NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Fix a null pointer crash in mtk_drm_crtc_finish_page_flip It's possible that mtk_crtc->event is NULL in mtk_drm_crtc_finish_page_flip(). pending_needs_vblank value is set by mtk_crtc->event, but in mtk_drm_crtc_atomic_flush(), it's is not guarded by the same lock in mtk_drm_finish_page_flip(), thus a race condition happens. Consider the following case: CPU1 CPU2 step 1: mtk_drm_crtc_atomic_begin() mtk_crtc->event is not null, step 1: mtk_drm_crtc_atomic_flush: mtk_drm_crtc_update_config( !!mtk_crtc->event) step 2: mtk_crtc_ddp_irq -> mtk_drm_finish_page_flip: lock mtk_crtc->event set to null, pending_needs_vblank set to false unlock pending_needs_vblank set to true, step 2: mtk_crtc_ddp_irq -> mtk_drm_finish_page_flip called again, pending_needs_vblank is still true //null pointer Instead of guarding the entire mtk_drm_crtc_atomic_flush(), it's more efficient to just check if mtk_crtc->event is null before use.Show less

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix NULL pointer dereference in f2fs_submit_page_write() BUG: kernel NULL pointer dereference, address: 0000000000000014 RIP: 0010:f2fs_submit_page_write+0x6cf/0x780 [f2fs] Call Trace: <TASK> ? show_regs+0x6e/0x80 ? __die+0x29/0x70 ? page_fault_oops+0x154/0x4a0 ? prb_read_valid+0x20/0x30 ? __irq_work_queue_local+0x39/0xd0 ? irq_work_queue+0x36/0x70 ? do_user_addr_fault+0x314/0x6c0 ? exc_page_fault+0x7d/0x190 ? asm_exc_page_fault+0x2b/0x30 ? f2fs_submit_page_write+0x6cf/0x780 [f2fs] ? f2fs_submit_page_write+0x736/0x780 [f2fs] do_write_page+0x50/0x170 [f2fs] f2fs_outplace_write_data+0x61/0xb0 [f2fs] f2fs_do_write_data_page+0x3f8/0x660 [f2fs] f2fs_write_single_data_page+0x5bb/0x7a0 [f2fs] f2fs_write_cache_pages+0x3da/0xbe0 [f2fs] ... It is possible that other threads have added this fio to io->bio and submitted the io->bio before entering f2fs_submit_page_write(). At this point io->bio = NULL. If is_end_zone_blkaddr(sbi, fio->new_blkaddr) of this fio is true, then an NULL pointer dereference error occurs at bio_get(io->bio). The original code for determining zone end was after "out:", which would have missed some fio who is zone end. I've moved this code before "skip:" to make sure it's done for each fio.Show less

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

In the Linux kernel, the following vulnerability has been resolved: comedi: comedi_8255: Correct error in subdevice initialization The refactoring done in commit 5c57b1ccecc7 ("comedi: comedi_8255: Rework subdevice initialization functions") to the initialization of the io field of struct subdev_8255_private broke all cards using the drivers/comedi/drivers/comedi_8255.c module. Prior to 5c57b1ccecc7, __subdev_8255_init() initialized the io field in the newly allocated struct subdev_8255_private to the non-NULL callback given to the function, otherwise it used a flag parameter to select between subdev_8255_mmio and subdev_8255_io. The refactoring removed that logic and the flag, as subdev_8255_mm_init() and subdev_8255_io_init() now explicitly pass subdev_8255_mmio and subdev_8255_io respectively to __subdev_8255_init(), only __subdev_8255_init() never sets spriv->io to the supplied callback. That spriv->io is NULL leads to a later BUG: BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0010 [#1] SMP PTI CPU: 1 PID: 1210 Comm: systemd-udevd Not tainted 6.7.3-x86_64 #1 Hardware name: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffa3f1c02d7b78 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff91f847aefd00 RCX: 000000000000009b RDX: 0000000000000003 RSI: 0000000000000001 RDI: ffff91f840f6fc00 RBP: ffff91f840f6fc00 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 000000000000005f R12: 0000000000000000 R13: 0000000000000000 R14: ffffffffc0102498 R15: ffff91f847ce6ba8 FS: 00007f72f4e8f500(0000) GS:ffff91f8d5c80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000010540e000 CR4: 00000000000406f0 Call Trace: <TASK> ? __die_body+0x15/0x57 ? page_fault_oops+0x2ef/0x33c ? insert_vmap_area.constprop.0+0xb6/0xd5 ? alloc_vmap_area+0x529/0x5ee ? exc_page_fault+0x15a/0x489 ? asm_exc_page_fault+0x22/0x30 __subdev_8255_init+0x79/0x8d [comedi_8255] pci_8255_auto_attach+0x11a/0x139 [8255_pci] comedi_auto_config+0xac/0x117 [comedi] ? __pfx___driver_attach+0x10/0x10 pci_device_probe+0x88/0xf9 really_probe+0x101/0x248 __driver_probe_device+0xbb/0xed driver_probe_device+0x1a/0x72 __driver_attach+0xd4/0xed bus_for_each_dev+0x76/0xb8 bus_add_driver+0xbe/0x1be driver_register+0x9a/0xd8 comedi_pci_driver_register+0x28/0x48 [comedi_pci] ? __pfx_pci_8255_driver_init+0x10/0x10 [8255_pci] do_one_initcall+0x72/0x183 do_init_module+0x5b/0x1e8 init_module_from_file+0x86/0xac __do_sys_finit_module+0x151/0x218 do_syscall_64+0x72/0xdb entry_SYSCALL_64_after_hwframe+0x6e/0x76 RIP: 0033:0x7f72f50a0cb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 47 71 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffd47e512d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 0000562dd06ae070 RCX: 00007f72f50a0cb9 RDX: 0000000000000000 RSI: 00007f72f52d32df RDI: 000000000000000e RBP: 0000000000000000 R08: 00007f72f5168b20 R09: 0000000000000000 R10: 0000000000000050 R11: 0000000000000246 R12: 00007f72f52d32df R13: 0000000000020000 R14: 0000562dd06785c0 R15: 0000562dcfd0e9a8 </TASK> Modules linked in: 8255_pci(+) comedi_8255 comedi_pci comedi intel_gtt e100(+) acpi_cpufreq rtc_cmos usbhid CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffa3f1c02d7b78 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff91f847aefd00 RCX: 000000000000009b RDX: 0000000000000003 RSI: 0000000000000001 RDI: ffff91f840f6fc00 RBP: ffff91f840f6fc00 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 000000000000005f R12: 0000000000000000 R13: 0000000000000000 R14: ffffffffc0102498 R15: ffff91f847ce6ba8 FS: ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Use a memory barrier to enforce PTP WQ xmit submission tracking occurs after populating the metadata_map Just simply reordering the functions mlx5e_ptp_metadata_map_put and mlx5e_ptpsq_track_metadata in the mlx5e_txwqe_complete context is not good enough since both the compiler and CPU are free to reorder these two functions. If reordering does occur, the issue that was supposedly fixed by 7e3f3ba97e6c ("net/mlx5e: Track xmit submission to PTP WQ after populating metadata map") will be seen. This will lead to NULL pointer dereferences in mlx5e_ptpsq_mark_ts_cqes_undelivered in the NAPI polling context due to the tracking list being populated before the metadata map.Show less

In the Linux kernel, the following vulnerability has been resolved: net: ice: Fix potential NULL pointer dereference in ice_bridge_setlink() The function ice_bridge_setlink() may encounter a NULL pointer dereference if nlmsg_find_attr() returns NULL and br_spec is dereferenced subsequently in nla_for_each_nested(). To address this issue, add a check to ensure that br_spec is not NULL before proceeding with the nested attribute iteration.Show less

In the Linux kernel, the following vulnerability has been resolved: ice: fix uninitialized dplls mutex usage The pf->dplls.lock mutex is initialized too late, after its first use. Move it to the top of ice_dpll_init. Note that the "err_exit" error path destroys the mutex. And the mutex is the last thing destroyed in ice_dpll_deinit. This fixes the following warning with CONFIG_DEBUG_MUTEXES: ice 0000:10:00.0: The DDP package was successfully loaded: ICE OS Default Package version 1.3.36.0 ice 0000:10:00.0: 252.048 Gb/s available PCIe bandwidth (16.0 GT/s PCIe x16 link) ice 0000:10:00.0: PTP init successful ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 0 PID: 410 at kernel/locking/mutex.c:587 __mutex_lock+0x773/0xd40 Modules linked in: crct10dif_pclmul crc32_pclmul crc32c_intel polyval_clmulni polyval_generic ice(+) nvme nvme_c> CPU: 0 PID: 410 Comm: kworker/0:4 Not tainted 6.8.0-rc5+ #3 Hardware name: HPE ProLiant DL110 Gen10 Plus/ProLiant DL110 Gen10 Plus, BIOS U56 10/19/2023 Workqueue: events work_for_cpu_fn RIP: 0010:__mutex_lock+0x773/0xd40 Code: c0 0f 84 1d f9 ff ff 44 8b 35 0d 9c 69 01 45 85 f6 0f 85 0d f9 ff ff 48 c7 c6 12 a2 a9 85 48 c7 c7 12 f1 a> RSP: 0018:ff7eb1a3417a7ae0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffffffff85ac2bff RDI: 00000000ffffffff RBP: ff7eb1a3417a7b80 R08: 0000000000000000 R09: 00000000ffffbfff R10: ff7eb1a3417a7978 R11: ff32b80f7fd2e568 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ff32b7f02c50e0d8 FS: 0000000000000000(0000) GS:ff32b80efe800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b5852cc000 CR3: 000000003c43a004 CR4: 0000000000771ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ? __warn+0x84/0x170 ? __mutex_lock+0x773/0xd40 ? report_bug+0x1c7/0x1d0 ? prb_read_valid+0x1b/0x30 ? handle_bug+0x42/0x70 ? exc_invalid_op+0x18/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? __mutex_lock+0x773/0xd40 ? rcu_is_watching+0x11/0x50 ? __kmalloc_node_track_caller+0x346/0x490 ? ice_dpll_lock_status_get+0x28/0x50 [ice] ? __pfx_ice_dpll_lock_status_get+0x10/0x10 [ice] ? ice_dpll_lock_status_get+0x28/0x50 [ice] ice_dpll_lock_status_get+0x28/0x50 [ice] dpll_device_get_one+0x14f/0x2e0 dpll_device_event_send+0x7d/0x150 dpll_device_register+0x124/0x180 ice_dpll_init_dpll+0x7b/0xd0 [ice] ice_dpll_init+0x224/0xa40 [ice] ? _dev_info+0x70/0x90 ice_load+0x468/0x690 [ice] ice_probe+0x75b/0xa10 [ice] ? _raw_spin_unlock_irqrestore+0x4f/0x80 ? process_one_work+0x1a3/0x500 local_pci_probe+0x47/0xa0 work_for_cpu_fn+0x17/0x30 process_one_work+0x20d/0x500 worker_thread+0x1df/0x3e0 ? __pfx_worker_thread+0x10/0x10 kthread+0x103/0x140 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> irq event stamp: 125197 hardirqs last enabled at (125197): [<ffffffff8416409d>] finish_task_switch.isra.0+0x12d/0x3d0 hardirqs last disabled at (125196): [<ffffffff85134044>] __schedule+0xea4/0x19f0 softirqs last enabled at (105334): [<ffffffff84e1e65a>] napi_get_frags_check+0x1a/0x60 softirqs last disabled at (105332): [<ffffffff84e1e65a>] napi_get_frags_check+0x1a/0x60 ---[ end trace 0000000000000000 ]---Show less

The memory allocation function ACPI_ALLOCATE_ZEROED does not guarantee a successful allocation, but the subsequent code directly dereferences the pointer that receives it, which may lead to null pointer dereference. To fix this issue, a null pointer check should be added. If it is null, return exception code AE_NO_MEMORY.Show less

net-snmp provides various tools relating to the Simple Network Management Protocol. Prior to version 5.9.2, a user with read-write credentials can use a malformed OID in a SET to the nsVacmAccessTable to cause a NULL pointer dereference. Version 5.9.2 contains a patch. Users should use strong SNMPv3 credentials and avoid sharing the credentials. Those who must use SNMPv1 or SNMPv2c should use a complex community string and enhance the protection by restricting access to a given IP address range. Show less

net-snmp provides various tools relating to the Simple Network Management Protocol. Prior to version 5.9.2, a user with read-only credentials can use a malformed OID in a `GET-NEXT` to the `nsVacmAccessTable` to cause a NULL pointer dereference. Version 5.9.2 contains a patch. Users should use strong SNMPv3 credentials and avoid sharing the credentials. Those who must use SNMPv1 or SNMPv2c should use a complex community string and enhance the protection by restricting access to a given IP address range. Show less

net-snmp provides various tools relating to the Simple Network Management Protocol. Prior to version 5.9.2, a user with read-write credentials can use a malformed OID in a `SET` request to `NET-SNMP-AGENT-MIB::nsLogTable` to cause a NULL pointer dereference. Version 5.9.2 contains a patch. Users should use strong SNMPv3 credentials and avoid sharing the credentials. Those who must use SNMPv1 or SNMPv2c should use a complex community string and enhance the protection by restricting access to a given IP address range. Show less

A NULL Pointer Dereference vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS). When Layer 2 traffic is sent through a logical interface, MAC learning happens. If during this process, the interface flaps, an Advanced Forwarding Toolkit manager (evo-aftmand-bt) core is observed. This leads to a PFE restart. The crash reoccurs if the same sequence of events happens, which will lead to a sustained DoS condition. This issue affects Juniper Networks Junos OS Evolved 23.2-EVO versions earlier than 23.2R1-S1-EVO, 23.2R2-EVO.Show less

Animate versions 23.0.4, 24.0.1 and earlier are affected by a NULL Pointer Dereference vulnerability that could lead to an application denial-of-service. An attacker could leverage this vulnerability to cause a system crash, resulting in a denial of service. Exploitation of this issue requires user interaction in that a victim must open a malicious file.Show less

In the Linux kernel, the following vulnerability has been resolved: selinux: fix NULL-pointer dereference when hashtab allocation fails When the hash table slot array allocation fails in hashtab_init(), h->size is left initialized with a non-zero value, but the h->htable pointer is NULL. This may then cause a NULL pointer dereference, since the policydb code relies on the assumption that even after a failed hashtab_init(), hashtab_map() and hashtab_destroy() can be safely called on it. Yet, these detect an empty hashtab only by looking at the size. Fix this by making sure that hashtab_init() always leaves behind a valid empty hashtab when the allocation fails.Show less

In the Linux kernel, the following vulnerability has been resolved: x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails Check for a valid hv_vp_index array prior to derefencing hv_vp_index when setting Hyper-V's TSC change callback. If Hyper-V setup failed in hyperv_init(), the kernel will still report that it's running under Hyper-V, but will have silently disabled nearly all functionality. BUG: kernel NULL pointer dereference, address: 0000000000000010 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:set_hv_tscchange_cb+0x15/0xa0 Code: <8b> 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08 ... Call Trace: kvm_arch_init+0x17c/0x280 kvm_init+0x31/0x330 vmx_init+0xba/0x13a do_one_initcall+0x41/0x1c0 kernel_init_freeable+0x1f2/0x23b kernel_init+0x16/0x120 ret_from_fork+0x22/0x30Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: fix null pointer dereference on pointer cs_desc The pointer cs_desc return from snd_usb_find_clock_source could be null, so there is a potential null pointer dereference issue. Fix this by adding a null check before dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: gus: fix null pointer dereference on pointer block The pointer block return from snd_gf1_dma_next_block could be null, so there is a potential null pointer dereference issue. Fix this by adding a null check before dereference.Show less