencing the pointer.

In the Linux kernel, the following vulnerability has been resolved: rcu: Protect rcu_print_task_exp_stall() ->exp_tasks access For kernels built with CONFIG_PREEMPT_RCU=y, the following scenario can result in a NULL-pointer dereference: CPU1 CPU2 rcu_preempt_deferred_qs_irqrestore rcu_print_task_exp_stall if (special.b.blocked) READ_ONCE(rnp->exp_tasks) != NULL raw_spin_lock_rcu_node np = rcu_next_node_entry(t, rnp) if (&t->rcu_node_entry == rnp->exp_tasks) WRITE_ONCE(rnp->exp_tasks, np) .... raw_spin_unlock_irqrestore_rcu_node raw_spin_lock_irqsave_rcu_node t = list_entry(rnp->exp_tasks->prev, struct task_struct, rcu_node_entry) (if rnp->exp_tasks is NULL, this will dereference a NULL pointer) The problem is that CPU2 accesses the rcu_node structure's->exp_tasks field without holding the rcu_node structure's ->lock and CPU2 did not observe CPU1's change to rcu_node structure's ->exp_tasks in time. Therefore, if CPU1 sets rcu_node structure's->exp_tasks pointer to NULL, then CPU2 might dereference that NULL pointer. This commit therefore holds the rcu_node structure's ->lock while accessing that structure's->exp_tasks field. [ paulmck: Apply Frederic Weisbecker feedback. ]

In the Linux kernel, the following vulnerability has been resolved: genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask() If ipi_send_{mask|single}() is called with an invalid interrupt number, all the local variables there will be NULL. ipi_send_verify() which is invoked from these functions does verify its 'data' parameter, resulting in a kernel oops in irq_data_get_affinity_mask() as the passed NULL pointer gets dereferenced. Add a missing NULL pointer check in ipi_send_verify()... Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool.

In the Linux kernel, the following vulnerability has been resolved: ACPI: processor: Check for null return of devm_kzalloc() in fch_misc_setup() devm_kzalloc() may fail, clk_data->name might be NULL and will cause a NULL pointer dereference later. [ rjw: Subject and changelog edits ]

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: install stub fence into potential unused fence pointers When using cpu to update page tables, vm update fences are unused. Install stub fence into these fence pointers instead of NULL to avoid NULL dereference when calling dma_fence_wait() on them.

In the Linux kernel, the following vulnerability has been resolved: media: bdisp: Add missing check for create_workqueue Add the check for the return value of the create_workqueue in order to avoid NULL pointer dereference.