A flaw was found in the Linux kernel's NVMe driver. This issue may allow an unauthenticated malicious actor to send a set of crafted TCP packages when using NVMe over TCP, leading the NVMe driver to a NULL pointer dereference in the NVMe driver, causing kernel panic and a denial of service.

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7921: fix kernel panic due to null pointer dereference Address a kernel panic caused by a null pointer dereference in the `mt792x_rx_get_wcid` function. The issue arises because the `deflink` structure is not properly initialized with the `sta` context. This patch ensures that the `deflink` structure is correctly linked to the `sta` context, preventing the null pointer dereference. BUG: kernel NULL pointer dereference, address: 0000000000000400 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 UID: 0 PID: 470 Comm: mt76-usb-rx phy Not tainted 6.12.13-gentoo-dist #1 Hardware name: /AMD HUDSON-M1, BIOS 4.6.4 11/15/2011 RIP: 0010:mt792x_rx_get_wcid+0x48/0x140 [mt792x_lib] RSP: 0018:ffffa147c055fd98 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff8e9ecb652000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8e9ecb652000 RBP: 0000000000000685 R08: ffff8e9ec6570000 R09: 0000000000000000 R10: ffff8e9ecd2ca000 R11: ffff8e9f22a217c0 R12: 0000000038010119 R13: 0000000080843801 R14: ffff8e9ec6570000 R15: ffff8e9ecb652000 FS: 0000000000000000(0000) GS:ffff8e9f22a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000400 CR3: 000000000d2ea000 CR4: 00000000000006f0 Call Trace: <TASK> ? __die_body.cold+0x19/0x27 ? page_fault_oops+0x15a/0x2f0 ? search_module_extables+0x19/0x60 ? search_bpf_extables+0x5f/0x80 ? exc_page_fault+0x7e/0x180 ? asm_exc_page_fault+0x26/0x30 ? mt792x_rx_get_wcid+0x48/0x140 [mt792x_lib] mt7921_queue_rx_skb+0x1c6/0xaa0 [mt7921_common] mt76u_alloc_queues+0x784/0x810 [mt76_usb] ? __pfx___mt76_worker_fn+0x10/0x10 [mt76] __mt76_worker_fn+0x4f/0x80 [mt76] kthread+0xd2/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x34/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: HID: appleir: Fix potential NULL dereference at raw event handle Syzkaller reports a NULL pointer dereference issue in input_event(). BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: null-ptr-deref in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: null-ptr-deref in is_event_supported drivers/input/input.c:67 [inline] BUG: KASAN: null-ptr-deref in input_event+0x42/0xa0 drivers/input/input.c:395 Read of size 8 at addr 0000000000000028 by task syz-executor199/2949 CPU: 0 UID: 0 PID: 2949 Comm: syz-executor199 Not tainted 6.13.0-rc4-syzkaller-00076-gf097a36ef88d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 kasan_report+0xd9/0x110 mm/kasan/report.c:602 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] is_event_supported drivers/input/input.c:67 [inline] input_event+0x42/0xa0 drivers/input/input.c:395 input_report_key include/linux/input.h:439 [inline] key_down drivers/hid/hid-appleir.c:159 [inline] appleir_raw_event+0x3e5/0x5e0 drivers/hid/hid-appleir.c:232 __hid_input_report.constprop.0+0x312/0x440 drivers/hid/hid-core.c:2111 hid_ctrl+0x49f/0x550 drivers/hid/usbhid/hid-core.c:484 __usb_hcd_giveback_urb+0x389/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x17f7/0x3960 drivers/usb/gadget/udc/dummy_hcd.c:1993 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1820 handle_softirqs+0x206/0x8d0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __mod_timer+0x8f6/0xdc0 kernel/time/timer.c:1185 add_timer+0x62/0x90 kernel/time/timer.c:1295 schedule_timeout+0x11f/0x280 kernel/time/sleep_timeout.c:98 usbhid_wait_io+0x1c7/0x380 drivers/hid/usbhid/hid-core.c:645 usbhid_init_reports+0x19f/0x390 drivers/hid/usbhid/hid-core.c:784 hiddev_ioctl+0x1133/0x15b0 drivers/hid/usbhid/hiddev.c:794 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 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 </TASK> This happens due to the malformed report items sent by the emulated device which results in a report, that has no fields, being added to the report list. Due to this appleir_input_configured() is never called, hidinput_connect() fails which results in the HID_CLAIMED_INPUT flag is not being set. However, it does not make appleir_probe() fail and lets the event callback to be called without the associated input device. Thus, add a check for the HID_CLAIMED_INPUT flag and leave the event hook early if the driver didn't claim any input_dev for some reason. Moreover, some other hid drivers accessing input_dev in their event callbacks do have similar checks, too. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

In the Linux kernel 4.15.0, a NULL pointer dereference was discovered in hfs_ext_read_extent in hfs.ko. This can occur during a mount of a crafted hfs filesystem.

In the Linux kernel, the following vulnerability has been resolved: usb: hub: Guard against accesses to uninitialized BOS descriptors Many functions in drivers/usb/core/hub.c and drivers/usb/core/hub.h access fields inside udev->bos without checking if it was allocated and initialized. If usb_get_bos_descriptor() fails for whatever reason, udev->bos will be NULL and those accesses will result in a crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 5 PID: 17818 Comm: kworker/5:1 Tainted: G W 5.15.108-18910-gab0e1cb584e1 #1 <HASH:1f9e 1> Hardware name: Google Kindred/Kindred, BIOS Google_Kindred.12672.413.0 02/03/2021 Workqueue: usb_hub_wq hub_event RIP: 0010:hub_port_reset+0x193/0x788 Code: 89 f7 e8 20 f7 15 00 48 8b 43 08 80 b8 96 03 00 00 03 75 36 0f b7 88 92 03 00 00 81 f9 10 03 00 00 72 27 48 8b 80 a8 03 00 00 <48> 83 78 18 00 74 19 48 89 df 48 8b 75 b0 ba 02 00 00 00 4c 89 e9 RSP: 0018:ffffab740c53fcf8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffa1bc5f678000 RCX: 0000000000000310 RDX: fffffffffffffdff RSI: 0000000000000286 RDI: ffffa1be9655b840 RBP: ffffab740c53fd70 R08: 00001b7d5edaa20c R09: ffffffffb005e060 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffffab740c53fd3e R14: 0000000000000032 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffffa1be96540000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 000000022e80c005 CR4: 00000000003706e0 Call Trace: hub_event+0x73f/0x156e ? hub_activate+0x5b7/0x68f process_one_work+0x1a2/0x487 worker_thread+0x11a/0x288 kthread+0x13a/0x152 ? process_one_work+0x487/0x487 ? kthread_associate_blkcg+0x70/0x70 ret_from_fork+0x1f/0x30 Fall back to a default behavior if the BOS descriptor isn't accessible and skip all the functionalities that depend on it: LPM support checks, Super Speed capabilitiy checks, U1/U2 states setup.

In the Linux kernel, the following vulnerability has been resolved: vfio/mdev: Fix a null-ptr-deref bug for mdev_unregister_parent() Inject fault while probing mdpy.ko, if kstrdup() of create_dir() fails in kobject_add_internal() in kobject_init_and_add() in mdev_type_add() in parent_create_sysfs_files(), it will return 0 and probe successfully. And when rmmod mdpy.ko, the mdpy_dev_exit() will call mdev_unregister_parent(), the mdev_type_remove() may traverse uninitialized parent->types[i] in parent_remove_sysfs_files(), and it will cause below null-ptr-deref. If mdev_type_add() fails, return the error code and kset_unregister() to fix the issue. general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 2 PID: 10215 Comm: rmmod Tainted: G W N 6.6.0-rc2+ #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Call Trace: <TASK> ? die_addr+0x3d/0xa0 ? exc_general_protection+0x144/0x220 ? asm_exc_general_protection+0x22/0x30 ? __kobject_del+0x62/0x1c0 kobject_del+0x32/0x50 parent_remove_sysfs_files+0xd6/0x170 [mdev] mdev_unregister_parent+0xfb/0x190 [mdev] ? mdev_register_parent+0x270/0x270 [mdev] ? find_module_all+0x9d/0xe0 mdpy_dev_exit+0x17/0x63 [mdpy] __do_sys_delete_module.constprop.0+0x2fa/0x4b0 ? module_flags+0x300/0x300 ? __fput+0x4e7/0xa00 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fbc813221b7 Code: 73 01 c3 48 8b 0d d1 8c 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 8c 2c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe780e0648 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00007ffe780e06a8 RCX: 00007fbc813221b7 RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055e214df9b58 RBP: 000055e214df9af0 R08: 00007ffe780df5c1 R09: 0000000000000000 R10: 00007fbc8139ecc0 R11: 0000000000000206 R12: 00007ffe780e0870 R13: 00007ffe780e0ed0 R14: 000055e214df9260 R15: 000055e214df9af0 </TASK> Modules linked in: mdpy(-) mdev vfio_iommu_type1 vfio [last unloaded: mdpy] Dumping ftrace buffer: (ftrace buffer empty) ---[ end trace 0000000000000000 ]--- RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: i915/perf: Fix NULL deref bugs with drm_dbg() calls When i915 perf interface is not available dereferencing it will lead to NULL dereferences. As returning -ENOTSUPP is pretty clear return when perf interface is not available. [tursulin: added stable tag] (cherry picked from commit 36f27350ff745bd228ab04d7845dfbffc177a889)

In the Linux kernel, the following vulnerability has been resolved: fs: Pass AT_GETATTR_NOSEC flag to getattr interface function When vfs_getattr_nosec() calls a filesystem's getattr interface function then the 'nosec' should propagate into this function so that vfs_getattr_nosec() can again be called from the filesystem's gettattr rather than vfs_getattr(). The latter would add unnecessary security checks that the initial vfs_getattr_nosec() call wanted to avoid. Therefore, introduce the getattr flag GETATTR_NOSEC and allow to pass with the new getattr_flags parameter to the getattr interface function. In overlayfs and ecryptfs use this flag to determine which one of the two functions to call. In a recent code change introduced to IMA vfs_getattr_nosec() ended up calling vfs_getattr() in overlayfs, which in turn called security_inode_getattr() on an exiting process that did not have current->fs set anymore, which then caused a kernel NULL pointer dereference. With this change the call to security_inode_getattr() can be avoided, thus avoiding the NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: sockmap, vsock: For connectible sockets allow only connected sockmap expects all vsocks to have a transport assigned, which is expressed in vsock_proto::psock_update_sk_prot(). However, there is an edge case where an unconnected (connectible) socket may lose its previously assigned transport. This is handled with a NULL check in the vsock/BPF recv path. Another design detail is that listening vsocks are not supposed to have any transport assigned at all. Which implies they are not supported by the sockmap. But this is complicated by the fact that a socket, before switching to TCP_LISTEN, may have had some transport assigned during a failed connect() attempt. Hence, we may end up with a listening vsock in a sockmap, which blows up quickly: KASAN: null-ptr-deref in range [0x0000000000000120-0x0000000000000127] CPU: 7 UID: 0 PID: 56 Comm: kworker/7:0 Not tainted 6.14.0-rc1+ Workqueue: vsock-loopback vsock_loopback_work RIP: 0010:vsock_read_skb+0x4b/0x90 Call Trace: sk_psock_verdict_data_ready+0xa4/0x2e0 virtio_transport_recv_pkt+0x1ca8/0x2acc vsock_loopback_work+0x27d/0x3f0 process_one_work+0x846/0x1420 worker_thread+0x5b3/0xf80 kthread+0x35a/0x700 ret_from_fork+0x2d/0x70 ret_from_fork_asm+0x1a/0x30 For connectible sockets, instead of relying solely on the state of vsk->transport, tell sockmap to only allow those representing established connections. This aligns with the behaviour for AF_INET and AF_UNIX.

In the Linux kernel, the following vulnerability has been resolved: apparmor: Fix null pointer deref when receiving skb during sock creation The panic below is observed when receiving ICMP packets with secmark set while an ICMP raw socket is being created. SK_CTX(sk)->label is updated in apparmor_socket_post_create(), but the packet is delivered to the socket before that, causing the null pointer dereference. Drop the packet if label context is not set. BUG: kernel NULL pointer dereference, address: 000000000000004c #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 407 Comm: a.out Not tainted 6.4.12-arch1-1 #1 3e6fa2753a2d75925c34ecb78e22e85a65d083df Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/28/2020 RIP: 0010:aa_label_next_confined+0xb/0x40 Code: 00 00 48 89 ef e8 d5 25 0c 00 e9 66 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 0f 1f 44 00 00 89 f0 <8b> 77 4c 39 c6 7e 1f 48 63 d0 48 8d 14 d7 eb 0b 83 c0 01 48 83 c2 RSP: 0018:ffffa92940003b08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000000e RDX: ffffa92940003be8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8b57471e7800 R08: ffff8b574c642400 R09: 0000000000000002 R10: ffffffffbd820eeb R11: ffffffffbeb7ff00 R12: ffff8b574c642400 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000 FS: 00007fb092ea7640(0000) GS:ffff8b577bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000004c CR3: 00000001020f2005 CR4: 00000000007706f0 PKRU: 55555554 Call Trace: <IRQ> ? __die+0x23/0x70 ? page_fault_oops+0x171/0x4e0 ? exc_page_fault+0x7f/0x180 ? asm_exc_page_fault+0x26/0x30 ? aa_label_next_confined+0xb/0x40 apparmor_secmark_check+0xec/0x330 security_sock_rcv_skb+0x35/0x50 sk_filter_trim_cap+0x47/0x250 sock_queue_rcv_skb_reason+0x20/0x60 raw_rcv+0x13c/0x210 raw_local_deliver+0x1f3/0x250 ip_protocol_deliver_rcu+0x4f/0x2f0 ip_local_deliver_finish+0x76/0xa0 __netif_receive_skb_one_core+0x89/0xa0 netif_receive_skb+0x119/0x170 ? __netdev_alloc_skb+0x3d/0x140 vmxnet3_rq_rx_complete+0xb23/0x1010 [vmxnet3 56a84f9c97178c57a43a24ec073b45a9d6f01f3a] vmxnet3_poll_rx_only+0x36/0xb0 [vmxnet3 56a84f9c97178c57a43a24ec073b45a9d6f01f3a] __napi_poll+0x28/0x1b0 net_rx_action+0x2a4/0x380 __do_softirq+0xd1/0x2c8 __irq_exit_rcu+0xbb/0xf0 common_interrupt+0x86/0xa0 </IRQ> <TASK> asm_common_interrupt+0x26/0x40 RIP: 0010:apparmor_socket_post_create+0xb/0x200 Code: 08 48 85 ff 75 a1 eb b1 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 54 <55> 48 89 fd 53 45 85 c0 0f 84 b2 00 00 00 48 8b 1d 80 56 3f 02 48 RSP: 0018:ffffa92940ce7e50 EFLAGS: 00000286 RAX: ffffffffbc756440 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000003 RSI: 0000000000000002 RDI: ffff8b574eaab740 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8b57444cec70 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000002 R14: ffff8b574eaab740 R15: ffffffffbd8e4748 ? __pfx_apparmor_socket_post_create+0x10/0x10 security_socket_post_create+0x4b/0x80 __sock_create+0x176/0x1f0 __sys_socket+0x89/0x100 __x64_sys_socket+0x17/0x20 do_syscall_64+0x5d/0x90 ? do_syscall_64+0x6c/0x90 ? do_syscall_64+0x6c/0x90 ? do_syscall_64+0x6c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc

In all android releases (Android for MSM, Firefox OS for MSM, QRD Android) from CAF using the linux kernel, asynchronous callbacks received a pointer to a callers local variable. Should the caller return early (e.g., timeout), the callback will dereference an invalid pointer.

In the Linux kernel, the following vulnerability has been resolved: tracing: Have trace_event_file have ref counters The following can crash the kernel: # cd /sys/kernel/tracing # echo 'p:sched schedule' > kprobe_events # exec 5>>events/kprobes/sched/enable # > kprobe_events # exec 5>&- The above commands: 1. Change directory to the tracefs directory 2. Create a kprobe event (doesn't matter what one) 3. Open bash file descriptor 5 on the enable file of the kprobe event 4. Delete the kprobe event (removes the files too) 5. Close the bash file descriptor 5 The above causes a crash! BUG: kernel NULL pointer dereference, address: 0000000000000028 #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: 6 PID: 877 Comm: bash Not tainted 6.5.0-rc4-test-00008-g2c6b6b1029d4-dirty #186 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:tracing_release_file_tr+0xc/0x50 What happens here is that the kprobe event creates a trace_event_file "file" descriptor that represents the file in tracefs to the event. It maintains state of the event (is it enabled for the given instance?). Opening the "enable" file gets a reference to the event "file" descriptor via the open file descriptor. When the kprobe event is deleted, the file is also deleted from the tracefs system which also frees the event "file" descriptor. But as the tracefs file is still opened by user space, it will not be totally removed until the final dput() is called on it. But this is not true with the event "file" descriptor that is already freed. If the user does a write to or simply closes the file descriptor it will reference the event "file" descriptor that was just freed, causing a use-after-free bug. To solve this, add a ref count to the event "file" descriptor as well as a new flag called "FREED". The "file" will not be freed until the last reference is released. But the FREE flag will be set when the event is removed to prevent any more modifications to that event from happening, even if there's still a reference to the event "file" descriptor.

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]

An issue was discovered on LG mobile devices with Android OS 8.0, 8.1, 9.0, and 10 software. System services may crash because of the lack of a NULL parameter check. The LG ID is LVE-SMP-200024 (November 2020).

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: cxl/mem: Fix shutdown order Ira reports that removing cxl_mock_mem causes a crash with the following trace: BUG: kernel NULL pointer dereference, address: 0000000000000044 [..] RIP: 0010:cxl_region_decode_reset+0x7f/0x180 [cxl_core] [..] Call Trace: <TASK> cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x29/0x40 [cxl_core] devres_release_all+0xb8/0x110 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1d2/0x210 bus_remove_device+0xd7/0x150 device_del+0x155/0x3e0 device_unregister+0x13/0x60 devm_release_action+0x4d/0x90 ? __pfx_unregister_port+0x10/0x10 [cxl_core] delete_endpoint+0x121/0x130 [cxl_core] devres_release_all+0xb8/0x110 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1d2/0x210 bus_remove_device+0xd7/0x150 device_del+0x155/0x3e0 ? lock_release+0x142/0x290 cdev_device_del+0x15/0x50 cxl_memdev_unregister+0x54/0x70 [cxl_core] This crash is due to the clearing out the cxl_memdev's driver context (@cxlds) before the subsystem is done with it. This is ultimately due to the region(s), that this memdev is a member, being torn down and expecting to be able to de-reference @cxlds, like here: static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) ... if (cxlds->rcd) goto endpoint_reset; ... Fix it by keeping the driver context valid until memdev-device unregistration, and subsequently the entire stack of related dependencies, unwinds.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix a NULL pointer dereference in amdgpu_dm_i2c_xfer() When ddc_service_construct() is called, it explicitly checks both the link type and whether there is something on the link which will dictate whether the pin is marked as hw_supported. If the pin isn't set or the link is not set (such as from unloading/reloading amdgpu in an IGT test) then fail the amdgpu_dm_i2c_xfer() call.

In the Linux kernel, the following vulnerability has been resolved: clk: mediatek: clk-mt2701: Add check for mtk_alloc_clk_data Add the check for the return value of mtk_alloc_clk_data() in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: serial: 8250_port: Check IRQ data before use In case the leaf driver wants to use IRQ polling (irq = 0) and IIR register shows that an interrupt happened in the 8250 hardware the IRQ data can be NULL. In such a case we need to skip the wake event as we came to this path from the timer interrupt and quite likely system is already awake. Without this fix we have got an Oops: serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A ... BUG: kernel NULL pointer dereference, address: 0000000000000010 RIP: 0010:serial8250_handle_irq+0x7c/0x240 Call Trace: ? serial8250_handle_irq+0x7c/0x240 ? __pfx_serial8250_timeout+0x10/0x10

In the Linux kernel, the following vulnerability has been resolved: nvme-fc: Prevent null pointer dereference in nvme_fc_io_getuuid() The nvme_fc_fcp_op structure describing an AEN operation is initialized with a null request structure pointer. An FC LLDD may make a call to nvme_fc_io_getuuid passing a pointer to an nvmefc_fcp_req for an AEN operation. Add validation of the request structure pointer before dereference.

In the Linux kernel, the following vulnerability has been resolved: gfs2: Fix kernel NULL pointer dereference in gfs2_rgrp_dump Syzkaller has reported a NULL pointer dereference when accessing rgd->rd_rgl in gfs2_rgrp_dump(). This can happen when creating rgd->rd_gl fails in read_rindex_entry(). Add a NULL pointer check in gfs2_rgrp_dump() to prevent that.

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: mux: Add check and kfree for kstrdup Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference. Moreover, use kfree() in the later error handling in order to avoid memory leak.

A vulnerability was found in Linux Kernel where in the spk_ttyio_receive_buf2() function, it would dereference spk_ttyio_synth without checking whether it is NULL or not, and may lead to a NULL-ptr deref crash.

In the Linux kernel, the following vulnerability has been resolved: scsi: ibmvfc: Remove BUG_ON in the case of an empty event pool In practice the driver should never send more commands than are allocated to a queue's event pool. In the unlikely event that this happens, the code asserts a BUG_ON, and in the case that the kernel is not configured to crash on panic returns a junk event pointer from the empty event list causing things to spiral from there. This BUG_ON is a historical artifact of the ibmvfc driver first being upstreamed, and it is well known now that the use of BUG_ON is bad practice except in the most unrecoverable scenario. There is nothing about this scenario that prevents the driver from recovering and carrying on. Remove the BUG_ON in question from ibmvfc_get_event() and return a NULL pointer in the case of an empty event pool. Update all call sites to ibmvfc_get_event() to check for a NULL pointer and perfrom the appropriate failure or recovery action.

In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: Fix a kernel panic when host sends an invalid H2C PDU length If the host sends an H2CData command with an invalid DATAL, the kernel may crash in nvmet_tcp_build_pdu_iovec(). Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 lr : nvmet_tcp_io_work+0x6ac/0x718 [nvmet_tcp] Call trace: process_one_work+0x174/0x3c8 worker_thread+0x2d0/0x3e8 kthread+0x104/0x110 Fix the bug by raising a fatal error if DATAL isn't coherent with the packet size. Also, the PDU length should never exceed the MAXH2CDATA parameter which has been communicated to the host in nvmet_tcp_handle_icreq().

In the Linux kernel, the following vulnerability has been resolved: powerpc/mm: Fix null-pointer dereference in pgtable_cache_add kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity.

In the Linux kernel, the following vulnerability has been resolved: net: wangxun: fix kernel panic due to null pointer When the device uses a custom subsystem vendor ID, the function wx_sw_init() returns before the memory of 'wx->mac_table' is allocated. The null pointer will causes the kernel panic.

Linux kernel before version 4.16-rc7 is vulnerable to a null pointer dereference in dccp_write_xmit() function in net/dccp/output.c in that allows a local user to cause a denial of service by a number of certain crafted system calls.

The ext4_xattr_check_entries function in fs/ext4/xattr.c in the Linux kernel through 4.15.15 does not properly validate xattr sizes, which causes misinterpretation of a size as an error code, and consequently allows attackers to cause a denial of service (get_acl NULL pointer dereference and system crash) via a crafted ext4 image.

An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. drivers/xen/events/events_base.c allows event-channel removal during the event-handling loop (a race condition). This can cause a use-after-free or NULL pointer dereference, as demonstrated by a dom0 crash via events for an in-reconfiguration paravirtualized device, aka CID-073d0552ead5.

In the Linux kernel, the following vulnerability has been resolved: scsi: libfc: Fix potential NULL pointer dereference in fc_lport_ptp_setup() fc_lport_ptp_setup() did not check the return value of fc_rport_create() which can return NULL and would cause a NULL pointer dereference. Address this issue by checking return value of fc_rport_create() and log error message on fc_rport_create() failed.

In the Linux kernel, the following vulnerability has been resolved: dmaengine: fix NULL pointer in channel unregistration function __dma_async_device_channel_register() can fail. In case of failure, chan->local is freed (with free_percpu()), and chan->local is nullified. When dma_async_device_unregister() is called (because of managed API or intentionally by DMA controller driver), channels are unconditionally unregistered, leading to this NULL pointer: [ 1.318693] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0 [...] [ 1.484499] Call trace: [ 1.486930] device_del+0x40/0x394 [ 1.490314] device_unregister+0x20/0x7c [ 1.494220] __dma_async_device_channel_unregister+0x68/0xc0 Look at dma_async_device_register() function error path, channel device unregistration is done only if chan->local is not NULL. Then add the same condition at the beginning of __dma_async_device_channel_unregister() function, to avoid NULL pointer issue whatever the API used to reach this function.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix possible NULL dereference in amdgpu_ras_query_error_status_helper() Return invalid error code -EINVAL for invalid block id. Fixes the below: drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:1183 amdgpu_ras_query_error_status_helper() error: we previously assumed 'info' could be null (see line 1176)

The ext4_iget function in fs/ext4/inode.c in the Linux kernel through 4.15.15 mishandles the case of a root directory with a zero i_links_count, which allows attackers to cause a denial of service (ext4_process_freed_data NULL pointer dereference and OOPS) via a crafted ext4 image.

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: clk: mediatek: clk-mt6779: Add check for mtk_alloc_clk_data Add the check for the return value of mtk_alloc_clk_data() in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: iio: adc: ad7091r: Allow users to configure device events AD7091R-5 devices are supported by the ad7091r-5 driver together with the ad7091r-base driver. Those drivers declared iio events for notifying user space when ADC readings fall bellow the thresholds of low limit registers or above the values set in high limit registers. However, to configure iio events and their thresholds, a set of callback functions must be implemented and those were not present until now. The consequence of trying to configure ad7091r-5 events without the proper callback functions was a null pointer dereference in the kernel because the pointers to the callback functions were not set. Implement event configuration callbacks allowing users to read/write event thresholds and enable/disable event generation. Since the event spec structs are generic to AD7091R devices, also move those from the ad7091r-5 driver the base driver so they can be reused when support for ad7091r-2/-4/-8 be added.

In the Linux kernel, the following vulnerability has been resolved: staging: gpib: Fix cb7210 pcmcia Oops The pcmcia_driver struct was still only using the old .name initialization in the drv field. This led to a NULL pointer deref Oops in strcmp called from pcmcia_register_driver. Initialize the pcmcia_driver struct name field.

In the Linux kernel, the following vulnerability has been resolved: net: fix NULL pointer in skb_segment_list Commit 3a1296a38d0c ("net: Support GRO/GSO fraglist chaining.") introduced UDP listifyed GRO. The segmentation relies on frag_list being untouched when passing through the network stack. This assumption can be broken sometimes, where frag_list itself gets pulled into linear area, leaving frag_list being NULL. When this happens it can trigger following NULL pointer dereference, and panic the kernel. Reverse the test condition should fix it. [19185.577801][ C1] BUG: kernel NULL pointer dereference, address: ... [19185.663775][ C1] RIP: 0010:skb_segment_list+0x1cc/0x390 ... [19185.834644][ C1] Call Trace: [19185.841730][ C1] <TASK> [19185.848563][ C1] __udp_gso_segment+0x33e/0x510 [19185.857370][ C1] inet_gso_segment+0x15b/0x3e0 [19185.866059][ C1] skb_mac_gso_segment+0x97/0x110 [19185.874939][ C1] __skb_gso_segment+0xb2/0x160 [19185.883646][ C1] udp_queue_rcv_skb+0xc3/0x1d0 [19185.892319][ C1] udp_unicast_rcv_skb+0x75/0x90 [19185.900979][ C1] ip_protocol_deliver_rcu+0xd2/0x200 [19185.910003][ C1] ip_local_deliver_finish+0x44/0x60 [19185.918757][ C1] __netif_receive_skb_one_core+0x8b/0xa0 [19185.927834][ C1] process_backlog+0x88/0x130 [19185.935840][ C1] __napi_poll+0x27/0x150 [19185.943447][ C1] net_rx_action+0x27e/0x5f0 [19185.951331][ C1] ? mlx5_cq_tasklet_cb+0x70/0x160 [mlx5_core] [19185.960848][ C1] __do_softirq+0xbc/0x25d [19185.968607][ C1] irq_exit_rcu+0x83/0xb0 [19185.976247][ C1] common_interrupt+0x43/0xa0 [19185.984235][ C1] asm_common_interrupt+0x22/0x40 ... [19186.094106][ C1] </TASK>

In the Linux kernel, the following vulnerability has been resolved: mtd: Fix gluebi NULL pointer dereference caused by ftl notifier If both ftl.ko and gluebi.ko are loaded, the notifier of ftl triggers NULL pointer dereference when trying to access ‘gluebi->desc’ in gluebi_read(). ubi_gluebi_init ubi_register_volume_notifier ubi_enumerate_volumes ubi_notify_all gluebi_notify nb->notifier_call() gluebi_create mtd_device_register mtd_device_parse_register add_mtd_device blktrans_notify_add not->add() ftl_add_mtd tr->add_mtd() scan_header mtd_read mtd_read_oob mtd_read_oob_std gluebi_read mtd->read() gluebi->desc - NULL Detailed reproduction information available at the Link [1], In the normal case, obtain gluebi->desc in the gluebi_get_device(), and access gluebi->desc in the gluebi_read(). However, gluebi_get_device() is not executed in advance in the ftl_add_mtd() process, which leads to NULL pointer dereference. The solution for the gluebi module is to run jffs2 on the UBI volume without considering working with ftl or mtdblock [2]. Therefore, this problem can be avoided by preventing gluebi from creating the mtdblock device after creating mtd partition of the type MTD_UBIVOLUME.

A speculative pointer dereference problem exists in the Linux Kernel on the do_prlimit() function. The resource argument value is controlled and is used in pointer arithmetic for the 'rlim' variable and can be used to leak the contents. We recommend upgrading past version 6.1.8 or commit 739790605705ddcf18f21782b9c99ad7d53a8c11

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: psi: Add check for kstrdup Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: f2fs: split initial and dynamic conditions for extent_cache Let's allocate the extent_cache tree without dynamic conditions to avoid a missing condition causing a panic as below. # create a file w/ a compressed flag # disable the compression # panic while updating extent_cache F2FS-fs (dm-64): Swapfile: last extent is not aligned to section F2FS-fs (dm-64): Swapfile (3) is not align to section: 1) creat(), 2) ioctl(F2FS_IOC_SET_PIN_FILE), 3) fallocate(2097152 * N) Adding 124996k swap on ./swap-file. Priority:0 extents:2 across:17179494468k ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read_write out/common/include/linux/instrumented.h:101 [inline] BUG: KASAN: null-ptr-deref in atomic_try_cmpxchg_acquire out/common/include/asm-generic/atomic-instrumented.h:705 [inline] BUG: KASAN: null-ptr-deref in queued_write_lock out/common/include/asm-generic/qrwlock.h:92 [inline] BUG: KASAN: null-ptr-deref in __raw_write_lock out/common/include/linux/rwlock_api_smp.h:211 [inline] BUG: KASAN: null-ptr-deref in _raw_write_lock+0x5a/0x110 out/common/kernel/locking/spinlock.c:295 Write of size 4 at addr 0000000000000030 by task syz-executor154/3327 CPU: 0 PID: 3327 Comm: syz-executor154 Tainted: G O 5.10.185 #1 Hardware name: emulation qemu-x86/qemu-x86, BIOS 2023.01-21885-gb3cc1cd24d 01/01/2023 Call Trace: __dump_stack out/common/lib/dump_stack.c:77 [inline] dump_stack_lvl+0x17e/0x1c4 out/common/lib/dump_stack.c:118 __kasan_report+0x16c/0x260 out/common/mm/kasan/report.c:415 kasan_report+0x51/0x70 out/common/mm/kasan/report.c:428 kasan_check_range+0x2f3/0x340 out/common/mm/kasan/generic.c:186 __kasan_check_write+0x14/0x20 out/common/mm/kasan/shadow.c:37 instrument_atomic_read_write out/common/include/linux/instrumented.h:101 [inline] atomic_try_cmpxchg_acquire out/common/include/asm-generic/atomic-instrumented.h:705 [inline] queued_write_lock out/common/include/asm-generic/qrwlock.h:92 [inline] __raw_write_lock out/common/include/linux/rwlock_api_smp.h:211 [inline] _raw_write_lock+0x5a/0x110 out/common/kernel/locking/spinlock.c:295 __drop_extent_tree+0xdf/0x2f0 out/common/fs/f2fs/extent_cache.c:1155 f2fs_drop_extent_tree+0x17/0x30 out/common/fs/f2fs/extent_cache.c:1172 f2fs_insert_range out/common/fs/f2fs/file.c:1600 [inline] f2fs_fallocate+0x19fd/0x1f40 out/common/fs/f2fs/file.c:1764 vfs_fallocate+0x514/0x9b0 out/common/fs/open.c:310 ksys_fallocate out/common/fs/open.c:333 [inline] __do_sys_fallocate out/common/fs/open.c:341 [inline] __se_sys_fallocate out/common/fs/open.c:339 [inline] __x64_sys_fallocate+0xb8/0x100 out/common/fs/open.c:339 do_syscall_64+0x35/0x50 out/common/arch/x86/entry/common.c:46

A NULL pointer dereference flaw was found in the Linux kernel's GPU Nouveau driver functionality in versions prior to 5.12-rc1 in the way the user calls ioctl DRM_IOCTL_NOUVEAU_CHANNEL_ALLOC. This flaw allows a local user to crash the system.

The netfilter subsystem in the Linux kernel through 4.15.7 mishandles the case of a rule blob that contains a jump but lacks a user-defined chain, which allows local users to cause a denial of service (NULL pointer dereference) by leveraging the CAP_NET_RAW or CAP_NET_ADMIN capability, related to arpt_do_table in net/ipv4/netfilter/arp_tables.c, ipt_do_table in net/ipv4/netfilter/ip_tables.c, and ip6t_do_table in net/ipv6/netfilter/ip6_tables.c.

An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in btrfs_root_node() when mounting a crafted btrfs image, because of a lack of chunk block group mapping validation in btrfs_read_block_groups in fs/btrfs/extent-tree.c, and a lack of empty-tree checks in check_leaf in fs/btrfs/tree-checker.c.

A race condition between hugetlb sysctl handlers in mm/hugetlb.c in the Linux kernel before 5.8.8 could be used by local attackers to corrupt memory, cause a NULL pointer dereference, or possibly have unspecified other impact, aka CID-17743798d812.

In modem-ps-nas-ngmm, there is a possible undefined behavior due to incorrect error handling. This could lead to remote information disclosure no additional execution privileges needed

A NULL pointer dereference vulnerability in the Linux kernel NVMe functionality, in nvmet_setup_auth(), allows an attacker to perform a Pre-Auth Denial of Service (DoS) attack on a remote machine. Affected versions v6.0-rc1 to v6.0-rc3, fixed in v6.0-rc4.

The hi3660_stub_clk_probe function in drivers/clk/hisilicon/clk-hi3660-stub.c in the Linux kernel before 4.16 allows local users to cause a denial of service (NULL pointer dereference) by triggering a failure of resource retrieval.