NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: ftrace: Fix null pointer dereference in ftrace_add_mod() The @ftrace_mod is allocated by kzalloc(), so both the members {prev,next} of @ftrace_mode->list are NULL, it's not a valid state to call list_del(). If kstrdup() for @ftrace_mod->{func|module} fails, it goes to @out_free tag and calls free_ftrace_mod() to destroy @ftrace_mod, then list_del() will write prev->next and next->prev, where null pointer dereference happens. BUG: kernel NULL pointer dereference, address: 0000000000000008 Oops: 0002 [#1] PREEMPT SMP NOPTI Call Trace: <TASK> ftrace_mod_callback+0x20d/0x220 ? do_filp_open+0xd9/0x140 ftrace_process_regex.isra.51+0xbf/0x130 ftrace_regex_write.isra.52.part.53+0x6e/0x90 vfs_write+0xee/0x3a0 ? __audit_filter_op+0xb1/0x100 ? auditd_test_task+0x38/0x50 ksys_write+0xa5/0xe0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Kernel panic - not syncing: Fatal exception So call INIT_LIST_HEAD() to initialize the list member to fix this issue.Show less

In the Linux kernel, the following vulnerability has been resolved: tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit() When trace_get_event_file() failed, gen_kretprobe_test will be assigned as the error code. If module kprobe_event_gen_test is removed now, the null pointer dereference will happen in kprobe_event_gen_test_exit(). Check if gen_kprobe_test or gen_kretprobe_test is error code or NULL before dereference them. BUG: kernel NULL pointer dereference, address: 0000000000000012 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 3 PID: 2210 Comm: modprobe Not tainted 6.1.0-rc1-00171-g2159299a3b74-dirty #217 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:kprobe_event_gen_test_exit+0x1c/0xb5 [kprobe_event_gen_test] Code: Unable to access opcode bytes at 0xffffffff9ffffff2. RSP: 0018:ffffc900015bfeb8 EFLAGS: 00010246 RAX: ffffffffffffffea RBX: ffffffffa0002080 RCX: 0000000000000000 RDX: ffffffffa0001054 RSI: ffffffffa0001064 RDI: ffffffffdfc6349c RBP: ffffffffa0000000 R08: 0000000000000004 R09: 00000000001e95c0 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000800 R13: ffffffffa0002420 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f56b75be540(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff9ffffff2 CR3: 000000010874a006 CR4: 0000000000330ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __x64_sys_delete_module+0x206/0x380 ? lockdep_hardirqs_on_prepare+0xd8/0x190 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcdShow less

In the Linux kernel, the following vulnerability has been resolved: tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() When test_gen_kprobe_cmd() failed after kprobe_event_gen_cmd_end(), it will goto delete, which will call kprobe_event_delete() and release the corresponding resource. However, the trace_array in gen_kretprobe_test will point to the invalid resource. Set gen_kretprobe_test to NULL after called kprobe_event_delete() to prevent null-ptr-deref. BUG: kernel NULL pointer dereference, address: 0000000000000070 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 246 Comm: modprobe Tainted: G W 6.1.0-rc1-00174-g9522dc5c87da-dirty #248 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:__ftrace_set_clr_event_nolock+0x53/0x1b0 Code: e8 82 26 fc ff 49 8b 1e c7 44 24 0c ea ff ff ff 49 39 de 0f 84 3c 01 00 00 c7 44 24 18 00 00 00 00 e8 61 26 fc ff 48 8b 6b 10 <44> 8b 65 70 4c 8b 6d 18 41 f7 c4 00 02 00 00 75 2f RSP: 0018:ffffc9000159fe00 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88810971d268 RCX: 0000000000000000 RDX: ffff8881080be600 RSI: ffffffff811b48ff RDI: ffff88810971d058 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffc9000159fe58 R11: 0000000000000001 R12: ffffffffa0001064 R13: ffffffffa000106c R14: ffff88810971d238 R15: 0000000000000000 FS: 00007f89eeff6540(0000) GS:ffff88813b600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000070 CR3: 000000010599e004 CR4: 0000000000330ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __ftrace_set_clr_event+0x3e/0x60 trace_array_set_clr_event+0x35/0x50 ? 0xffffffffa0000000 kprobe_event_gen_test_exit+0xcd/0x10b [kprobe_event_gen_test] __x64_sys_delete_module+0x206/0x380 ? lockdep_hardirqs_on_prepare+0xd8/0x190 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f89eeb061b7Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: Purge vif txq in ieee80211_do_stop() After ieee80211_do_stop() SKB from vif's txq could still be processed. Indeed another concurrent vif schedule_and_wake_txq call could cause those packets to be dequeued (see ieee80211_handle_wake_tx_queue()) without checking the sdata current state. Because vif.drv_priv is now cleared in this function, this could lead to driver crash. For example in ath12k, ahvif is store in vif.drv_priv. Thus if ath12k_mac_op_tx() is called after ieee80211_do_stop(), ahvif->ah can be NULL, leading the ath12k_warn(ahvif->ah,...) call in this function to trigger the NULL deref below. Unable to handle kernel paging request at virtual address dfffffc000000001 KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] batman_adv: bat0: Interface deactivated: brbh1337 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [dfffffc000000001] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] SMP CPU: 1 UID: 0 PID: 978 Comm: lbd Not tainted 6.13.0-g633f875b8f1e #114 Hardware name: HW (DT) pstate: 10000005 (nzcV daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : ath12k_mac_op_tx+0x6cc/0x29b8 [ath12k] lr : ath12k_mac_op_tx+0x174/0x29b8 [ath12k] sp : ffffffc086ace450 x29: ffffffc086ace450 x28: 0000000000000000 x27: 1ffffff810d59ca4 x26: ffffff801d05f7c0 x25: 0000000000000000 x24: 000000004000001e x23: ffffff8009ce4926 x22: ffffff801f9c0800 x21: ffffff801d05f7f0 x20: ffffff8034a19f40 x19: 0000000000000000 x18: ffffff801f9c0958 x17: ffffff800bc0a504 x16: dfffffc000000000 x15: ffffffc086ace4f8 x14: ffffff801d05f83c x13: 0000000000000000 x12: ffffffb003a0bf03 x11: 0000000000000000 x10: ffffffb003a0bf02 x9 : ffffff8034a19f40 x8 : ffffff801d05f818 x7 : 1ffffff0069433dc x6 : ffffff8034a19ee0 x5 : ffffff801d05f7f0 x4 : 0000000000000000 x3 : 0000000000000001 x2 : 0000000000000000 x1 : dfffffc000000000 x0 : 0000000000000008 Call trace: ath12k_mac_op_tx+0x6cc/0x29b8 [ath12k] (P) ieee80211_handle_wake_tx_queue+0x16c/0x260 ieee80211_queue_skb+0xeec/0x1d20 ieee80211_tx+0x200/0x2c8 ieee80211_xmit+0x22c/0x338 __ieee80211_subif_start_xmit+0x7e8/0xc60 ieee80211_subif_start_xmit+0xc4/0xee0 __ieee80211_subif_start_xmit_8023.isra.0+0x854/0x17a0 ieee80211_subif_start_xmit_8023+0x124/0x488 dev_hard_start_xmit+0x160/0x5a8 __dev_queue_xmit+0x6f8/0x3120 br_dev_queue_push_xmit+0x120/0x4a8 __br_forward+0xe4/0x2b0 deliver_clone+0x5c/0xd0 br_flood+0x398/0x580 br_dev_xmit+0x454/0x9f8 dev_hard_start_xmit+0x160/0x5a8 __dev_queue_xmit+0x6f8/0x3120 ip6_finish_output2+0xc28/0x1b60 __ip6_finish_output+0x38c/0x638 ip6_output+0x1b4/0x338 ip6_local_out+0x7c/0xa8 ip6_send_skb+0x7c/0x1b0 ip6_push_pending_frames+0x94/0xd0 rawv6_sendmsg+0x1a98/0x2898 inet_sendmsg+0x94/0xe0 __sys_sendto+0x1e4/0x308 __arm64_sys_sendto+0xc4/0x140 do_el0_svc+0x110/0x280 el0_svc+0x20/0x60 el0t_64_sync_handler+0x104/0x138 el0t_64_sync+0x154/0x158 To avoid that, empty vif's txq at ieee80211_do_stop() so no packet could be dequeued after ieee80211_do_stop() (new packets cannot be queued because SDATA_STATE_RUNNING is cleared at this point).Show less

In the Linux kernel, the following vulnerability has been resolved: ASoC: Intel: avs: Fix null-ptr-deref in avs_component_probe() devm_kasprintf() returns NULL when memory allocation fails. Currently, avs_component_probe() does not check for this case, which results in a NULL pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btrtl: Prevent potential NULL dereference The btrtl_initialize() function checks that rtl_load_file() either had an error or it loaded a zero length file. However, if it loaded a zero length file then the error code is not set correctly. It results in an error pointer vs NULL bug, followed by a NULL pointer dereference. This was detected by Smatch: drivers/bluetooth/btrtl.c:592 btrtl_initialize() warn: passing zero to 'ERR_PTR'Show less

In the Linux kernel, the following vulnerability has been resolved: net: dsa: mv88e6xxx: avoid unregistering devlink regions which were never registered Russell King reports that a system with mv88e6xxx dereferences a NULL pointer when unbinding this driver: https://lore.kernel.org/netdev/Z_lRkMlTJ1KQ0kVX@shell.armlinux.org.uk/ The crash seems to be in devlink_region_destroy(), which is not NULL tolerant but is given a NULL devlink global region pointer. At least on some chips, some devlink regions are conditionally registered since the blamed commit, see mv88e6xxx_setup_devlink_regions_global(): if (cond && !cond(chip)) continue; These are MV88E6XXX_REGION_STU and MV88E6XXX_REGION_PVT. If the chip does not have an STU or PVT, it should crash like this. To fix the issue, avoid unregistering those regions which are NULL, i.e. were skipped at mv88e6xxx_setup_devlink_regions_global() time.Show less

In the Linux kernel, the following vulnerability has been resolved: net: ti: icss-iep: Fix possible NULL pointer dereference for perout request The ICSS IEP driver tracks perout and pps enable state with flags. Currently when disabling pps and perout signals during icss_iep_exit(), results in NULL pointer dereference for perout. To fix the null pointer dereference issue, the icss_iep_perout_enable_hw function can be modified to directly clear the IEP CMP registers when disabling PPS or PEROUT, without referencing the ptp_perout_request structure, as its contents are irrelevant in this case.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Fix error pointers in dpu_plane_virtual_atomic_check The function dpu_plane_virtual_atomic_check was dereferencing pointers returned by drm_atomic_get_plane_state without checking for errors. This could lead to undefined behavior if the function returns an error pointer. This commit adds checks using IS_ERR to ensure that plane_state is valid before dereferencing them. Similar to commit da29abe71e16 ("drm/amd/display: Fix error pointers in amdgpu_dm_crtc_mem_type_changed"). Patchwork: https://patchwork.freedesktop.org/patch/643132/Show less

In the Linux kernel, the following vulnerability has been resolved: i2c: cros-ec-tunnel: defer probe if parent EC is not present When i2c-cros-ec-tunnel and the EC driver are built-in, the EC parent device will not be found, leading to NULL pointer dereference. That can also be reproduced by unbinding the controller driver and then loading i2c-cros-ec-tunnel module (or binding the device). [ 271.991245] BUG: kernel NULL pointer dereference, address: 0000000000000058 [ 271.998215] #PF: supervisor read access in kernel mode [ 272.003351] #PF: error_code(0x0000) - not-present page [ 272.008485] PGD 0 P4D 0 [ 272.011022] Oops: Oops: 0000 [#1] SMP NOPTI [ 272.015207] CPU: 0 UID: 0 PID: 3859 Comm: insmod Tainted: G S 6.15.0-rc1-00004-g44722359ed83 #30 PREEMPT(full) 3c7fb39a552e7d949de2ad921a7d6588d3a4fdc5 [ 272.030312] Tainted: [S]=CPU_OUT_OF_SPEC [ 272.034233] Hardware name: HP Berknip/Berknip, BIOS Google_Berknip.13434.356.0 05/17/2021 [ 272.042400] RIP: 0010:ec_i2c_probe+0x2b/0x1c0 [i2c_cros_ec_tunnel] [ 272.048577] Code: 1f 44 00 00 41 57 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 05 06 a0 6c e7 48 89 44 24 08 4c 8d 7f 10 48 8b 47 50 4c 8b 60 78 <49> 83 7c 24 58 00 0f 84 2f 01 00 00 48 89 fb be 30 06 00 00 4c 9 [ 272.067317] RSP: 0018:ffffa32082a03940 EFLAGS: 00010282 [ 272.072541] RAX: ffff969580b6a810 RBX: ffff969580b68c10 RCX: 0000000000000000 [ 272.079672] RDX: 0000000000000000 RSI: 0000000000000282 RDI: ffff969580b68c00 [ 272.086804] RBP: 00000000fffffdfb R08: 0000000000000000 R09: 0000000000000000 [ 272.093936] R10: 0000000000000000 R11: ffffffffc0600000 R12: 0000000000000000 [ 272.101067] R13: ffffffffa666fbb8 R14: ffffffffc05b5528 R15: ffff969580b68c10 [ 272.108198] FS: 00007b930906fc40(0000) GS:ffff969603149000(0000) knlGS:0000000000000000 [ 272.116282] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 272.122024] CR2: 0000000000000058 CR3: 000000012631c000 CR4: 00000000003506f0 [ 272.129155] Call Trace: [ 272.131606] <TASK> [ 272.133709] ? acpi_dev_pm_attach+0xdd/0x110 [ 272.137985] platform_probe+0x69/0xa0 [ 272.141652] really_probe+0x152/0x310 [ 272.145318] __driver_probe_device+0x77/0x110 [ 272.149678] driver_probe_device+0x1e/0x190 [ 272.153864] __driver_attach+0x10b/0x1e0 [ 272.157790] ? driver_attach+0x20/0x20 [ 272.161542] bus_for_each_dev+0x107/0x150 [ 272.165553] bus_add_driver+0x15d/0x270 [ 272.169392] driver_register+0x65/0x110 [ 272.173232] ? cleanup_module+0xa80/0xa80 [i2c_cros_ec_tunnel 3a00532f3f4af4a9eade753f86b0f8dd4e4e5698] [ 272.182617] do_one_initcall+0x110/0x350 [ 272.186543] ? security_kernfs_init_security+0x49/0xd0 [ 272.191682] ? __kernfs_new_node+0x1b9/0x240 [ 272.195954] ? security_kernfs_init_security+0x49/0xd0 [ 272.201093] ? __kernfs_new_node+0x1b9/0x240 [ 272.205365] ? kernfs_link_sibling+0x105/0x130 [ 272.209810] ? kernfs_next_descendant_post+0x1c/0xa0 [ 272.214773] ? kernfs_activate+0x57/0x70 [ 272.218699] ? kernfs_add_one+0x118/0x160 [ 272.222710] ? __kernfs_create_file+0x71/0xa0 [ 272.227069] ? sysfs_add_bin_file_mode_ns+0xd6/0x110 [ 272.232033] ? internal_create_group+0x453/0x4a0 [ 272.236651] ? __vunmap_range_noflush+0x214/0x2d0 [ 272.241355] ? __free_frozen_pages+0x1dc/0x420 [ 272.245799] ? free_vmap_area_noflush+0x10a/0x1c0 [ 272.250505] ? load_module+0x1509/0x16f0 [ 272.254431] do_init_module+0x60/0x230 [ 272.258181] __se_sys_finit_module+0x27a/0x370 [ 272.262627] do_syscall_64+0x6a/0xf0 [ 272.266206] ? do_syscall_64+0x76/0xf0 [ 272.269956] ? irqentry_exit_to_user_mode+0x79/0x90 [ 272.274836] entry_SYSCALL_64_after_hwframe+0x55/0x5d [ 272.279887] RIP: 0033:0x7b9309168d39 [ 272.283466] Code: 5b 41 5c 5d c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d af 40 0c 00 f7 d8 64 89 01 8 [ 272.302210] RSP: 002b:00007fff50f1a288 EFLAGS: 00000246 ORIG_RAX: 000 ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: slab: ensure slab->obj_exts is clear in a newly allocated slab page ktest recently reported crashes while running several buffered io tests with __alloc_tagging_slab_alloc_hook() at the top of the crash call stack. The signature indicates an invalid address dereference with low bits of slab->obj_exts being set. The bits were outside of the range used by page_memcg_data_flags and objext_flags and hence were not masked out by slab_obj_exts() when obtaining the pointer stored in slab->obj_exts. The typical crash log looks like this: 00510 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 00510 Mem abort info: 00510 ESR = 0x0000000096000045 00510 EC = 0x25: DABT (current EL), IL = 32 bits 00510 SET = 0, FnV = 0 00510 EA = 0, S1PTW = 0 00510 FSC = 0x05: level 1 translation fault 00510 Data abort info: 00510 ISV = 0, ISS = 0x00000045, ISS2 = 0x00000000 00510 CM = 0, WnR = 1, TnD = 0, TagAccess = 0 00510 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 00510 user pgtable: 4k pages, 39-bit VAs, pgdp=0000000104175000 00510 [0000000000000010] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000 00510 Internal error: Oops: 0000000096000045 [#1] SMP 00510 Modules linked in: 00510 CPU: 10 UID: 0 PID: 7692 Comm: cat Not tainted 6.15.0-rc1-ktest-g189e17946605 #19327 NONE 00510 Hardware name: linux,dummy-virt (DT) 00510 pstate: 20001005 (nzCv daif -PAN -UAO -TCO -DIT +SSBS BTYPE=--) 00510 pc : __alloc_tagging_slab_alloc_hook+0xe0/0x190 00510 lr : __kmalloc_noprof+0x150/0x310 00510 sp : ffffff80c87df6c0 00510 x29: ffffff80c87df6c0 x28: 000000000013d1ff x27: 000000000013d200 00510 x26: ffffff80c87df9e0 x25: 0000000000000000 x24: 0000000000000001 00510 x23: ffffffc08041953c x22: 000000000000004c x21: ffffff80c0002180 00510 x20: fffffffec3120840 x19: ffffff80c4821000 x18: 0000000000000000 00510 x17: fffffffec3d02f00 x16: fffffffec3d02e00 x15: fffffffec3d00700 00510 x14: fffffffec3d00600 x13: 0000000000000200 x12: 0000000000000006 00510 x11: ffffffc080bb86c0 x10: 0000000000000000 x9 : ffffffc080201e58 00510 x8 : ffffff80c4821060 x7 : 0000000000000000 x6 : 0000000055555556 00510 x5 : 0000000000000001 x4 : 0000000000000010 x3 : 0000000000000060 00510 x2 : 0000000000000000 x1 : ffffffc080f50cf8 x0 : ffffff80d801d000 00510 Call trace: 00510 __alloc_tagging_slab_alloc_hook+0xe0/0x190 (P) 00510 __kmalloc_noprof+0x150/0x310 00510 __bch2_folio_create+0x5c/0xf8 00510 bch2_folio_create+0x2c/0x40 00510 bch2_readahead+0xc0/0x460 00510 read_pages+0x7c/0x230 00510 page_cache_ra_order+0x244/0x3a8 00510 page_cache_async_ra+0x124/0x170 00510 filemap_readahead.isra.0+0x58/0xa0 00510 filemap_get_pages+0x454/0x7b0 00510 filemap_read+0xdc/0x418 00510 bch2_read_iter+0x100/0x1b0 00510 vfs_read+0x214/0x300 00510 ksys_read+0x6c/0x108 00510 __arm64_sys_read+0x20/0x30 00510 invoke_syscall.constprop.0+0x54/0xe8 00510 do_el0_svc+0x44/0xc8 00510 el0_svc+0x18/0x58 00510 el0t_64_sync_handler+0x104/0x130 00510 el0t_64_sync+0x154/0x158 00510 Code: d5384100 f9401c01 b9401aa3 b40002e1 (f8227881) 00510 ---[ end trace 0000000000000000 ]--- 00510 Kernel panic - not syncing: Oops: Fatal exception 00510 SMP: stopping secondary CPUs 00510 Kernel Offset: disabled 00510 CPU features: 0x0000,000000e0,00000410,8240500b 00510 Memory Limit: none Investigation indicates that these bits are already set when we allocate slab page and are not zeroed out after allocation. We are not yet sure why these crashes start happening only recently but regardless of the reason, not initializing a field that gets used later is wrong. Fix it by initializing slab->obj_exts during slab page allocation.Show less

In the Linux kernel, the following vulnerability has been resolved: RDMA/cma: Fix workqueue crash in cma_netevent_work_handler struct rdma_cm_id has member "struct work_struct net_work" that is reused for enqueuing cma_netevent_work_handler()s onto cma_wq. Below crash[1] can occur if more than one call to cma_netevent_callback() occurs in quick succession, which further enqueues cma_netevent_work_handler()s for the same rdma_cm_id, overwriting any previously queued work-item(s) that was just scheduled to run i.e. there is no guarantee the queued work item may run between two successive calls to cma_netevent_callback() and the 2nd INIT_WORK would overwrite the 1st work item (for the same rdma_cm_id), despite grabbing id_table_lock during enqueue. Also drgn analysis [2] indicates the work item was likely overwritten. Fix this by moving the INIT_WORK() to __rdma_create_id(), so that it doesn't race with any existing queue_work() or its worker thread. [1] Trimmed crash stack: ============================================= BUG: kernel NULL pointer dereference, address: 0000000000000008 kworker/u256:6 ... 6.12.0-0... Workqueue: cma_netevent_work_handler [rdma_cm] (rdma_cm) RIP: 0010:process_one_work+0xba/0x31a Call Trace: worker_thread+0x266/0x3a0 kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 ============================================= [2] drgn crash analysis: >>> trace = prog.crashed_thread().stack_trace() >>> trace (0) crash_setup_regs (./arch/x86/include/asm/kexec.h:111:15) (1) __crash_kexec (kernel/crash_core.c:122:4) (2) panic (kernel/panic.c:399:3) (3) oops_end (arch/x86/kernel/dumpstack.c:382:3) ... (8) process_one_work (kernel/workqueue.c:3168:2) (9) process_scheduled_works (kernel/workqueue.c:3310:3) (10) worker_thread (kernel/workqueue.c:3391:4) (11) kthread (kernel/kthread.c:389:9) Line workqueue.c:3168 for this kernel version is in process_one_work(): 3168 strscpy(worker->desc, pwq->wq->name, WORKER_DESC_LEN); >>> trace[8]["work"] *(struct work_struct *)0xffff92577d0a21d8 = { .data = (atomic_long_t){ .counter = (s64)536870912, <=== Note }, .entry = (struct list_head){ .next = (struct list_head *)0xffff924d075924c0, .prev = (struct list_head *)0xffff924d075924c0, }, .func = (work_func_t)cma_netevent_work_handler+0x0 = 0xffffffffc2cec280, } Suspicion is that pwq is NULL: >>> trace[8]["pwq"] (struct pool_workqueue *)<absent> In process_one_work(), pwq is assigned from: struct pool_workqueue *pwq = get_work_pwq(work); and get_work_pwq() is: static struct pool_workqueue *get_work_pwq(struct work_struct *work) { unsigned long data = atomic_long_read(&work->data); if (data & WORK_STRUCT_PWQ) return work_struct_pwq(data); else return NULL; } WORK_STRUCT_PWQ is 0x4: >>> print(repr(prog['WORK_STRUCT_PWQ'])) Object(prog, 'enum work_flags', value=4) But work->data is 536870912 which is 0x20000000. So, get_work_pwq() returns NULL and we crash in process_one_work(): 3168 strscpy(worker->desc, pwq->wq->name, WORKER_DESC_LEN); =============================================Show less

In the Linux kernel, the following vulnerability has been resolved: ublk: fix handling recovery & reissue in ublk_abort_queue() Commit 8284066946e6 ("ublk: grab request reference when the request is handled by userspace") doesn't grab request reference in case of recovery reissue. Then the request can be requeued & re-dispatch & failed when canceling uring command. If it is one zc request, the request can be freed before io_uring returns the zc buffer back, then cause kernel panic: [ 126.773061] BUG: kernel NULL pointer dereference, address: 00000000000000c8 [ 126.773657] #PF: supervisor read access in kernel mode [ 126.774052] #PF: error_code(0x0000) - not-present page [ 126.774455] PGD 0 P4D 0 [ 126.774698] Oops: Oops: 0000 [#1] SMP NOPTI [ 126.775034] CPU: 13 UID: 0 PID: 1612 Comm: kworker/u64:55 Not tainted 6.14.0_blk+ #182 PREEMPT(full) [ 126.775676] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 04/01/2014 [ 126.776275] Workqueue: iou_exit io_ring_exit_work [ 126.776651] RIP: 0010:ublk_io_release+0x14/0x130 [ublk_drv] Fixes it by always grabbing request reference for aborting the request.Show less

In the Linux kernel, the following vulnerability has been resolved: ata: pata_pxa: Fix potential NULL pointer dereference in pxa_ata_probe() devm_ioremap() returns NULL on error. Currently, pxa_ata_probe() does not check for this case, which can result in a NULL pointer dereference. Add NULL check after devm_ioremap() to prevent this issue.Show less

In the Linux kernel, the following vulnerability has been resolved: net: libwx: handle page_pool_dev_alloc_pages error page_pool_dev_alloc_pages could return NULL. There was a WARN_ON(!page) but it would still proceed to use the NULL pointer and then crash. This is similar to commit 001ba0902046 ("net: fec: handle page_pool_dev_alloc_pages error"). This is found by our static analysis tool KNighter.Show less

In the Linux kernel, the following vulnerability has been resolved: iommu/mediatek: Fix NULL pointer deference in mtk_iommu_device_group Currently, mtk_iommu calls during probe iommu_device_register before the hw_list from driver data is initialized. Since iommu probing issue fix, it leads to NULL pointer dereference in mtk_iommu_device_group when hw_list is accessed with list_first_entry (not null safe). So, change the call order to ensure iommu_device_register is called after the driver data are initialized.Show less

In the Linux kernel, the following vulnerability has been resolved: soc: samsung: exynos-chipid: Add NULL pointer check in exynos_chipid_probe() soc_dev_attr->revision could be NULL, thus, a pointer check is added to prevent potential NULL pointer dereference. This is similar to the fix in commit 3027e7b15b02 ("ice: Fix some null pointer dereference issues in ice_ptp.c"). This issue is found by our static analysis tool.Show less

In the Linux kernel, the following vulnerability has been resolved: i3c: Add NULL pointer check in i3c_master_queue_ibi() The I3C master driver may receive an IBI from a target device that has not been probed yet. In such cases, the master calls `i3c_master_queue_ibi()` to queue an IBI work task, leading to "Unable to handle kernel read from unreadable memory" and resulting in a kernel panic. Typical IBI handling flow: 1. The I3C master scans target devices and probes their respective drivers. 2. The target device driver calls `i3c_device_request_ibi()` to enable IBI and assigns `dev->ibi = ibi`. 3. The I3C master receives an IBI from the target device and calls `i3c_master_queue_ibi()` to queue the target device driver’s IBI handler task. However, since target device events are asynchronous to the I3C probe sequence, step 3 may occur before step 2, causing `dev->ibi` to be `NULL`, leading to a kernel panic. Add a NULL pointer check in `i3c_master_queue_ibi()` to prevent accessing an uninitialized `dev->ibi`, ensuring stability.Show less

In the Linux kernel, the following vulnerability has been resolved: mfd: ene-kb3930: Fix a potential NULL pointer dereference The off_gpios could be NULL. Add missing check in the kb3930_probe(). This is similar to the issue fixed in commit b1ba8bcb2d1f ("backlight: hx8357: Fix potential NULL pointer dereference"). This was detected by our static analysis tool.Show less

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix NULL pointer in can_accept_new_subflow When testing valkey benchmark tool with MPTCP, the kernel panics in 'mptcp_can_accept_new_subflow' because subflow_req->msk is NULL. Call trace: mptcp_can_accept_new_subflow (./net/mptcp/subflow.c:63 (discriminator 4)) (P) subflow_syn_recv_sock (./net/mptcp/subflow.c:854) tcp_check_req (./net/ipv4/tcp_minisocks.c:863) tcp_v4_rcv (./net/ipv4/tcp_ipv4.c:2268) ip_protocol_deliver_rcu (./net/ipv4/ip_input.c:207) ip_local_deliver_finish (./net/ipv4/ip_input.c:234) ip_local_deliver (./net/ipv4/ip_input.c:254) ip_rcv_finish (./net/ipv4/ip_input.c:449) ... According to the debug log, the same req received two SYN-ACK in a very short time, very likely because the client retransmits the syn ack due to multiple reasons. Even if the packets are transmitted with a relevant time interval, they can be processed by the server on different CPUs concurrently). The 'subflow_req->msk' ownership is transferred to the subflow the first, and there will be a risk of a null pointer dereference here. This patch fixes this issue by moving the 'subflow_req->msk' under the `own_req == true` conditional. Note that the !msk check in subflow_hmac_valid() can be dropped, because the same check already exists under the own_req mpj branch where the code has been moved to.Show less