In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/cs: make commands with 0 chunks illegal behaviour. Submitting a cs with 0 chunks, causes an oops later, found trying to execute the wrong userspace driver. MESA_LOADER_DRIVER_OVERRIDE=v3d glxinfo [172536.665184] BUG: kernel NULL pointer dereference, address: 00000000000001d8 [172536.665188] #PF: supervisor read access in kernel mode [172536.665189] #PF: error_code(0x0000) - not-present page [172536.665191] PGD 6712a0067 P4D 6712a0067 PUD 5af9ff067 PMD 0 [172536.665195] Oops: 0000 [#1] SMP NOPTI [172536.665197] CPU: 7 PID: 2769838 Comm: glxinfo Tainted: P O 5.10.81 #1-NixOS [172536.665199] Hardware name: To be filled by O.E.M. To be filled by O.E.M./CROSSHAIR V FORMULA-Z, BIOS 2201 03/23/2015 [172536.665272] RIP: 0010:amdgpu_cs_ioctl+0x96/0x1ce0 [amdgpu] [172536.665274] Code: 75 18 00 00 4c 8b b2 88 00 00 00 8b 46 08 48 89 54 24 68 49 89 f7 4c 89 5c 24 60 31 d2 4c 89 74 24 30 85 c0 0f 85 c0 01 00 00 <48> 83 ba d8 01 00 00 00 48 8b b4 24 90 00 00 00 74 16 48 8b 46 10 [172536.665276] RSP: 0018:ffffb47c0e81bbe0 EFLAGS: 00010246 [172536.665277] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [172536.665278] RDX: 0000000000000000 RSI: ffffb47c0e81be28 RDI: ffffb47c0e81bd68 [172536.665279] RBP: ffff936524080010 R08: 0000000000000000 R09: ffffb47c0e81be38 [172536.665281] R10: ffff936524080010 R11: ffff936524080000 R12: ffffb47c0e81bc40 [172536.665282] R13: ffffb47c0e81be28 R14: ffff9367bc410000 R15: ffffb47c0e81be28 [172536.665283] FS: 00007fe35e05d740(0000) GS:ffff936c1edc0000(0000) knlGS:0000000000000000 [172536.665284] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [172536.665286] CR2: 00000000000001d8 CR3: 0000000532e46000 CR4: 00000000000406e0 [172536.665287] Call Trace: [172536.665322] ? amdgpu_cs_find_mapping+0x110/0x110 [amdgpu] [172536.665332] drm_ioctl_kernel+0xaa/0xf0 [drm] [172536.665338] drm_ioctl+0x201/0x3b0 [drm] [172536.665369] ? amdgpu_cs_find_mapping+0x110/0x110 [amdgpu] [172536.665372] ? selinux_file_ioctl+0x135/0x230 [172536.665399] amdgpu_drm_ioctl+0x49/0x80 [amdgpu] [172536.665403] __x64_sys_ioctl+0x83/0xb0 [172536.665406] do_syscall_64+0x33/0x40 [172536.665409] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/2018
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Add a dc_state NULL check in dc_state_release [How] Check wheather state is NULL before releasing it.
In the Linux kernel, the following vulnerability has been resolved: net, neigh: Fix null-ptr-deref in neigh_table_clear() When IPv6 module gets initialized but hits an error in the middle, kenel panic with: KASAN: null-ptr-deref in range [0x0000000000000598-0x000000000000059f] CPU: 1 PID: 361 Comm: insmod Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:__neigh_ifdown.isra.0+0x24b/0x370 RSP: 0018:ffff888012677908 EFLAGS: 00000202 ... Call Trace: <TASK> neigh_table_clear+0x94/0x2d0 ndisc_cleanup+0x27/0x40 [ipv6] inet6_init+0x21c/0x2cb [ipv6] do_one_initcall+0xd3/0x4d0 do_init_module+0x1ae/0x670 ... Kernel panic - not syncing: Fatal exception When ipv6 initialization fails, it will try to cleanup and calls: neigh_table_clear() neigh_ifdown(tbl, NULL) pneigh_queue_purge(&tbl->proxy_queue, dev_net(dev == NULL)) # dev_net(NULL) triggers null-ptr-deref. Fix it by passing NULL to pneigh_queue_purge() in neigh_ifdown() if dev is NULL, to make kernel not panic immediately.
In the Linux kernel, the following vulnerability has been resolved: ath11k: disable spectral scan during spectral deinit When ath11k modules are removed using rmmod with spectral scan enabled, crash is observed. Different crash trace is observed for each crash. Send spectral scan disable WMI command to firmware before cleaning the spectral dbring in the spectral_deinit API to avoid this crash. call trace from one of the crash observed: [ 1252.880802] Unable to handle kernel NULL pointer dereference at virtual address 00000008 [ 1252.882722] pgd = 0f42e886 [ 1252.890955] [00000008] *pgd=00000000 [ 1252.893478] Internal error: Oops: 5 [#1] PREEMPT SMP ARM [ 1253.093035] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.89 #0 [ 1253.115261] Hardware name: Generic DT based system [ 1253.121149] PC is at ath11k_spectral_process_data+0x434/0x574 [ath11k] [ 1253.125940] LR is at 0x88e31017 [ 1253.132448] pc : [<7f9387b8>] lr : [<88e31017>] psr: a0000193 [ 1253.135488] sp : 80d01bc8 ip : 00000001 fp : 970e0000 [ 1253.141737] r10: 88e31000 r9 : 970ec000 r8 : 00000080 [ 1253.146946] r7 : 94734040 r6 : a0000113 r5 : 00000057 r4 : 00000000 [ 1253.152159] r3 : e18cb694 r2 : 00000217 r1 : 1df1f000 r0 : 00000001 [ 1253.158755] Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user [ 1253.165266] Control: 10c0383d Table: 5e71006a DAC: 00000055 [ 1253.172472] Process swapper/0 (pid: 0, stack limit = 0x60870141) [ 1253.458055] [<7f9387b8>] (ath11k_spectral_process_data [ath11k]) from [<7f917fdc>] (ath11k_dbring_buffer_release_event+0x214/0x2e4 [ath11k]) [ 1253.466139] [<7f917fdc>] (ath11k_dbring_buffer_release_event [ath11k]) from [<7f8ea3c4>] (ath11k_wmi_tlv_op_rx+0x1840/0x29cc [ath11k]) [ 1253.478807] [<7f8ea3c4>] (ath11k_wmi_tlv_op_rx [ath11k]) from [<7f8fe868>] (ath11k_htc_rx_completion_handler+0x180/0x4e0 [ath11k]) [ 1253.490699] [<7f8fe868>] (ath11k_htc_rx_completion_handler [ath11k]) from [<7f91308c>] (ath11k_ce_per_engine_service+0x2c4/0x3b4 [ath11k]) [ 1253.502386] [<7f91308c>] (ath11k_ce_per_engine_service [ath11k]) from [<7f9a4198>] (ath11k_pci_ce_tasklet+0x28/0x80 [ath11k_pci]) [ 1253.514811] [<7f9a4198>] (ath11k_pci_ce_tasklet [ath11k_pci]) from [<8032227c>] (tasklet_action_common.constprop.2+0x64/0xe8) [ 1253.526476] [<8032227c>] (tasklet_action_common.constprop.2) from [<803021e8>] (__do_softirq+0x130/0x2d0) [ 1253.537756] [<803021e8>] (__do_softirq) from [<80322610>] (irq_exit+0xcc/0xe8) [ 1253.547304] [<80322610>] (irq_exit) from [<8036a4a4>] (__handle_domain_irq+0x60/0xb4) [ 1253.554428] [<8036a4a4>] (__handle_domain_irq) from [<805eb348>] (gic_handle_irq+0x4c/0x90) [ 1253.562321] [<805eb348>] (gic_handle_irq) from [<80301a78>] (__irq_svc+0x58/0x8c) Tested-on: QCN6122 hw1.0 AHB WLAN.HK.2.6.0.1-00851-QCAHKSWPL_SILICONZ-1
In the Linux kernel, the following vulnerability has been resolved: crypto: octeontx2 - remove CONFIG_DM_CRYPT check No issues were found while using the driver with dm-crypt enabled. So CONFIG_DM_CRYPT check in the driver can be removed. This also fixes the NULL pointer dereference in driver release if CONFIG_DM_CRYPT is enabled. ... Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 ... Call trace: crypto_unregister_alg+0x68/0xfc crypto_unregister_skciphers+0x44/0x60 otx2_cpt_crypto_exit+0x100/0x1a0 otx2_cptvf_remove+0xf8/0x200 pci_device_remove+0x3c/0xd4 __device_release_driver+0x188/0x234 device_release_driver+0x2c/0x4c ...
In the Linux kernel, the following vulnerability has been resolved: drm/msm/dp: populate connector of struct dp_panel DP CTS test case 4.2.2.6 has valid edid with bad checksum on purpose and expect DP source return correct checksum. During drm edid read, correct edid checksum is calculated and stored at connector::real_edid_checksum. The problem is struct dp_panel::connector never be assigned, instead the connector is stored in struct msm_dp::connector. When we run compliance testing test case 4.2.2.6 dp_panel_handle_sink_request() won't have a valid edid set in struct dp_panel::edid so we'll try to use the connectors real_edid_checksum and hit a NULL pointer dereference error because the connector pointer is never assigned. Changes in V2: -- populate panel connector at msm_dp_modeset_init() instead of at dp_panel_read_sink_caps() Changes in V3: -- remove unhelpful kernel crash trace commit text -- remove renaming dp_display parameter to dp Changes in V4: -- add more details to commit text Changes in v10: -- group into one series Changes in v11: -- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read Signee-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
In the Linux kernel, the following vulnerability has been resolved: soc: ti: ti_sci_pm_domains: Check for null return of devm_kcalloc The allocation funciton devm_kcalloc may fail and return a null pointer, which would cause a null-pointer dereference later. It might be better to check it and directly return -ENOMEM just like the usage of devm_kcalloc in previous code.
In the Linux kernel, the following vulnerability has been resolved: mt76: mt7921: fix kernel crash at mt7921_pci_remove The crash log shown it is possible that mt7921_irq_handler is called while devm_free_irq is being handled so mt76_free_device need to be postponed until devm_free_irq is completed to solve the crash we free the mt76 device too early. [ 9299.339655] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 9299.339705] #PF: supervisor read access in kernel mode [ 9299.339735] #PF: error_code(0x0000) - not-present page [ 9299.339768] PGD 0 P4D 0 [ 9299.339786] Oops: 0000 [#1] SMP PTI [ 9299.339812] CPU: 1 PID: 1624 Comm: prepare-suspend Not tainted 5.15.14-1.fc32.qubes.x86_64 #1 [ 9299.339863] Hardware name: Xen HVM domU, BIOS 4.14.3 01/20/2022 [ 9299.339901] RIP: 0010:mt7921_irq_handler+0x1e/0x70 [mt7921e] [ 9299.340048] RSP: 0018:ffffa81b80c27cb0 EFLAGS: 00010082 [ 9299.340081] RAX: 0000000000000000 RBX: ffff98a4cb752020 RCX: ffffffffa96211c5 [ 9299.340123] RDX: 0000000000000000 RSI: 00000000000d4204 RDI: ffff98a4cb752020 [ 9299.340165] RBP: ffff98a4c28a62a4 R08: ffff98a4c37a96c0 R09: 0000000080150011 [ 9299.340207] R10: 0000000040000000 R11: 0000000000000000 R12: ffff98a4c4eaa080 [ 9299.340249] R13: ffff98a4c28a6360 R14: ffff98a4cb752020 R15: ffff98a4c28a6228 [ 9299.340297] FS: 00007260840d3740(0000) GS:ffff98a4ef700000(0000) knlGS:0000000000000000 [ 9299.340345] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9299.340383] CR2: 0000000000000008 CR3: 0000000004c56001 CR4: 0000000000770ee0 [ 9299.340432] PKRU: 55555554 [ 9299.340449] Call Trace: [ 9299.340467] <TASK> [ 9299.340485] __free_irq+0x221/0x350 [ 9299.340527] free_irq+0x30/0x70 [ 9299.340553] devm_free_irq+0x55/0x80 [ 9299.340579] mt7921_pci_remove+0x2f/0x40 [mt7921e] [ 9299.340616] pci_device_remove+0x3b/0xa0 [ 9299.340651] __device_release_driver+0x17a/0x240 [ 9299.340686] device_driver_detach+0x3c/0xa0 [ 9299.340714] unbind_store+0x113/0x130 [ 9299.340740] kernfs_fop_write_iter+0x124/0x1b0 [ 9299.340775] new_sync_write+0x15c/0x1f0 [ 9299.340806] vfs_write+0x1d2/0x270 [ 9299.340831] ksys_write+0x67/0xe0 [ 9299.340857] do_syscall_64+0x3b/0x90 [ 9299.340887] entry_SYSCALL_64_after_hwframe+0x44/0xae
In the Linux kernel, the following vulnerability has been resolved: net: mediatek: Fix potential NULL pointer dereference in dummy net_device handling Move the freeing of the dummy net_device from mtk_free_dev() to mtk_remove(). Previously, if alloc_netdev_dummy() failed in mtk_probe(), eth->dummy_dev would be NULL. The error path would then call mtk_free_dev(), which in turn called free_netdev() assuming dummy_dev was allocated (but it was not), potentially causing a NULL pointer dereference. By moving free_netdev() to mtk_remove(), we ensure it's only called when mtk_probe() has succeeded and dummy_dev is fully allocated. This addresses a potential NULL pointer dereference detected by Smatch[1].
In the Linux kernel, the following vulnerability has been resolved: net: phy: at803x: fix NULL pointer dereference on AR9331 PHY Latest kernel will explode on the PHY interrupt config, since it depends now on allocated priv. So, run probe to allocate priv to fix it. ar9331_switch ethernet.1:10 lan0 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:00] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) CPU 0 Unable to handle kernel paging request at virtual address 0000000a, epc == 8050e8a8, ra == 80504b34 ... Call Trace: [<8050e8a8>] at803x_config_intr+0x5c/0xd0 [<80504b34>] phy_request_interrupt+0xa8/0xd0 [<8050289c>] phylink_bringup_phy+0x2d8/0x3ac [<80502b68>] phylink_fwnode_phy_connect+0x118/0x130 [<8074d8ec>] dsa_slave_create+0x270/0x420 [<80743b04>] dsa_port_setup+0x12c/0x148 [<8074580c>] dsa_register_switch+0xaf0/0xcc0 [<80511344>] ar9331_sw_probe+0x370/0x388 [<8050cb78>] mdio_probe+0x44/0x70 [<804df300>] really_probe+0x200/0x424 [<804df7b4>] __driver_probe_device+0x290/0x298 [<804df810>] driver_probe_device+0x54/0xe4 [<804dfd50>] __device_attach_driver+0xe4/0x130 [<804dcb00>] bus_for_each_drv+0xb4/0xd8 [<804dfac4>] __device_attach+0x104/0x1a4 [<804ddd24>] bus_probe_device+0x48/0xc4 [<804deb44>] deferred_probe_work_func+0xf0/0x10c [<800a0ffc>] process_one_work+0x314/0x4d4 [<800a17fc>] worker_thread+0x2a4/0x354 [<800a9a54>] kthread+0x134/0x13c [<8006306c>] ret_from_kernel_thread+0x14/0x1c Same Issue would affect some other PHYs (QCA8081, QCA9561), so fix it too.
In Dekart Private Disk 2.15, invalid use of the Type3 user buffer for IOCTL codes using METHOD_NEITHER results in arbitrary memory dereferencing.
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix null deref accessing lag dev It could be the lag dev is null so stop processing the event. In bond_enslave() the active/backup slave being set before setting the upper dev so first event is without an upper dev. After setting the upper dev with bond_master_upper_dev_link() there is a second event and in that event we have an upper dev.
Zemana AntiLogger v2.74.204.664 is vulnerable to a Denial of Service (DoS) vulnerability by triggering the 0x80002004 and 0x80002010 IOCTL codes of the zam64.sys and zamguard64.sys drivers.
In the Linux kernel, the following vulnerability has been resolved: bonding: fix NULL deref in bond_rr_gen_slave_id Fix a NULL dereference of the struct bonding.rr_tx_counter member because if a bond is initially created with an initial mode != zero (Round Robin) the memory required for the counter is never created and when the mode is changed there is never any attempt to verify the memory is allocated upon switching modes. This causes the following Oops on an aarch64 machine: [ 334.686773] Unable to handle kernel paging request at virtual address ffff2c91ac905000 [ 334.694703] Mem abort info: [ 334.697486] ESR = 0x0000000096000004 [ 334.701234] EC = 0x25: DABT (current EL), IL = 32 bits [ 334.706536] SET = 0, FnV = 0 [ 334.709579] EA = 0, S1PTW = 0 [ 334.712719] FSC = 0x04: level 0 translation fault [ 334.717586] Data abort info: [ 334.720454] ISV = 0, ISS = 0x00000004 [ 334.724288] CM = 0, WnR = 0 [ 334.727244] swapper pgtable: 4k pages, 48-bit VAs, pgdp=000008044d662000 [ 334.733944] [ffff2c91ac905000] pgd=0000000000000000, p4d=0000000000000000 [ 334.740734] Internal error: Oops: 96000004 [#1] SMP [ 334.745602] Modules linked in: bonding tls veth rfkill sunrpc arm_spe_pmu vfat fat acpi_ipmi ipmi_ssif ixgbe igb i40e mdio ipmi_devintf ipmi_msghandler arm_cmn arm_dsu_pmu cppc_cpufreq acpi_tad fuse zram crct10dif_ce ast ghash_ce sbsa_gwdt nvme drm_vram_helper drm_ttm_helper nvme_core ttm xgene_hwmon [ 334.772217] CPU: 7 PID: 2214 Comm: ping Not tainted 6.0.0-rc4-00133-g64ae13ed4784 #4 [ 334.779950] Hardware name: GIGABYTE R272-P31-00/MP32-AR1-00, BIOS F18v (SCP: 1.08.20211002) 12/01/2021 [ 334.789244] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 334.796196] pc : bond_rr_gen_slave_id+0x40/0x124 [bonding] [ 334.801691] lr : bond_xmit_roundrobin_slave_get+0x38/0xdc [bonding] [ 334.807962] sp : ffff8000221733e0 [ 334.811265] x29: ffff8000221733e0 x28: ffffdbac8572d198 x27: ffff80002217357c [ 334.818392] x26: 000000000000002a x25: ffffdbacb33ee000 x24: ffff07ff980fa000 [ 334.825519] x23: ffffdbacb2e398ba x22: ffff07ff98102000 x21: ffff07ff981029c0 [ 334.832646] x20: 0000000000000001 x19: ffff07ff981029c0 x18: 0000000000000014 [ 334.839773] x17: 0000000000000000 x16: ffffdbacb1004364 x15: 0000aaaabe2f5a62 [ 334.846899] x14: ffff07ff8e55d968 x13: ffff07ff8e55db30 x12: 0000000000000000 [ 334.854026] x11: ffffdbacb21532e8 x10: 0000000000000001 x9 : ffffdbac857178ec [ 334.861153] x8 : ffff07ff9f6e5a28 x7 : 0000000000000000 x6 : 000000007c2b3742 [ 334.868279] x5 : ffff2c91ac905000 x4 : ffff2c91ac905000 x3 : ffff07ff9f554400 [ 334.875406] x2 : ffff2c91ac905000 x1 : 0000000000000001 x0 : ffff07ff981029c0 [ 334.882532] Call trace: [ 334.884967] bond_rr_gen_slave_id+0x40/0x124 [bonding] [ 334.890109] bond_xmit_roundrobin_slave_get+0x38/0xdc [bonding] [ 334.896033] __bond_start_xmit+0x128/0x3a0 [bonding] [ 334.901001] bond_start_xmit+0x54/0xb0 [bonding] [ 334.905622] dev_hard_start_xmit+0xb4/0x220 [ 334.909798] __dev_queue_xmit+0x1a0/0x720 [ 334.913799] arp_xmit+0x3c/0xbc [ 334.916932] arp_send_dst+0x98/0xd0 [ 334.920410] arp_solicit+0xe8/0x230 [ 334.923888] neigh_probe+0x60/0xb0 [ 334.927279] __neigh_event_send+0x3b0/0x470 [ 334.931453] neigh_resolve_output+0x70/0x90 [ 334.935626] ip_finish_output2+0x158/0x514 [ 334.939714] __ip_finish_output+0xac/0x1a4 [ 334.943800] ip_finish_output+0x40/0xfc [ 334.947626] ip_output+0xf8/0x1a4 [ 334.950931] ip_send_skb+0x5c/0x100 [ 334.954410] ip_push_pending_frames+0x3c/0x60 [ 334.958758] raw_sendmsg+0x458/0x6d0 [ 334.962325] inet_sendmsg+0x50/0x80 [ 334.965805] sock_sendmsg+0x60/0x6c [ 334.969286] __sys_sendto+0xc8/0x134 [ 334.972853] __arm64_sys_sendto+0x34/0x4c ---truncated---
NULL Pointer Dereference vulnerability in Linux Linux kernel kernel on Linux, x86, ARM (net, bluetooth modules) allows Overflow Buffers. This vulnerability is associated with program files /net/bluetooth/rfcomm/core.C. This issue affects Linux kernel: v2.6.12-rc2.
In the Linux kernel, the following vulnerability has been resolved: s390/mm: Add NULL pointer check to crst_table_free() base_crst_free() crst_table_free() used to work with NULL pointers before the conversion to ptdescs. Since crst_table_free() can be called with a NULL pointer (error handling in crst_table_upgrade() add an explicit check. Also add the same check to base_crst_free() for consistency reasons. In real life this should not happen, since order two GFP_KERNEL allocations will not fail, unless FAIL_PAGE_ALLOC is enabled and used.
In the Linux kernel, the following vulnerability has been resolved: gpio: Restrict usage of GPIO chip irq members before initialization GPIO chip irq members are exposed before they could be completely initialized and this leads to race conditions. One such issue was observed for the gc->irq.domain variable which was accessed through the I2C interface in gpiochip_to_irq() before it could be initialized by gpiochip_add_irqchip(). This resulted in Kernel NULL pointer dereference. Following are the logs for reference :- kernel: Call Trace: kernel: gpiod_to_irq+0x53/0x70 kernel: acpi_dev_gpio_irq_get_by+0x113/0x1f0 kernel: i2c_acpi_get_irq+0xc0/0xd0 kernel: i2c_device_probe+0x28a/0x2a0 kernel: really_probe+0xf2/0x460 kernel: RIP: 0010:gpiochip_to_irq+0x47/0xc0 To avoid such scenarios, restrict usage of GPIO chip irq members before they are completely initialized.
In the Linux kernel, the following vulnerability has been resolved: clk: sunxi-ng: common: Don't call hw_to_ccu_common on hw without common In order to set the rate range of a hw sunxi_ccu_probe calls hw_to_ccu_common() assuming all entries in desc->ccu_clks are contained in a ccu_common struct. This assumption is incorrect and, in consequence, causes invalid pointer de-references. Remove the faulty call. Instead, add one more loop that iterates over the ccu_clks and sets the rate range, if required.
In the Linux kernel, the following vulnerability has been resolved: ice: fix NULL pointer dereference in ice_update_vsi_tx_ring_stats() It is possible to do NULL pointer dereference in routine that updates Tx ring stats. Currently only stats and bytes are updated when ring pointer is valid, but later on ring is accessed to propagate gathered Tx stats onto VSI stats. Change the existing logic to move to next ring when ring is NULL.
In the Linux kernel, the following vulnerability has been resolved: drm/gma500: fix null pointer dereference in psb_intel_lvds_get_modes In psb_intel_lvds_get_modes(), the return value of drm_mode_duplicate() is assigned to mode, which will lead to a possible NULL pointer dereference on failure of drm_mode_duplicate(). Add a check to avoid npd.
A security flaw has been discovered in GPAC up to 2.4.0. Affected by this vulnerability is the function DumpMovieInfo of the file applications/mp4box/filedump.c. The manipulation results in null pointer dereference. The attack must be initiated from a local position. The exploit has been released to the public and may be used for attacks. The patch is identified as d45c264c20addf0c1cc05124ede33f8ffa800e68. It is advisable to implement a patch to correct this issue.
In the Linux kernel, the following vulnerability has been resolved: media: imx-pxp: Fix ERR_PTR dereference in pxp_probe() devm_regmap_init_mmio() can fail, add a check and bail out in case of error.
In the Linux kernel, the following vulnerability has been resolved: thermal/drivers/mediatek/lvts_thermal: Check NULL ptr on lvts_data Verify that lvts_data is not NULL before using it.
In the Linux kernel, the following vulnerability has been resolved: s390/dasd: Fix invalid dereferencing of indirect CCW data pointer Fix invalid dereferencing of indirect CCW data pointer in dasd_eckd_dump_sense() that leads to a kernel panic in error cases. When using indirect addressing for DASD CCWs (IDAW) the CCW CDA pointer does not contain the data address itself but a pointer to the IDAL. This needs to be translated from physical to virtual as well before using it. This dereferencing is also used for dasd_page_cache and also fixed although it is very unlikely that this code path ever gets used.
A vulnerability has been identified in SIMATIC S7-PLCSIM V5.4 (All versions). An attacker with local access to the system could cause a Denial-of-Service condition in the application when it is used to open a specially crafted file. As a consequence, a NULL pointer deference condition could cause the application to terminate unexpectedly and must be restarted to restore the service.
In the Linux kernel, the following vulnerability has been resolved: xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr() ip6_dst_idev() can return NULL, xfrm6_get_saddr() must act accordingly. syzbot reported: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker RIP: 0010:xfrm6_get_saddr+0x93/0x130 net/ipv6/xfrm6_policy.c:64 Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 97 00 00 00 4c 8b ab d8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 00 00 00 4d 8b 6d 00 e8 ca 13 47 01 48 b8 00 RSP: 0018:ffffc90000117378 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88807b079dc0 RCX: ffffffff89a0d6d7 RDX: 0000000000000000 RSI: ffffffff89a0d6e9 RDI: ffff88807b079e98 RBP: ffff88807ad73248 R08: 0000000000000007 R09: fffffffffffff000 R10: ffff88807b079dc0 R11: 0000000000000007 R12: ffffc90000117480 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4586d00440 CR3: 0000000079042000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> xfrm_get_saddr net/xfrm/xfrm_policy.c:2452 [inline] xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2481 [inline] xfrm_tmpl_resolve+0xa26/0xf10 net/xfrm/xfrm_policy.c:2541 xfrm_resolve_and_create_bundle+0x140/0x2570 net/xfrm/xfrm_policy.c:2835 xfrm_bundle_lookup net/xfrm/xfrm_policy.c:3070 [inline] xfrm_lookup_with_ifid+0x4d1/0x1e60 net/xfrm/xfrm_policy.c:3201 xfrm_lookup net/xfrm/xfrm_policy.c:3298 [inline] xfrm_lookup_route+0x3b/0x200 net/xfrm/xfrm_policy.c:3309 ip6_dst_lookup_flow+0x15c/0x1d0 net/ipv6/ip6_output.c:1256 send6+0x611/0xd20 drivers/net/wireguard/socket.c:139 wg_socket_send_skb_to_peer+0xf9/0x220 drivers/net/wireguard/socket.c:178 wg_socket_send_buffer_to_peer+0x12b/0x190 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation+0x227/0x360 drivers/net/wireguard/send.c:40 wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
In the Linux kernel, the following vulnerability has been resolved: qede: confirm skb is allocated before using qede_build_skb() assumes build_skb() always works and goes straight to skb_reserve(). However, build_skb() can fail under memory pressure. This results in a kernel panic because the skb to reserve is NULL. Add a check in case build_skb() failed to allocate and return NULL. The NULL return is handled correctly in callers to qede_build_skb().
In the Linux kernel, the following vulnerability has been resolved: thermal/int340x_thermal: handle data_vault when the value is ZERO_SIZE_PTR In some case, the GDDV returns a package with a buffer which has zero length. It causes that kmemdup() returns ZERO_SIZE_PTR (0x10). Then the data_vault_read() got NULL point dereference problem when accessing the 0x10 value in data_vault. [ 71.024560] BUG: kernel NULL pointer dereference, address: 0000000000000010 This patch uses ZERO_OR_NULL_PTR() for checking ZERO_SIZE_PTR or NULL value in data_vault.
A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was assumed to be associated with a device before calling __ip_options_compile, which is not always the case if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash the system.
NULL pointer dereference vulnerability in ION driver prior to SMR Sep-2021 Release 1 allows attackers to cause memory corruption.
In the Linux kernel, the following vulnerability has been resolved: drm/nouveau/dispnv04: fix null pointer dereference in nv17_tv_get_ld_modes In nv17_tv_get_ld_modes(), the return value of drm_mode_duplicate() is assigned to mode, which will lead to a possible NULL pointer dereference on failure of drm_mode_duplicate(). Add a check to avoid npd.
In the Linux kernel, the following vulnerability has been resolved: ACPICA: Revert "ACPICA: avoid Info: mapping multiple BARs. Your kernel is fine." Undo the modifications made in commit d410ee5109a1 ("ACPICA: avoid "Info: mapping multiple BARs. Your kernel is fine.""). The initial purpose of this commit was to stop memory mappings for operation regions from overlapping page boundaries, as it can trigger warnings if different page attributes are present. However, it was found that when this situation arises, mapping continues until the boundary's end, but there is still an attempt to read/write the entire length of the map, leading to a NULL pointer deference. For example, if a four-byte mapping request is made but only one byte is mapped because it hits the current page boundary's end, a four-byte read/write attempt is still made, resulting in a NULL pointer deference. Instead, map the entire length, as the ACPI specification does not mandate that it must be within the same page boundary. It is permissible for it to be mapped across different regions.
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: avoid using null object of framebuffer Instead of using state->fb->obj[0] directly, get object from framebuffer by calling drm_gem_fb_get_obj() and return error code when object is null to avoid using null object of framebuffer.
In the Linux kernel, the following vulnerability has been resolved: media: mtk-vcodec: potential null pointer deference in SCP The return value of devm_kzalloc() needs to be checked to avoid NULL pointer deference. This is similar to CVE-2022-3113.
In the Linux kernel, the following vulnerability has been resolved: null_blk: fix validation of block size Block size should be between 512 and PAGE_SIZE and be a power of 2. The current check does not validate this, so update the check. Without this patch, null_blk would Oops due to a null pointer deref when loaded with bs=1536 [1]. [axboe: remove unnecessary braces and != 0 check]
In the Linux kernel, the following vulnerability has been resolved: seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors input_action_end_dx4() and input_action_end_dx6() are called NF_HOOK() for PREROUTING hook, in PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), otherwise may trigger a NULL pointer dereference, as below: [74830.647293] BUG: kernel NULL pointer dereference, address: 0000000000000090 [74830.655633] #PF: supervisor read access in kernel mode [74830.657888] #PF: error_code(0x0000) - not-present page [74830.659500] PGD 0 P4D 0 [74830.660450] Oops: 0000 [#1] PREEMPT SMP PTI ... [74830.664953] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [74830.666569] RIP: 0010:rpfilter_mt+0x44/0x15e [ipt_rpfilter] ... [74830.689725] Call Trace: [74830.690402] <IRQ> [74830.690953] ? show_trace_log_lvl+0x1c4/0x2df [74830.692020] ? show_trace_log_lvl+0x1c4/0x2df [74830.693095] ? ipt_do_table+0x286/0x710 [ip_tables] [74830.694275] ? __die_body.cold+0x8/0xd [74830.695205] ? page_fault_oops+0xac/0x140 [74830.696244] ? exc_page_fault+0x62/0x150 [74830.697225] ? asm_exc_page_fault+0x22/0x30 [74830.698344] ? rpfilter_mt+0x44/0x15e [ipt_rpfilter] [74830.699540] ipt_do_table+0x286/0x710 [ip_tables] [74830.700758] ? ip6_route_input+0x19d/0x240 [74830.701752] nf_hook_slow+0x3f/0xb0 [74830.702678] input_action_end_dx4+0x19b/0x1e0 [74830.703735] ? input_action_end_t+0xe0/0xe0 [74830.704734] seg6_local_input_core+0x2d/0x60 [74830.705782] lwtunnel_input+0x5b/0xb0 [74830.706690] __netif_receive_skb_one_core+0x63/0xa0 [74830.707825] process_backlog+0x99/0x140 [74830.709538] __napi_poll+0x2c/0x160 [74830.710673] net_rx_action+0x296/0x350 [74830.711860] __do_softirq+0xcb/0x2ac [74830.713049] do_softirq+0x63/0x90 input_action_end_dx4() passing a NULL indev to NF_HOOK(), and finally trigger a NULL dereference in rpfilter_mt()->rpfilter_is_loopback(): static bool rpfilter_is_loopback(const struct sk_buff *skb, const struct net_device *in) { // in is NULL return skb->pkt_type == PACKET_LOOPBACK || in->flags & IFF_LOOPBACK; }
NULL pointer dereference in Intel(R) Power Gadget software for Windows all versions may allow an authenticated user to potentially enable denial of service via local access.
A security flaw has been discovered in ckolivas lrzip up to 0.651. This impacts the function __GI_____strtol_l_internal of the file strtol_l.c. Performing manipulation results in null pointer dereference. The attack is only possible with local access. The exploit has been released to the public and may be exploited.
In the Linux kernel, the following vulnerability has been resolved: net: ethtool: fix the error condition in ethtool_get_phy_stats_ethtool() Clang static checker (scan-build) warning: net/ethtool/ioctl.c:line 2233, column 2 Called function pointer is null (null dereference). Return '-EOPNOTSUPP' when 'ops->get_ethtool_phy_stats' is NULL to fix this typo error.
In the Linux kernel, the following vulnerability has been resolved: netfs: Fix netfs_page_mkwrite() to check folio->mapping is valid Fix netfs_page_mkwrite() to check that folio->mapping is valid once it has taken the folio lock (as filemap_page_mkwrite() does). Without this, generic/247 occasionally oopses with something like the following: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page RIP: 0010:trace_event_raw_event_netfs_folio+0x61/0xc0 ... Call Trace: <TASK> ? __die_body+0x1a/0x60 ? page_fault_oops+0x6e/0xa0 ? exc_page_fault+0xc2/0xe0 ? asm_exc_page_fault+0x22/0x30 ? trace_event_raw_event_netfs_folio+0x61/0xc0 trace_netfs_folio+0x39/0x40 netfs_page_mkwrite+0x14c/0x1d0 do_page_mkwrite+0x50/0x90 do_pte_missing+0x184/0x200 __handle_mm_fault+0x42d/0x500 handle_mm_fault+0x121/0x1f0 do_user_addr_fault+0x23e/0x3c0 exc_page_fault+0xc2/0xe0 asm_exc_page_fault+0x22/0x30 This is due to the invalidate_inode_pages2_range() issued at the end of the DIO write interfering with the mmap'd writes.
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix NULL pointer dereference in ocfs2_journal_dirty() bdev->bd_super has been removed and commit 8887b94d9322 change the usage from bdev->bd_super to b_assoc_map->host->i_sb. This introduces the following NULL pointer dereference in ocfs2_journal_dirty() since b_assoc_map is still not initialized. This can be easily reproduced by running xfstests generic/186, which simulate no more credits. [ 134.351592] BUG: kernel NULL pointer dereference, address: 0000000000000000 ... [ 134.355341] RIP: 0010:ocfs2_journal_dirty+0x14f/0x160 [ocfs2] ... [ 134.365071] Call Trace: [ 134.365312] <TASK> [ 134.365524] ? __die_body+0x1e/0x60 [ 134.365868] ? page_fault_oops+0x13d/0x4f0 [ 134.366265] ? __pfx_bit_wait_io+0x10/0x10 [ 134.366659] ? schedule+0x27/0xb0 [ 134.366981] ? exc_page_fault+0x6a/0x140 [ 134.367356] ? asm_exc_page_fault+0x26/0x30 [ 134.367762] ? ocfs2_journal_dirty+0x14f/0x160 [ocfs2] [ 134.368305] ? ocfs2_journal_dirty+0x13d/0x160 [ocfs2] [ 134.368837] ocfs2_create_new_meta_bhs.isra.51+0x139/0x2e0 [ocfs2] [ 134.369454] ocfs2_grow_tree+0x688/0x8a0 [ocfs2] [ 134.369927] ocfs2_split_and_insert.isra.67+0x35c/0x4a0 [ocfs2] [ 134.370521] ocfs2_split_extent+0x314/0x4d0 [ocfs2] [ 134.371019] ocfs2_change_extent_flag+0x174/0x410 [ocfs2] [ 134.371566] ocfs2_add_refcount_flag+0x3fa/0x630 [ocfs2] [ 134.372117] ocfs2_reflink_remap_extent+0x21b/0x4c0 [ocfs2] [ 134.372994] ? inode_update_timestamps+0x4a/0x120 [ 134.373692] ? __pfx_ocfs2_journal_access_di+0x10/0x10 [ocfs2] [ 134.374545] ? __pfx_ocfs2_journal_access_di+0x10/0x10 [ocfs2] [ 134.375393] ocfs2_reflink_remap_blocks+0xe4/0x4e0 [ocfs2] [ 134.376197] ocfs2_remap_file_range+0x1de/0x390 [ocfs2] [ 134.376971] ? security_file_permission+0x29/0x50 [ 134.377644] vfs_clone_file_range+0xfe/0x320 [ 134.378268] ioctl_file_clone+0x45/0xa0 [ 134.378853] do_vfs_ioctl+0x457/0x990 [ 134.379422] __x64_sys_ioctl+0x6e/0xd0 [ 134.379987] do_syscall_64+0x5d/0x170 [ 134.380550] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 134.381231] RIP: 0033:0x7fa4926397cb [ 134.381786] Code: 73 01 c3 48 8b 0d bd 56 38 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8d 56 38 00 f7 d8 64 89 01 48 [ 134.383930] RSP: 002b:00007ffc2b39f7b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 134.384854] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fa4926397cb [ 134.385734] RDX: 00007ffc2b39f7f0 RSI: 000000004020940d RDI: 0000000000000003 [ 134.386606] RBP: 0000000000000000 R08: 00111a82a4f015bb R09: 00007fa494221000 [ 134.387476] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 134.388342] R13: 0000000000f10000 R14: 0000558e844e2ac8 R15: 0000000000f10000 [ 134.389207] </TASK> Fix it by only aborting transaction and journal in ocfs2_journal_dirty() now, and leave ocfs2_abort() later when detecting an aborted handle, e.g. start next transaction. Also log the handle details in this case.
A vulnerability, which was classified as problematic, was found in spdlog up to 1.15.1. This affects the function scoped_padder in the library include/spdlog/pattern_formatter-inl.h. The manipulation leads to resource consumption. It is possible to launch the attack on the local host. The exploit has been disclosed to the public and may be used. Upgrading to version 1.15.2 is able to address this issue. The identifier of the patch is 10320184df1eb4638e253a34b1eb44ce78954094. It is recommended to upgrade the affected component.
In the Linux kernel, the following vulnerability has been resolved: net: mana: Fix possible double free in error handling path When auxiliary_device_add() returns error and then calls auxiliary_device_uninit(), callback function adev_release calls kfree(madev). We shouldn't call kfree(madev) again in the error handling path. Set 'madev' to NULL.
In the Linux kernel, the following vulnerability has been resolved: drm/xe/xe_devcoredump: Check NULL before assignments Assign 'xe_devcoredump_snapshot *' and 'xe_device *' only if 'coredump' is not NULL. v2 - Fix commit messages. v3 - Define variables before code.(Ashutosh/Jose) v4 - Drop return check for coredump_to_xe. (Jose/Rodrigo) v5 - Modify misleading commit message. (Matt)
In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: Intel: hda: fix null deref on system suspend entry When system enters suspend with an active stream, SOF core calls hw_params_upon_resume(). On Intel platforms with HDA DMA used to manage the link DMA, this leads to call chain of hda_dsp_set_hw_params_upon_resume() -> hda_dsp_dais_suspend() -> hda_dai_suspend() -> hda_ipc4_post_trigger() A bug is hit in hda_dai_suspend() as hda_link_dma_cleanup() is run first, which clears hext_stream->link_substream, and then hda_ipc4_post_trigger() is called with a NULL snd_pcm_substream pointer.
In the Linux kernel, the following vulnerability has been resolved: skmsg: Skip zero length skb in sk_msg_recvmsg When running BPF selftests (./test_progs -t sockmap_basic) on a Loongarch platform, the following kernel panic occurs: [...] Oops[#1]: CPU: 22 PID: 2824 Comm: test_progs Tainted: G OE 6.10.0-rc2+ #18 Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018 ... ... ra: 90000000048bf6c0 sk_msg_recvmsg+0x120/0x560 ERA: 9000000004162774 copy_page_to_iter+0x74/0x1c0 CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) PRMD: 0000000c (PPLV0 +PIE +PWE) EUEN: 00000007 (+FPE +SXE +ASXE -BTE) ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7) ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0) BADV: 0000000000000040 PRID: 0014c011 (Loongson-64bit, Loongson-3C5000) Modules linked in: bpf_testmod(OE) xt_CHECKSUM xt_MASQUERADE xt_conntrack Process test_progs (pid: 2824, threadinfo=0000000000863a31, task=...) Stack : ... Call Trace: [<9000000004162774>] copy_page_to_iter+0x74/0x1c0 [<90000000048bf6c0>] sk_msg_recvmsg+0x120/0x560 [<90000000049f2b90>] tcp_bpf_recvmsg_parser+0x170/0x4e0 [<90000000049aae34>] inet_recvmsg+0x54/0x100 [<900000000481ad5c>] sock_recvmsg+0x7c/0xe0 [<900000000481e1a8>] __sys_recvfrom+0x108/0x1c0 [<900000000481e27c>] sys_recvfrom+0x1c/0x40 [<9000000004c076ec>] do_syscall+0x8c/0xc0 [<9000000003731da4>] handle_syscall+0xc4/0x160 Code: ... ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Fatal exception Kernel relocated by 0x3510000 .text @ 0x9000000003710000 .data @ 0x9000000004d70000 .bss @ 0x9000000006469400 ---[ end Kernel panic - not syncing: Fatal exception ]--- [...] This crash happens every time when running sockmap_skb_verdict_shutdown subtest in sockmap_basic. This crash is because a NULL pointer is passed to page_address() in the sk_msg_recvmsg(). Due to the different implementations depending on the architecture, page_address(NULL) will trigger a panic on Loongarch platform but not on x86 platform. So this bug was hidden on x86 platform for a while, but now it is exposed on Loongarch platform. The root cause is that a zero length skb (skb->len == 0) was put on the queue. This zero length skb is a TCP FIN packet, which was sent by shutdown(), invoked in test_sockmap_skb_verdict_shutdown(): shutdown(p1, SHUT_WR); In this case, in sk_psock_skb_ingress_enqueue(), num_sge is zero, and no page is put to this sge (see sg_set_page in sg_set_page), but this empty sge is queued into ingress_msg list. And in sk_msg_recvmsg(), this empty sge is used, and a NULL page is got by sg_page(sge). Pass this NULL page to copy_page_to_iter(), which passes it to kmap_local_page() and to page_address(), then kernel panics. To solve this, we should skip this zero length skb. So in sk_msg_recvmsg(), if copy is zero, that means it's a zero length skb, skip invoking copy_page_to_iter(). We are using the EFAULT return triggered by copy_page_to_iter to check for is_fin in tcp_bpf.c.
In the Linux kernel, the following vulnerability has been resolved: ALSA: hda: cs35l41: Possible null pointer dereference in cs35l41_hda_unbind() The cs35l41_hda_unbind() function clears the hda_component entry matching it's index and then dereferences the codec pointer held in the first element of the hda_component array, this is an issue when the device index was 0. Instead use the codec pointer stashed in the cs35l41_hda structure as it will still be valid.
In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: ipc4-topology: Fix input format query of process modules without base extension If a process module does not have base config extension then the same format applies to all of it's inputs and the process->base_config_ext is NULL, causing NULL dereference when specifically crafted topology and sequences used.
An incorrect permissions vulnerability was reported in the Lenovo App Store app that could allow an attacker to use system resources, resulting in a denial of service.
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.