NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: md-cluster: fix NULL pointer dereference in process_metadata_update The function process_metadata_update() blindly dereferences the 'thread' pointer (acquired via rcu_dereference_protected) within the wait_event() macro. While the code comment states "daemon thread must exist", there is a valid race condition window during the MD array startup sequence (md_run): 1. bitmap_load() is called, which invokes md_cluster_ops->join(). 2. join() starts the "cluster_recv" thread (recv_daemon). 3. At this point, recv_daemon is active and processing messages. 4. However, mddev->thread (the main MD thread) is not initialized until later in md_run(). If a METADATA_UPDATED message is received from a remote node during this specific window, process_metadata_update() will be called while mddev->thread is still NULL, leading to a kernel panic. To fix this, we must validate the 'thread' pointer. If it is NULL, we release the held lock (no_new_dev_lockres) and return early, safely ignoring the update request as the array is not yet fully ready to process it.Show less

In the Linux kernel, the following vulnerability has been resolved: media: chips-media: wave5: Fix Null reference while testing fluster When multi instances are created/destroyed, many interrupts happens and structures for decoder are removed. "struct vpu_instance" this structure is shared for all flow in the decoder, so if the structure is not protected by lock, Null dereference could happens sometimes. IRQ Handler was spilt to two phases and Lock was added as well.Show less

In the Linux kernel, the following vulnerability has been resolved: HID: prodikeys: Check presence of pm->input_ep82 Fake USB devices can send their own report descriptors for which the input_mapping() hook does not get called. In this case, pm->input_ep82 stays NULL, which leads to a crash later. This does not happen with the real device, but can be provoked by imposing as one.Show less

In the Linux kernel, the following vulnerability has been resolved: net: Drop the lock in skb_may_tx_timestamp() skb_may_tx_timestamp() may acquire sock::sk_callback_lock. The lock must not be taken in IRQ context, only softirq is okay. A few drivers receive the timestamp via a dedicated interrupt and complete the TX timestamp from that handler. This will lead to a deadlock if the lock is already write-locked on the same CPU. Taking the lock can be avoided. The socket (pointed by the skb) will remain valid until the skb is released. The ->sk_socket and ->file member will be set to NULL once the user closes the socket which may happen before the timestamp arrives. If we happen to observe the pointer while the socket is closing but before the pointer is set to NULL then we may use it because both pointer (and the file's cred member) are RCU freed. Drop the lock. Use READ_ONCE() to obtain the individual pointer. Add a matching WRITE_ONCE() where the pointer are cleared.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: rtw89: pci: validate sequence number of TX release report Hardware rarely reports abnormal sequence number in TX release report, which will access out-of-bounds of wd_ring->pages array, causing NULL pointer dereference. BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 1085 Comm: irq/129-rtw89_p Tainted: G S U 6.1.145-17510-g2f3369c91536 #1 (HASH:69e8 1) Call Trace: <IRQ> rtw89_pci_release_tx+0x18f/0x300 [rtw89_pci (HASH:4c83 2)] rtw89_pci_napi_poll+0xc2/0x190 [rtw89_pci (HASH:4c83 2)] net_rx_action+0xfc/0x460 net/core/dev.c:6578 net/core/dev.c:6645 net/core/dev.c:6759 handle_softirqs+0xbe/0x290 kernel/softirq.c:601 ? rtw89_pci_interrupt_threadfn+0xc5/0x350 [rtw89_pci (HASH:4c83 2)] __local_bh_enable_ip+0xeb/0x120 kernel/softirq.c:499 kernel/softirq.c:423 </IRQ> <TASK> rtw89_pci_interrupt_threadfn+0xf8/0x350 [rtw89_pci (HASH:4c83 2)] ? irq_thread+0xa7/0x340 kernel/irq/manage.c:0 irq_thread+0x177/0x340 kernel/irq/manage.c:1205 kernel/irq/manage.c:1314 ? thaw_kernel_threads+0xb0/0xb0 kernel/irq/manage.c:1202 ? irq_forced_thread_fn+0x80/0x80 kernel/irq/manage.c:1220 kthread+0xea/0x110 kernel/kthread.c:376 ? synchronize_irq+0x1a0/0x1a0 kernel/irq/manage.c:1287 ? kthread_associate_blkcg+0x80/0x80 kernel/kthread.c:331 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> To prevent crash, validate rpp_info.seq before using.Show less

In the Linux kernel, the following vulnerability has been resolved: media: mtk-mdp: Fix error handling in probe function Add mtk_mdp_unregister_m2m_device() on the error handling path to prevent resource leak. Add check for the return value of vpu_get_plat_device() to prevent null pointer dereference. And vpu_get_plat_device() increases the reference count of the returned platform device. Add platform_device_put() to prevent reference leak.Show less

In the Linux kernel, the following vulnerability has been resolved: clk: rs9: Reserve 8 struct clk_hw slots for for 9FGV0841 The 9FGV0841 has 8 outputs and registers 8 struct clk_hw, make sure there are 8 slots for those newly registered clk_hw pointers, else there is going to be out of bounds write when pointers 4..7 are set into struct rs9_driver_data .clk_dif[4..7] field. Since there are other structure members past this struct clk_hw pointer array, writing to .clk_dif[4..7] fields corrupts both the struct rs9_driver_data content and data around it, sometimes without crashing the kernel. However, the kernel does surely crash when the driver is unbound or during suspend. Fix this, increase the struct clk_hw pointer array size to the maximum output count of 9FGV0841, which is the biggest chip that is supported by this driver.Show less

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: xscale: Check for PTP support properly In ixp4xx_get_ts_info() ixp46x_ptp_find() is called unconditionally despite this feature only existing on ixp46x, leading to the following splat from tcpdump: root@OpenWrt:~# tcpdump -vv -X -i eth0 (...) Unable to handle kernel NULL pointer dereference at virtual address 00000238 when read (...) Call trace: ptp_clock_index from ixp46x_ptp_find+0x1c/0x38 ixp46x_ptp_find from ixp4xx_get_ts_info+0x4c/0x64 ixp4xx_get_ts_info from __ethtool_get_ts_info+0x90/0x108 __ethtool_get_ts_info from __dev_ethtool+0xa00/0x2648 __dev_ethtool from dev_ethtool+0x160/0x234 dev_ethtool from dev_ioctl+0x2cc/0x460 dev_ioctl from sock_ioctl+0x1ec/0x524 sock_ioctl from sys_ioctl+0x51c/0xa94 sys_ioctl from ret_fast_syscall+0x0/0x44 (...) Segmentation fault Check for ixp46x in ixp46x_ptp_find() before trying to set up PTP to avoid this. To avoid altering the returned error code from ixp4xx_hwtstamp_set() which before this patch was -EOPNOTSUPP, we return -EOPNOTSUPP from ixp4xx_hwtstamp_set() if ixp46x_ptp_find() fails no matter the error code. The helper function ixp46x_ptp_find() helper returns -ENODEV.Show less

In the Linux kernel, the following vulnerability has been resolved: udplite: Fix null-ptr-deref in __udp_enqueue_schedule_skb(). syzbot reported null-ptr-deref of udp_sk(sk)->udp_prod_queue. [0] Since the cited commit, udp_lib_init_sock() can fail, as can udp_init_sock() and udpv6_init_sock(). Let's handle the error in udplite_sk_init() and udplitev6_sk_init(). [0]: BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:82 [inline] BUG: KASAN: null-ptr-deref in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: null-ptr-deref in __udp_enqueue_schedule_skb+0x151/0x1480 net/ipv4/udp.c:1719 Read of size 4 at addr 0000000000000008 by task syz.2.18/2944 CPU: 1 UID: 0 PID: 2944 Comm: syz.2.18 Not tainted syzkaller #0 PREEMPTLAZY Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: <IRQ> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 kasan_report+0xa2/0xe0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200 instrument_atomic_read include/linux/instrumented.h:82 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] __udp_enqueue_schedule_skb+0x151/0x1480 net/ipv4/udp.c:1719 __udpv6_queue_rcv_skb net/ipv6/udp.c:795 [inline] udpv6_queue_rcv_one_skb+0xa2e/0x1ad0 net/ipv6/udp.c:906 udp6_unicast_rcv_skb+0x227/0x380 net/ipv6/udp.c:1064 ip6_protocol_deliver_rcu+0xe17/0x1540 net/ipv6/ip6_input.c:438 ip6_input_finish+0x191/0x350 net/ipv6/ip6_input.c:489 NF_HOOK+0x354/0x3f0 include/linux/netfilter.h:318 ip6_input+0x16c/0x2b0 net/ipv6/ip6_input.c:500 NF_HOOK+0x354/0x3f0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6149 [inline] __netif_receive_skb+0xd3/0x370 net/core/dev.c:6262 process_backlog+0x4d6/0x1160 net/core/dev.c:6614 __napi_poll+0xae/0x320 net/core/dev.c:7678 napi_poll net/core/dev.c:7741 [inline] net_rx_action+0x60d/0xdc0 net/core/dev.c:7893 handle_softirqs+0x209/0x8d0 kernel/softirq.c:622 do_softirq+0x52/0x90 kernel/softirq.c:523 </IRQ> <TASK> __local_bh_enable_ip+0xe7/0x120 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline] __dev_queue_xmit+0x109c/0x2dc0 net/core/dev.c:4856 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x158/0x4e0 net/ipv6/ip6_output.c:219 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip6_output+0x342/0x580 net/ipv6/ip6_output.c:246 ip6_send_skb+0x1d7/0x3c0 net/ipv6/ip6_output.c:1984 udp_v6_send_skb+0x9a5/0x1770 net/ipv6/udp.c:1442 udp_v6_push_pending_frames+0xa2/0x140 net/ipv6/udp.c:1469 udpv6_sendmsg+0xfe0/0x2830 net/ipv6/udp.c:1759 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xe5/0x270 net/socket.c:742 __sys_sendto+0x3eb/0x580 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0xf20 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f67b4d9c629 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f67b5c98028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f67b5015fa0 RCX: 00007f67b4d9c629 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f67b4e32b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000040000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f67b5016038 R14: 00007f67b5015fa0 R15: 00007ffe3cb66dd8 </TASK>Show less

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix null dereference in find_network The variable pwlan has the possibility of being NULL when passed into rtw_free_network_nolock() which would later dereference the variable.Show less

In the Linux kernel, the following vulnerability has been resolved: powerpc/smp: Add check for kcalloc() failure in parse_thread_groups() As kcalloc() may fail, check its return value to avoid a NULL pointer dereference when passing it to of_property_read_u32_array().Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix potential kernel oops when probe fails When probe of the sdio brcmfmac device fails for some reasons (i.e. missing firmware), the sdiodev->bus is set to error instead of NULL, thus the cleanup later in brcmf_sdio_remove() tries to free resources via invalid bus pointer. This happens because sdiodev->bus is set 2 times: first in brcmf_sdio_probe() and second time in brcmf_sdiod_probe(). Fix this by chaning the brcmf_sdio_probe() function to return the error code and set sdio->bus only there.Show less

In the Linux kernel, the following vulnerability has been resolved: HID: magicmouse: Do not crash on missing msc->input Fake USB devices can send their own report descriptors for which the input_mapping() hook does not get called. In this case, msc->input stays NULL, leading to a crash at a later time. Detect this condition in the input_configured() hook and reject the device. This is not supposed to happen with actual magic mouse devices, but can be provoked by imposing as a magic mouse USB device.Show less

In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: Intel: hda: Fix NULL pointer dereference If there's a mismatch between the DAI links in the machine driver and the topology, it is possible that the playback/capture widget is not set, especially in the case of loopback capture for echo reference where we use the dummy DAI link. Return the error when the widget is not set to avoid a null pointer dereference like below when the topology is broken. RIP: 0010:hda_dai_get_ops.isra.0+0x14/0xa0 [snd_sof_intel_hda_common]Show less

In the Linux kernel, the following vulnerability has been resolved: pstore: ram_core: fix incorrect success return when vmap() fails In persistent_ram_vmap(), vmap() may return NULL on failure. If offset is non-zero, adding offset_in_page(start) causes the function to return a non-NULL pointer even though the mapping failed. persistent_ram_buffer_map() therefore incorrectly returns success. Subsequent access to prz->buffer may dereference an invalid address and cause crashes. Add proper NULL checking for vmap() failures.Show less

In the Linux kernel, the following vulnerability has been resolved: fbcon: check return value of con2fb_acquire_newinfo() If fbcon_open() fails when called from con2fb_acquire_newinfo() then info->fbcon_par pointer remains NULL which is later dereferenced. Add check for return value of the function con2fb_acquire_newinfo() to avoid it. Found by Linux Verification Center (linuxtesting.org) with SVACE.Show less

In the Linux kernel, the following vulnerability has been resolved: fs/buffer: add alert in try_to_free_buffers() for folios without buffers try_to_free_buffers() can be called on folios with no buffers attached when filemap_release_folio() is invoked on a folio belonging to a mapping with AS_RELEASE_ALWAYS set but no release_folio operation defined. In such cases, folio_needs_release() returns true because of the AS_RELEASE_ALWAYS flag, but the folio has no private buffer data. This causes try_to_free_buffers() to call drop_buffers() on a folio with no buffers, leading to a null pointer dereference. Adding a check in try_to_free_buffers() to return early if the folio has no buffers attached, with WARN_ON_ONCE() to alert about the misconfiguration. This provides defensive hardening.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix NULL pointer issue buffer funcs If SDMA block not enabled, buffer_funcs will not initialize, fix the null pointer issue if buffer_funcs not initialized.Show less