In the Linux kernel, the following vulnerability has been resolved: btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount During the unmount path, at close_ctree(), we first stop the cleaner kthread, using kthread_stop() which frees the associated task_struct, and then stop and destroy all the work queues. However after we stopped the cleaner we may still have a worker from the delalloc_workers queue running inode.c:submit_compressed_extents(), which calls btrfs_add_delayed_iput(), which in turn tries to wake up the cleaner kthread - which was already destroyed before, resulting in a use-after-free on the task_struct. Syzbot reported this with the following stack traces: BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 Read of size 8 at addr ffff8880259d2818 by task kworker/u8:3/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: btrfs-delalloc btrfs_work_helper Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205 submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615 run_ordered_work fs/btrfs/async-thread.c:288 [inline] btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 2: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1113 copy_process+0x5d1/0x3d50 kernel/fork.c:2225 kernel_clone+0x223/0x870 kernel/fork.c:2807 kernel_thread+0x1bc/0x240 kernel/fork.c:2869 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:767 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 24: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4700 put_task_struct include/linux/sched/task.h:144 [inline] delayed_put_task_struct+0x125/0x300 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix slab-use-after-free due to dangling pointer dqi_priv When mounting ocfs2 and then remounting it as read-only, a slab-use-after-free occurs after the user uses a syscall to quota_getnextquota. Specifically, sb_dqinfo(sb, type)->dqi_priv is the dangling pointer. During the remounting process, the pointer dqi_priv is freed but is never set as null leaving it to be accessed. Additionally, the read-only option for remounting sets the DQUOT_SUSPENDED flag instead of setting the DQUOT_USAGE_ENABLED flags. Moreover, later in the process of getting the next quota, the function ocfs2_get_next_id is called and only checks the quota usage flags and not the quota suspended flags. To fix this, I set dqi_priv to null when it is freed after remounting with read-only and put a check for DQUOT_SUSPENDED in ocfs2_get_next_id. [akpm@linux-foundation.org: coding-style cleanups]

In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Fix slab-use-after-free read in sg_release() Fix a use-after-free bug in sg_release(), detected by syzbot with KASAN: BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5838 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:912 sg_release+0x1f4/0x2e0 drivers/scsi/sg.c:407 In sg_release(), the function kref_put(&sfp->f_ref, sg_remove_sfp) is called before releasing the open_rel_lock mutex. The kref_put() call may decrement the reference count of sfp to zero, triggering its cleanup through sg_remove_sfp(). This cleanup includes scheduling deferred work via sg_remove_sfp_usercontext(), which ultimately frees sfp. After kref_put(), sg_release() continues to unlock open_rel_lock and may reference sfp or sdp. If sfp has already been freed, this results in a slab-use-after-free error. Move the kref_put(&sfp->f_ref, sg_remove_sfp) call after unlocking the open_rel_lock mutex. This ensures: - No references to sfp or sdp occur after the reference count is decremented. - Cleanup functions such as sg_remove_sfp() and sg_remove_sfp_usercontext() can safely execute without impacting the mutex handling in sg_release(). The fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures proper sequencing of resource cleanup and mutex operations, eliminating the risk of use-after-free errors in sg_release().

In the Linux kernel, the following vulnerability has been resolved: net: avoid potential UAF in default_operstate() syzbot reported an UAF in default_operstate() [1] Issue is a race between device and netns dismantles. After calling __rtnl_unlock() from netdev_run_todo(), we can not assume the netns of each device is still alive. Make sure the device is not in NETREG_UNREGISTERED state, and add an ASSERT_RTNL() before the call to __dev_get_by_index(). We might move this ASSERT_RTNL() in __dev_get_by_index() in the future. [1] BUG: KASAN: slab-use-after-free in __dev_get_by_index+0x5d/0x110 net/core/dev.c:852 Read of size 8 at addr ffff888043eba1b0 by task syz.0.0/5339 CPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-10296-gaaf20f870da0 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __dev_get_by_index+0x5d/0x110 net/core/dev.c:852 default_operstate net/core/link_watch.c:51 [inline] rfc2863_policy+0x224/0x300 net/core/link_watch.c:67 linkwatch_do_dev+0x3e/0x170 net/core/link_watch.c:170 netdev_run_todo+0x461/0x1000 net/core/dev.c:10894 rtnl_unlock net/core/rtnetlink.c:152 [inline] rtnl_net_unlock include/linux/rtnetlink.h:133 [inline] rtnl_dellink+0x760/0x8d0 net/core/rtnetlink.c:3520 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6911 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2541 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x269/0x350 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a3cb80809 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2a3d9cd058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f2a3cd45fa0 RCX: 00007f2a3cb80809 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000008 RBP: 00007f2a3cbf393e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2a3cd45fa0 R15: 00007ffd03bc65c8 </TASK> Allocated by task 5339: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof include/linux/slab.h:901 [inline] kmalloc_array_noprof include/linux/slab.h:945 [inline] netdev_create_hash net/core/dev.c:11870 [inline] netdev_init+0x10c/0x250 net/core/dev.c:11890 ops_init+0x31e/0x590 net/core/net_namespace.c:138 setup_net+0x287/0x9e0 net/core/net_namespace.c:362 copy_net_ns+0x33f/0x570 net/core/net_namespace.c:500 create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x57d/0xa70 kernel/fork.c:3314 __do_sys_unshare kernel/fork.c:3385 [inline] __se_sys_unshare kernel/fork.c:3383 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:3383 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x8 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix slab-use-after-free Read in mgmt_remove_adv_monitor_sync This fixes the following crash: ================================================================== BUG: KASAN: slab-use-after-free in mgmt_remove_adv_monitor_sync+0x3a/0xd0 net/bluetooth/mgmt.c:5543 Read of size 8 at addr ffff88814128f898 by task kworker/u9:4/5961 CPU: 1 UID: 0 PID: 5961 Comm: kworker/u9:4 Not tainted 6.12.0-syzkaller-10684-gf1cd565ce577 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 mgmt_remove_adv_monitor_sync+0x3a/0xd0 net/bluetooth/mgmt.c:5543 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 16026: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] mgmt_pending_new+0x65/0x250 net/bluetooth/mgmt_util.c:269 mgmt_pending_add+0x36/0x120 net/bluetooth/mgmt_util.c:296 remove_adv_monitor+0x102/0x1b0 net/bluetooth/mgmt.c:5568 hci_mgmt_cmd+0xc47/0x11d0 net/bluetooth/hci_sock.c:1712 hci_sock_sendmsg+0x7b8/0x11c0 net/bluetooth/hci_sock.c:1832 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 sock_write_iter+0x2d7/0x3f0 net/socket.c:1147 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 16022: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kfree+0x196/0x420 mm/slub.c:4746 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x183/0x430 net/bluetooth/mgmt.c:9550 hci_dev_close_sync+0x6c4/0x11c0 net/bluetooth/hci_sync.c:5208 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_dev_close+0x112/0x210 net/bluetooth/hci_core.c:508 sock_do_ioctl+0x158/0x460 net/socket.c:1209 sock_ioctl+0x626/0x8e0 net/socket.c:1328 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: bpf: Reject struct_ops registration that uses module ptr and the module btf_id is missing There is a UAF report in the bpf_struct_ops when CONFIG_MODULES=n. In particular, the report is on tcp_congestion_ops that has a "struct module *owner" member. For struct_ops that has a "struct module *owner" member, it can be extended either by the regular kernel module or by the bpf_struct_ops. bpf_try_module_get() will be used to do the refcounting and different refcount is done based on the owner pointer. When CONFIG_MODULES=n, the btf_id of the "struct module" is missing: WARN: resolve_btfids: unresolved symbol module Thus, the bpf_try_module_get() cannot do the correct refcounting. Not all subsystem's struct_ops requires the "struct module *owner" member. e.g. the recent sched_ext_ops. This patch is to disable bpf_struct_ops registration if the struct_ops has the "struct module *" member and the "struct module" btf_id is missing. The btf_type_is_fwd() helper is moved to the btf.h header file for this test. This has happened since the beginning of bpf_struct_ops which has gone through many changes. The Fixes tag is set to a recent commit that this patch can apply cleanly. Considering CONFIG_MODULES=n is not common and the age of the issue, targeting for bpf-next also.

In the Linux kernel, the following vulnerability has been resolved: ila: serialize calls to nf_register_net_hooks() syzbot found a race in ila_add_mapping() [1] commit 031ae72825ce ("ila: call nf_unregister_net_hooks() sooner") attempted to fix a similar issue. Looking at the syzbot repro, we have concurrent ILA_CMD_ADD commands. Add a mutex to make sure at most one thread is calling nf_register_net_hooks(). [1] BUG: KASAN: slab-use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline] BUG: KASAN: slab-use-after-free in __rhashtable_lookup.constprop.0+0x426/0x550 include/linux/rhashtable.h:604 Read of size 4 at addr ffff888028f40008 by task dhcpcd/5501 CPU: 1 UID: 0 PID: 5501 Comm: dhcpcd Not tainted 6.13.0-rc4-syzkaller-00054-gd6ef8b40d075 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 rht_key_hashfn include/linux/rhashtable.h:159 [inline] __rhashtable_lookup.constprop.0+0x426/0x550 include/linux/rhashtable.h:604 rhashtable_lookup include/linux/rhashtable.h:646 [inline] rhashtable_lookup_fast include/linux/rhashtable.h:672 [inline] ila_lookup_wildcards net/ipv6/ila/ila_xlat.c:127 [inline] ila_xlat_addr net/ipv6/ila/ila_xlat.c:652 [inline] ila_nf_input+0x1ee/0x620 net/ipv6/ila/ila_xlat.c:185 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626 nf_hook.constprop.0+0x42e/0x750 include/linux/netfilter.h:269 NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0xa4/0x680 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x12e/0x1e0 net/core/dev.c:5672 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5785 process_backlog+0x443/0x15f0 net/core/dev.c:6117 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6883 napi_poll net/core/dev.c:6952 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7074 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049

In the Linux kernel, the following vulnerability has been resolved: fbmem: Do not delete the mode that is still in use The execution of fb_delete_videomode() is not based on the result of the previous fbcon_mode_deleted(). As a result, the mode is directly deleted, regardless of whether it is still in use, which may cause UAF. ================================================================== BUG: KASAN: use-after-free in fb_mode_is_equal+0x36e/0x5e0 \ drivers/video/fbdev/core/modedb.c:924 Read of size 4 at addr ffff88807e0ddb1c by task syz-executor.0/18962 CPU: 2 PID: 18962 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ... Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x137/0x1be lib/dump_stack.c:118 print_address_description+0x6c/0x640 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report+0x13d/0x1e0 mm/kasan/report.c:562 fb_mode_is_equal+0x36e/0x5e0 drivers/video/fbdev/core/modedb.c:924 fbcon_mode_deleted+0x16a/0x220 drivers/video/fbdev/core/fbcon.c:2746 fb_set_var+0x1e1/0xdb0 drivers/video/fbdev/core/fbmem.c:975 do_fb_ioctl+0x4d9/0x6e0 drivers/video/fbdev/core/fbmem.c:1108 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 18960: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:56 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0x108/0x140 mm/kasan/common.c:422 slab_free_hook mm/slub.c:1541 [inline] slab_free_freelist_hook+0xd6/0x1a0 mm/slub.c:1574 slab_free mm/slub.c:3139 [inline] kfree+0xca/0x3d0 mm/slub.c:4121 fb_delete_videomode+0x56a/0x820 drivers/video/fbdev/core/modedb.c:1104 fb_set_var+0x1f3/0xdb0 drivers/video/fbdev/core/fbmem.c:978 do_fb_ioctl+0x4d9/0x6e0 drivers/video/fbdev/core/fbmem.c:1108 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The dccp_disconnect function in net/dccp/proto.c in the Linux kernel through 4.14.3 allows local users to gain privileges or cause a denial of service (use-after-free) via an AF_UNSPEC connect system call during the DCCP_LISTEN state.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Skip restore TC rules for vport rep without loaded flag During driver unload, unregister_netdev is called after unloading vport rep. So, the mlx5e_rep_priv is already freed while trying to get rpriv->netdev, or walk rpriv->tc_ht, which results in use-after-free. So add the checking to make sure access the data of vport rep which is still loaded.

In the Linux kernel, the following vulnerability has been resolved: hrtimers: Handle CPU state correctly on hotplug Consider a scenario where a CPU transitions from CPUHP_ONLINE to halfway through a CPU hotunplug down to CPUHP_HRTIMERS_PREPARE, and then back to CPUHP_ONLINE: Since hrtimers_prepare_cpu() does not run, cpu_base.hres_active remains set to 1 throughout. However, during a CPU unplug operation, the tick and the clockevents are shut down at CPUHP_AP_TICK_DYING. On return to the online state, for instance CFS incorrectly assumes that the hrtick is already active, and the chance of the clockevent device to transition to oneshot mode is also lost forever for the CPU, unless it goes back to a lower state than CPUHP_HRTIMERS_PREPARE once. This round-trip reveals another issue; cpu_base.online is not set to 1 after the transition, which appears as a WARN_ON_ONCE in enqueue_hrtimer(). Aside of that, the bulk of the per CPU state is not reset either, which means there are dangling pointers in the worst case. Address this by adding a corresponding startup() callback, which resets the stale per CPU state and sets the online flag. [ tglx: Make the new callback unconditionally available, remove the online modification in the prepare() callback and clear the remaining state in the starting callback instead of the prepare callback ]

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Set private->all_drm_private[i]->drm to NULL if mtk_drm_bind returns err The pointer need to be set to NULL, otherwise KASAN complains about use-after-free. Because in mtk_drm_bind, all private's drm are set as follows. private->all_drm_private[i]->drm = drm; And drm will be released by drm_dev_put in case mtk_drm_kms_init returns failure. However, the shutdown path still accesses the previous allocated memory in drm_atomic_helper_shutdown. [ 84.874820] watchdog: watchdog0: watchdog did not stop! [ 86.512054] ================================================================== [ 86.513162] BUG: KASAN: use-after-free in drm_atomic_helper_shutdown+0x33c/0x378 [ 86.514258] Read of size 8 at addr ffff0000d46fc068 by task shutdown/1 [ 86.515213] [ 86.515455] CPU: 1 UID: 0 PID: 1 Comm: shutdown Not tainted 6.13.0-rc1-mtk+gfa1a78e5d24b-dirty #55 [ 86.516752] Hardware name: Unknown Product/Unknown Product, BIOS 2022.10 10/01/2022 [ 86.517960] Call trace: [ 86.518333] show_stack+0x20/0x38 (C) [ 86.518891] dump_stack_lvl+0x90/0xd0 [ 86.519443] print_report+0xf8/0x5b0 [ 86.519985] kasan_report+0xb4/0x100 [ 86.520526] __asan_report_load8_noabort+0x20/0x30 [ 86.521240] drm_atomic_helper_shutdown+0x33c/0x378 [ 86.521966] mtk_drm_shutdown+0x54/0x80 [ 86.522546] platform_shutdown+0x64/0x90 [ 86.523137] device_shutdown+0x260/0x5b8 [ 86.523728] kernel_restart+0x78/0xf0 [ 86.524282] __do_sys_reboot+0x258/0x2f0 [ 86.524871] __arm64_sys_reboot+0x90/0xd8 [ 86.525473] invoke_syscall+0x74/0x268 [ 86.526041] el0_svc_common.constprop.0+0xb0/0x240 [ 86.526751] do_el0_svc+0x4c/0x70 [ 86.527251] el0_svc+0x4c/0xc0 [ 86.527719] el0t_64_sync_handler+0x144/0x168 [ 86.528367] el0t_64_sync+0x198/0x1a0 [ 86.528920] [ 86.529157] The buggy address belongs to the physical page: [ 86.529972] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff0000d46fd4d0 pfn:0x1146fc [ 86.531319] flags: 0xbfffc0000000000(node=0|zone=2|lastcpupid=0xffff) [ 86.532267] raw: 0bfffc0000000000 0000000000000000 dead000000000122 0000000000000000 [ 86.533390] raw: ffff0000d46fd4d0 0000000000000000 00000000ffffffff 0000000000000000 [ 86.534511] page dumped because: kasan: bad access detected [ 86.535323] [ 86.535559] Memory state around the buggy address: [ 86.536265] ffff0000d46fbf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.537314] ffff0000d46fbf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.538363] >ffff0000d46fc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.544733] ^ [ 86.551057] ffff0000d46fc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.557510] ffff0000d46fc100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 86.563928] ================================================================== [ 86.571093] Disabling lock debugging due to kernel taint [ 86.577642] Unable to handle kernel paging request at virtual address e0e9c0920000000b [ 86.581834] KASAN: maybe wild-memory-access in range [0x0752049000000058-0x075204900000005f] ...

In the Linux kernel, the following vulnerability has been resolved: memory: tegra20-emc: fix an OF node reference bug in tegra_emc_find_node_by_ram_code() As of_find_node_by_name() release the reference of the argument device node, tegra_emc_find_node_by_ram_code() releases some device nodes while still in use, resulting in possible UAFs. According to the bindings and the in-tree DTS files, the "emc-tables" node is always device's child node with the property "nvidia,use-ram-code", and the "lpddr2" node is a child of the "emc-tables" node. Thus utilize the for_each_child_of_node() macro and of_get_child_by_name() instead of of_find_node_by_name() to simplify the code. This bug was found by an experimental verification tool that I am developing. [krzysztof: applied v1, adjust the commit msg to incorporate v2 parts]

In the Linux kernel, the following vulnerability has been resolved: powerpc/pseries/vas: Add close() callback in vas_vm_ops struct The mapping VMA address is saved in VAS window struct when the paste address is mapped. This VMA address is used during migration to unmap the paste address if the window is active. The paste address mapping will be removed when the window is closed or with the munmap(). But the VMA address in the VAS window is not updated with munmap() which is causing invalid access during migration. The KASAN report shows: [16386.254991] BUG: KASAN: slab-use-after-free in reconfig_close_windows+0x1a0/0x4e8 [16386.255043] Read of size 8 at addr c00000014a819670 by task drmgr/696928 [16386.255096] CPU: 29 UID: 0 PID: 696928 Comm: drmgr Kdump: loaded Tainted: G B 6.11.0-rc5-nxgzip #2 [16386.255128] Tainted: [B]=BAD_PAGE [16386.255148] Hardware name: IBM,9080-HEX Power11 (architected) 0x820200 0xf000007 of:IBM,FW1110.00 (NH1110_016) hv:phyp pSeries [16386.255181] Call Trace: [16386.255202] [c00000016b297660] [c0000000018ad0ac] dump_stack_lvl+0x84/0xe8 (unreliable) [16386.255246] [c00000016b297690] [c0000000006e8a90] print_report+0x19c/0x764 [16386.255285] [c00000016b297760] [c0000000006e9490] kasan_report+0x128/0x1f8 [16386.255309] [c00000016b297880] [c0000000006eb5c8] __asan_load8+0xac/0xe0 [16386.255326] [c00000016b2978a0] [c00000000013f898] reconfig_close_windows+0x1a0/0x4e8 [16386.255343] [c00000016b297990] [c000000000140e58] vas_migration_handler+0x3a4/0x3fc [16386.255368] [c00000016b297a90] [c000000000128848] pseries_migrate_partition+0x4c/0x4c4 ... [16386.256136] Allocated by task 696554 on cpu 31 at 16377.277618s: [16386.256149] kasan_save_stack+0x34/0x68 [16386.256163] kasan_save_track+0x34/0x80 [16386.256175] kasan_save_alloc_info+0x58/0x74 [16386.256196] __kasan_slab_alloc+0xb8/0xdc [16386.256209] kmem_cache_alloc_noprof+0x200/0x3d0 [16386.256225] vm_area_alloc+0x44/0x150 [16386.256245] mmap_region+0x214/0x10c4 [16386.256265] do_mmap+0x5fc/0x750 [16386.256277] vm_mmap_pgoff+0x14c/0x24c [16386.256292] ksys_mmap_pgoff+0x20c/0x348 [16386.256303] sys_mmap+0xd0/0x160 ... [16386.256350] Freed by task 0 on cpu 31 at 16386.204848s: [16386.256363] kasan_save_stack+0x34/0x68 [16386.256374] kasan_save_track+0x34/0x80 [16386.256384] kasan_save_free_info+0x64/0x10c [16386.256396] __kasan_slab_free+0x120/0x204 [16386.256415] kmem_cache_free+0x128/0x450 [16386.256428] vm_area_free_rcu_cb+0xa8/0xd8 [16386.256441] rcu_do_batch+0x2c8/0xcf0 [16386.256458] rcu_core+0x378/0x3c4 [16386.256473] handle_softirqs+0x20c/0x60c [16386.256495] do_softirq_own_stack+0x6c/0x88 [16386.256509] do_softirq_own_stack+0x58/0x88 [16386.256521] __irq_exit_rcu+0x1a4/0x20c [16386.256533] irq_exit+0x20/0x38 [16386.256544] interrupt_async_exit_prepare.constprop.0+0x18/0x2c ... [16386.256717] Last potentially related work creation: [16386.256729] kasan_save_stack+0x34/0x68 [16386.256741] __kasan_record_aux_stack+0xcc/0x12c [16386.256753] __call_rcu_common.constprop.0+0x94/0xd04 [16386.256766] vm_area_free+0x28/0x3c [16386.256778] remove_vma+0xf4/0x114 [16386.256797] do_vmi_align_munmap.constprop.0+0x684/0x870 [16386.256811] __vm_munmap+0xe0/0x1f8 [16386.256821] sys_munmap+0x54/0x6c [16386.256830] system_call_exception+0x1a0/0x4a0 [16386.256841] system_call_vectored_common+0x15c/0x2ec [16386.256868] The buggy address belongs to the object at c00000014a819670 which belongs to the cache vm_area_struct of size 168 [16386.256887] The buggy address is located 0 bytes inside of freed 168-byte region [c00000014a819670, c00000014a819718) [16386.256915] The buggy address belongs to the physical page: [16386.256928] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14a81 [16386.256950] memcg:c0000000ba430001 [16386.256961] anon flags: 0x43ffff800000000(node=4|zone=0|lastcpupid=0x7ffff) [16386.256975] page_type: 0xfdffffff(slab) [16386 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: drm: adv7511: Fix use-after-free in adv7533_attach_dsi() The host_node pointer was assigned and freed in adv7533_parse_dt(), and later, adv7533_attach_dsi() uses the same. Fix this use-after-free issue by dropping of_node_put() in adv7533_parse_dt() and calling of_node_put() in error path of probe() and also in the remove().

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Remove cache tags before disabling ATS The current implementation removes cache tags after disabling ATS, leading to potential memory leaks and kernel crashes. Specifically, CACHE_TAG_DEVTLB type cache tags may still remain in the list even after the domain is freed, causing a use-after-free condition. This issue really shows up when multiple VFs from different PFs passed through to a single user-space process via vfio-pci. In such cases, the kernel may crash with kernel messages like: BUG: kernel NULL pointer dereference, address: 0000000000000014 PGD 19036a067 P4D 1940a3067 PUD 136c9b067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 74 UID: 0 PID: 3183 Comm: testCli Not tainted 6.11.9 #2 RIP: 0010:cache_tag_flush_range+0x9b/0x250 Call Trace: <TASK> ? __die+0x1f/0x60 ? page_fault_oops+0x163/0x590 ? exc_page_fault+0x72/0x190 ? asm_exc_page_fault+0x22/0x30 ? cache_tag_flush_range+0x9b/0x250 ? cache_tag_flush_range+0x5d/0x250 intel_iommu_tlb_sync+0x29/0x40 intel_iommu_unmap_pages+0xfe/0x160 __iommu_unmap+0xd8/0x1a0 vfio_unmap_unpin+0x182/0x340 [vfio_iommu_type1] vfio_remove_dma+0x2a/0xb0 [vfio_iommu_type1] vfio_iommu_type1_ioctl+0xafa/0x18e0 [vfio_iommu_type1] Move cache_tag_unassign_domain() before iommu_disable_pci_caps() to fix it.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free when COWing tree bock and tracing is enabled When a COWing a tree block, at btrfs_cow_block(), and we have the tracepoint trace_btrfs_cow_block() enabled and preemption is also enabled (CONFIG_PREEMPT=y), we can trigger a use-after-free in the COWed extent buffer while inside the tracepoint code. This is because in some paths that call btrfs_cow_block(), such as btrfs_search_slot(), we are holding the last reference on the extent buffer @buf so btrfs_force_cow_block() drops the last reference on the @buf extent buffer when it calls free_extent_buffer_stale(buf), which schedules the release of the extent buffer with RCU. This means that if we are on a kernel with preemption, the current task may be preempted before calling trace_btrfs_cow_block() and the extent buffer already released by the time trace_btrfs_cow_block() is called, resulting in a use-after-free. Fix this by moving the trace_btrfs_cow_block() from btrfs_cow_block() to btrfs_force_cow_block() before the COWed extent buffer is freed. This also has a side effect of invoking the tracepoint in the tree defrag code, at defrag.c:btrfs_realloc_node(), since btrfs_force_cow_block() is called there, but this is fine and it was actually missing there.

In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Remove direct link to net_device Do not manage a per device direct link to net_device. Rely on associated ib_devices net_device management, not doubling the effort locally. A badly managed local link to net_device was causing a 'KASAN: slab-use-after-free' exception during siw_query_port() call.

In the Linux kernel, the following vulnerability has been resolved: iio: mma8452: Fix trigger reference couting The mma8452 driver directly assigns a trigger to the struct iio_dev. The IIO core when done using this trigger will call `iio_trigger_put()` to drop the reference count by 1. Without the matching `iio_trigger_get()` in the driver the reference count can reach 0 too early, the trigger gets freed while still in use and a use-after-free occurs. Fix this by getting a reference to the trigger before assigning it to the IIO device.

In the Linux kernel, the following vulnerability has been resolved: watchdog: Fix possible use-after-free by calling del_timer_sync() This driver's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: do not leave dangling sk pointer on error in l2cap_sock_create() bt_sock_alloc() allocates the sk object and attaches it to the provided sock object. On error l2cap_sock_alloc() frees the sk object, but the dangling pointer is still attached to the sock object, which may create use-after-free in other code.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix usage slab after free [ +0.000021] BUG: KASAN: slab-use-after-free in drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000027] Read of size 8 at addr ffff8881b8605f88 by task amd_pci_unplug/2147 [ +0.000023] CPU: 6 PID: 2147 Comm: amd_pci_unplug Not tainted 6.10.0+ #1 [ +0.000016] Hardware name: ASUS System Product Name/ROG STRIX B550-F GAMING (WI-FI), BIOS 1401 12/03/2020 [ +0.000016] Call Trace: [ +0.000008] <TASK> [ +0.000009] dump_stack_lvl+0x76/0xa0 [ +0.000017] print_report+0xce/0x5f0 [ +0.000017] ? drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000019] ? srso_return_thunk+0x5/0x5f [ +0.000015] ? kasan_complete_mode_report_info+0x72/0x200 [ +0.000016] ? drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000019] kasan_report+0xbe/0x110 [ +0.000015] ? drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000023] __asan_report_load8_noabort+0x14/0x30 [ +0.000014] drm_sched_entity_flush+0x6cb/0x7a0 [gpu_sched] [ +0.000020] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? __kasan_check_write+0x14/0x30 [ +0.000016] ? __pfx_drm_sched_entity_flush+0x10/0x10 [gpu_sched] [ +0.000020] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? __kasan_check_write+0x14/0x30 [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? enable_work+0x124/0x220 [ +0.000015] ? __pfx_enable_work+0x10/0x10 [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? free_large_kmalloc+0x85/0xf0 [ +0.000016] drm_sched_entity_destroy+0x18/0x30 [gpu_sched] [ +0.000020] amdgpu_vce_sw_fini+0x55/0x170 [amdgpu] [ +0.000735] ? __kasan_check_read+0x11/0x20 [ +0.000016] vce_v4_0_sw_fini+0x80/0x110 [amdgpu] [ +0.000726] amdgpu_device_fini_sw+0x331/0xfc0 [amdgpu] [ +0.000679] ? mutex_unlock+0x80/0xe0 [ +0.000017] ? __pfx_amdgpu_device_fini_sw+0x10/0x10 [amdgpu] [ +0.000662] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? __kasan_check_write+0x14/0x30 [ +0.000013] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? mutex_unlock+0x80/0xe0 [ +0.000016] amdgpu_driver_release_kms+0x16/0x80 [amdgpu] [ +0.000663] drm_minor_release+0xc9/0x140 [drm] [ +0.000081] drm_release+0x1fd/0x390 [drm] [ +0.000082] __fput+0x36c/0xad0 [ +0.000018] __fput_sync+0x3c/0x50 [ +0.000014] __x64_sys_close+0x7d/0xe0 [ +0.000014] x64_sys_call+0x1bc6/0x2680 [ +0.000014] do_syscall_64+0x70/0x130 [ +0.000014] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? irqentry_exit_to_user_mode+0x60/0x190 [ +0.000015] ? srso_return_thunk+0x5/0x5f [ +0.000014] ? irqentry_exit+0x43/0x50 [ +0.000012] ? srso_return_thunk+0x5/0x5f [ +0.000013] ? exc_page_fault+0x7c/0x110 [ +0.000015] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ +0.000014] RIP: 0033:0x7ffff7b14f67 [ +0.000013] Code: ff e8 0d 16 02 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 73 ba f7 ff [ +0.000026] RSP: 002b:00007fffffffe378 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ +0.000019] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffff7b14f67 [ +0.000014] RDX: 0000000000000000 RSI: 00007ffff7f6f47a RDI: 0000000000000003 [ +0.000014] RBP: 00007fffffffe3a0 R08: 0000555555569890 R09: 0000000000000000 [ +0.000014] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffffffe5c8 [ +0.000013] R13: 00005555555552a9 R14: 0000555555557d48 R15: 00007ffff7ffd040 [ +0.000020] </TASK> [ +0.000016] Allocated by task 383 on cpu 7 at 26.880319s: [ +0.000014] kasan_save_stack+0x28/0x60 [ +0.000008] kasan_save_track+0x18/0x70 [ +0.000007] kasan_save_alloc_info+0x38/0x60 [ +0.000007] __kasan_kmalloc+0xc1/0xd0 [ +0.000007] kmalloc_trace_noprof+0x180/0x380 [ +0.000007] drm_sched_init+0x411/0xec0 [gpu_sched] [ +0.000012] amdgpu_device_init+0x695f/0xa610 [amdgpu] [ +0.000658] amdgpu_driver_load_kms+0x1a/0x120 [amdgpu] [ +0.000662] amdgpu_pci_p ---truncated---

In the Linux kernel, the following vulnerability has been resolved: bus: mhi: core: Fix invalid error returning in mhi_queue mhi_queue returns an error when the doorbell is not accessible in the current state. This can happen when the device is in non M0 state, like M3, and needs to be waken-up prior ringing the DB. This case is managed earlier by triggering an asynchronous M3 exit via controller resume/suspend callbacks, that in turn will cause M0 transition and DB update. So, since it's not an error but just delaying of doorbell update, there is no reason to return an error. This also fixes a use after free error for skb case, indeed a caller queuing skb will try to free the skb if the queueing fails, but in that case queueing has been done.

In the Linux kernel, the following vulnerability has been resolved: nfsd: make sure exp active before svc_export_show The function `e_show` was called with protection from RCU. This only ensures that `exp` will not be freed. Therefore, the reference count for `exp` can drop to zero, which will trigger a refcount use-after-free warning when `exp_get` is called. To resolve this issue, use `cache_get_rcu` to ensure that `exp` remains active. ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 3 PID: 819 at lib/refcount.c:25 refcount_warn_saturate+0xb1/0x120 CPU: 3 UID: 0 PID: 819 Comm: cat Not tainted 6.12.0-rc3+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:refcount_warn_saturate+0xb1/0x120 ... Call Trace: <TASK> e_show+0x20b/0x230 [nfsd] seq_read_iter+0x589/0x770 seq_read+0x1e5/0x270 vfs_read+0x125/0x530 ksys_read+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e

In the Linux kernel, the following vulnerability has been resolved: ext4: fix possible UAF when remounting r/o a mmp-protected file system After commit 618f003199c6 ("ext4: fix memory leak in ext4_fill_super"), after the file system is remounted read-only, there is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to point at freed memory, which the call to ext4_stop_mmpd() can trip over. Fix this by only allowing kmmpd() to exit when it is stopped via ext4_stop_mmpd(). Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com>

In the Linux kernel, the following vulnerability has been resolved: net: ieee802154: do not leave a dangling sk pointer in ieee802154_create() sock_init_data() attaches the allocated sk object to the provided sock object. If ieee802154_create() fails later, the allocated sk object is freed, but the dangling pointer remains in the provided sock object, which may allow use-after-free. Clear the sk pointer in the sock object on error.

In the Linux kernel, the following vulnerability has been resolved: net: af_can: do not leave a dangling sk pointer in can_create() On error can_create() frees the allocated sk object, but sock_init_data() has already attached it to the provided sock object. This will leave a dangling sk pointer in the sock object and may cause use-after-free later.

In the Linux kernel, the following vulnerability has been resolved: ACPI: custom_method: fix potential use-after-free issue In cm_write(), buf is always freed when reaching the end of the function. If the requested count is less than table.length, the allocated buffer will be freed but subsequent calls to cm_write() will still try to access it. Remove the unconditional kfree(buf) at the end of the function and set the buf to NULL in the -EINVAL error path to match the rest of function.

In the Linux kernel, the following vulnerability has been resolved: regmap: set debugfs_name to NULL after it is freed There is a upstream commit cffa4b2122f5("regmap:debugfs: Fix a memory leak when calling regmap_attach_dev") that adds a if condition when create name for debugfs_name. With below function invoking logical, debugfs_name is freed in regmap_debugfs_exit(), but it is not created again because of the if condition introduced by above commit. regmap_reinit_cache() regmap_debugfs_exit() ... regmap_debugfs_init() So, set debugfs_name to NULL after it is freed.

Use-after-free vulnerability in fs/crypto/ in the Linux kernel before 4.10.7 allows local users to cause a denial of service (NULL pointer dereference) or possibly gain privileges by revoking keyring keys being used for ext4, f2fs, or ubifs encryption, causing cryptographic transform objects to be freed prematurely.

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: bsg: Set bsg_queue to NULL after removal Currently, this does not cause any issues, but I believe it is necessary to set bsg_queue to NULL after removing it to prevent potential use-after-free (UAF) access.

In the Linux kernel, the following vulnerability has been resolved: drm: bridge/panel: Cleanup connector on bridge detach If we don't call drm_connector_cleanup() manually in panel_bridge_detach(), the connector will be cleaned up with the other DRM objects in the call to drm_mode_config_cleanup(). However, since our drm_connector is devm-allocated, by the time drm_mode_config_cleanup() will be called, our connector will be long gone. Therefore, the connector must be cleaned up when the bridge is detached to avoid use-after-free conditions. v2: Cleanup connector only if it was created v3: Add FIXME v4: (Use connector->dev) directly in if() block

In the Linux kernel, the following vulnerability has been resolved: net: fix use-after-free in tw_timer_handler A real world panic issue was found as follow in Linux 5.4. BUG: unable to handle page fault for address: ffffde49a863de28 PGD 7e6fe62067 P4D 7e6fe62067 PUD 7e6fe63067 PMD f51e064067 PTE 0 RIP: 0010:tw_timer_handler+0x20/0x40 Call Trace: <IRQ> call_timer_fn+0x2b/0x120 run_timer_softirq+0x1ef/0x450 __do_softirq+0x10d/0x2b8 irq_exit+0xc7/0xd0 smp_apic_timer_interrupt+0x68/0x120 apic_timer_interrupt+0xf/0x20 This issue was also reported since 2017 in the thread [1], unfortunately, the issue was still can be reproduced after fixing DCCP. The ipv4_mib_exit_net is called before tcp_sk_exit_batch when a net namespace is destroyed since tcp_sk_ops is registered befrore ipv4_mib_ops, which means tcp_sk_ops is in the front of ipv4_mib_ops in the list of pernet_list. There will be a use-after-free on net->mib.net_statistics in tw_timer_handler after ipv4_mib_exit_net if there are some inflight time-wait timers. This bug is not introduced by commit f2bf415cfed7 ("mib: add net to NET_ADD_STATS_BH") since the net_statistics is a global variable instead of dynamic allocation and freeing. Actually, commit 61a7e26028b9 ("mib: put net statistics on struct net") introduces the bug since it put net statistics on struct net and free it when net namespace is destroyed. Moving init_ipv4_mibs() to the front of tcp_init() to fix this bug and replace pr_crit() with panic() since continuing is meaningless when init_ipv4_mibs() fails. [1] https://groups.google.com/g/syzkaller/c/p1tn-_Kc6l4/m/smuL_FMAAgAJ?pli=1

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Fix slab-use-after-free in scmi_bus_notifier() The scmi_dev->name is released prematurely in __scmi_device_destroy(), which causes slab-use-after-free when accessing scmi_dev->name in scmi_bus_notifier(). So move the release of scmi_dev->name to scmi_device_release() to avoid slab-use-after-free. | BUG: KASAN: slab-use-after-free in strncmp+0xe4/0xec | Read of size 1 at addr ffffff80a482bcc0 by task swapper/0/1 | | CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.6.38-debug #1 | Hardware name: Qualcomm Technologies, Inc. SA8775P Ride (DT) | Call trace: | dump_backtrace+0x94/0x114 | show_stack+0x18/0x24 | dump_stack_lvl+0x48/0x60 | print_report+0xf4/0x5b0 | kasan_report+0xa4/0xec | __asan_report_load1_noabort+0x20/0x2c | strncmp+0xe4/0xec | scmi_bus_notifier+0x5c/0x54c | notifier_call_chain+0xb4/0x31c | blocking_notifier_call_chain+0x68/0x9c | bus_notify+0x54/0x78 | device_del+0x1bc/0x840 | device_unregister+0x20/0xb4 | __scmi_device_destroy+0xac/0x280 | scmi_device_destroy+0x94/0xd0 | scmi_chan_setup+0x524/0x750 | scmi_probe+0x7fc/0x1508 | platform_probe+0xc4/0x19c | really_probe+0x32c/0x99c | __driver_probe_device+0x15c/0x3c4 | driver_probe_device+0x5c/0x170 | __driver_attach+0x1c8/0x440 | bus_for_each_dev+0xf4/0x178 | driver_attach+0x3c/0x58 | bus_add_driver+0x234/0x4d4 | driver_register+0xf4/0x3c0 | __platform_driver_register+0x60/0x88 | scmi_driver_init+0xb0/0x104 | do_one_initcall+0xb4/0x664 | kernel_init_freeable+0x3c8/0x894 | kernel_init+0x24/0x1e8 | ret_from_fork+0x10/0x20 | | Allocated by task 1: | kasan_save_stack+0x2c/0x54 | kasan_set_track+0x2c/0x40 | kasan_save_alloc_info+0x24/0x34 | __kasan_kmalloc+0xa0/0xb8 | __kmalloc_node_track_caller+0x6c/0x104 | kstrdup+0x48/0x84 | kstrdup_const+0x34/0x40 | __scmi_device_create.part.0+0x8c/0x408 | scmi_device_create+0x104/0x370 | scmi_chan_setup+0x2a0/0x750 | scmi_probe+0x7fc/0x1508 | platform_probe+0xc4/0x19c | really_probe+0x32c/0x99c | __driver_probe_device+0x15c/0x3c4 | driver_probe_device+0x5c/0x170 | __driver_attach+0x1c8/0x440 | bus_for_each_dev+0xf4/0x178 | driver_attach+0x3c/0x58 | bus_add_driver+0x234/0x4d4 | driver_register+0xf4/0x3c0 | __platform_driver_register+0x60/0x88 | scmi_driver_init+0xb0/0x104 | do_one_initcall+0xb4/0x664 | kernel_init_freeable+0x3c8/0x894 | kernel_init+0x24/0x1e8 | ret_from_fork+0x10/0x20 | | Freed by task 1: | kasan_save_stack+0x2c/0x54 | kasan_set_track+0x2c/0x40 | kasan_save_free_info+0x38/0x5c | __kasan_slab_free+0xe8/0x164 | __kmem_cache_free+0x11c/0x230 | kfree+0x70/0x130 | kfree_const+0x20/0x40 | __scmi_device_destroy+0x70/0x280 | scmi_device_destroy+0x94/0xd0 | scmi_chan_setup+0x524/0x750 | scmi_probe+0x7fc/0x1508 | platform_probe+0xc4/0x19c | really_probe+0x32c/0x99c | __driver_probe_device+0x15c/0x3c4 | driver_probe_device+0x5c/0x170 | __driver_attach+0x1c8/0x440 | bus_for_each_dev+0xf4/0x178 | driver_attach+0x3c/0x58 | bus_add_driver+0x234/0x4d4 | driver_register+0xf4/0x3c0 | __platform_driver_register+0x60/0x88 | scmi_driver_init+0xb0/0x104 | do_one_initcall+0xb4/0x664 | kernel_init_freeable+0x3c8/0x894 | kernel_init+0x24/0x1e8 | ret_from_fork+0x10/0x20

In the Linux kernel, the following vulnerability has been resolved: ubifs: authentication: Fix use-after-free in ubifs_tnc_end_commit After an insertion in TNC, the tree might split and cause a node to change its `znode->parent`. A further deletion of other nodes in the tree (which also could free the nodes), the aforementioned node's `znode->cparent` could still point to a freed node. This `znode->cparent` may not be updated when getting nodes to commit in `ubifs_tnc_start_commit()`. This could then trigger a use-after-free when accessing the `znode->cparent` in `write_index()` in `ubifs_tnc_end_commit()`. This can be triggered by running rm -f /etc/test-file.bin dd if=/dev/urandom of=/etc/test-file.bin bs=1M count=60 conv=fsync in a loop, and with `CONFIG_UBIFS_FS_AUTHENTICATION`. KASAN then reports: BUG: KASAN: use-after-free in ubifs_tnc_end_commit+0xa5c/0x1950 Write of size 32 at addr ffffff800a3af86c by task ubifs_bgt0_20/153 Call trace: dump_backtrace+0x0/0x340 show_stack+0x18/0x24 dump_stack_lvl+0x9c/0xbc print_address_description.constprop.0+0x74/0x2b0 kasan_report+0x1d8/0x1f0 kasan_check_range+0xf8/0x1a0 memcpy+0x84/0xf4 ubifs_tnc_end_commit+0xa5c/0x1950 do_commit+0x4e0/0x1340 ubifs_bg_thread+0x234/0x2e0 kthread+0x36c/0x410 ret_from_fork+0x10/0x20 Allocated by task 401: kasan_save_stack+0x38/0x70 __kasan_kmalloc+0x8c/0xd0 __kmalloc+0x34c/0x5bc tnc_insert+0x140/0x16a4 ubifs_tnc_add+0x370/0x52c ubifs_jnl_write_data+0x5d8/0x870 do_writepage+0x36c/0x510 ubifs_writepage+0x190/0x4dc __writepage+0x58/0x154 write_cache_pages+0x394/0x830 do_writepages+0x1f0/0x5b0 filemap_fdatawrite_wbc+0x170/0x25c file_write_and_wait_range+0x140/0x190 ubifs_fsync+0xe8/0x290 vfs_fsync_range+0xc0/0x1e4 do_fsync+0x40/0x90 __arm64_sys_fsync+0x34/0x50 invoke_syscall.constprop.0+0xa8/0x260 do_el0_svc+0xc8/0x1f0 el0_svc+0x34/0x70 el0t_64_sync_handler+0x108/0x114 el0t_64_sync+0x1a4/0x1a8 Freed by task 403: kasan_save_stack+0x38/0x70 kasan_set_track+0x28/0x40 kasan_set_free_info+0x28/0x4c __kasan_slab_free+0xd4/0x13c kfree+0xc4/0x3a0 tnc_delete+0x3f4/0xe40 ubifs_tnc_remove_range+0x368/0x73c ubifs_tnc_remove_ino+0x29c/0x2e0 ubifs_jnl_delete_inode+0x150/0x260 ubifs_evict_inode+0x1d4/0x2e4 evict+0x1c8/0x450 iput+0x2a0/0x3c4 do_unlinkat+0x2cc/0x490 __arm64_sys_unlinkat+0x90/0x100 invoke_syscall.constprop.0+0xa8/0x260 do_el0_svc+0xc8/0x1f0 el0_svc+0x34/0x70 el0t_64_sync_handler+0x108/0x114 el0t_64_sync+0x1a4/0x1a8 The offending `memcpy()` in `ubifs_copy_hash()` has a use-after-free when a node becomes root in TNC but still has a `cparent` to an already freed node. More specifically, consider the following TNC: zroot / / zp1 / / zn Inserting a new node `zn_new` with a key smaller then `zn` will trigger a split in `tnc_insert()` if `zp1` is full: zroot / \ / \ zp1 zp2 / \ / \ zn_new zn `zn->parent` has now been moved to `zp2`, *but* `zn->cparent` still points to `zp1`. Now, consider a removal of all the nodes _except_ `zn`. Just when `tnc_delete()` is about to delete `zroot` and `zp2`: zroot \ \ zp2 \ \ zn `zroot` and `zp2` get freed and the tree collapses: zn `zn` now becomes the new `zroot`. `get_znodes_to_commit()` will now only find `zn`, the new `zroot`, and `write_index()` will check its `znode->cparent` that wrongly points to the already freed `zp1`. `ubifs_copy_hash()` thus gets wrongly called with `znode->cparent->zbranch[znode->iip].hash` that triggers the use-after-free! Fix this by explicitly setting `znode->cparent` to `NULL` in `get_znodes_to_commit()` for the root node. The search for the dirty nodes ---truncated---

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix race in concurrent f2fs_stop_gc_thread In my test case, concurrent calls to f2fs shutdown report the following stack trace: Oops: general protection fault, probably for non-canonical address 0xc6cfff63bb5513fc: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 678 Comm: f2fs_rep_shutdo Not tainted 6.12.0-rc5-next-20241029-g6fb2fa9805c5-dirty #85 Call Trace: <TASK> ? show_regs+0x8b/0xa0 ? __die_body+0x26/0xa0 ? die_addr+0x54/0x90 ? exc_general_protection+0x24b/0x5c0 ? asm_exc_general_protection+0x26/0x30 ? kthread_stop+0x46/0x390 f2fs_stop_gc_thread+0x6c/0x110 f2fs_do_shutdown+0x309/0x3a0 f2fs_ioc_shutdown+0x150/0x1c0 __f2fs_ioctl+0xffd/0x2ac0 f2fs_ioctl+0x76/0xe0 vfs_ioctl+0x23/0x60 __x64_sys_ioctl+0xce/0xf0 x64_sys_call+0x2b1b/0x4540 do_syscall_64+0xa7/0x240 entry_SYSCALL_64_after_hwframe+0x76/0x7e The root cause is a race condition in f2fs_stop_gc_thread() called from different f2fs shutdown paths: [CPU0] [CPU1] ---------------------- ----------------------- f2fs_stop_gc_thread f2fs_stop_gc_thread gc_th = sbi->gc_thread gc_th = sbi->gc_thread kfree(gc_th) sbi->gc_thread = NULL < gc_th != NULL > kthread_stop(gc_th->f2fs_gc_task) //UAF The commit c7f114d864ac ("f2fs: fix to avoid use-after-free in f2fs_stop_gc_thread()") attempted to fix this issue by using a read semaphore to prevent races between shutdown and remount threads, but it fails to prevent all race conditions. Fix it by converting to write lock of s_umount in f2fs_do_shutdown().

In the Linux kernel, the following vulnerability has been resolved: fsnotify: Fix ordering of iput() and watched_objects decrement Ensure the superblock is kept alive until we're done with iput(). Holding a reference to an inode is not allowed unless we ensure the superblock stays alive, which fsnotify does by keeping the watched_objects count elevated, so iput() must happen before the watched_objects decrement. This can lead to a UAF of something like sb->s_fs_info in tmpfs, but the UAF is hard to hit because race orderings that oops are more likely, thanks to the CHECK_DATA_CORRUPTION() block in generic_shutdown_super(). Also, ensure that fsnotify_put_sb_watched_objects() doesn't call fsnotify_sb_watched_objects() on a superblock that may have already been freed, which would cause a UAF read of sb->s_fsnotify_info.

In the Linux kernel, the following vulnerability has been resolved: scsi: iscsi: Fix iscsi_task use after free Commit d39df158518c ("scsi: iscsi: Have abort handler get ref to conn") added iscsi_get_conn()/iscsi_put_conn() calls during abort handling but then also changed the handling of the case where we detect an already completed task where we now end up doing a goto to the common put/cleanup code. This results in a iscsi_task use after free, because the common cleanup code will do a put on the iscsi_task. This reverts the goto and moves the iscsi_get_conn() to after we've checked if the iscsi_task is valid.

In the Linux kernel, the following vulnerability has been resolved: sctp: fix possible UAF in sctp_v6_available() A lockdep report [1] with CONFIG_PROVE_RCU_LIST=y hints that sctp_v6_available() is calling dev_get_by_index_rcu() and ipv6_chk_addr() without holding rcu. [1] ============================= WARNING: suspicious RCU usage 6.12.0-rc5-virtme #1216 Tainted: G W ----------------------------- net/core/dev.c:876 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by sctp_hello/31495: #0: ffff9f1ebbdb7418 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_bind (./arch/x86/include/asm/jump_label.h:27 net/sctp/socket.c:315) sctp stack backtrace: CPU: 7 UID: 0 PID: 31495 Comm: sctp_hello Tainted: G W 6.12.0-rc5-virtme #1216 Tainted: [W]=WARN Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:123) lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822) dev_get_by_index_rcu (net/core/dev.c:876 (discriminator 7)) sctp_v6_available (net/sctp/ipv6.c:701) sctp sctp_do_bind (net/sctp/socket.c:400 (discriminator 1)) sctp sctp_bind (net/sctp/socket.c:320) sctp inet6_bind_sk (net/ipv6/af_inet6.c:465) ? security_socket_bind (security/security.c:4581 (discriminator 1)) __sys_bind (net/socket.c:1848 net/socket.c:1869) ? do_user_addr_fault (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340) ? do_user_addr_fault (./arch/x86/include/asm/preempt.h:84 (discriminator 13) ./include/linux/rcupdate.h:98 (discriminator 13) ./include/linux/rcupdate.h:882 (discriminator 13) ./include/linux/mm.h:729 (discriminator 13) arch/x86/mm/fault.c:1340 (discriminator 13)) __x64_sys_bind (net/socket.c:1877 (discriminator 1) net/socket.c:1875 (discriminator 1) net/socket.c:1875 (discriminator 1)) do_syscall_64 (arch/x86/entry/common.c:52 (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) RIP: 0033:0x7f59b934a1e7 Code: 44 00 00 48 8b 15 39 8c 0c 00 f7 d8 64 89 02 b8 ff ff ff ff eb bd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 b8 31 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 09 8c 0c 00 f7 d8 64 89 01 48 All code ======== 0: 44 00 00 add %r8b,(%rax) 3: 48 8b 15 39 8c 0c 00 mov 0xc8c39(%rip),%rdx # 0xc8c43 a: f7 d8 neg %eax c: 64 89 02 mov %eax,%fs:(%rdx) f: b8 ff ff ff ff mov $0xffffffff,%eax 14: eb bd jmp 0xffffffffffffffd3 16: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 1d: 00 00 00 20: 0f 1f 00 nopl (%rax) 23: b8 31 00 00 00 mov $0x31,%eax 28: 0f 05 syscall 2a:* 48 3d 01 f0 ff ff cmp $0xfffffffffffff001,%rax <-- trapping instruction 30: 73 01 jae 0x33 32: c3 ret 33: 48 8b 0d 09 8c 0c 00 mov 0xc8c09(%rip),%rcx # 0xc8c43 3a: f7 d8 neg %eax 3c: 64 89 01 mov %eax,%fs:(%rcx) 3f: 48 rex.W Code starting with the faulting instruction =========================================== 0: 48 3d 01 f0 ff ff cmp $0xfffffffffffff001,%rax 6: 73 01 jae 0x9 8: c3 ret 9: 48 8b 0d 09 8c 0c 00 mov 0xc8c09(%rip),%rcx # 0xc8c19 10: f7 d8 neg %eax 12: 64 89 01 mov %eax,%fs:(%rcx) 15: 48 rex.W RSP: 002b:00007ffe2d0ad398 EFLAGS: 00000202 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00007ffe2d0ad3d0 RCX: 00007f59b934a1e7 RDX: 000000000000001c RSI: 00007ffe2d0ad3d0 RDI: 0000000000000005 RBP: 0000000000000005 R08: 1999999999999999 R09: 0000000000000000 R10: 00007f59b9253298 R11: 000000000000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ALSA: 6fire: Release resources at card release The current 6fire code tries to release the resources right after the call of usb6fire_chip_abort(). But at this moment, the card object might be still in use (as we're calling snd_card_free_when_closed()). For avoid potential UAFs, move the release of resources to the card's private_free instead of the manual call of usb6fire_chip_destroy() at the USB disconnect callback.

In the Linux kernel, the following vulnerability has been resolved: smb: prevent use-after-free due to open_cached_dir error paths If open_cached_dir() encounters an error parsing the lease from the server, the error handling may race with receiving a lease break, resulting in open_cached_dir() freeing the cfid while the queued work is pending. Update open_cached_dir() to drop refs rather than directly freeing the cfid. Have cached_dir_lease_break(), cfids_laundromat_worker(), and invalidate_all_cached_dirs() clear has_lease immediately while still holding cfids->cfid_list_lock, and then use this to also simplify the reference counting in cfids_laundromat_worker() and invalidate_all_cached_dirs(). Fixes this KASAN splat (which manually injects an error and lease break in open_cached_dir()): ================================================================== BUG: KASAN: slab-use-after-free in smb2_cached_lease_break+0x27/0xb0 Read of size 8 at addr ffff88811cc24c10 by task kworker/3:1/65 CPU: 3 UID: 0 PID: 65 Comm: kworker/3:1 Not tainted 6.12.0-rc6-g255cf264e6e5-dirty #87 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 Workqueue: cifsiod smb2_cached_lease_break Call Trace: <TASK> dump_stack_lvl+0x77/0xb0 print_report+0xce/0x660 kasan_report+0xd3/0x110 smb2_cached_lease_break+0x27/0xb0 process_one_work+0x50a/0xc50 worker_thread+0x2ba/0x530 kthread+0x17c/0x1c0 ret_from_fork+0x34/0x60 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 2464: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_kmalloc+0xaa/0xb0 open_cached_dir+0xa7d/0x1fb0 smb2_query_path_info+0x43c/0x6e0 cifs_get_fattr+0x346/0xf10 cifs_get_inode_info+0x157/0x210 cifs_revalidate_dentry_attr+0x2d1/0x460 cifs_getattr+0x173/0x470 vfs_statx_path+0x10f/0x160 vfs_statx+0xe9/0x150 vfs_fstatat+0x5e/0xc0 __do_sys_newfstatat+0x91/0xf0 do_syscall_64+0x95/0x1a0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 2464: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x51/0x70 kfree+0x174/0x520 open_cached_dir+0x97f/0x1fb0 smb2_query_path_info+0x43c/0x6e0 cifs_get_fattr+0x346/0xf10 cifs_get_inode_info+0x157/0x210 cifs_revalidate_dentry_attr+0x2d1/0x460 cifs_getattr+0x173/0x470 vfs_statx_path+0x10f/0x160 vfs_statx+0xe9/0x150 vfs_fstatat+0x5e/0xc0 __do_sys_newfstatat+0x91/0xf0 do_syscall_64+0x95/0x1a0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Last potentially related work creation: kasan_save_stack+0x33/0x60 __kasan_record_aux_stack+0xad/0xc0 insert_work+0x32/0x100 __queue_work+0x5c9/0x870 queue_work_on+0x82/0x90 open_cached_dir+0x1369/0x1fb0 smb2_query_path_info+0x43c/0x6e0 cifs_get_fattr+0x346/0xf10 cifs_get_inode_info+0x157/0x210 cifs_revalidate_dentry_attr+0x2d1/0x460 cifs_getattr+0x173/0x470 vfs_statx_path+0x10f/0x160 vfs_statx+0xe9/0x150 vfs_fstatat+0x5e/0xc0 __do_sys_newfstatat+0x91/0xf0 do_syscall_64+0x95/0x1a0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff88811cc24c00 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 16 bytes inside of freed 1024-byte region [ffff88811cc24c00, ffff88811cc25000)

In the Linux kernel, the following vulnerability has been resolved: i40e: Fix use-after-free in i40e_client_subtask() Currently the call to i40e_client_del_instance frees the object pf->cinst, however pf->cinst->lan_info is being accessed after the free. Fix this by adding the missing return. Addresses-Coverity: ("Read from pointer after free")

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix slab-use-after-free in smb3_preauth_hash_rsp ksmbd_user_session_put should be called under smb3_preauth_hash_rsp(). It will avoid freeing session before calling smb3_preauth_hash_rsp().

In the Linux kernel, the following vulnerability has been resolved: netfilter: Fix use-after-free in get_info() ip6table_nat module unload has refcnt warning for UAF. call trace is: WARNING: CPU: 1 PID: 379 at kernel/module/main.c:853 module_put+0x6f/0x80 Modules linked in: ip6table_nat(-) CPU: 1 UID: 0 PID: 379 Comm: ip6tables Not tainted 6.12.0-rc4-00047-gc2ee9f594da8-dirty #205 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:module_put+0x6f/0x80 Call Trace: <TASK> get_info+0x128/0x180 do_ip6t_get_ctl+0x6a/0x430 nf_getsockopt+0x46/0x80 ipv6_getsockopt+0xb9/0x100 rawv6_getsockopt+0x42/0x190 do_sock_getsockopt+0xaa/0x180 __sys_getsockopt+0x70/0xc0 __x64_sys_getsockopt+0x20/0x30 do_syscall_64+0xa2/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Concurrent execution of module unload and get_info() trigered the warning. The root cause is as follows: cpu0 cpu1 module_exit //mod->state = MODULE_STATE_GOING ip6table_nat_exit xt_unregister_template kfree(t) //removed from templ_list getinfo() t = xt_find_table_lock list_for_each_entry(tmpl, &xt_templates[af]...) if (strcmp(tmpl->name, name)) continue; //table not found try_module_get list_for_each_entry(t, &xt_net->tables[af]...) return t; //not get refcnt module_put(t->me) //uaf unregister_pernet_subsys //remove table from xt_net list While xt_table module was going away and has been removed from xt_templates list, we couldnt get refcnt of xt_table->me. Check module in xt_net->tables list re-traversal to fix it.

In the Linux kernel, the following vulnerability has been resolved: net: sched: use RCU read-side critical section in taprio_dump() Fix possible use-after-free in 'taprio_dump()' by adding RCU read-side critical section there. Never seen on x86 but found on a KASAN-enabled arm64 system when investigating https://syzkaller.appspot.com/bug?extid=b65e0af58423fc8a73aa: [T15862] BUG: KASAN: slab-use-after-free in taprio_dump+0xa0c/0xbb0 [T15862] Read of size 4 at addr ffff0000d4bb88f8 by task repro/15862 [T15862] [T15862] CPU: 0 UID: 0 PID: 15862 Comm: repro Not tainted 6.11.0-rc1-00293-gdefaf1a2113a-dirty #2 [T15862] Hardware name: QEMU QEMU Virtual Machine, BIOS edk2-20240524-5.fc40 05/24/2024 [T15862] Call trace: [T15862] dump_backtrace+0x20c/0x220 [T15862] show_stack+0x2c/0x40 [T15862] dump_stack_lvl+0xf8/0x174 [T15862] print_report+0x170/0x4d8 [T15862] kasan_report+0xb8/0x1d4 [T15862] __asan_report_load4_noabort+0x20/0x2c [T15862] taprio_dump+0xa0c/0xbb0 [T15862] tc_fill_qdisc+0x540/0x1020 [T15862] qdisc_notify.isra.0+0x330/0x3a0 [T15862] tc_modify_qdisc+0x7b8/0x1838 [T15862] rtnetlink_rcv_msg+0x3c8/0xc20 [T15862] netlink_rcv_skb+0x1f8/0x3d4 [T15862] rtnetlink_rcv+0x28/0x40 [T15862] netlink_unicast+0x51c/0x790 [T15862] netlink_sendmsg+0x79c/0xc20 [T15862] __sock_sendmsg+0xe0/0x1a0 [T15862] ____sys_sendmsg+0x6c0/0x840 [T15862] ___sys_sendmsg+0x1ac/0x1f0 [T15862] __sys_sendmsg+0x110/0x1d0 [T15862] __arm64_sys_sendmsg+0x74/0xb0 [T15862] invoke_syscall+0x88/0x2e0 [T15862] el0_svc_common.constprop.0+0xe4/0x2a0 [T15862] do_el0_svc+0x44/0x60 [T15862] el0_svc+0x50/0x184 [T15862] el0t_64_sync_handler+0x120/0x12c [T15862] el0t_64_sync+0x190/0x194 [T15862] [T15862] Allocated by task 15857: [T15862] kasan_save_stack+0x3c/0x70 [T15862] kasan_save_track+0x20/0x3c [T15862] kasan_save_alloc_info+0x40/0x60 [T15862] __kasan_kmalloc+0xd4/0xe0 [T15862] __kmalloc_cache_noprof+0x194/0x334 [T15862] taprio_change+0x45c/0x2fe0 [T15862] tc_modify_qdisc+0x6a8/0x1838 [T15862] rtnetlink_rcv_msg+0x3c8/0xc20 [T15862] netlink_rcv_skb+0x1f8/0x3d4 [T15862] rtnetlink_rcv+0x28/0x40 [T15862] netlink_unicast+0x51c/0x790 [T15862] netlink_sendmsg+0x79c/0xc20 [T15862] __sock_sendmsg+0xe0/0x1a0 [T15862] ____sys_sendmsg+0x6c0/0x840 [T15862] ___sys_sendmsg+0x1ac/0x1f0 [T15862] __sys_sendmsg+0x110/0x1d0 [T15862] __arm64_sys_sendmsg+0x74/0xb0 [T15862] invoke_syscall+0x88/0x2e0 [T15862] el0_svc_common.constprop.0+0xe4/0x2a0 [T15862] do_el0_svc+0x44/0x60 [T15862] el0_svc+0x50/0x184 [T15862] el0t_64_sync_handler+0x120/0x12c [T15862] el0t_64_sync+0x190/0x194 [T15862] [T15862] Freed by task 6192: [T15862] kasan_save_stack+0x3c/0x70 [T15862] kasan_save_track+0x20/0x3c [T15862] kasan_save_free_info+0x4c/0x80 [T15862] poison_slab_object+0x110/0x160 [T15862] __kasan_slab_free+0x3c/0x74 [T15862] kfree+0x134/0x3c0 [T15862] taprio_free_sched_cb+0x18c/0x220 [T15862] rcu_core+0x920/0x1b7c [T15862] rcu_core_si+0x10/0x1c [T15862] handle_softirqs+0x2e8/0xd64 [T15862] __do_softirq+0x14/0x20

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for accessing waker_bfqq after splitting After commit 42c306ed7233 ("block, bfq: don't break merge chain in bfq_split_bfqq()"), if the current procress is the last holder of bfqq, the bfqq can be freed after bfq_split_bfqq(). Hence recored the bfqq and then access bfqq->waker_bfqq may trigger UAF. What's more, the waker_bfqq may in the merge chain of bfqq, hence just recored waker_bfqq is still not safe. Fix the problem by adding a helper bfq_waker_bfqq() to check if bfqq->waker_bfqq is in the merge chain, and current procress is the only holder.

In the Linux kernel, the following vulnerability has been resolved: spi: mpc52xx: Add cancel_work_sync before module remove If we remove the module which will call mpc52xx_spi_remove it will free 'ms' through spi_unregister_controller. while the work ms->work will be used. The sequence of operations that may lead to a UAF bug. Fix it by ensuring that the work is canceled before proceeding with the cleanup in mpc52xx_spi_remove.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix slab-use-after-free in ksmbd_smb2_session_create There is a race condition between ksmbd_smb2_session_create and ksmbd_expire_session. This patch add missing sessions_table_lock while adding/deleting session from global session table.

In the Linux kernel, the following vulnerability has been resolved: ext4: avoid use-after-free in ext4_ext_show_leaf() In ext4_find_extent(), path may be freed by error or be reallocated, so using a previously saved *ppath may have been freed and thus may trigger use-after-free, as follows: ext4_split_extent path = *ppath; ext4_split_extent_at(ppath) path = ext4_find_extent(ppath) ext4_split_extent_at(ppath) // ext4_find_extent fails to free path // but zeroout succeeds ext4_ext_show_leaf(inode, path) eh = path[depth].p_hdr // path use-after-free !!! Similar to ext4_split_extent_at(), we use *ppath directly as an input to ext4_ext_show_leaf(). Fix a spelling error by the way. Same problem in ext4_ext_handle_unwritten_extents(). Since 'path' is only used in ext4_ext_show_leaf(), remove 'path' and use *ppath directly. This issue is triggered only when EXT_DEBUG is defined and therefore does not affect functionality.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix user-after-free from session log off There is racy issue between smb2 session log off and smb2 session setup. It will cause user-after-free from session log off. This add session_lock when setting SMB2_SESSION_EXPIRED and referece count to session struct not to free session while it is being used.