In the Linux kernel, the following vulnerability has been resolved: wifi: rtw89: coex: check NULL return of kmalloc in btc_fw_set_monreg() kmalloc may fail, return value might be NULL and will cause NULL pointer dereference. Add check NULL return of kmalloc in btc_fw_set_monreg().

In the Linux kernel, the following vulnerability has been resolved: wifi: ath10k: avoid NULL pointer error during sdio remove When running 'rmmod ath10k', ath10k_sdio_remove() will free sdio workqueue by destroy_workqueue(). But if CONFIG_INIT_ON_FREE_DEFAULT_ON is set to yes, kernel panic will happen: Call trace: destroy_workqueue+0x1c/0x258 ath10k_sdio_remove+0x84/0x94 sdio_bus_remove+0x50/0x16c device_release_driver_internal+0x188/0x25c device_driver_detach+0x20/0x2c This is because during 'rmmod ath10k', ath10k_sdio_remove() will call ath10k_core_destroy() before destroy_workqueue(). wiphy_dev_release() will finally be called in ath10k_core_destroy(). This function will free struct cfg80211_registered_device *rdev and all its members, including wiphy, dev and the pointer of sdio workqueue. Then the pointer of sdio workqueue will be set to NULL due to CONFIG_INIT_ON_FREE_DEFAULT_ON. After device release, destroy_workqueue() will use NULL pointer then the kernel panic happen. Call trace: ath10k_sdio_remove ->ath10k_core_unregister …… ->ath10k_core_stop ->ath10k_hif_stop ->ath10k_sdio_irq_disable ->ath10k_hif_power_down ->del_timer_sync(&ar_sdio->sleep_timer) ->ath10k_core_destroy ->ath10k_mac_destroy ->ieee80211_free_hw ->wiphy_free …… ->wiphy_dev_release ->destroy_workqueue Need to call destroy_workqueue() before ath10k_core_destroy(), free the work queue buffer first and then free pointer of work queue by ath10k_core_destroy(). This order matches the error path order in ath10k_sdio_probe(). No work will be queued on sdio workqueue between it is destroyed and ath10k_core_destroy() is called. Based on the call_stack above, the reason is: Only ath10k_sdio_sleep_timer_handler(), ath10k_sdio_hif_tx_sg() and ath10k_sdio_irq_disable() will queue work on sdio workqueue. Sleep timer will be deleted before ath10k_core_destroy() in ath10k_hif_power_down(). ath10k_sdio_irq_disable() only be called in ath10k_hif_stop(). ath10k_core_unregister() will call ath10k_hif_power_down() to stop hif bus, so ath10k_sdio_hif_tx_sg() won't be called anymore. Tested-on: QCA6174 hw3.2 SDIO WLAN.RMH.4.4.1-00189

In the Linux kernel, the following vulnerability has been resolved: udmabuf: change folios array from kmalloc to kvmalloc When PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine, page_alloc only support 4MB. If above this, trigger this warn and return NULL. udmabuf can change size limit, if change it to 3072(3GB), and then alloc 3GB udmabuf, will fail create. [ 4080.876581] ------------[ cut here ]------------ [ 4080.876843] WARNING: CPU: 3 PID: 2015 at mm/page_alloc.c:4556 __alloc_pages+0x2c8/0x350 [ 4080.878839] RIP: 0010:__alloc_pages+0x2c8/0x350 [ 4080.879470] Call Trace: [ 4080.879473] <TASK> [ 4080.879473] ? __alloc_pages+0x2c8/0x350 [ 4080.879475] ? __warn.cold+0x8e/0xe8 [ 4080.880647] ? __alloc_pages+0x2c8/0x350 [ 4080.880909] ? report_bug+0xff/0x140 [ 4080.881175] ? handle_bug+0x3c/0x80 [ 4080.881556] ? exc_invalid_op+0x17/0x70 [ 4080.881559] ? asm_exc_invalid_op+0x1a/0x20 [ 4080.882077] ? udmabuf_create+0x131/0x400 Because MAX_PAGE_ORDER, kmalloc can max alloc 4096 * (1 << 10), 4MB memory, each array entry is pointer(8byte), so can save 524288 pages(2GB). Further more, costly order(order 3) may not be guaranteed that it can be applied for, due to fragmentation. This patch change udmabuf array use kvmalloc_array, this can fallback alloc into vmalloc, which can guarantee allocation for any size and does not affect the performance of kmalloc allocations.

In the Linux kernel, the following vulnerability has been resolved: ipv6: avoid possible NULL deref in modify_prefix_route() syzbot found a NULL deref [1] in modify_prefix_route(), caused by one fib6_info without a fib6_table pointer set. This can happen for net->ipv6.fib6_null_entry [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 1 UID: 0 PID: 5837 Comm: syz-executor888 Not tainted 6.12.0-syzkaller-09567-g7eef7e306d3c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__lock_acquire+0xe4/0x3c40 kernel/locking/lockdep.c:5089 Code: 08 84 d2 0f 85 15 14 00 00 44 8b 0d ca 98 f5 0e 45 85 c9 0f 84 b4 0e 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 96 2c 00 00 49 8b 04 24 48 3d a0 07 7f 93 0f 84 RSP: 0018:ffffc900035d7268 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000006 RSI: 1ffff920006bae5f RDI: 0000000000000030 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90608e17 R11: 0000000000000001 R12: 0000000000000030 R13: ffff888036334880 R14: 0000000000000000 R15: 0000000000000000 FS: 0000555579e90380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc59cc4278 CR3: 0000000072b54000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] modify_prefix_route+0x30b/0x8b0 net/ipv6/addrconf.c:4831 inet6_addr_modify net/ipv6/addrconf.c:4923 [inline] inet6_rtm_newaddr+0x12c7/0x1ab0 net/ipv6/addrconf.c:5055 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6920 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2541 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2583 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2637 __sys_sendmsg+0x16e/0x220 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd1dcef8b79 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc59cc4378 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd1dcef8b79 RDX: 0000000000040040 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 00000000000113fd R08: 0000000000000006 R09: 0000000000000006 R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffc59cc438c R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001 </TASK>

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix oops due to NULL pointer dereference in brcmf_sdiod_sglist_rw() This patch fixes a NULL pointer dereference bug in brcmfmac that occurs when a high 'sd_sgentry_align' value applies (e.g. 512) and a lot of queued SKBs are sent from the pkt queue. The problem is the number of entries in the pre-allocated sgtable, it is nents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) >> 4 + 1. Given the default [rt]xglom_size=32 it's actually 35 which is too small. Worst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB is added for each original SKB if tailroom isn't enough to hold tail_pad. At least one sg entry is needed for each SKB. So, eventually the "skb_queue_walk loop" in brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return NULL and this causes the oops. The patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle the worst-case. Btw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464 additional bytes of memory.

In the Linux kernel, the following vulnerability has been resolved: media: ts2020: fix null-ptr-deref in ts2020_probe() KASAN reported a null-ptr-deref issue when executing the following command: # echo ts2020 0x20 > /sys/bus/i2c/devices/i2c-0/new_device KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 53 UID: 0 PID: 970 Comm: systemd-udevd Not tainted 6.12.0-rc2+ #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) RIP: 0010:ts2020_probe+0xad/0xe10 [ts2020] RSP: 0018:ffffc9000abbf598 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffffc0714809 RDX: 0000000000000002 RSI: ffff88811550be00 RDI: 0000000000000010 RBP: ffff888109868800 R08: 0000000000000001 R09: fffff52001577eb6 R10: 0000000000000000 R11: ffffc9000abbff50 R12: ffffffffc0714790 R13: 1ffff92001577eb8 R14: ffffffffc07190d0 R15: 0000000000000001 FS: 00007f95f13b98c0(0000) GS:ffff888149280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555d2634b000 CR3: 0000000152236000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ts2020_probe+0xad/0xe10 [ts2020] i2c_device_probe+0x421/0xb40 really_probe+0x266/0x850 ... The cause of the problem is that when using sysfs to dynamically register an i2c device, there is no platform data, but the probe process of ts2020 needs to use platform data, resulting in a null pointer being accessed. Solve this problem by adding checks to platform data.

In the Linux kernel, the following vulnerability has been resolved: ftrace: Fix regression with module command in stack_trace_filter When executing the following command: # echo "write*:mod:ext3" > /sys/kernel/tracing/stack_trace_filter The current mod command causes a null pointer dereference. While commit 0f17976568b3f ("ftrace: Fix regression with module command in stack_trace_filter") has addressed part of the issue, it left a corner case unhandled, which still results in a kernel crash.

In the Linux kernel, the following vulnerability has been resolved: leds: class: Protect brightness_show() with led_cdev->led_access mutex There is NULL pointer issue observed if from Process A where hid device being added which results in adding a led_cdev addition and later a another call to access of led_cdev attribute from Process B can result in NULL pointer issue. Use mutex led_cdev->led_access to protect access to led->cdev and its attribute inside brightness_show() and max_brightness_show() and also update the comment for mutex that it should be used to protect the led class device fields. Process A Process B kthread+0x114 worker_thread+0x244 process_scheduled_works+0x248 uhid_device_add_worker+0x24 hid_add_device+0x120 device_add+0x268 bus_probe_device+0x94 device_initial_probe+0x14 __device_attach+0xfc bus_for_each_drv+0x10c __device_attach_driver+0x14c driver_probe_device+0x3c __driver_probe_device+0xa0 really_probe+0x190 hid_device_probe+0x130 ps_probe+0x990 ps_led_register+0x94 devm_led_classdev_register_ext+0x58 led_classdev_register_ext+0x1f8 device_create_with_groups+0x48 device_create_groups_vargs+0xc8 device_add+0x244 kobject_uevent+0x14 kobject_uevent_env[jt]+0x224 mutex_unlock[jt]+0xc4 __mutex_unlock_slowpath+0xd4 wake_up_q+0x70 try_to_wake_up[jt]+0x48c preempt_schedule_common+0x28 __schedule+0x628 __switch_to+0x174 el0t_64_sync+0x1a8/0x1ac el0t_64_sync_handler+0x68/0xbc el0_svc+0x38/0x68 do_el0_svc+0x1c/0x28 el0_svc_common+0x80/0xe0 invoke_syscall+0x58/0x114 __arm64_sys_read+0x1c/0x2c ksys_read+0x78/0xe8 vfs_read+0x1e0/0x2c8 kernfs_fop_read_iter+0x68/0x1b4 seq_read_iter+0x158/0x4ec kernfs_seq_show+0x44/0x54 sysfs_kf_seq_show+0xb4/0x130 dev_attr_show+0x38/0x74 brightness_show+0x20/0x4c dualshock4_led_get_brightness+0xc/0x74 [ 3313.874295][ T4013] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060 [ 3313.874301][ T4013] Mem abort info: [ 3313.874303][ T4013] ESR = 0x0000000096000006 [ 3313.874305][ T4013] EC = 0x25: DABT (current EL), IL = 32 bits [ 3313.874307][ T4013] SET = 0, FnV = 0 [ 3313.874309][ T4013] EA = 0, S1PTW = 0 [ 3313.874311][ T4013] FSC = 0x06: level 2 translation fault [ 3313.874313][ T4013] Data abort info: [ 3313.874314][ T4013] ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 [ 3313.874316][ T4013] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 3313.874318][ T4013] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 3313.874320][ T4013] user pgtable: 4k pages, 39-bit VAs, pgdp=00000008f2b0a000 .. [ 3313.874332][ T4013] Dumping ftrace buffer: [ 3313.874334][ T4013] (ftrace buffer empty) .. .. [ dd3313.874639][ T4013] CPU: 6 PID: 4013 Comm: InputReader [ 3313.874648][ T4013] pc : dualshock4_led_get_brightness+0xc/0x74 [ 3313.874653][ T4013] lr : led_update_brightness+0x38/0x60 [ 3313.874656][ T4013] sp : ffffffc0b910bbd0 .. .. [ 3313.874685][ T4013] Call trace: [ 3313.874687][ T4013] dualshock4_led_get_brightness+0xc/0x74 [ 3313.874690][ T4013] brightness_show+0x20/0x4c [ 3313.874692][ T4013] dev_attr_show+0x38/0x74 [ 3313.874696][ T4013] sysfs_kf_seq_show+0xb4/0x130 [ 3313.874700][ T4013] kernfs_seq_show+0x44/0x54 [ 3313.874703][ T4013] seq_read_iter+0x158/0x4ec [ 3313.874705][ T4013] kernfs_fop_read_iter+0x68/0x1b4 [ 3313.874708][ T4013] vfs_read+0x1e0/0x2c8 [ 3313.874711][ T4013] ksys_read+0x78/0xe8 [ 3313.874714][ T4013] __arm64_sys_read+0x1c/0x2c [ 3313.874718][ T4013] invoke_syscall+0x58/0x114 [ 3313.874721][ T4013] el0_svc_common+0x80/0xe0 [ 3313.874724][ T4013] do_el0_svc+0x1c/0x28 [ 3313.874727][ T4013] el0_svc+0x38/0x68 [ 3313.874730][ T4013] el0t_64_sync_handler+0x68/0xbc [ 3313.874732][ T4013] el0t_64_sync+0x1a8/0x1ac

In the Linux kernel, the following vulnerability has been resolved: dmaengine: at_xdmac: avoid null_prt_deref in at_xdmac_prep_dma_memset The at_xdmac_memset_create_desc may return NULL, which will lead to a null pointer dereference. For example, the len input is error, or the atchan->free_descs_list is empty and memory is exhausted. Therefore, add check to avoid this.

In the Linux kernel, the following vulnerability has been resolved: media: wl128x: Fix atomicity violation in fmc_send_cmd() Atomicity violation occurs when the fmc_send_cmd() function is executed simultaneously with the modification of the fmdev->resp_skb value. Consider a scenario where, after passing the validity check within the function, a non-null fmdev->resp_skb variable is assigned a null value. This results in an invalid fmdev->resp_skb variable passing the validity check. As seen in the later part of the function, skb = fmdev->resp_skb; when the invalid fmdev->resp_skb passes the check, a null pointer dereference error may occur at line 478, evt_hdr = (void *)skb->data; To address this issue, it is recommended to include the validity check of fmdev->resp_skb within the locked section of the function. This modification ensures that the value of fmdev->resp_skb does not change during the validation process, thereby maintaining its validity. This possible bug is found by an experimental static analysis tool developed by our team. This tool analyzes the locking APIs to extract function pairs that can be concurrently executed, and then analyzes the instructions in the paired functions to identify possible concurrency bugs including data races and atomicity violations.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix the memory allocation issue in amdgpu_discovery_get_nps_info() Fix two issues with memory allocation in amdgpu_discovery_get_nps_info() for mem_ranges: - Add a check for allocation failure to avoid dereferencing a null pointer. - As suggested by Christophe, use kvcalloc() for memory allocation, which checks for multiplication overflow. Additionally, assign the output parameters nps_type and range_cnt after the kvcalloc() call to prevent modifying the output parameters in case of an error return.

In the Linux kernel, the following vulnerability has been resolved: tipc: fix NULL deref in cleanup_bearer() syzbot found [1] that after blamed commit, ub->ubsock->sk was NULL when attempting the atomic_dec() : atomic_dec(&tipc_net(sock_net(ub->ubsock->sk))->wq_count); Fix this by caching the tipc_net pointer. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 0 UID: 0 PID: 5896 Comm: kworker/0:3 Not tainted 6.13.0-rc1-next-20241203-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events cleanup_bearer RIP: 0010:read_pnet include/net/net_namespace.h:387 [inline] RIP: 0010:sock_net include/net/sock.h:655 [inline] RIP: 0010:cleanup_bearer+0x1f7/0x280 net/tipc/udp_media.c:820 Code: 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 3c f7 99 f6 48 8b 1b 48 83 c3 30 e8 f0 e4 60 00 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 1a f7 99 f6 49 83 c7 e8 48 8b 1b RSP: 0018:ffffc9000410fb70 EFLAGS: 00010206 RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88802fe45a00 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410f900 RBP: ffff88807e1f0908 R08: ffffc9000410f907 R09: 1ffff92000821f20 R10: dffffc0000000000 R11: fffff52000821f21 R12: ffff888031d19980 R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807e1f0918 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556ca050b000 CR3: 0000000031c0c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

In the Linux kernel, the following vulnerability has been resolved: octeontx2-pf: handle otx2_mbox_get_rsp errors in cn10k.c Add error pointer check after calling otx2_mbox_get_rsp().

In the Linux kernel, the following vulnerability has been resolved: erofs: fix file-backed mounts over FUSE syzbot reported a null-ptr-deref in fuse_read_args_fill: fuse_read_folio+0xb0/0x100 fs/fuse/file.c:905 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2367 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3825 read_mapping_folio include/linux/pagemap.h:1011 [inline] erofs_bread+0x34d/0x7e0 fs/erofs/data.c:41 erofs_read_superblock fs/erofs/super.c:281 [inline] erofs_fc_fill_super+0x2b9/0x2500 fs/erofs/super.c:625 Unlike most filesystems, some network filesystems and FUSE need unavoidable valid `file` pointers for their read I/Os [1]. Anyway, those use cases need to be supported too. [1] https://docs.kernel.org/filesystems/vfs.html

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: gadget: Fix looping of queued SG entries The dwc3_request->num_queued_sgs is decremented on completion. If a partially completed request is handled, then the dwc3_request->num_queued_sgs no longer reflects the total number of num_queued_sgs (it would be cleared). Correctly check the number of request SG entries remained to be prepare and queued. Failure to do this may cause null pointer dereference when accessing non-existent SG entry.

In the Linux kernel, the following vulnerability has been resolved: bpf: Mark raw_tp arguments with PTR_MAYBE_NULL Arguments to a raw tracepoint are tagged as trusted, which carries the semantics that the pointer will be non-NULL. However, in certain cases, a raw tracepoint argument may end up being NULL. More context about this issue is available in [0]. Thus, there is a discrepancy between the reality, that raw_tp arguments can actually be NULL, and the verifier's knowledge, that they are never NULL, causing explicit NULL checks to be deleted, and accesses to such pointers potentially crashing the kernel. To fix this, mark raw_tp arguments as PTR_MAYBE_NULL, and then special case the dereference and pointer arithmetic to permit it, and allow passing them into helpers/kfuncs; these exceptions are made for raw_tp programs only. Ensure that we don't do this when ref_obj_id > 0, as in that case this is an acquired object and doesn't need such adjustment. The reason we do mask_raw_tp_trusted_reg logic is because other will recheck in places whether the register is a trusted_reg, and then consider our register as untrusted when detecting the presence of the PTR_MAYBE_NULL flag. To allow safe dereference, we enable PROBE_MEM marking when we see loads into trusted pointers with PTR_MAYBE_NULL. While trusted raw_tp arguments can also be passed into helpers or kfuncs where such broken assumption may cause issues, a future patch set will tackle their case separately, as PTR_TO_BTF_ID (without PTR_TRUSTED) can already be passed into helpers and causes similar problems. Thus, they are left alone for now. It is possible that these checks also permit passing non-raw_tp args that are trusted PTR_TO_BTF_ID with null marking. In such a case, allowing dereference when pointer is NULL expands allowed behavior, so won't regress existing programs, and the case of passing these into helpers is the same as above and will be dealt with later. Also update the failure case in tp_btf_nullable selftest to capture the new behavior, as the verifier will no longer cause an error when directly dereference a raw tracepoint argument marked as __nullable. [0]: https://lore.kernel.org/bpf/ZrCZS6nisraEqehw@jlelli-thinkpadt14gen4.remote.csb

In the Linux kernel, the following vulnerability has been resolved: cacheinfo: Allocate memory during CPU hotplug if not done from the primary CPU Commit 5944ce092b97 ("arch_topology: Build cacheinfo from primary CPU") adds functionality that architectures can use to optionally allocate and build cacheinfo early during boot. Commit 6539cffa9495 ("cacheinfo: Add arch specific early level initializer") lets secondary CPUs correct (and reallocate memory) cacheinfo data if needed. If the early build functionality is not used and cacheinfo does not need correction, memory for cacheinfo is never allocated. x86 does not use the early build functionality. Consequently, during the cacheinfo CPU hotplug callback, last_level_cache_is_valid() attempts to dereference a NULL pointer: BUG: kernel NULL pointer dereference, address: 0000000000000100 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not present page PGD 0 P4D 0 Oops: 0000 [#1] PREEPMT SMP NOPTI CPU: 0 PID 19 Comm: cpuhp/0 Not tainted 6.4.0-rc2 #1 RIP: 0010: last_level_cache_is_valid+0x95/0xe0a Allocate memory for cacheinfo during the cacheinfo CPU hotplug callback if not done earlier. Moreover, before determining the validity of the last-level cache info, ensure that it has been allocated. Simply checking for non-zero cache_leaves() is not sufficient, as some architectures (e.g., Intel processors) have non-zero cache_leaves() before allocation. Dereferencing NULL cacheinfo can occur in update_per_cpu_data_slice_size(). This function iterates over all online CPUs. However, a CPU may have come online recently, but its cacheinfo may not have been allocated yet. While here, remove an unnecessary indentation in allocate_cache_info(). [ bp: Massage. ]

In the Linux kernel, the following vulnerability has been resolved: media: mtk-jpeg: Fix null-ptr-deref during unload module The workqueue should be destroyed in mtk_jpeg_core.c since commit 09aea13ecf6f ("media: mtk-jpeg: refactor some variables"), otherwise the below calltrace can be easily triggered. [ 677.862514] Unable to handle kernel paging request at virtual address dfff800000000023 [ 677.863633] KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f] ... [ 677.879654] CPU: 6 PID: 1071 Comm: modprobe Tainted: G O 6.8.12-mtk+gfa1a78e5d24b+ #17 ... [ 677.882838] pc : destroy_workqueue+0x3c/0x770 [ 677.883413] lr : mtk_jpegdec_destroy_workqueue+0x70/0x88 [mtk_jpeg_dec_hw] [ 677.884314] sp : ffff80008ad974f0 [ 677.884744] x29: ffff80008ad974f0 x28: ffff0000d7115580 x27: ffff0000dd691070 [ 677.885669] x26: ffff0000dd691408 x25: ffff8000844af3e0 x24: ffff80008ad97690 [ 677.886592] x23: ffff0000e051d400 x22: ffff0000dd691010 x21: dfff800000000000 [ 677.887515] x20: 0000000000000000 x19: 0000000000000000 x18: ffff800085397ac0 [ 677.888438] x17: 0000000000000000 x16: ffff8000801b87c8 x15: 1ffff000115b2e10 [ 677.889361] x14: 00000000f1f1f1f1 x13: 0000000000000000 x12: ffff7000115b2e4d [ 677.890285] x11: 1ffff000115b2e4c x10: ffff7000115b2e4c x9 : ffff80000aa43e90 [ 677.891208] x8 : 00008fffeea4d1b4 x7 : ffff80008ad97267 x6 : 0000000000000001 [ 677.892131] x5 : ffff80008ad97260 x4 : ffff7000115b2e4d x3 : 0000000000000000 [ 677.893054] x2 : 0000000000000023 x1 : dfff800000000000 x0 : 0000000000000118 [ 677.893977] Call trace: [ 677.894297] destroy_workqueue+0x3c/0x770 [ 677.894826] mtk_jpegdec_destroy_workqueue+0x70/0x88 [mtk_jpeg_dec_hw] [ 677.895677] devm_action_release+0x50/0x90 [ 677.896211] release_nodes+0xe8/0x170 [ 677.896688] devres_release_all+0xf8/0x178 [ 677.897219] device_unbind_cleanup+0x24/0x170 [ 677.897785] device_release_driver_internal+0x35c/0x480 [ 677.898461] device_release_driver+0x20/0x38 ... [ 677.912665] ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: mm/gup: handle NULL pages in unpin_user_pages() The recent addition of "pofs" (pages or folios) handling to gup has a flaw: it assumes that unpin_user_pages() handles NULL pages in the pages** array. That's not the case, as I discovered when I ran on a new configuration on my test machine. Fix this by skipping NULL pages in unpin_user_pages(), just like unpin_folios() already does. Details: when booting on x86 with "numa=fake=2 movablecore=4G" on Linux 6.12, and running this: tools/testing/selftests/mm/gup_longterm ...I get the following crash: BUG: kernel NULL pointer dereference, address: 0000000000000008 RIP: 0010:sanity_check_pinned_pages+0x3a/0x2d0 ... Call Trace: <TASK> ? __die_body+0x66/0xb0 ? page_fault_oops+0x30c/0x3b0 ? do_user_addr_fault+0x6c3/0x720 ? irqentry_enter+0x34/0x60 ? exc_page_fault+0x68/0x100 ? asm_exc_page_fault+0x22/0x30 ? sanity_check_pinned_pages+0x3a/0x2d0 unpin_user_pages+0x24/0xe0 check_and_migrate_movable_pages_or_folios+0x455/0x4b0 __gup_longterm_locked+0x3bf/0x820 ? mmap_read_lock_killable+0x12/0x50 ? __pfx_mmap_read_lock_killable+0x10/0x10 pin_user_pages+0x66/0xa0 gup_test_ioctl+0x358/0xb20 __se_sys_ioctl+0x6b/0xc0 do_syscall_64+0x7b/0x150 entry_SYSCALL_64_after_hwframe+0x76/0x7e

In the Linux kernel, the following vulnerability has been resolved: media: imx-jpeg: Ensure power suppliers be suspended before detach them The power suppliers are always requested to suspend asynchronously, dev_pm_domain_detach() requires the caller to ensure proper synchronization of this function with power management callbacks. otherwise the detach may led to kernel panic, like below: [ 1457.107934] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000040 [ 1457.116777] Mem abort info: [ 1457.119589] ESR = 0x0000000096000004 [ 1457.123358] EC = 0x25: DABT (current EL), IL = 32 bits [ 1457.128692] SET = 0, FnV = 0 [ 1457.131764] EA = 0, S1PTW = 0 [ 1457.134920] FSC = 0x04: level 0 translation fault [ 1457.139812] Data abort info: [ 1457.142707] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 1457.148196] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 1457.153256] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 1457.158563] user pgtable: 4k pages, 48-bit VAs, pgdp=00000001138b6000 [ 1457.165000] [0000000000000040] pgd=0000000000000000, p4d=0000000000000000 [ 1457.171792] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 1457.178045] Modules linked in: v4l2_jpeg wave6_vpu_ctrl(-) [last unloaded: mxc_jpeg_encdec] [ 1457.186383] CPU: 0 PID: 51938 Comm: kworker/0:3 Not tainted 6.6.36-gd23d64eea511 #66 [ 1457.194112] Hardware name: NXP i.MX95 19X19 board (DT) [ 1457.199236] Workqueue: pm pm_runtime_work [ 1457.203247] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1457.210188] pc : genpd_runtime_suspend+0x20/0x290 [ 1457.214886] lr : __rpm_callback+0x48/0x1d8 [ 1457.218968] sp : ffff80008250bc50 [ 1457.222270] x29: ffff80008250bc50 x28: 0000000000000000 x27: 0000000000000000 [ 1457.229394] x26: 0000000000000000 x25: 0000000000000008 x24: 00000000000f4240 [ 1457.236518] x23: 0000000000000000 x22: ffff00008590f0e4 x21: 0000000000000008 [ 1457.243642] x20: ffff80008099c434 x19: ffff00008590f000 x18: ffffffffffffffff [ 1457.250766] x17: 5300326563697665 x16: 645f676e696c6f6f x15: 63343a6d726f6674 [ 1457.257890] x14: 0000000000000004 x13: 00000000000003a4 x12: 0000000000000002 [ 1457.265014] x11: 0000000000000000 x10: 0000000000000a60 x9 : ffff80008250bbb0 [ 1457.272138] x8 : ffff000092937200 x7 : ffff0003fdf6af80 x6 : 0000000000000000 [ 1457.279262] x5 : 00000000410fd050 x4 : 0000000000200000 x3 : 0000000000000000 [ 1457.286386] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff00008590f000 [ 1457.293510] Call trace: [ 1457.295946] genpd_runtime_suspend+0x20/0x290 [ 1457.300296] __rpm_callback+0x48/0x1d8 [ 1457.304038] rpm_callback+0x6c/0x78 [ 1457.307515] rpm_suspend+0x10c/0x570 [ 1457.311077] pm_runtime_work+0xc4/0xc8 [ 1457.314813] process_one_work+0x138/0x248 [ 1457.318816] worker_thread+0x320/0x438 [ 1457.322552] kthread+0x110/0x114 [ 1457.325767] ret_from_fork+0x10/0x20

In the Linux kernel, the following vulnerability has been resolved: drm: xlnx: zynqmp_disp: layer may be null while releasing layer->info can be null if we have an error on the first layer in zynqmp_disp_create_layers

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Cancel RTC work during ufshcd_remove() Currently, RTC work is only cancelled during __ufshcd_wl_suspend(). When ufshcd is removed in ufshcd_remove(), RTC work is not cancelled. Due to this, any further trigger of the RTC work after ufshcd_remove() would result in a NULL pointer dereference as below: Unable to handle kernel NULL pointer dereference at virtual address 00000000000002a4 Workqueue: events ufshcd_rtc_work Call trace: _raw_spin_lock_irqsave+0x34/0x8c pm_runtime_get_if_active+0x24/0xb4 ufshcd_rtc_work+0x124/0x19c process_scheduled_works+0x18c/0x2d8 worker_thread+0x144/0x280 kthread+0x11c/0x128 ret_from_fork+0x10/0x20 Since RTC work accesses the ufshcd internal structures, it should be cancelled when ufshcd is removed. So do that in ufshcd_remove(), as per the order in ufshcd_init().

In the Linux kernel, the following vulnerability has been resolved: IB/mlx5: Fix UMR pd cleanup on error flow of driver init The cited commit moves the pd allocation from function mlx5r_umr_resource_cleanup() to a new function mlx5r_umr_cleanup(). So the fix in commit [1] is broken. In error flow, will hit panic [2]. Fix it by checking pd pointer to avoid panic if it is NULL; [1] RDMA/mlx5: Fix UMR cleanup on error flow of driver init [2] [ 347.567063] infiniband mlx5_0: Couldn't register device with driver model [ 347.591382] BUG: kernel NULL pointer dereference, address: 0000000000000020 [ 347.593438] #PF: supervisor read access in kernel mode [ 347.595176] #PF: error_code(0x0000) - not-present page [ 347.596962] PGD 0 P4D 0 [ 347.601361] RIP: 0010:ib_dealloc_pd_user+0x12/0xc0 [ib_core] [ 347.604171] RSP: 0018:ffff888106293b10 EFLAGS: 00010282 [ 347.604834] RAX: 0000000000000000 RBX: 000000000000000e RCX: 0000000000000000 [ 347.605672] RDX: ffff888106293ad0 RSI: 0000000000000000 RDI: 0000000000000000 [ 347.606529] RBP: 0000000000000000 R08: ffff888106293ae0 R09: ffff888106293ae0 [ 347.607379] R10: 0000000000000a06 R11: 0000000000000000 R12: 0000000000000000 [ 347.608224] R13: ffffffffa0704dc0 R14: 0000000000000001 R15: 0000000000000001 [ 347.609067] FS: 00007fdc720cd9c0(0000) GS:ffff88852c880000(0000) knlGS:0000000000000000 [ 347.610094] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 347.610727] CR2: 0000000000000020 CR3: 0000000103012003 CR4: 0000000000370eb0 [ 347.611421] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 347.612113] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 347.612804] Call Trace: [ 347.613130] <TASK> [ 347.613417] ? __die+0x20/0x60 [ 347.613793] ? page_fault_oops+0x150/0x3e0 [ 347.614243] ? free_msg+0x68/0x80 [mlx5_core] [ 347.614840] ? cmd_exec+0x48f/0x11d0 [mlx5_core] [ 347.615359] ? exc_page_fault+0x74/0x130 [ 347.615808] ? asm_exc_page_fault+0x22/0x30 [ 347.616273] ? ib_dealloc_pd_user+0x12/0xc0 [ib_core] [ 347.616801] mlx5r_umr_cleanup+0x23/0x90 [mlx5_ib] [ 347.617365] mlx5_ib_stage_pre_ib_reg_umr_cleanup+0x36/0x40 [mlx5_ib] [ 347.618025] __mlx5_ib_add+0x96/0xd0 [mlx5_ib] [ 347.618539] mlx5r_probe+0xe9/0x310 [mlx5_ib] [ 347.619032] ? kernfs_add_one+0x107/0x150 [ 347.619478] ? __mlx5_ib_add+0xd0/0xd0 [mlx5_ib] [ 347.619984] auxiliary_bus_probe+0x3e/0x90 [ 347.620448] really_probe+0xc5/0x3a0 [ 347.620857] __driver_probe_device+0x80/0x160 [ 347.621325] driver_probe_device+0x1e/0x90 [ 347.621770] __driver_attach+0xec/0x1c0 [ 347.622213] ? __device_attach_driver+0x100/0x100 [ 347.622724] bus_for_each_dev+0x71/0xc0 [ 347.623151] bus_add_driver+0xed/0x240 [ 347.623570] driver_register+0x58/0x100 [ 347.623998] __auxiliary_driver_register+0x6a/0xc0 [ 347.624499] ? driver_register+0xae/0x100 [ 347.624940] ? 0xffffffffa0893000 [ 347.625329] mlx5_ib_init+0x16a/0x1e0 [mlx5_ib] [ 347.625845] do_one_initcall+0x4a/0x2a0 [ 347.626273] ? gcov_event+0x2e2/0x3a0 [ 347.626706] do_init_module+0x8a/0x260 [ 347.627126] init_module_from_file+0x8b/0xd0 [ 347.627596] __x64_sys_finit_module+0x1ca/0x2f0 [ 347.628089] do_syscall_64+0x4c/0x100

In the Linux kernel, the following vulnerability has been resolved: ima: Avoid blocking in RCU read-side critical section A panic happens in ima_match_policy: BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 PGD 42f873067 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 5 PID: 1286325 Comm: kubeletmonit.sh Kdump: loaded Tainted: P Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 RIP: 0010:ima_match_policy+0x84/0x450 Code: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39 7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea 44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f RSP: 0018:ff71570009e07a80 EFLAGS: 00010207 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200 RDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739 R10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970 R13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001 FS: 00007f5195b51740(0000) GS:ff3e278b12d40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ima_get_action+0x22/0x30 process_measurement+0xb0/0x830 ? page_add_file_rmap+0x15/0x170 ? alloc_set_pte+0x269/0x4c0 ? prep_new_page+0x81/0x140 ? simple_xattr_get+0x75/0xa0 ? selinux_file_open+0x9d/0xf0 ima_file_check+0x64/0x90 path_openat+0x571/0x1720 do_filp_open+0x9b/0x110 ? page_counter_try_charge+0x57/0xc0 ? files_cgroup_alloc_fd+0x38/0x60 ? __alloc_fd+0xd4/0x250 ? do_sys_open+0x1bd/0x250 do_sys_open+0x1bd/0x250 do_syscall_64+0x5d/0x1d0 entry_SYSCALL_64_after_hwframe+0x65/0xca Commit c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") introduced call to ima_lsm_copy_rule within a RCU read-side critical section which contains kmalloc with GFP_KERNEL. This implies a possible sleep and violates limitations of RCU read-side critical sections on non-PREEMPT systems. Sleeping within RCU read-side critical section might cause synchronize_rcu() returning early and break RCU protection, allowing a UAF to happen. The root cause of this issue could be described as follows: | Thread A | Thread B | | |ima_match_policy | | | rcu_read_lock | |ima_lsm_update_rule | | | synchronize_rcu | | | | kmalloc(GFP_KERNEL)| | | sleep | ==> synchronize_rcu returns early | kfree(entry) | | | | entry = entry->next| ==> UAF happens and entry now becomes NULL (or could be anything). | | entry->action | ==> Accessing entry might cause panic. To fix this issue, we are converting all kmalloc that is called within RCU read-side critical section to use GFP_ATOMIC. [PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case]

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Fix a possible null pointer dereference In function lpfc_xcvr_data_show, the memory allocation with kmalloc might fail, thereby making rdp_context a null pointer. In the following context and functions that use this pointer, there are dereferencing operations, leading to null pointer dereference. To fix this issue, a null pointer check should be added. If it is null, use scnprintf to notify the user and return len.

In the Linux kernel, the following vulnerability has been resolved: ASoC: amd: Adjust error handling in case of absent codec device acpi_get_first_physical_node() can return NULL in several cases (no such device, ACPI table error, reference count drop to 0, etc). Existing check just emit error message, but doesn't perform return. Then this NULL pointer is passed to devm_acpi_dev_add_driver_gpios() where it is dereferenced. Adjust this error handling by adding error code return. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: fix NULL pointer dereference during unbind race Commit b81ac4395bbe ("usb: gadget: uvc: allow for application to cleanly shutdown") introduced two stages of synchronization waits totaling 1500ms in uvc_function_unbind() to prevent several types of kernel panics. However, this timing-based approach is insufficient during power management (PM) transitions. When the PM subsystem starts freezing user space processes, the wait_event_interruptible_timeout() is aborted early, which allows the unbind thread to proceed and nullify the gadget pointer (cdev->gadget = NULL): [ 814.123447][ T947] configfs-gadget.g1 gadget.0: uvc: uvc_function_unbind() [ 814.178583][ T3173] PM: suspend entry (deep) [ 814.192487][ T3173] Freezing user space processes [ 814.197668][ T947] configfs-gadget.g1 gadget.0: uvc: uvc_function_unbind no clean disconnect, wait for release When the PM subsystem resumes or aborts the suspend and tasks are restarted, the V4L2 release path is executed and attempts to access the already nullified gadget pointer, triggering a kernel panic: [ 814.292597][ C0] PM: pm_system_irq_wakeup: 479 triggered dhdpcie_host_wake [ 814.386727][ T3173] Restarting tasks ... [ 814.403522][ T4558] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000030 [ 814.404021][ T4558] pc : usb_gadget_deactivate+0x14/0xf4 [ 814.404031][ T4558] lr : usb_function_deactivate+0x54/0x94 [ 814.404078][ T4558] Call trace: [ 814.404080][ T4558] usb_gadget_deactivate+0x14/0xf4 [ 814.404083][ T4558] usb_function_deactivate+0x54/0x94 [ 814.404087][ T4558] uvc_function_disconnect+0x1c/0x5c [ 814.404092][ T4558] uvc_v4l2_release+0x44/0xac [ 814.404095][ T4558] v4l2_release+0xcc/0x130 Address the race condition and NULL pointer dereference by: 1. State Synchronization (flag + mutex) Introduce a 'func_unbound' flag in struct uvc_device. This allows uvc_function_disconnect() to safely skip accessing the nullified cdev->gadget pointer. As suggested by Alan Stern, this flag is protected by a new mutex (uvc->lock) to ensure proper memory ordering and prevent instruction reordering or speculative loads. This mutex is also used to protect 'func_connected' for consistent state management. 2. Explicit Synchronization (completion) Use a completion to synchronize uvc_function_unbind() with the uvc_vdev_release() callback. This prevents Use-After-Free (UAF) by ensuring struct uvc_device is freed after all video device resources are released.

net/nfc/llcp_sock.c in the Linux kernel before 5.12.10 allows local unprivileged users to cause a denial of service (NULL pointer dereference and BUG) by making a getsockname call after a certain type of failure of a bind call.

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: drm/xe: Check pat.ops before dumping PAT settings We may leave pat.ops unset when running on brand new platform or when running as a VF. While the former is unlikely, the latter is valid (future) use case and will cause NPD when someone will try to dump PAT settings by debugfs. It's better to check pointer to pat.ops instead of specific .dump hook, as we have this hook always defined for every .ops variant.

In the Linux kernel, the following vulnerability has been resolved: ata: libata-core: Fix null pointer dereference on error If the ata_port_alloc() call in ata_host_alloc() fails, ata_host_release() will get called. However, the code in ata_host_release() tries to free ata_port struct members unconditionally, which can lead to the following: BUG: unable to handle page fault for address: 0000000000003990 PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 10 PID: 594 Comm: (udev-worker) Not tainted 6.10.0-rc5 #44 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:ata_host_release.cold+0x2f/0x6e [libata] Code: e4 4d 63 f4 44 89 e2 48 c7 c6 90 ad 32 c0 48 c7 c7 d0 70 33 c0 49 83 c6 0e 41 RSP: 0018:ffffc90000ebb968 EFLAGS: 00010246 RAX: 0000000000000041 RBX: ffff88810fb52e78 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88813b3218c0 RDI: ffff88813b3218c0 RBP: ffff88810fb52e40 R08: 0000000000000000 R09: 6c65725f74736f68 R10: ffffc90000ebb738 R11: 73692033203a746e R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000011 R15: 0000000000000006 FS: 00007f6cc55b9980(0000) GS:ffff88813b300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000003990 CR3: 00000001122a2000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> ? __die_body.cold+0x19/0x27 ? page_fault_oops+0x15a/0x2f0 ? exc_page_fault+0x7e/0x180 ? asm_exc_page_fault+0x26/0x30 ? ata_host_release.cold+0x2f/0x6e [libata] ? ata_host_release.cold+0x2f/0x6e [libata] release_nodes+0x35/0xb0 devres_release_group+0x113/0x140 ata_host_alloc+0xed/0x120 [libata] ata_host_alloc_pinfo+0x14/0xa0 [libata] ahci_init_one+0x6c9/0xd20 [ahci] Do not access ata_port struct members unconditionally.

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: During vport delete send async logout explicitly During vport delete, it is observed that during unload we hit a crash because of stale entries in outstanding command array. For all these stale I/O entries, eh_abort was issued and aborted (fast_fail_io = 2009h) but I/Os could not complete while vport delete is in process of deleting. BUG: kernel NULL pointer dereference, address: 000000000000001c #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI Workqueue: qla2xxx_wq qla_do_work [qla2xxx] RIP: 0010:dma_direct_unmap_sg+0x51/0x1e0 RSP: 0018:ffffa1e1e150fc68 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000021 RCX: 0000000000000001 RDX: 0000000000000021 RSI: 0000000000000000 RDI: ffff8ce208a7a0d0 RBP: ffff8ce208a7a0d0 R08: 0000000000000000 R09: ffff8ce378aac9c8 R10: ffff8ce378aac8a0 R11: ffffa1e1e150f9d8 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8ce378aac9c8 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8d217f000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000001c CR3: 0000002089acc000 CR4: 0000000000350ee0 Call Trace: <TASK> qla2xxx_qpair_sp_free_dma+0x417/0x4e0 ? qla2xxx_qpair_sp_compl+0x10d/0x1a0 ? qla2x00_status_entry+0x768/0x2830 ? newidle_balance+0x2f0/0x430 ? dequeue_entity+0x100/0x3c0 ? qla24xx_process_response_queue+0x6a1/0x19e0 ? __schedule+0x2d5/0x1140 ? qla_do_work+0x47/0x60 ? process_one_work+0x267/0x440 ? process_one_work+0x440/0x440 ? worker_thread+0x2d/0x3d0 ? process_one_work+0x440/0x440 ? kthread+0x156/0x180 ? set_kthread_struct+0x50/0x50 ? ret_from_fork+0x22/0x30 </TASK> Send out async logout explicitly for all the ports during vport delete.

In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: avoid null_ptr_deref in vmw_framebuffer_surface_create_handle The 'vmw_user_object_buffer' function may return NULL with incorrect inputs. To avoid possible null pointer dereference, add a check whether the 'bo' is NULL in the vmw_framebuffer_surface_create_handle.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix NULL ptr deref in crypto_aead_setkey() Neither SMB3.0 or SMB3.02 supports encryption negotiate context, so when SMB2_GLOBAL_CAP_ENCRYPTION flag is set in the negotiate response, the client uses AES-128-CCM as the default cipher. See MS-SMB2 3.3.5.4. Commit b0abcd65ec54 ("smb: client: fix UAF in async decryption") added a @server->cipher_type check to conditionally call smb3_crypto_aead_allocate(), but that check would always be false as @server->cipher_type is unset for SMB3.02. Fix the following KASAN splat by setting @server->cipher_type for SMB3.02 as well. mount.cifs //srv/share /mnt -o vers=3.02,seal,... BUG: KASAN: null-ptr-deref in crypto_aead_setkey+0x2c/0x130 Read of size 8 at addr 0000000000000020 by task mount.cifs/1095 CPU: 1 UID: 0 PID: 1095 Comm: mount.cifs Not tainted 6.12.0 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x80 ? crypto_aead_setkey+0x2c/0x130 kasan_report+0xda/0x110 ? crypto_aead_setkey+0x2c/0x130 crypto_aead_setkey+0x2c/0x130 crypt_message+0x258/0xec0 [cifs] ? __asan_memset+0x23/0x50 ? __pfx_crypt_message+0x10/0x10 [cifs] ? mark_lock+0xb0/0x6a0 ? hlock_class+0x32/0xb0 ? mark_lock+0xb0/0x6a0 smb3_init_transform_rq+0x352/0x3f0 [cifs] ? lock_acquire.part.0+0xf4/0x2a0 smb_send_rqst+0x144/0x230 [cifs] ? __pfx_smb_send_rqst+0x10/0x10 [cifs] ? hlock_class+0x32/0xb0 ? smb2_setup_request+0x225/0x3a0 [cifs] ? __pfx_cifs_compound_last_callback+0x10/0x10 [cifs] compound_send_recv+0x59b/0x1140 [cifs] ? __pfx_compound_send_recv+0x10/0x10 [cifs] ? __create_object+0x5e/0x90 ? hlock_class+0x32/0xb0 ? do_raw_spin_unlock+0x9a/0xf0 cifs_send_recv+0x23/0x30 [cifs] SMB2_tcon+0x3ec/0xb30 [cifs] ? __pfx_SMB2_tcon+0x10/0x10 [cifs] ? lock_acquire.part.0+0xf4/0x2a0 ? __pfx_lock_release+0x10/0x10 ? do_raw_spin_trylock+0xc6/0x120 ? lock_acquire+0x3f/0x90 ? _get_xid+0x16/0xd0 [cifs] ? __pfx_SMB2_tcon+0x10/0x10 [cifs] ? cifs_get_smb_ses+0xcdd/0x10a0 [cifs] cifs_get_smb_ses+0xcdd/0x10a0 [cifs] ? __pfx_cifs_get_smb_ses+0x10/0x10 [cifs] ? cifs_get_tcp_session+0xaa0/0xca0 [cifs] cifs_mount_get_session+0x8a/0x210 [cifs] dfs_mount_share+0x1b0/0x11d0 [cifs] ? __pfx___lock_acquire+0x10/0x10 ? __pfx_dfs_mount_share+0x10/0x10 [cifs] ? lock_acquire.part.0+0xf4/0x2a0 ? find_held_lock+0x8a/0xa0 ? hlock_class+0x32/0xb0 ? lock_release+0x203/0x5d0 cifs_mount+0xb3/0x3d0 [cifs] ? do_raw_spin_trylock+0xc6/0x120 ? __pfx_cifs_mount+0x10/0x10 [cifs] ? lock_acquire+0x3f/0x90 ? find_nls+0x16/0xa0 ? smb3_update_mnt_flags+0x372/0x3b0 [cifs] cifs_smb3_do_mount+0x1e2/0xc80 [cifs] ? __pfx_vfs_parse_fs_string+0x10/0x10 ? __pfx_cifs_smb3_do_mount+0x10/0x10 [cifs] smb3_get_tree+0x1bf/0x330 [cifs] vfs_get_tree+0x4a/0x160 path_mount+0x3c1/0xfb0 ? kasan_quarantine_put+0xc7/0x1d0 ? __pfx_path_mount+0x10/0x10 ? kmem_cache_free+0x118/0x3e0 ? user_path_at+0x74/0xa0 __x64_sys_mount+0x1a6/0x1e0 ? __pfx___x64_sys_mount+0x10/0x10 ? mark_held_locks+0x1a/0x90 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Move events notifier registration to be after device registration Move pkey change work initialization and cleanup from device resources stage to notifier stage, since this is the stage which handles this work events. Fix a race between the device deregistration and pkey change work by moving MLX5_IB_STAGE_DEVICE_NOTIFIER to be after MLX5_IB_STAGE_IB_REG in order to ensure that the notifier is deregistered before the device during cleanup. Which ensures there are no works that are being executed after the device has already unregistered which can cause the panic below. BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 630071 Comm: kworker/1:2 Kdump: loaded Tainted: G W OE --------- --- 5.14.0-162.6.1.el9_1.x86_64 #1 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090008 02/27/2023 Workqueue: events pkey_change_handler [mlx5_ib] RIP: 0010:setup_qp+0x38/0x1f0 [mlx5_ib] Code: ee 41 54 45 31 e4 55 89 f5 53 48 89 fb 48 83 ec 20 8b 77 08 65 48 8b 04 25 28 00 00 00 48 89 44 24 18 48 8b 07 48 8d 4c 24 16 <4c> 8b 38 49 8b 87 80 0b 00 00 4c 89 ff 48 8b 80 08 05 00 00 8b 40 RSP: 0018:ffffbcc54068be20 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff954054494128 RCX: ffffbcc54068be36 RDX: ffff954004934000 RSI: 0000000000000001 RDI: ffff954054494128 RBP: 0000000000000023 R08: ffff954001be2c20 R09: 0000000000000001 R10: ffff954001be2c20 R11: ffff9540260133c0 R12: 0000000000000000 R13: 0000000000000023 R14: 0000000000000000 R15: ffff9540ffcb0905 FS: 0000000000000000(0000) GS:ffff9540ffc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000010625c001 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mlx5_ib_gsi_pkey_change+0x20/0x40 [mlx5_ib] process_one_work+0x1e8/0x3c0 worker_thread+0x50/0x3b0 ? rescuer_thread+0x380/0x380 kthread+0x149/0x170 ? set_kthread_struct+0x50/0x50 ret_from_fork+0x22/0x30 Modules linked in: rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) ib_umad(OE) mlx5_ib(OE) mlx5_fwctl(OE) fwctl(OE) ib_uverbs(OE) mlx5_core(OE) mlxdevm(OE) ib_core(OE) mlx_compat(OE) psample mlxfw(OE) tls knem(OE) netconsole nfsv3 nfs_acl nfs lockd grace fscache netfs qrtr rfkill sunrpc intel_rapl_msr intel_rapl_common rapl hv_balloon hv_utils i2c_piix4 pcspkr joydev fuse ext4 mbcache jbd2 sr_mod sd_mod cdrom t10_pi sg ata_generic pci_hyperv pci_hyperv_intf hyperv_drm drm_shmem_helper drm_kms_helper hv_storvsc syscopyarea hv_netvsc sysfillrect sysimgblt hid_hyperv fb_sys_fops scsi_transport_fc hyperv_keyboard drm ata_piix crct10dif_pclmul crc32_pclmul crc32c_intel libata ghash_clmulni_intel hv_vmbus serio_raw [last unloaded: ib_core] CR2: 0000000000000000 ---[ end trace f6f8be4eae12f7bc ]---

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix null check for pipe_ctx->plane_state in dcn20_program_pipe This commit addresses a null pointer dereference issue in dcn20_program_pipe(). Previously, commit 8e4ed3cf1642 ("drm/amd/display: Add null check for pipe_ctx->plane_state in dcn20_program_pipe") partially fixed the null pointer dereference issue. However, in dcn20_update_dchubp_dpp(), the variable pipe_ctx is passed in, and plane_state is accessed again through pipe_ctx. Multiple if statements directly call attributes of plane_state, leading to potential null pointer dereference issues. This patch adds necessary null checks to ensure stability.

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix null-ptr-deref in f2fs_submit_page_bio() There's issue as follows when concurrently installing the f2fs.ko module and mounting the f2fs file system: KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] RIP: 0010:__bio_alloc+0x2fb/0x6c0 [f2fs] Call Trace: <TASK> f2fs_submit_page_bio+0x126/0x8b0 [f2fs] __get_meta_page+0x1d4/0x920 [f2fs] get_checkpoint_version.constprop.0+0x2b/0x3c0 [f2fs] validate_checkpoint+0xac/0x290 [f2fs] f2fs_get_valid_checkpoint+0x207/0x950 [f2fs] f2fs_fill_super+0x1007/0x39b0 [f2fs] mount_bdev+0x183/0x250 legacy_get_tree+0xf4/0x1e0 vfs_get_tree+0x88/0x340 do_new_mount+0x283/0x5e0 path_mount+0x2b2/0x15b0 __x64_sys_mount+0x1fe/0x270 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e Above issue happens as the biset of the f2fs file system is not initialized before register "f2fs_fs_type". To address above issue just register "f2fs_fs_type" at the last in init_f2fs_fs(). Ensure that all f2fs file system resources are initialized.

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

In the Linux kernel, the following vulnerability has been resolved: ASoC: imx-audmix: Add NULL check in imx_audmix_probe devm_kasprintf() can return a NULL pointer on failure,but this returned value in imx_audmix_probe() is not checked. Add NULL check in imx_audmix_probe(), to handle kernel NULL pointer dereference error.

In the Linux kernel, the following vulnerability has been resolved: nfs/blocklayout: Don't attempt unregister for invalid block device Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key unregistration") an unmount of a pNFS SCSI layout-enabled NFS may dereference a NULL block_device in: bl_unregister_scsi+0x16/0xe0 [blocklayoutdriver] bl_free_device+0x70/0x80 [blocklayoutdriver] bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver] nfs4_put_deviceid_node+0x60/0xc0 [nfsv4] nfs4_deviceid_purge_client+0x132/0x190 [nfsv4] unset_pnfs_layoutdriver+0x59/0x60 [nfsv4] nfs4_destroy_server+0x36/0x70 [nfsv4] nfs_free_server+0x23/0xe0 [nfs] deactivate_locked_super+0x30/0xb0 cleanup_mnt+0xba/0x150 task_work_run+0x59/0x90 syscall_exit_to_user_mode+0x217/0x220 do_syscall_64+0x8e/0x160 This happens because even though we were able to create the nfs4_deviceid_node, the lookup for the device was unable to attach the block device to the pnfs_block_dev. If we never found a block device to register, we can avoid this case with the PNFS_BDEV_REGISTERED flag. Move the deref behind the test for the flag.

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix null-ptr-deref in block_dirty_buffer tracepoint When using the "block:block_dirty_buffer" tracepoint, mark_buffer_dirty() may cause a NULL pointer dereference, or a general protection fault when KASAN is enabled. This happens because, since the tracepoint was added in mark_buffer_dirty(), it references the dev_t member bh->b_bdev->bd_dev regardless of whether the buffer head has a pointer to a block_device structure. In the current implementation, nilfs_grab_buffer(), which grabs a buffer to read (or create) a block of metadata, including b-tree node blocks, does not set the block device, but instead does so only if the buffer is not in the "uptodate" state for each of its caller block reading functions. However, if the uptodate flag is set on a folio/page, and the buffer heads are detached from it by try_to_free_buffers(), and new buffer heads are then attached by create_empty_buffers(), the uptodate flag may be restored to each buffer without the block device being set to bh->b_bdev, and mark_buffer_dirty() may be called later in that state, resulting in the bug mentioned above. Fix this issue by making nilfs_grab_buffer() always set the block device of the super block structure to the buffer head, regardless of the state of the buffer's uptodate flag.

An issue was discovered in drivers/media/test-drivers/vidtv/vidtv_bridge.c in the Linux kernel 6.2. There is a NULL pointer dereference in vidtv_mux_stop_thread. In vidtv_stop_streaming, after dvb->mux=NULL occurs, it executes vidtv_mux_stop_thread(dvb->mux).

In the Linux kernel, the following vulnerability has been resolved: ext4: don't allow journal inode to have encrypt flag Mounting a filesystem whose journal inode has the encrypt flag causes a NULL dereference in fscrypt_limit_io_blocks() when the 'inlinecrypt' mount option is used. The problem is that when jbd2_journal_init_inode() calls bmap(), it eventually finds its way into ext4_iomap_begin(), which calls fscrypt_limit_io_blocks(). fscrypt_limit_io_blocks() requires that if the inode is encrypted, then its encryption key must already be set up. That's not the case here, since the journal inode is never "opened" like a normal file would be. Hence the crash. A reproducer is: mkfs.ext4 -F /dev/vdb debugfs -w /dev/vdb -R "set_inode_field <8> flags 0x80808" mount /dev/vdb /mnt -o inlinecrypt To fix this, make ext4 consider journal inodes with the encrypt flag to be invalid. (Note, maybe other flags should be rejected on the journal inode too. For now, this is just the minimal fix for the above issue.) I've marked this as fixing the commit that introduced the call to fscrypt_limit_io_blocks(), since that's what made an actual crash start being possible. But this fix could be applied to any version of ext4 that supports the encrypt feature.

In the Linux kernel, the following vulnerability has been resolved: firmware: qcom: scm: fix a NULL-pointer dereference Some SCM calls can be invoked with __scm being NULL (the driver may not have been and will not be probed as there's no SCM entry in device-tree). Make sure we don't dereference a NULL pointer.

In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix crash when unbinding If there is an error during some initialization related to firmware, the function ath12k_dp_cc_cleanup is called to release resources. However this is released again when the device is unbinded (ath12k_pci), and we get: BUG: kernel NULL pointer dereference, address: 0000000000000020 at RIP: 0010:ath12k_dp_cc_cleanup.part.0+0xb6/0x500 [ath12k] Call Trace: ath12k_dp_cc_cleanup ath12k_dp_free ath12k_core_deinit ath12k_pci_remove ... The issue is always reproducible from a VM because the MSI addressing initialization is failing. In order to fix the issue, just set to NULL the released structure in ath12k_dp_cc_cleanup at the end.

In the Linux kernel, the following vulnerability has been resolved: ASoC: mediatek: Assign dummy when codec not specified for a DAI link MediaTek sound card drivers are checking whether a DAI link is present and used on a board to assign the correct parameters and this is done by checking the codec DAI names at probe time. If no real codec is present, assign the dummy codec to the DAI link to avoid NULL pointer during string comparison.

In the Linux kernel, the following vulnerability has been resolved: phy: realtek: usb: fix NULL deref in rtk_usb3phy_probe In rtk_usb3phy_probe() devm_kzalloc() may return NULL but this returned value is not checked.

In the Linux kernel, the following vulnerability has been resolved: zram: fix NULL pointer in comp_algorithm_show() LTP reported a NULL pointer dereference as followed: CPU: 7 UID: 0 PID: 5995 Comm: cat Kdump: loaded Not tainted 6.12.0-rc6+ #3 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __pi_strcmp+0x24/0x140 lr : zcomp_available_show+0x60/0x100 [zram] sp : ffff800088b93b90 x29: ffff800088b93b90 x28: 0000000000000001 x27: 0000000000400cc0 x26: 0000000000000ffe x25: ffff80007b3e2388 x24: 0000000000000000 x23: ffff80007b3e2390 x22: ffff0004041a9000 x21: ffff80007b3e2900 x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: ffff80007b3e2900 x9 : ffff80007b3cb280 x8 : 0101010101010101 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000040 x4 : 0000000000000000 x3 : 00656c722d6f7a6c x2 : 0000000000000000 x1 : ffff80007b3e2900 x0 : 0000000000000000 Call trace: __pi_strcmp+0x24/0x140 comp_algorithm_show+0x40/0x70 [zram] dev_attr_show+0x28/0x80 sysfs_kf_seq_show+0x90/0x140 kernfs_seq_show+0x34/0x48 seq_read_iter+0x1d4/0x4e8 kernfs_fop_read_iter+0x40/0x58 new_sync_read+0x9c/0x168 vfs_read+0x1a8/0x1f8 ksys_read+0x74/0x108 __arm64_sys_read+0x24/0x38 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x38/0x138 el0t_64_sync_handler+0xc0/0xc8 el0t_64_sync+0x188/0x190 The zram->comp_algs[ZRAM_PRIMARY_COMP] can be NULL in zram_add() if comp_algorithm_set() has not been called. User can access the zram device by sysfs after device_add_disk(), so there is a time window to trigger the NULL pointer dereference. Move it ahead device_add_disk() to make sure when user can access the zram device, it is ready. comp_algorithm_set() is protected by zram->init_lock in other places and no such problem.

In the AppleTalk subsystem in the Linux kernel before 5.1, there is a potential NULL pointer dereference because register_snap_client may return NULL. This will lead to denial of service in net/appletalk/aarp.c and net/appletalk/ddp.c, as demonstrated by unregister_snap_client, aka CID-9804501fa122.

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix null-ptr-deref in block_touch_buffer tracepoint Patch series "nilfs2: fix null-ptr-deref bugs on block tracepoints". This series fixes null pointer dereference bugs that occur when using nilfs2 and two block-related tracepoints. This patch (of 2): It has been reported that when using "block:block_touch_buffer" tracepoint, touch_buffer() called from __nilfs_get_folio_block() causes a NULL pointer dereference, or a general protection fault when KASAN is enabled. This happens because since the tracepoint was added in touch_buffer(), it references the dev_t member bh->b_bdev->bd_dev regardless of whether the buffer head has a pointer to a block_device structure. In the current implementation, the block_device structure is set after the function returns to the caller. Here, touch_buffer() is used to mark the folio/page that owns the buffer head as accessed, but the common search helper for folio/page used by the caller function was optimized to mark the folio/page as accessed when it was reimplemented a long time ago, eliminating the need to call touch_buffer() here in the first place. So this solves the issue by eliminating the touch_buffer() call itself.