In the Linux kernel, the following vulnerability has been resolved: leds: an30259a: Use devm_mutex_init() for mutex initialization In this driver LEDs are registered using devm_led_classdev_register() so they are automatically unregistered after module's remove() is done. led_classdev_unregister() calls module's led_set_brightness() to turn off the LEDs and that callback uses mutex which was destroyed already in module's remove() so use devm API instead.

In the Linux kernel, the following vulnerability has been resolved: nvmet: pci-epf: Do not complete commands twice if nvmet_req_init() fails Have nvmet_req_init() and req->execute() complete failed commands. Description of the problem: nvmet_req_init() calls __nvmet_req_complete() internally upon failure, e.g., unsupported opcode, which calls the "queue_response" callback, this results in nvmet_pci_epf_queue_response() being called, which will call nvmet_pci_epf_complete_iod() if data_len is 0 or if dma_dir is different from DMA_TO_DEVICE. This results in a double completion as nvmet_pci_epf_exec_iod_work() also calls nvmet_pci_epf_complete_iod() when nvmet_req_init() fails. Steps to reproduce: On the host send a command with an unsupported opcode with nvme-cli, For example the admin command "security receive" $ sudo nvme security-recv /dev/nvme0n1 -n1 -x4096 This triggers a double completion as nvmet_req_init() fails and nvmet_pci_epf_queue_response() is called, here iod->dma_dir is still in the default state of "DMA_NONE" as set by default in nvmet_pci_epf_alloc_iod(), so nvmet_pci_epf_complete_iod() is called. Because nvmet_req_init() failed nvmet_pci_epf_complete_iod() is also called in nvmet_pci_epf_exec_iod_work() leading to a double completion. This not only sends two completions to the host but also corrupts the state of the PCI NVMe target leading to kernel oops. This patch lets nvmet_req_init() and req->execute() complete all failed commands, and removes the double completion case in nvmet_pci_epf_exec_iod_work() therefore fixing the edge cases where double completions occurred.

In the Linux kernel, the following vulnerability has been resolved: mptcp: ensure snd_una is properly initialized on connect This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt is properly initialized on connect"). It turns out that syzkaller can trigger the retransmit after fallback and before processing any other incoming packet - so that snd_una is still left uninitialized. Address the issue explicitly initializing snd_una together with snd_nxt and write_seq.

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8712: fix uninit-value in r871xu_drv_init() When 'tmpU1b' returns from r8712_read8(padapter, EE_9346CR) is 0, 'mac[6]' will not be initialized. BUG: KMSAN: uninit-value in r871xu_drv_init+0x2d54/0x3070 drivers/staging/rtl8712/usb_intf.c:541 r871xu_drv_init+0x2d54/0x3070 drivers/staging/rtl8712/usb_intf.c:541 usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396 really_probe+0x653/0x14b0 drivers/base/dd.c:596 __driver_probe_device+0x3e9/0x530 drivers/base/dd.c:752 driver_probe_device drivers/base/dd.c:782 [inline] __device_attach_driver+0x79f/0x1120 drivers/base/dd.c:899 bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427 __device_attach+0x593/0x8e0 drivers/base/dd.c:970 device_initial_probe+0x4a/0x60 drivers/base/dd.c:1017 bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487 device_add+0x1fff/0x26e0 drivers/base/core.c:3405 usb_set_configuration+0x37e9/0x3ed0 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0x13c/0x300 drivers/usb/core/generic.c:238 usb_probe_device+0x309/0x570 drivers/usb/core/driver.c:293 really_probe+0x653/0x14b0 drivers/base/dd.c:596 __driver_probe_device+0x3e9/0x530 drivers/base/dd.c:752 driver_probe_device drivers/base/dd.c:782 [inline] __device_attach_driver+0x79f/0x1120 drivers/base/dd.c:899 bus_for_each_drv+0x2d6/0x3f0 drivers/base/bus.c:427 __device_attach+0x593/0x8e0 drivers/base/dd.c:970 device_initial_probe+0x4a/0x60 drivers/base/dd.c:1017 bus_probe_device+0x17b/0x3e0 drivers/base/bus.c:487 device_add+0x1fff/0x26e0 drivers/base/core.c:3405 usb_new_device+0x1b8e/0x2950 drivers/usb/core/hub.c:2566 hub_port_connect drivers/usb/core/hub.c:5358 [inline] hub_port_connect_change drivers/usb/core/hub.c:5502 [inline] port_event drivers/usb/core/hub.c:5660 [inline] hub_event+0x58e3/0x89e0 drivers/usb/core/hub.c:5742 process_one_work+0xdb6/0x1820 kernel/workqueue.c:2307 worker_thread+0x10b3/0x21e0 kernel/workqueue.c:2454 kthread+0x3c7/0x500 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 Local variable mac created at: r871xu_drv_init+0x1771/0x3070 drivers/staging/rtl8712/usb_intf.c:394 usb_probe_interface+0xf19/0x1600 drivers/usb/core/driver.c:396 KMSAN: uninit-value in r871xu_drv_init https://syzkaller.appspot.com/bug?id=3cd92b1d85428b128503bfa7a250294c9ae00bd8

In the Linux kernel, the following vulnerability has been resolved: rtl818x: Prevent using not initialized queues Using not existing queues can panic the kernel with rtl8180/rtl8185 cards. Ignore the skb priority for those cards, they only have one tx queue. Pierre Asselin (pa@panix.com) reported the kernel crash in the Gentoo forum: https://forums.gentoo.org/viewtopic-t-1147832-postdays-0-postorder-asc-start-25.html He also confirmed that this patch fixes the issue. In summary this happened: After updating wpa_supplicant from 2.9 to 2.10 the kernel crashed with a "divide error: 0000" when connecting to an AP. Control port tx now tries to use IEEE80211_AC_VO for the priority, which wpa_supplicants starts to use in 2.10. Since only the rtl8187se part of the driver supports QoS, the priority of the skb is set to IEEE80211_AC_BE (2) by mac80211 for rtl8180/rtl8185 cards. rtl8180 is then unconditionally reading out the priority and finally crashes on drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c line 544 without this patch: idx = (ring->idx + skb_queue_len(&ring->queue)) % ring->entries "ring->entries" is zero for rtl8180/rtl8185 cards, tx_ring[2] never got initialized.

In the Linux kernel, the following vulnerability has been resolved: ipv6: Fix potential uninit-value access in __ip6_make_skb() As it was done in commit fc1092f51567 ("ipv4: Fix uninit-value access in __ip_make_skb()") for IPv4, check FLOWI_FLAG_KNOWN_NH on fl6->flowi6_flags instead of testing HDRINCL on the socket to avoid a race condition which causes uninit-value access.

A NULL pointer dereference flaw was found in the Linux kernel's BPF subsystem in the way a user triggers the map_get_next_key function of the BPF bloom filter. This flaw allows a local user to crash the system. This flaw affects Linux kernel versions prior to 5.17-rc1.

In the Linux kernel, the following vulnerability has been resolved: media: v4l2-core: explicitly clear ioctl input data As seen from a recent syzbot bug report, mistakes in the compat ioctl implementation can lead to uninitialized kernel stack data getting used as input for driver ioctl handlers. The reported bug is now fixed, but it's possible that other related bugs are still present or get added in the future. As the drivers need to check user input already, the possible impact is fairly low, but it might still cause an information leak. To be on the safe side, always clear the entire ioctl buffer before calling the conversion handler functions that are meant to initialize them.

In the Linux kernel, the following vulnerability has been resolved: net: hns3: put off calling register_netdev() until client initialize complete Currently, the netdevice is registered before client initializing complete. So there is a timewindow between netdevice available and usable. In this case, if user try to change the channel number or ring param, it may cause the hns3_set_rx_cpu_rmap() being called twice, and report bug. [47199.416502] hns3 0000:35:00.0 eth1: set channels: tqp_num=1, rxfh=0 [47199.430340] hns3 0000:35:00.0 eth1: already uninitialized [47199.438554] hns3 0000:35:00.0: rss changes from 4 to 1 [47199.511854] hns3 0000:35:00.0: Channels changed, rss_size from 4 to 1, tqps from 4 to 1 [47200.163524] ------------[ cut here ]------------ [47200.171674] kernel BUG at lib/cpu_rmap.c:142! [47200.177847] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [47200.185259] Modules linked in: hclge(+) hns3(-) hns3_cae(O) hns_roce_hw_v2 hnae3 vfio_iommu_type1 vfio_pci vfio_virqfd vfio pv680_mii(O) [last unloaded: hclge] [47200.205912] CPU: 1 PID: 8260 Comm: ethtool Tainted: G O 5.11.0-rc3+ #1 [47200.215601] Hardware name: , xxxxxx 02/04/2021 [47200.223052] pstate: 60400009 (nZCv daif +PAN -UAO -TCO BTYPE=--) [47200.230188] pc : cpu_rmap_add+0x38/0x40 [47200.237472] lr : irq_cpu_rmap_add+0x84/0x140 [47200.243291] sp : ffff800010e93a30 [47200.247295] x29: ffff800010e93a30 x28: ffff082100584880 [47200.254155] x27: 0000000000000000 x26: 0000000000000000 [47200.260712] x25: 0000000000000000 x24: 0000000000000004 [47200.267241] x23: ffff08209ba03000 x22: ffff08209ba038c0 [47200.273789] x21: 000000000000003f x20: ffff0820e2bc1680 [47200.280400] x19: ffff0820c970ec80 x18: 00000000000000c0 [47200.286944] x17: 0000000000000000 x16: ffffb43debe4a0d0 [47200.293456] x15: fffffc2082990600 x14: dead000000000122 [47200.300059] x13: ffffffffffffffff x12: 000000000000003e [47200.306606] x11: ffff0820815b8080 x10: ffff53e411988000 [47200.313171] x9 : 0000000000000000 x8 : ffff0820e2bc1700 [47200.319682] x7 : 0000000000000000 x6 : 000000000000003f [47200.326170] x5 : 0000000000000040 x4 : ffff800010e93a20 [47200.332656] x3 : 0000000000000004 x2 : ffff0820c970ec80 [47200.339168] x1 : ffff0820e2bc1680 x0 : 0000000000000004 [47200.346058] Call trace: [47200.349324] cpu_rmap_add+0x38/0x40 [47200.354300] hns3_set_rx_cpu_rmap+0x6c/0xe0 [hns3] [47200.362294] hns3_reset_notify_init_enet+0x1cc/0x340 [hns3] [47200.370049] hns3_change_channels+0x40/0xb0 [hns3] [47200.376770] hns3_set_channels+0x12c/0x2a0 [hns3] [47200.383353] ethtool_set_channels+0x140/0x250 [47200.389772] dev_ethtool+0x714/0x23d0 [47200.394440] dev_ioctl+0x4cc/0x640 [47200.399277] sock_do_ioctl+0x100/0x2a0 [47200.404574] sock_ioctl+0x28c/0x470 [47200.409079] __arm64_sys_ioctl+0xb4/0x100 [47200.415217] el0_svc_common.constprop.0+0x84/0x210 [47200.422088] do_el0_svc+0x28/0x34 [47200.426387] el0_svc+0x28/0x70 [47200.431308] el0_sync_handler+0x1a4/0x1b0 [47200.436477] el0_sync+0x174/0x180 [47200.441562] Code: 11000405 79000c45 f8247861 d65f03c0 (d4210000) [47200.448869] ---[ end trace a01efe4ce42e5f34 ]--- The process is like below: excuting hns3_client_init | register_netdev() | hns3_set_channels() | | hns3_set_rx_cpu_rmap() hns3_reset_notify_uninit_enet() | | | quit without calling function | hns3_free_rx_cpu_rmap for flag | HNS3_NIC_STATE_INITED is unset. | | | hns3_reset_notify_init_enet() | | set HNS3_NIC_STATE_INITED call hns3_set_rx_cpu_rmap()-- crash Fix it by calling register_netdev() at the end of function hns3_client_init().

In the Linux kernel, the following vulnerability has been resolved: mm/mempolicy: do not allow illegal MPOL_F_NUMA_BALANCING | MPOL_LOCAL in mbind() syzbot reported access to unitialized memory in mbind() [1] Issue came with commit bda420b98505 ("numa balancing: migrate on fault among multiple bound nodes") This commit added a new bit in MPOL_MODE_FLAGS, but only checked valid combination (MPOL_F_NUMA_BALANCING can only be used with MPOL_BIND) in do_set_mempolicy() This patch moves the check in sanitize_mpol_flags() so that it is also used by mbind() [1] BUG: KMSAN: uninit-value in __mpol_equal+0x567/0x590 mm/mempolicy.c:2260 __mpol_equal+0x567/0x590 mm/mempolicy.c:2260 mpol_equal include/linux/mempolicy.h:105 [inline] vma_merge+0x4a1/0x1e60 mm/mmap.c:1190 mbind_range+0xcc8/0x1e80 mm/mempolicy.c:811 do_mbind+0xf42/0x15f0 mm/mempolicy.c:1333 kernel_mbind mm/mempolicy.c:1483 [inline] __do_sys_mbind mm/mempolicy.c:1490 [inline] __se_sys_mbind+0x437/0xb80 mm/mempolicy.c:1486 __x64_sys_mbind+0x19d/0x200 mm/mempolicy.c:1486 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_alloc_node mm/slub.c:3221 [inline] slab_alloc mm/slub.c:3230 [inline] kmem_cache_alloc+0x751/0xff0 mm/slub.c:3235 mpol_new mm/mempolicy.c:293 [inline] do_mbind+0x912/0x15f0 mm/mempolicy.c:1289 kernel_mbind mm/mempolicy.c:1483 [inline] __do_sys_mbind mm/mempolicy.c:1490 [inline] __se_sys_mbind+0x437/0xb80 mm/mempolicy.c:1486 __x64_sys_mbind+0x19d/0x200 mm/mempolicy.c:1486 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae ===================================================== Kernel panic - not syncing: panic_on_kmsan set ... CPU: 0 PID: 15049 Comm: syz-executor.0 Tainted: G B 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1ff/0x28e lib/dump_stack.c:106 dump_stack+0x25/0x28 lib/dump_stack.c:113 panic+0x44f/0xdeb kernel/panic.c:232 kmsan_report+0x2ee/0x300 mm/kmsan/report.c:186 __msan_warning+0xd7/0x150 mm/kmsan/instrumentation.c:208 __mpol_equal+0x567/0x590 mm/mempolicy.c:2260 mpol_equal include/linux/mempolicy.h:105 [inline] vma_merge+0x4a1/0x1e60 mm/mmap.c:1190 mbind_range+0xcc8/0x1e80 mm/mempolicy.c:811 do_mbind+0xf42/0x15f0 mm/mempolicy.c:1333 kernel_mbind mm/mempolicy.c:1483 [inline] __do_sys_mbind mm/mempolicy.c:1490 [inline] __se_sys_mbind+0x437/0xb80 mm/mempolicy.c:1486 __x64_sys_mbind+0x19d/0x200 mm/mempolicy.c:1486 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbage value Currently, when the rule related to IDLETIMER is added, idletimer_tg timer structure is initialized by kmalloc on executing idletimer_tg_create function. However, in this process timer->timer_type is not defined to a specific value. Thus, timer->timer_type has garbage value and it occurs kernel panic. So, this commit fixes the panic by initializing timer->timer_type using kzalloc instead of kmalloc. Test commands: # iptables -A OUTPUT -j IDLETIMER --timeout 1 --label test $ cat /sys/class/xt_idletimer/timers/test Killed Splat looks like: BUG: KASAN: user-memory-access in alarm_expires_remaining+0x49/0x70 Read of size 8 at addr 0000002e8c7bc4c8 by task cat/917 CPU: 12 PID: 917 Comm: cat Not tainted 5.14.0+ #3 79940a339f71eb14fc81aee1757a20d5bf13eb0e Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: dump_stack_lvl+0x6e/0x9c kasan_report.cold+0x112/0x117 ? alarm_expires_remaining+0x49/0x70 __asan_load8+0x86/0xb0 alarm_expires_remaining+0x49/0x70 idletimer_tg_show+0xe5/0x19b [xt_IDLETIMER 11219304af9316a21bee5ba9d58f76a6b9bccc6d] dev_attr_show+0x3c/0x60 sysfs_kf_seq_show+0x11d/0x1f0 ? device_remove_bin_file+0x20/0x20 kernfs_seq_show+0xa4/0xb0 seq_read_iter+0x29c/0x750 kernfs_fop_read_iter+0x25a/0x2c0 ? __fsnotify_parent+0x3d1/0x570 ? iov_iter_init+0x70/0x90 new_sync_read+0x2a7/0x3d0 ? __x64_sys_llseek+0x230/0x230 ? rw_verify_area+0x81/0x150 vfs_read+0x17b/0x240 ksys_read+0xd9/0x180 ? vfs_write+0x460/0x460 ? do_syscall_64+0x16/0xc0 ? lockdep_hardirqs_on+0x79/0x120 __x64_sys_read+0x43/0x50 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0cdc819142 Code: c0 e9 c2 fe ff ff 50 48 8d 3d 3a ca 0a 00 e8 f5 19 02 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24 RSP: 002b:00007fff28eee5b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f0cdc819142 RDX: 0000000000020000 RSI: 00007f0cdc032000 RDI: 0000000000000003 RBP: 00007f0cdc032000 R08: 00007f0cdc031010 R09: 0000000000000000 R10: 0000000000000022 R11: 0000000000000246 R12: 00005607e9ee31f0 R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000

In the Linux kernel, the following vulnerability has been resolved: media: mxl111sf: change mutex_init() location Syzbot reported, that mxl111sf_ctrl_msg() uses uninitialized mutex. The problem was in wrong mutex_init() location. Previous mutex_init(&state->msg_lock) call was in ->init() function, but dvb_usbv2_init() has this order of calls: dvb_usbv2_init() dvb_usbv2_adapter_init() dvb_usbv2_adapter_frontend_init() props->frontend_attach() props->init() Since mxl111sf_* devices call mxl111sf_ctrl_msg() in ->frontend_attach() internally we need to initialize state->msg_lock before frontend_attach(). To achieve it, ->probe() call added to all mxl111sf_* devices, which will simply initiaize mutex.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/a4xx: fix error handling in a4xx_gpu_init() This code returns 1 on error instead of a negative error. It leads to an Oops in the caller. A second problem is that the check for "if (ret != -ENODATA)" cannot be true because "ret" is set to 1.

In the Linux kernel, the following vulnerability has been resolved: vdpa_sim: avoid putting an uninitialized iova_domain The system will crash if we put an uninitialized iova_domain, this could happen when an error occurs before initializing the iova_domain in vdpasim_create(). BUG: kernel NULL pointer dereference, address: 0000000000000000 ... RIP: 0010:__cpuhp_state_remove_instance+0x96/0x1c0 ... Call Trace: <TASK> put_iova_domain+0x29/0x220 vdpasim_free+0xd1/0x120 [vdpa_sim] vdpa_release_dev+0x21/0x40 [vdpa] device_release+0x33/0x90 kobject_release+0x63/0x160 vdpasim_create+0x127/0x2a0 [vdpa_sim] vdpasim_net_dev_add+0x7d/0xfe [vdpa_sim_net] vdpa_nl_cmd_dev_add_set_doit+0xe1/0x1a0 [vdpa] genl_family_rcv_msg_doit+0x112/0x140 genl_rcv_msg+0xdf/0x1d0 ... So we must make sure the iova_domain is already initialized before put it. In addition, we may get the following warning in this case: WARNING: ... drivers/iommu/iova.c:344 iova_cache_put+0x58/0x70 So we must make sure the iova_cache_put() is invoked only if the iova_cache_get() is already invoked. Let's fix it together.

In the Linux kernel, the following vulnerability has been resolved: do_sys_name_to_handle(): use kzalloc() to fix kernel-infoleak syzbot identified a kernel information leak vulnerability in do_sys_name_to_handle() and issued the following report [1]. [1] "BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_user+0xbc/0x100 lib/usercopy.c:40 instrument_copy_to_user include/linux/instrumented.h:114 [inline] _copy_to_user+0xbc/0x100 lib/usercopy.c:40 copy_to_user include/linux/uaccess.h:191 [inline] do_sys_name_to_handle fs/fhandle.c:73 [inline] __do_sys_name_to_handle_at fs/fhandle.c:112 [inline] __se_sys_name_to_handle_at+0x949/0xb10 fs/fhandle.c:94 __x64_sys_name_to_handle_at+0xe4/0x140 fs/fhandle.c:94 ... Uninit was created at: slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768 slab_alloc_node mm/slub.c:3478 [inline] __kmem_cache_alloc_node+0x5c9/0x970 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0x121/0x3c0 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] do_sys_name_to_handle fs/fhandle.c:39 [inline] __do_sys_name_to_handle_at fs/fhandle.c:112 [inline] __se_sys_name_to_handle_at+0x441/0xb10 fs/fhandle.c:94 __x64_sys_name_to_handle_at+0xe4/0x140 fs/fhandle.c:94 ... Bytes 18-19 of 20 are uninitialized Memory access of size 20 starts at ffff888128a46380 Data copied to user address 0000000020000240" Per Chuck Lever's suggestion, use kzalloc() instead of kmalloc() to solve the problem.

In the Linux kernel, the following vulnerability has been resolved: arm64: kexec: initialize kexec_buf struct in load_other_segments() Patch series "kexec: Fix invalid field access". The kexec_buf structure was previously declared without initialization. commit bf454ec31add ("kexec_file: allow to place kexec_buf randomly") added a field that is always read but not consistently populated by all architectures. This un-initialized field will contain garbage. This is also triggering a UBSAN warning when the uninitialized data was accessed: ------------[ cut here ]------------ UBSAN: invalid-load in ./include/linux/kexec.h:210:10 load of value 252 is not a valid value for type '_Bool' Zero-initializing kexec_buf at declaration ensures all fields are cleanly set, preventing future instances of uninitialized memory being used. An initial fix was already landed for arm64[0], and this patchset fixes the problem on the remaining arm64 code and on riscv, as raised by Mark. Discussions about this problem could be found at[1][2]. This patch (of 3): The kexec_buf structure was previously declared without initialization. commit bf454ec31add ("kexec_file: allow to place kexec_buf randomly") added a field that is always read but not consistently populated by all architectures. This un-initialized field will contain garbage. This is also triggering a UBSAN warning when the uninitialized data was accessed: ------------[ cut here ]------------ UBSAN: invalid-load in ./include/linux/kexec.h:210:10 load of value 252 is not a valid value for type '_Bool' Zero-initializing kexec_buf at declaration ensures all fields are cleanly set, preventing future instances of uninitialized memory being used.

In the Linux kernel, the following vulnerability has been resolved: erspan: make sure erspan_base_hdr is present in skb->head syzbot reported a problem in ip6erspan_rcv() [1] Issue is that ip6erspan_rcv() (and erspan_rcv()) no longer make sure erspan_base_hdr is present in skb linear part (skb->head) before getting @ver field from it. Add the missing pskb_may_pull() calls. v2: Reload iph pointer in erspan_rcv() after pskb_may_pull() because skb->head might have changed. [1] BUG: KMSAN: uninit-value in pskb_may_pull_reason include/linux/skbuff.h:2742 [inline] BUG: KMSAN: uninit-value in pskb_may_pull include/linux/skbuff.h:2756 [inline] BUG: KMSAN: uninit-value in ip6erspan_rcv net/ipv6/ip6_gre.c:541 [inline] BUG: KMSAN: uninit-value in gre_rcv+0x11f8/0x1930 net/ipv6/ip6_gre.c:610 pskb_may_pull_reason include/linux/skbuff.h:2742 [inline] pskb_may_pull include/linux/skbuff.h:2756 [inline] ip6erspan_rcv net/ipv6/ip6_gre.c:541 [inline] gre_rcv+0x11f8/0x1930 net/ipv6/ip6_gre.c:610 ip6_protocol_deliver_rcu+0x1d4c/0x2ca0 net/ipv6/ip6_input.c:438 ip6_input_finish net/ipv6/ip6_input.c:483 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ip6_input+0x15d/0x430 net/ipv6/ip6_input.c:492 ip6_mc_input+0xa7e/0xc80 net/ipv6/ip6_input.c:586 dst_input include/net/dst.h:460 [inline] ip6_rcv_finish+0x955/0x970 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:314 [inline] ipv6_rcv+0xde/0x390 net/ipv6/ip6_input.c:310 __netif_receive_skb_one_core net/core/dev.c:5538 [inline] __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5652 netif_receive_skb_internal net/core/dev.c:5738 [inline] netif_receive_skb+0x58/0x660 net/core/dev.c:5798 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1549 tun_get_user+0x5566/0x69e0 drivers/net/tun.c:2002 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048 call_write_iter include/linux/fs.h:2108 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xb63/0x1520 fs/read_write.c:590 ksys_write+0x20f/0x4c0 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0x93/0xe0 fs/read_write.c:652 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Uninit was created at: slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1318 [inline] alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795 tun_alloc_skb drivers/net/tun.c:1525 [inline] tun_get_user+0x209a/0x69e0 drivers/net/tun.c:1846 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048 call_write_iter include/linux/fs.h:2108 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xb63/0x1520 fs/read_write.c:590 ksys_write+0x20f/0x4c0 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0x93/0xe0 fs/read_write.c:652 do_syscall_64+0xd5/0x1f0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 CPU: 1 PID: 5045 Comm: syz-executor114 Not tainted 6.9.0-rc1-syzkaller-00021-g962490525cff #0

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reject TDLS operations when station is not associated syzbot triggered a WARN in ieee80211_tdls_oper() by sending NL80211_TDLS_ENABLE_LINK immediately after NL80211_CMD_CONNECT, before association completed and without prior TDLS setup. This left internal state like sdata->u.mgd.tdls_peer uninitialized, leading to a WARN_ON() in code paths that assumed it was valid. Reject the operation early if not in station mode or not associated.

In the Linux kernel, the following vulnerability has been resolved: sched_ext: bpf_iter_scx_dsq_new() should always initialize iterator BPF programs may call next() and destroy() on BPF iterators even after new() returns an error value (e.g. bpf_for_each() macro ignores error returns from new()). bpf_iter_scx_dsq_new() could leave the iterator in an uninitialized state after an error return causing bpf_iter_scx_dsq_next() to dereference garbage data. Make bpf_iter_scx_dsq_new() always clear $kit->dsq so that next() and destroy() become noops.

In the Linux kernel, the following vulnerability has been resolved: net: sched: cls_api: fix tc_chain_fill_node to initialize tcm_info to zero to prevent an info-leak When building netlink messages, tc_chain_fill_node() never initializes the tcm_info field of struct tcmsg. Since the allocation is not zeroed, kernel heap memory is leaked to userspace through this 4-byte field. The fix simply zeroes tcm_info alongside the other fields that are already initialized.

In the Linux kernel, the following vulnerability has been resolved: of/fdt: run soc memory setup when early_init_dt_scan_memory fails If memory has been found early_init_dt_scan_memory now returns 1. If it hasn't found any memory it will return 0, allowing other memory setup mechanisms to carry on. Previously early_init_dt_scan_memory always returned 0 without distinguishing between any kind of memory setup being done or not. Any code path after the early_init_dt_scan memory call in the ramips plat_mem_setup code wouldn't be executed anymore. Making early_init_dt_scan_memory the only way to initialize the memory. Some boards, including my mt7621 based Cudy X6 board, depend on memory initialization being done via the soc_info.mem_detect function pointer. Those wouldn't be able to obtain memory and panic the kernel during early bootup with the message "early_init_dt_alloc_memory_arch: Failed to allocate 12416 bytes align=0x40".

In the Linux kernel, the following vulnerability has been resolved: drm/sched: Check scheduler work queue before calling timeout handling During an IGT GPU reset test we see again oops despite of commit 0c8c901aaaebc9 (drm/sched: Check scheduler ready before calling timeout handling). It uses ready condition whether to call drm_sched_fault which unwind the TDR leads to GPU reset. However it looks the ready condition is overloaded with other meanings, for example, for the following stack is related GPU reset : 0 gfx_v9_0_cp_gfx_start 1 gfx_v9_0_cp_gfx_resume 2 gfx_v9_0_cp_resume 3 gfx_v9_0_hw_init 4 gfx_v9_0_resume 5 amdgpu_device_ip_resume_phase2 does the following: /* start the ring */ gfx_v9_0_cp_gfx_start(adev); ring->sched.ready = true; The same approach is for other ASICs as well : gfx_v8_0_cp_gfx_resume gfx_v10_0_kiq_resume, etc... As a result, our GPU reset test causes GPU fault which calls unconditionally gfx_v9_0_fault and then drm_sched_fault. However now it depends on whether the interrupt service routine drm_sched_fault is executed after gfx_v9_0_cp_gfx_start is completed which sets the ready field of the scheduler to true even for uninitialized schedulers and causes oops vs no fault or when ISR drm_sched_fault is completed prior gfx_v9_0_cp_gfx_start and NULL pointer dereference does not occur. Use the field timeout_wq to prevent oops for uninitialized schedulers. The field could be initialized by the work queue of resetting the domain. v1: Corrections to commit message (Luben)

In the Linux kernel, the following vulnerability has been resolved: udf: Fix uninitialized array access for some pathnames For filenames that begin with . and are between 2 and 5 characters long, UDF charset conversion code would read uninitialized memory in the output buffer. The only practical impact is that the name may be prepended a "unification hash" when it is not actually needed but still it is good to fix this.

In the Linux kernel, the following vulnerability has been resolved: hsr: Fix uninit-value access in fill_frame_info() Syzbot reports the following uninit-value access problem. ===================================================== BUG: KMSAN: uninit-value in fill_frame_info net/hsr/hsr_forward.c:601 [inline] BUG: KMSAN: uninit-value in hsr_forward_skb+0x9bd/0x30f0 net/hsr/hsr_forward.c:616 fill_frame_info net/hsr/hsr_forward.c:601 [inline] hsr_forward_skb+0x9bd/0x30f0 net/hsr/hsr_forward.c:616 hsr_dev_xmit+0x192/0x330 net/hsr/hsr_device.c:223 __netdev_start_xmit include/linux/netdevice.h:4889 [inline] netdev_start_xmit include/linux/netdevice.h:4903 [inline] xmit_one net/core/dev.c:3544 [inline] dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3560 __dev_queue_xmit+0x34d0/0x52a0 net/core/dev.c:4340 dev_queue_xmit include/linux/netdevice.h:3082 [inline] packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3087 [inline] packet_sendmsg+0x8b1d/0x9f30 net/packet/af_packet.c:3119 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] __sys_sendto+0x781/0xa30 net/socket.c:2176 __do_sys_sendto net/socket.c:2188 [inline] __se_sys_sendto net/socket.c:2184 [inline] __ia32_sys_sendto+0x11f/0x1c0 net/socket.c:2184 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Uninit was created at: slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767 slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:559 __alloc_skb+0x318/0x740 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6299 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2794 packet_alloc_skb net/packet/af_packet.c:2936 [inline] packet_snd net/packet/af_packet.c:3030 [inline] packet_sendmsg+0x70e8/0x9f30 net/packet/af_packet.c:3119 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg net/socket.c:753 [inline] __sys_sendto+0x781/0xa30 net/socket.c:2176 __do_sys_sendto net/socket.c:2188 [inline] __se_sys_sendto net/socket.c:2184 [inline] __ia32_sys_sendto+0x11f/0x1c0 net/socket.c:2184 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246 entry_SYSENTER_compat_after_hwframe+0x70/0x82 It is because VLAN not yet supported in hsr driver. Return error when protocol is ETH_P_8021Q in fill_frame_info() now to fix it.

In the Linux kernel, the following vulnerability has been resolved: wifi: ath11k: fix deinitialization of firmware resources Currently, in ath11k_ahb_fw_resources_init(), iommu domain mapping is done only for the chipsets having fixed firmware memory. Also, for such chipsets, mapping is done only if it does not have TrustZone support. During deinitialization, only if TrustZone support is not there, iommu is unmapped back. However, for non fixed firmware memory chipsets, TrustZone support is not there and this makes the condition check to true and it tries to unmap the memory which was not mapped during initialization. This leads to the following trace - [ 83.198790] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 [ 83.259537] Modules linked in: ath11k_ahb ath11k qmi_helpers .. snip .. [ 83.280286] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 83.287228] pc : __iommu_unmap+0x30/0x140 [ 83.293907] lr : iommu_unmap+0x5c/0xa4 [ 83.298072] sp : ffff80000b3abad0 .. snip .. [ 83.369175] Call trace: [ 83.376282] __iommu_unmap+0x30/0x140 [ 83.378541] iommu_unmap+0x5c/0xa4 [ 83.382360] ath11k_ahb_fw_resource_deinit.part.12+0x2c/0xac [ath11k_ahb] [ 83.385666] ath11k_ahb_free_resources+0x140/0x17c [ath11k_ahb] [ 83.392521] ath11k_ahb_shutdown+0x34/0x40 [ath11k_ahb] [ 83.398248] platform_shutdown+0x20/0x2c [ 83.403455] device_shutdown+0x16c/0x1c4 [ 83.407621] kernel_restart_prepare+0x34/0x3c [ 83.411529] kernel_restart+0x14/0x74 [ 83.415781] __do_sys_reboot+0x1c4/0x22c [ 83.419427] __arm64_sys_reboot+0x1c/0x24 [ 83.423420] invoke_syscall+0x44/0xfc [ 83.427326] el0_svc_common.constprop.3+0xac/0xe8 [ 83.430974] do_el0_svc+0xa0/0xa8 [ 83.435659] el0_svc+0x1c/0x44 [ 83.438957] el0t_64_sync_handler+0x60/0x144 [ 83.441910] el0t_64_sync+0x15c/0x160 [ 83.446343] Code: aa0103f4 f9400001 f90027a1 d2800001 (f94006a0) [ 83.449903] ---[ end trace 0000000000000000 ]--- This can be reproduced by probing an AHB chipset which is not having a fixed memory region. During reboot (or rmmod) trace can be seen. Fix this issue by adding a condition check on firmware fixed memory hw_param as done in the counter initialization function. Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1

In the Linux kernel, the following vulnerability has been resolved: RDMA/cma: Allow UD qp_type to join multicast only As for multicast: - The SIDR is the only mode that makes sense; - Besides PS_UDP, other port spaces like PS_IB is also allowed, as it is UD compatible. In this case qkey also needs to be set [1]. This patch allows only UD qp_type to join multicast, and set qkey to default if it's not set, to fix an uninit-value error: the ib->rec.qkey field is accessed without being initialized. ===================================================== BUG: KMSAN: uninit-value in cma_set_qkey drivers/infiniband/core/cma.c:510 [inline] BUG: KMSAN: uninit-value in cma_make_mc_event+0xb73/0xe00 drivers/infiniband/core/cma.c:4570 cma_set_qkey drivers/infiniband/core/cma.c:510 [inline] cma_make_mc_event+0xb73/0xe00 drivers/infiniband/core/cma.c:4570 cma_iboe_join_multicast drivers/infiniband/core/cma.c:4782 [inline] rdma_join_multicast+0x2b83/0x30a0 drivers/infiniband/core/cma.c:4814 ucma_process_join+0xa76/0xf60 drivers/infiniband/core/ucma.c:1479 ucma_join_multicast+0x1e3/0x250 drivers/infiniband/core/ucma.c:1546 ucma_write+0x639/0x6d0 drivers/infiniband/core/ucma.c:1732 vfs_write+0x8ce/0x2030 fs/read_write.c:588 ksys_write+0x28c/0x520 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __ia32_sys_write+0xdb/0x120 fs/read_write.c:652 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline] __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c Local variable ib.i created at: cma_iboe_join_multicast drivers/infiniband/core/cma.c:4737 [inline] rdma_join_multicast+0x586/0x30a0 drivers/infiniband/core/cma.c:4814 ucma_process_join+0xa76/0xf60 drivers/infiniband/core/ucma.c:1479 CPU: 0 PID: 29874 Comm: syz-executor.3 Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ===================================================== [1] https://lore.kernel.org/linux-rdma/20220117183832.GD84788@nvidia.com/

In the Linux kernel, the following vulnerability has been resolved: cxl/region: Do not try to cleanup after cxl_region_setup_targets() fails Commit 5e42bcbc3fef ("cxl/region: decrement ->nr_targets on error in cxl_region_attach()") tried to avoid 'eiw' initialization errors when ->nr_targets exceeded 16, by just decrementing ->nr_targets when cxl_region_setup_targets() failed. Commit 86987c766276 ("cxl/region: Cleanup target list on attach error") extended that cleanup to also clear cxled->pos and p->targets[pos]. The initialization error was incidentally fixed separately by: Commit 8d4285425714 ("cxl/region: Fix port setup uninitialized variable warnings") which was merged a few days after 5e42bcbc3fef. But now the original cleanup when cxl_region_setup_targets() fails prevents endpoint and switch decoder resources from being reused: 1) the cleanup does not set the decoder's region to NULL, which results in future dpa_size_store() calls returning -EBUSY 2) the decoder is not properly freed, which results in future commit errors associated with the upstream switch Now that the initialization errors were fixed separately, the proper cleanup for this case is to just return immediately. Then the resources associated with this target get cleanup up as normal when the failed region is deleted. The ->nr_targets decrement in the error case also helped prevent a p->targets[] array overflow, so add a new check to prevent against that overflow. Tested by trying to create an invalid region for a 2 switch * 2 endpoint topology, and then following up with creating a valid region.

In the Linux kernel, the following vulnerability has been resolved: llc: verify mac len before reading mac header LLC reads the mac header with eth_hdr without verifying that the skb has an Ethernet header. Syzbot was able to enter llc_rcv on a tun device. Tun can insert packets without mac len and with user configurable skb->protocol (passing a tun_pi header when not configuring IFF_NO_PI). BUG: KMSAN: uninit-value in llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline] BUG: KMSAN: uninit-value in llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111 llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline] llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111 llc_rcv+0xc5d/0x14a0 net/llc/llc_input.c:218 __netif_receive_skb_one_core net/core/dev.c:5523 [inline] __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5637 netif_receive_skb_internal net/core/dev.c:5723 [inline] netif_receive_skb+0x58/0x660 net/core/dev.c:5782 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555 tun_get_user+0x54c5/0x69c0 drivers/net/tun.c:2002 Add a mac_len test before all three eth_hdr(skb) calls under net/llc. There are further uses in include/net/llc_pdu.h. All these are protected by a test skb->protocol == ETH_P_802_2. Which does not protect against this tun scenario. But the mac_len test added in this patch in llc_fixup_skb will indirectly protect those too. That is called from llc_rcv before any other LLC code. It is tempting to just add a blanket mac_len check in llc_rcv, but not sure whether that could break valid LLC paths that do not assume an Ethernet header. 802.2 LLC may be used on top of non-802.3 protocols in principle. The below referenced commit shows that used to, on top of Token Ring. At least one of the three eth_hdr uses goes back to before the start of git history. But the one that syzbot exercises is introduced in this commit. That commit is old enough (2008), that effectively all stable kernels should receive this.

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: Initialize ctx to avoid memory allocation error It is possible that ctx in nfqnl_build_packet_message() could be used before it is properly initialize, which is only initialized by nfqnl_get_sk_secctx(). This patch corrects this problem by initializing the lsmctx to a safe value when it is declared. This is similar to the commit 35fcac7a7c25 ("audit: Initialize lsmctx to avoid memory allocation error").

In the Linux kernel, the following vulnerability has been resolved: can: j1939: j1939_send_one(): fix missing CAN header initialization The read access to struct canxl_frame::len inside of a j1939 created skbuff revealed a missing initialization of reserved and later filled elements in struct can_frame. This patch initializes the 8 byte CAN header with zero.

In the Linux kernel, the following vulnerability has been resolved: wifi: wil6210: debugfs: fix uninitialized variable use in `wil_write_file_wmi()` Commit 7a4836560a61 changes simple_write_to_buffer() with memdup_user() but it forgets to change the value to be returned that came from simple_write_to_buffer() call. It results in the following warning: warning: variable 'rc' is uninitialized when used here [-Wuninitialized] return rc; ^~ Remove rc variable and just return the passed in length if the memdup_user() succeeds.

In the Linux kernel, the following vulnerability has been resolved: mm/mempolicy: fix uninit-value in mpol_rebind_policy() mpol_set_nodemask()(mm/mempolicy.c) does not set up nodemask when pol->mode is MPOL_LOCAL. Check pol->mode before access pol->w.cpuset_mems_allowed in mpol_rebind_policy()(mm/mempolicy.c). BUG: KMSAN: uninit-value in mpol_rebind_policy mm/mempolicy.c:352 [inline] BUG: KMSAN: uninit-value in mpol_rebind_task+0x2ac/0x2c0 mm/mempolicy.c:368 mpol_rebind_policy mm/mempolicy.c:352 [inline] mpol_rebind_task+0x2ac/0x2c0 mm/mempolicy.c:368 cpuset_change_task_nodemask kernel/cgroup/cpuset.c:1711 [inline] cpuset_attach+0x787/0x15e0 kernel/cgroup/cpuset.c:2278 cgroup_migrate_execute+0x1023/0x1d20 kernel/cgroup/cgroup.c:2515 cgroup_migrate kernel/cgroup/cgroup.c:2771 [inline] cgroup_attach_task+0x540/0x8b0 kernel/cgroup/cgroup.c:2804 __cgroup1_procs_write+0x5cc/0x7a0 kernel/cgroup/cgroup-v1.c:520 cgroup1_tasks_write+0x94/0xb0 kernel/cgroup/cgroup-v1.c:539 cgroup_file_write+0x4c2/0x9e0 kernel/cgroup/cgroup.c:3852 kernfs_fop_write_iter+0x66a/0x9f0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2162 [inline] new_sync_write fs/read_write.c:503 [inline] vfs_write+0x1318/0x2030 fs/read_write.c:590 ksys_write+0x28b/0x510 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0xdb/0x120 fs/read_write.c:652 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:3251 [inline] slab_alloc mm/slub.c:3259 [inline] kmem_cache_alloc+0x902/0x11c0 mm/slub.c:3264 mpol_new mm/mempolicy.c:293 [inline] do_set_mempolicy+0x421/0xb70 mm/mempolicy.c:853 kernel_set_mempolicy mm/mempolicy.c:1504 [inline] __do_sys_set_mempolicy mm/mempolicy.c:1510 [inline] __se_sys_set_mempolicy+0x44c/0xb60 mm/mempolicy.c:1507 __x64_sys_set_mempolicy+0xd8/0x110 mm/mempolicy.c:1507 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae KMSAN: uninit-value in mpol_rebind_task (2) https://syzkaller.appspot.com/bug?id=d6eb90f952c2a5de9ea718a1b873c55cb13b59dc This patch seems to fix below bug too. KMSAN: uninit-value in mpol_rebind_mm (2) https://syzkaller.appspot.com/bug?id=f2fecd0d7013f54ec4162f60743a2b28df40926b The uninit-value is pol->w.cpuset_mems_allowed in mpol_rebind_policy(). When syzkaller reproducer runs to the beginning of mpol_new(), mpol_new() mm/mempolicy.c do_mbind() mm/mempolicy.c kernel_mbind() mm/mempolicy.c `mode` is 1(MPOL_PREFERRED), nodes_empty(*nodes) is `true` and `flags` is 0. Then mode = MPOL_LOCAL; ... policy->mode = mode; policy->flags = flags; will be executed. So in mpol_set_nodemask(), mpol_set_nodemask() mm/mempolicy.c do_mbind() kernel_mbind() pol->mode is 4 (MPOL_LOCAL), that `nodemask` in `pol` is not initialized, which will be accessed in mpol_rebind_policy().

In the Linux kernel, the following vulnerability has been resolved: ext4: init quota for 'old.inode' in 'ext4_rename' Syzbot found the following issue: ext4_parse_param: s_want_extra_isize=128 ext4_inode_info_init: s_want_extra_isize=32 ext4_rename: old.inode=ffff88823869a2c8 old.dir=ffff888238699828 new.inode=ffff88823869d7e8 new.dir=ffff888238699828 __ext4_mark_inode_dirty: inode=ffff888238699828 ea_isize=32 want_ea_size=128 __ext4_mark_inode_dirty: inode=ffff88823869a2c8 ea_isize=32 want_ea_size=128 ext4_xattr_block_set: inode=ffff88823869a2c8 ------------[ cut here ]------------ WARNING: CPU: 13 PID: 2234 at fs/ext4/xattr.c:2070 ext4_xattr_block_set.cold+0x22/0x980 Modules linked in: RIP: 0010:ext4_xattr_block_set.cold+0x22/0x980 RSP: 0018:ffff888227d3f3b0 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88823007a000 RCX: 0000000000000000 RDX: 0000000000000a03 RSI: 0000000000000040 RDI: ffff888230078178 RBP: 0000000000000000 R08: 000000000000002c R09: ffffed1075c7df8e R10: ffff8883ae3efc6b R11: ffffed1075c7df8d R12: 0000000000000000 R13: ffff88823869a2c8 R14: ffff8881012e0460 R15: dffffc0000000000 FS: 00007f350ac1f740(0000) GS:ffff8883ae200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f350a6ed6a0 CR3: 0000000237456000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? ext4_xattr_set_entry+0x3b7/0x2320 ? ext4_xattr_block_set+0x0/0x2020 ? ext4_xattr_set_entry+0x0/0x2320 ? ext4_xattr_check_entries+0x77/0x310 ? ext4_xattr_ibody_set+0x23b/0x340 ext4_xattr_move_to_block+0x594/0x720 ext4_expand_extra_isize_ea+0x59a/0x10f0 __ext4_expand_extra_isize+0x278/0x3f0 __ext4_mark_inode_dirty.cold+0x347/0x410 ext4_rename+0xed3/0x174f vfs_rename+0x13a7/0x2510 do_renameat2+0x55d/0x920 __x64_sys_rename+0x7d/0xb0 do_syscall_64+0x3b/0xa0 entry_SYSCALL_64_after_hwframe+0x72/0xdc As 'ext4_rename' will modify 'old.inode' ctime and mark inode dirty, which may trigger expand 'extra_isize' and allocate block. If inode didn't init quota will lead to warning. To solve above issue, init 'old.inode' firstly in 'ext4_rename'.

In the Linux kernel, the following vulnerability has been resolved: clocksource: hyper-v: unexport __init-annotated hv_init_clocksource() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, arch/x86/kernel/cpu/mshyperv.c is never compiled as modular. (CONFIG_HYPERVISOR_GUEST is boolean)

In the Linux kernel, the following vulnerability has been resolved: 9p: set req refcount to zero to avoid uninitialized usage When a new request is allocated, the refcount will be zero if it is reused, but if the request is newly allocated from slab, it is not fully initialized before being added to idr. If the p9_read_work got a response before the refcount initiated. It will use a uninitialized req, which will result in a bad request data struct. Here is the logs from syzbot. Corrupted memory at 0xffff88807eade00b [ 0xff 0x07 0x00 0x00 0x00 0x00 0x00 0x00 . . . . . . . . ] (in kfence-#110): p9_fcall_fini net/9p/client.c:248 [inline] p9_req_put net/9p/client.c:396 [inline] p9_req_put+0x208/0x250 net/9p/client.c:390 p9_client_walk+0x247/0x540 net/9p/client.c:1165 clone_fid fs/9p/fid.h:21 [inline] v9fs_fid_xattr_set+0xe4/0x2b0 fs/9p/xattr.c:118 v9fs_xattr_set fs/9p/xattr.c:100 [inline] v9fs_xattr_handler_set+0x6f/0x120 fs/9p/xattr.c:159 __vfs_setxattr+0x119/0x180 fs/xattr.c:182 __vfs_setxattr_noperm+0x129/0x5f0 fs/xattr.c:216 __vfs_setxattr_locked+0x1d3/0x260 fs/xattr.c:277 vfs_setxattr+0x143/0x340 fs/xattr.c:309 setxattr+0x146/0x160 fs/xattr.c:617 path_setxattr+0x197/0x1c0 fs/xattr.c:636 __do_sys_setxattr fs/xattr.c:652 [inline] __se_sys_setxattr fs/xattr.c:648 [inline] __ia32_sys_setxattr+0xc0/0x160 fs/xattr.c:648 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 Below is a similar scenario, the scenario in the syzbot log looks more complicated than this one, but this patch can fix it. T21124 p9_read_work ======================== second trans ================================= p9_client_walk p9_client_rpc p9_client_prepare_req p9_tag_alloc req = kmem_cache_alloc(p9_req_cache, GFP_NOFS); tag = idr_alloc << preempted >> req->tc.tag = tag; /* req->[refcount/tag] == uninitialized */ m->rreq = p9_tag_lookup(m->client, m->rc.tag); /* increments uninitalized refcount */ refcount_set(&req->refcount, 2); /* cb drops one ref */ p9_client_cb(req) /* reader thread drops its ref: request is incorrectly freed */ p9_req_put(req) /* use after free and ref underflow */ p9_req_put(req) To fix it, we can initialize the refcount to zero before add to idr.

In the Linux kernel, the following vulnerability has been resolved: iommu/mediatek: Fix crash on isr after kexec() If the system is rebooted via isr(), the IRQ handler might be triggered before the domain is initialized. Resulting on an invalid memory access error. Fix: [ 0.500930] Unable to handle kernel read from unreadable memory at virtual address 0000000000000070 [ 0.501166] Call trace: [ 0.501174] report_iommu_fault+0x28/0xfc [ 0.501180] mtk_iommu_isr+0x10c/0x1c0 [ joro: Fixed spelling in commit message ]

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix crash when mount with quota enabled There is a reported crash when mounting ocfs2 with quota enabled. RIP: 0010:ocfs2_qinfo_lock_res_init+0x44/0x50 [ocfs2] Call Trace: ocfs2_local_read_info+0xb9/0x6f0 [ocfs2] dquot_load_quota_sb+0x216/0x470 dquot_load_quota_inode+0x85/0x100 ocfs2_enable_quotas+0xa0/0x1c0 [ocfs2] ocfs2_fill_super.cold+0xc8/0x1bf [ocfs2] mount_bdev+0x185/0x1b0 legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 path_mount+0x465/0xac0 __x64_sys_mount+0x103/0x140 It is caused by when initializing dqi_gqlock, the corresponding dqi_type and dqi_sb are not properly initialized. This issue is introduced by commit 6c85c2c72819, which wants to avoid accessing uninitialized variables in error cases. So make global quota info properly initialized.

In the Linux kernel, the following vulnerability has been resolved: net: mdio: unexport __init-annotated mdio_bus_init() EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, drivers/net/phy/phy_device.c is never compiled as modular. (CONFIG_PHYLIB is boolean)

In the Linux kernel, the following vulnerability has been resolved: tipc: check attribute length for bearer name syzbot reported uninit-value: ===================================================== BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:644 [inline] BUG: KMSAN: uninit-value in string+0x4f9/0x6f0 lib/vsprintf.c:725 string_nocheck lib/vsprintf.c:644 [inline] string+0x4f9/0x6f0 lib/vsprintf.c:725 vsnprintf+0x2222/0x3650 lib/vsprintf.c:2806 vprintk_store+0x537/0x2150 kernel/printk/printk.c:2158 vprintk_emit+0x28b/0xab0 kernel/printk/printk.c:2256 vprintk_default+0x86/0xa0 kernel/printk/printk.c:2283 vprintk+0x15f/0x180 kernel/printk/printk_safe.c:50 _printk+0x18d/0x1cf kernel/printk/printk.c:2293 tipc_enable_bearer net/tipc/bearer.c:371 [inline] __tipc_nl_bearer_enable+0x2022/0x22a0 net/tipc/bearer.c:1033 tipc_nl_bearer_enable+0x6c/0xb0 net/tipc/bearer.c:1042 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline] - Do sanity check the attribute length for TIPC_NLA_BEARER_NAME. - Do not use 'illegal name' in printing message.

In the Linux kernel, the following vulnerability has been resolved: inet_diag: Initialize pad field in struct inet_diag_req_v2 KMSAN reported uninit-value access in raw_lookup() [1]. Diag for raw sockets uses the pad field in struct inet_diag_req_v2 for the underlying protocol. This field corresponds to the sdiag_raw_protocol field in struct inet_diag_req_raw. inet_diag_get_exact_compat() converts inet_diag_req to inet_diag_req_v2, but leaves the pad field uninitialized. So the issue occurs when raw_lookup() accesses the sdiag_raw_protocol field. Fix this by initializing the pad field in inet_diag_get_exact_compat(). Also, do the same fix in inet_diag_dump_compat() to avoid the similar issue in the future. [1] BUG: KMSAN: uninit-value in raw_lookup net/ipv4/raw_diag.c:49 [inline] BUG: KMSAN: uninit-value in raw_sock_get+0x657/0x800 net/ipv4/raw_diag.c:71 raw_lookup net/ipv4/raw_diag.c:49 [inline] raw_sock_get+0x657/0x800 net/ipv4/raw_diag.c:71 raw_diag_dump_one+0xa1/0x660 net/ipv4/raw_diag.c:99 inet_diag_cmd_exact+0x7d9/0x980 inet_diag_get_exact_compat net/ipv4/inet_diag.c:1404 [inline] inet_diag_rcv_msg_compat+0x469/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 netlink_rcv_skb+0x537/0x670 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x35/0x40 net/core/sock_diag.c:297 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0xe74/0x1240 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x10c6/0x1260 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x332/0x3d0 net/socket.c:745 ____sys_sendmsg+0x7f0/0xb70 net/socket.c:2585 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2639 __sys_sendmsg net/socket.c:2668 [inline] __do_sys_sendmsg net/socket.c:2677 [inline] __se_sys_sendmsg net/socket.c:2675 [inline] __x64_sys_sendmsg+0x27e/0x4a0 net/socket.c:2675 x64_sys_call+0x135e/0x3ce0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: raw_sock_get+0x650/0x800 net/ipv4/raw_diag.c:71 raw_diag_dump_one+0xa1/0x660 net/ipv4/raw_diag.c:99 inet_diag_cmd_exact+0x7d9/0x980 inet_diag_get_exact_compat net/ipv4/inet_diag.c:1404 [inline] inet_diag_rcv_msg_compat+0x469/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 netlink_rcv_skb+0x537/0x670 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x35/0x40 net/core/sock_diag.c:297 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0xe74/0x1240 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x10c6/0x1260 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x332/0x3d0 net/socket.c:745 ____sys_sendmsg+0x7f0/0xb70 net/socket.c:2585 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2639 __sys_sendmsg net/socket.c:2668 [inline] __do_sys_sendmsg net/socket.c:2677 [inline] __se_sys_sendmsg net/socket.c:2675 [inline] __x64_sys_sendmsg+0x27e/0x4a0 net/socket.c:2675 x64_sys_call+0x135e/0x3ce0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Local variable req.i created at: inet_diag_get_exact_compat net/ipv4/inet_diag.c:1396 [inline] inet_diag_rcv_msg_compat+0x2a6/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 CPU: 1 PID: 8888 Comm: syz-executor.6 Not tainted 6.10.0-rc4-00217-g35bb670d65fc #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014

In the Linux kernel, the following vulnerability has been resolved: net: hsr: avoid potential out-of-bound access in fill_frame_info() syzbot is able to feed a packet with 14 bytes, pretending it is a vlan one. Since fill_frame_info() is relying on skb->mac_len already, extend the check to cover this case. BUG: KMSAN: uninit-value in fill_frame_info net/hsr/hsr_forward.c:709 [inline] BUG: KMSAN: uninit-value in hsr_forward_skb+0x9ee/0x3b10 net/hsr/hsr_forward.c:724 fill_frame_info net/hsr/hsr_forward.c:709 [inline] hsr_forward_skb+0x9ee/0x3b10 net/hsr/hsr_forward.c:724 hsr_dev_xmit+0x2f0/0x350 net/hsr/hsr_device.c:235 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3606 __dev_queue_xmit+0x366a/0x57d0 net/core/dev.c:4434 dev_queue_xmit include/linux/netdevice.h:3168 [inline] packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3146 [inline] packet_sendmsg+0x91ae/0xa6f0 net/packet/af_packet.c:3178 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:726 __sys_sendto+0x594/0x750 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2200 x64_sys_call+0x346a/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4091 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4186 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587 __alloc_skb+0x363/0x7b0 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1323 [inline] alloc_skb_with_frags+0xc8/0xd00 net/core/skbuff.c:6612 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2881 packet_alloc_skb net/packet/af_packet.c:2995 [inline] packet_snd net/packet/af_packet.c:3089 [inline] packet_sendmsg+0x74c6/0xa6f0 net/packet/af_packet.c:3178 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x30f/0x380 net/socket.c:726 __sys_sendto+0x594/0x750 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0x125/0x1d0 net/socket.c:2200 x64_sys_call+0x346a/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init() During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE, since pageblock_order is still zero and it gets initialized later during initmem_init() e.g. setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order() One such use case where this causes issue is - early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init() This causes CMA memory alignment check to be bypassed in cma_init_reserved_mem(). Then later cma_activate_area() can hit a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory area was not pageblock_order aligned. Fix it by moving the fadump_cma_init() after initmem_init(), where other such cma reservations also gets called. <stack trace> ============== page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010 flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:778! Call Trace: __free_one_page+0x57c/0x7b0 (unreliable) free_pcppages_bulk+0x1a8/0x2c8 free_unref_page_commit+0x3d4/0x4e4 free_unref_page+0x458/0x6d0 init_cma_reserved_pageblock+0x114/0x198 cma_init_reserved_areas+0x270/0x3e0 do_one_initcall+0x80/0x2f8 kernel_init_freeable+0x33c/0x530 kernel_init+0x34/0x26c ret_from_kernel_user_thread+0x14/0x1c

In the Linux kernel, the following vulnerability has been resolved: ocfs2: free inode when ocfs2_get_init_inode() fails syzbot is reporting busy inodes after unmount, for commit 9c89fe0af826 ("ocfs2: Handle error from dquot_initialize()") forgot to call iput() when new_inode() succeeded and dquot_initialize() failed.

In the Linux kernel, the following vulnerability has been resolved: rtc: check if __rtc_read_time was successful in rtc_timer_do_work() If the __rtc_read_time call fails,, the struct rtc_time tm; may contain uninitialized data, or an illegal date/time read from the RTC hardware. When calling rtc_tm_to_ktime later, the result may be a very large value (possibly KTIME_MAX). If there are periodic timers in rtc->timerqueue, they will continually expire, may causing kernel softlockup.

In the Linux kernel, the following vulnerability has been resolved: media: dvb-frontends: dib3000mb: fix uninit-value in dib3000_write_reg Syzbot reports [1] an uninitialized value issue found by KMSAN in dib3000_read_reg(). Local u8 rb[2] is used in i2c_transfer() as a read buffer; in case that call fails, the buffer may end up with some undefined values. Since no elaborate error handling is expected in dib3000_write_reg(), simply zero out rb buffer to mitigate the problem. [1] Syzkaller report dvb-usb: bulk message failed: -22 (6/0) ===================================================== BUG: KMSAN: uninit-value in dib3000mb_attach+0x2d8/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758 dib3000mb_attach+0x2d8/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758 dibusb_dib3000mb_frontend_attach+0x155/0x2f0 drivers/media/usb/dvb-usb/dibusb-mb.c:31 dvb_usb_adapter_frontend_init+0xed/0x9a0 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:290 dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:90 [inline] dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:186 [inline] dvb_usb_device_init+0x25a8/0x3760 drivers/media/usb/dvb-usb/dvb-usb-init.c:310 dibusb_probe+0x46/0x250 drivers/media/usb/dvb-usb/dibusb-mb.c:110 ... Local variable rb created at: dib3000_read_reg+0x86/0x4e0 drivers/media/dvb-frontends/dib3000mb.c:54 dib3000mb_attach+0x123/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758 ...

In the Linux kernel, the following vulnerability has been resolved: fs: Fix uninitialized value issue in from_kuid and from_kgid ocfs2_setattr() uses attr->ia_mode, attr->ia_uid and attr->ia_gid in a trace point even though ATTR_MODE, ATTR_UID and ATTR_GID aren't set. Initialize all fields of newattrs to avoid uninitialized variables, by checking if ATTR_MODE, ATTR_UID, ATTR_GID are initialized, otherwise 0.

In the Linux kernel, the following vulnerability has been resolved: nfs: Fix KMSAN warning in decode_getfattr_attrs() Fix the following KMSAN warning: CPU: 1 UID: 0 PID: 7651 Comm: cp Tainted: G B Tainted: [B]=BAD_PAGE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) ===================================================== ===================================================== BUG: KMSAN: uninit-value in decode_getfattr_attrs+0x2d6d/0x2f90 decode_getfattr_attrs+0x2d6d/0x2f90 decode_getfattr_generic+0x806/0xb00 nfs4_xdr_dec_getattr+0x1de/0x240 rpcauth_unwrap_resp_decode+0xab/0x100 rpcauth_unwrap_resp+0x95/0xc0 call_decode+0x4ff/0xb50 __rpc_execute+0x57b/0x19d0 rpc_execute+0x368/0x5e0 rpc_run_task+0xcfe/0xee0 nfs4_proc_getattr+0x5b5/0x990 __nfs_revalidate_inode+0x477/0xd00 nfs_access_get_cached+0x1021/0x1cc0 nfs_do_access+0x9f/0xae0 nfs_permission+0x1e4/0x8c0 inode_permission+0x356/0x6c0 link_path_walk+0x958/0x1330 path_lookupat+0xce/0x6b0 filename_lookup+0x23e/0x770 vfs_statx+0xe7/0x970 vfs_fstatat+0x1f2/0x2c0 __se_sys_newfstatat+0x67/0x880 __x64_sys_newfstatat+0xbd/0x120 x64_sys_call+0x1826/0x3cf0 do_syscall_64+0xd0/0x1b0 entry_SYSCALL_64_after_hwframe+0x77/0x7f The KMSAN warning is triggered in decode_getfattr_attrs(), when calling decode_attr_mdsthreshold(). It appears that fattr->mdsthreshold is not initialized. Fix the issue by initializing fattr->mdsthreshold to NULL in nfs_fattr_init().

In the Linux kernel, the following vulnerability has been resolved: usb: typec: qcom-pmic: init value of hdr_len/txbuf_len earlier If the read of USB_PDPHY_RX_ACKNOWLEDGE_REG failed, then hdr_len and txbuf_len are uninitialized. This commit stops to print uninitialized value and misleading/false data.

In the Linux kernel, the following vulnerability has been resolved: ipvs: fix UB due to uninitialized stack access in ip_vs_protocol_init() Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f891bb9f ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) #23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) #24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB.

In the Linux kernel, the following vulnerability has been resolved: regulator: rtq2208: Fix uninitialized use of regulator_config Fix rtq2208 driver uninitialized use to cause kernel error.