The Linux kernel before 6.5.4 has an es1 use-after-free in fs/ext4/extents_status.c, related to ext4_es_insert_extent.

In Ubuntu's accountsservice an unprivileged local attacker can trigger a use-after-free vulnerability in accountsservice by sending a D-Bus message to the accounts-daemon process.

In the Linux kernel, the following vulnerability has been resolved: bridge: mcast: Fix use-after-free during router port configuration The bridge maintains a global list of ports behind which a multicast router resides. The list is consulted during forwarding to ensure multicast packets are forwarded to these ports even if the ports are not member in the matching MDB entry. When per-VLAN multicast snooping is enabled, the per-port multicast context is disabled on each port and the port is removed from the global router port list: # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 # ip link add name dummy1 up master br1 type dummy # ip link set dev dummy1 type bridge_slave mcast_router 2 $ bridge -d mdb show | grep router router ports on br1: dummy1 # ip link set dev br1 type bridge mcast_vlan_snooping 1 $ bridge -d mdb show | grep router However, the port can be re-added to the global list even when per-VLAN multicast snooping is enabled: # ip link set dev dummy1 type bridge_slave mcast_router 0 # ip link set dev dummy1 type bridge_slave mcast_router 2 $ bridge -d mdb show | grep router router ports on br1: dummy1 Since commit 4b30ae9adb04 ("net: bridge: mcast: re-implement br_multicast_{enable, disable}_port functions"), when per-VLAN multicast snooping is enabled, multicast disablement on a port will disable the per-{port, VLAN} multicast contexts and not the per-port one. As a result, a port will remain in the global router port list even after it is deleted. This will lead to a use-after-free [1] when the list is traversed (when adding a new port to the list, for example): # ip link del dev dummy1 # ip link add name dummy2 up master br1 type dummy # ip link set dev dummy2 type bridge_slave mcast_router 2 Similarly, stale entries can also be found in the per-VLAN router port list. When per-VLAN multicast snooping is disabled, the per-{port, VLAN} contexts are disabled on each port and the port is removed from the per-VLAN router port list: # ip link add name br1 up type bridge vlan_filtering 1 mcast_snooping 1 mcast_vlan_snooping 1 # ip link add name dummy1 up master br1 type dummy # bridge vlan add vid 2 dev dummy1 # bridge vlan global set vid 2 dev br1 mcast_snooping 1 # bridge vlan set vid 2 dev dummy1 mcast_router 2 $ bridge vlan global show dev br1 vid 2 | grep router router ports: dummy1 # ip link set dev br1 type bridge mcast_vlan_snooping 0 $ bridge vlan global show dev br1 vid 2 | grep router However, the port can be re-added to the per-VLAN list even when per-VLAN multicast snooping is disabled: # bridge vlan set vid 2 dev dummy1 mcast_router 0 # bridge vlan set vid 2 dev dummy1 mcast_router 2 $ bridge vlan global show dev br1 vid 2 | grep router router ports: dummy1 When the VLAN is deleted from the port, the per-{port, VLAN} multicast context will not be disabled since multicast snooping is not enabled on the VLAN. As a result, the port will remain in the per-VLAN router port list even after it is no longer member in the VLAN. This will lead to a use-after-free [2] when the list is traversed (when adding a new port to the list, for example): # ip link add name dummy2 up master br1 type dummy # bridge vlan add vid 2 dev dummy2 # bridge vlan del vid 2 dev dummy1 # bridge vlan set vid 2 dev dummy2 mcast_router 2 Fix these issues by removing the port from the relevant (global or per-VLAN) router port list in br_multicast_port_ctx_deinit(). The function is invoked during port deletion with the per-port multicast context and during VLAN deletion with the per-{port, VLAN} multicast context. Note that deleting the multicast router timer is not enough as it only takes care of the temporary multicast router states (1 or 3) and not the permanent one (2). [1] BUG: KASAN: slab-out-of-bounds in br_multicast_add_router.part.0+0x3f1/0x560 Write of size 8 at addr ffff888004a67328 by task ip/384 [...] Call Trace: <TASK> dump_stack ---truncated---

In the Linux kernel, the following vulnerability has been resolved: net/sched: Always pass notifications when child class becomes empty Certain classful qdiscs may invoke their classes' dequeue handler on an enqueue operation. This may unexpectedly empty the child qdisc and thus make an in-flight class passive via qlen_notify(). Most qdiscs do not expect such behaviour at this point in time and may re-activate the class eventually anyways which will lead to a use-after-free. The referenced fix commit attempted to fix this behavior for the HFSC case by moving the backlog accounting around, though this turned out to be incomplete since the parent's parent may run into the issue too. The following reproducer demonstrates this use-after-free: tc qdisc add dev lo root handle 1: drr tc filter add dev lo parent 1: basic classid 1:1 tc class add dev lo parent 1: classid 1:1 drr tc qdisc add dev lo parent 1:1 handle 2: hfsc def 1 tc class add dev lo parent 2: classid 2:1 hfsc rt m1 8 d 1 m2 0 tc qdisc add dev lo parent 2:1 handle 3: netem tc qdisc add dev lo parent 3:1 handle 4: blackhole echo 1 | socat -u STDIN UDP4-DATAGRAM:127.0.0.1:8888 tc class delete dev lo classid 1:1 echo 1 | socat -u STDIN UDP4-DATAGRAM:127.0.0.1:8888 Since backlog accounting issues leading to a use-after-frees on stale class pointers is a recurring pattern at this point, this patch takes a different approach. Instead of trying to fix the accounting, the patch ensures that qdisc_tree_reduce_backlog always calls qlen_notify when the child qdisc is empty. This solves the problem because deletion of qdiscs always involves a call to qdisc_reset() and / or qdisc_purge_queue() which ultimately resets its qlen to 0 thus causing the following qdisc_tree_reduce_backlog() to report to the parent. Note that this may call qlen_notify on passive classes multiple times. This is not a problem after the recent patch series that made all the classful qdiscs qlen_notify() handlers idempotent.

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix waker_bfqq UAF after bfq_split_bfqq() Our syzkaller report a following UAF for v6.6: BUG: KASAN: slab-use-after-free in bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958 Read of size 8 at addr ffff8881b57147d8 by task fsstress/232726 CPU: 2 PID: 232726 Comm: fsstress Not tainted 6.6.0-g3629d1885222 #39 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106 print_address_description.constprop.0+0x66/0x300 mm/kasan/report.c:364 print_report+0x3e/0x70 mm/kasan/report.c:475 kasan_report+0xb8/0xf0 mm/kasan/report.c:588 hlist_add_head include/linux/list.h:1023 [inline] bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143 __submit_bio+0xa0/0x6b0 block/blk-core.c:639 __submit_bio_noacct_mq block/blk-core.c:718 [inline] submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847 __ext4_read_bh fs/ext4/super.c:205 [inline] ext4_read_bh+0x15e/0x2e0 fs/ext4/super.c:230 __read_extent_tree_block+0x304/0x6f0 fs/ext4/extents.c:567 ext4_find_extent+0x479/0xd20 fs/ext4/extents.c:947 ext4_ext_map_blocks+0x1a3/0x2680 fs/ext4/extents.c:4182 ext4_map_blocks+0x929/0x15a0 fs/ext4/inode.c:660 ext4_iomap_begin_report+0x298/0x480 fs/ext4/inode.c:3569 iomap_iter+0x3dd/0x1010 fs/iomap/iter.c:91 iomap_fiemap+0x1f4/0x360 fs/iomap/fiemap.c:80 ext4_fiemap+0x181/0x210 fs/ext4/extents.c:5051 ioctl_fiemap.isra.0+0x1b4/0x290 fs/ioctl.c:220 do_vfs_ioctl+0x31c/0x11a0 fs/ioctl.c:811 __do_sys_ioctl fs/ioctl.c:869 [inline] __se_sys_ioctl+0xae/0x190 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x78/0xe2 Allocated by task 232719: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:768 [inline] slab_alloc_node mm/slub.c:3492 [inline] kmem_cache_alloc_node+0x1b8/0x6f0 mm/slub.c:3537 bfq_get_queue+0x215/0x1f00 block/bfq-iosched.c:5869 bfq_get_bfqq_handle_split+0x167/0x5f0 block/bfq-iosched.c:6776 bfq_init_rq+0x13a4/0x17a0 block/bfq-iosched.c:6938 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143 __submit_bio+0xa0/0x6b0 block/blk-core.c:639 __submit_bio_noacct_mq block/blk-core.c:718 [inline] submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847 __ext4_read_bh fs/ext4/super.c:205 [inline] ext4_read_bh_nowait+0x15a/0x240 fs/ext4/super.c:217 ext4_read_bh_lock+0xac/0xd0 fs/ext4/super.c:242 ext4_bread_batch+0x268/0x500 fs/ext4/inode.c:958 __ext4_find_entry+0x448/0x10f0 fs/ext4/namei.c:1671 ext4_lookup_entry fs/ext4/namei.c:1774 [inline] ext4_lookup.part.0+0x359/0x6f0 fs/ext4/namei.c:1842 ext4_lookup+0x72/0x90 fs/ext4/namei.c:1839 __lookup_slow+0x257/0x480 fs/namei.c:1696 lookup_slow fs/namei.c:1713 [inline] walk_component+0x454/0x5c0 fs/namei.c:2004 link_path_walk.part.0+0x773/0xda0 fs/namei.c:2331 link_path_walk fs/namei.c:3826 [inline] path_openat+0x1b9/0x520 fs/namei.c:3826 do_filp_open+0x1b7/0x400 fs/namei.c:3857 do_sys_openat2+0x5dc/0x6e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x148/0x200 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_6 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: veth: Fix use after free in XDP_REDIRECT Commit 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb") introduced a bug where it tried to use pskb_expand_head() if the headroom was less than XDP_PACKET_HEADROOM. This however uses kmalloc to expand the head, which will later allow consume_skb() to free the skb while is it still in use by AF_XDP. Previously if the headroom was less than XDP_PACKET_HEADROOM we continued on to allocate a new skb from pages so this restores that behavior. BUG: KASAN: use-after-free in __xsk_rcv+0x18d/0x2c0 Read of size 78 at addr ffff888976250154 by task napi/iconduit-g/148640 CPU: 5 PID: 148640 Comm: napi/iconduit-g Kdump: loaded Tainted: G O 6.1.4-cloudflare-kasan-2023.1.2 #1 Hardware name: Quanta Computer Inc. QuantaPlex T41S-2U/S2S-MB, BIOS S2S_3B10.03 06/21/2018 Call Trace: <TASK> dump_stack_lvl+0x34/0x48 print_report+0x170/0x473 ? __xsk_rcv+0x18d/0x2c0 kasan_report+0xad/0x130 ? __xsk_rcv+0x18d/0x2c0 kasan_check_range+0x149/0x1a0 memcpy+0x20/0x60 __xsk_rcv+0x18d/0x2c0 __xsk_map_redirect+0x1f3/0x490 ? veth_xdp_rcv_skb+0x89c/0x1ba0 [veth] xdp_do_redirect+0x5ca/0xd60 veth_xdp_rcv_skb+0x935/0x1ba0 [veth] ? __netif_receive_skb_list_core+0x671/0x920 ? veth_xdp+0x670/0x670 [veth] veth_xdp_rcv+0x304/0xa20 [veth] ? do_xdp_generic+0x150/0x150 ? veth_xdp_rcv_one+0xde0/0xde0 [veth] ? _raw_spin_lock_bh+0xe0/0xe0 ? newidle_balance+0x887/0xe30 ? __perf_event_task_sched_in+0xdb/0x800 veth_poll+0x139/0x571 [veth] ? veth_xdp_rcv+0xa20/0xa20 [veth] ? _raw_spin_unlock+0x39/0x70 ? finish_task_switch.isra.0+0x17e/0x7d0 ? __switch_to+0x5cf/0x1070 ? __schedule+0x95b/0x2640 ? io_schedule_timeout+0x160/0x160 __napi_poll+0xa1/0x440 napi_threaded_poll+0x3d1/0x460 ? __napi_poll+0x440/0x440 ? __kthread_parkme+0xc6/0x1f0 ? __napi_poll+0x440/0x440 kthread+0x2a2/0x340 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x22/0x30 </TASK> Freed by task 148640: kasan_save_stack+0x23/0x50 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x40 ____kasan_slab_free+0x169/0x1d0 slab_free_freelist_hook+0xd2/0x190 __kmem_cache_free+0x1a1/0x2f0 skb_release_data+0x449/0x600 consume_skb+0x9f/0x1c0 veth_xdp_rcv_skb+0x89c/0x1ba0 [veth] veth_xdp_rcv+0x304/0xa20 [veth] veth_poll+0x139/0x571 [veth] __napi_poll+0xa1/0x440 napi_threaded_poll+0x3d1/0x460 kthread+0x2a2/0x340 ret_from_fork+0x22/0x30 The buggy address belongs to the object at ffff888976250000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 340 bytes inside of 2048-byte region [ffff888976250000, ffff888976250800) The buggy address belongs to the physical page: page:00000000ae18262a refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x976250 head:00000000ae18262a order:3 compound_mapcount:0 compound_pincount:0 flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) raw: 002ffff800010200 0000000000000000 dead000000000122 ffff88810004cf00 raw: 0000000000000000 0000000080080008 00000002ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888976250000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888976250080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888976250100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888976250180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888976250200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

In drivers/net/ethernet/hisilicon/hns/hns_enet.c in the Linux kernel before 4.13, local users can cause a denial of service (use-after-free and BUG) or possibly have unspecified other impact by leveraging differences in skb handling between hns_nic_net_xmit_hw and hns_nic_net_xmit.

The mm_init function in kernel/fork.c in the Linux kernel before 4.12.10 does not clear the ->exe_file member of a new process's mm_struct, allowing a local attacker to achieve a use-after-free or possibly have unspecified other impact by running a specially crafted program.

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: avoid a use-after-free when BO init fails nouveau_bo_init() is backed by ttm_bo_init() and ferries its return code back to the caller. On failures, ttm_bo_init() invokes the provided destructor which should de-initialize and free the memory. Thus, when nouveau_bo_init() returns an error the gem object has already been released and the memory freed by nouveau_bo_del_ttm().

In the Linux kernel, the following vulnerability has been resolved: media: atomisp: Fix use after free in atomisp_alloc_css_stat_bufs() The "s3a_buf" is freed along with all the other items on the "asd->s3a_stats" list. It leads to a double free and a use after free.

In the Linux kernel, the following vulnerability has been resolved: mm/debug_vm_pgtable: clear page table entries at destroy_args() The mm/debug_vm_pagetable test allocates manually page table entries for the tests it runs, using also its manually allocated mm_struct. That in itself is ok, but when it exits, at destroy_args() it fails to clear those entries with the *_clear functions. The problem is that leaves stale entries. If another process allocates an mm_struct with a pgd at the same address, it may end up running into the stale entry. This is happening in practice on a debug kernel with CONFIG_DEBUG_VM_PGTABLE=y, for example this is the output with some extra debugging I added (it prints a warning trace if pgtables_bytes goes negative, in addition to the warning at check_mm() function): [ 2.539353] debug_vm_pgtable: [get_random_vaddr ]: random_vaddr is 0x7ea247140000 [ 2.539366] kmem_cache info [ 2.539374] kmem_cachep 0x000000002ce82385 - freelist 0x0000000000000000 - offset 0x508 [ 2.539447] debug_vm_pgtable: [init_args ]: args->mm is 0x000000002267cc9e (...) [ 2.552800] WARNING: CPU: 5 PID: 116 at include/linux/mm.h:2841 free_pud_range+0x8bc/0x8d0 [ 2.552816] Modules linked in: [ 2.552843] CPU: 5 UID: 0 PID: 116 Comm: modprobe Not tainted 6.12.0-105.debug_vm2.el10.ppc64le+debug #1 VOLUNTARY [ 2.552859] Hardware name: IBM,9009-41A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW910.00 (VL910_062) hv:phyp pSeries [ 2.552872] NIP: c0000000007eef3c LR: c0000000007eef30 CTR: c0000000003d8c90 [ 2.552885] REGS: c0000000622e73b0 TRAP: 0700 Not tainted (6.12.0-105.debug_vm2.el10.ppc64le+debug) [ 2.552899] MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002822 XER: 0000000a [ 2.552954] CFAR: c0000000008f03f0 IRQMASK: 0 [ 2.552954] GPR00: c0000000007eef30 c0000000622e7650 c000000002b1ac00 0000000000000001 [ 2.552954] GPR04: 0000000000000008 0000000000000000 c0000000007eef30 ffffffffffffffff [ 2.552954] GPR08: 00000000ffff00f5 0000000000000001 0000000000000048 0000000000004000 [ 2.552954] GPR12: 00000003fa440000 c000000017ffa300 c0000000051d9f80 ffffffffffffffdb [ 2.552954] GPR16: 0000000000000000 0000000000000008 000000000000000a 60000000000000e0 [ 2.552954] GPR20: 4080000000000000 c0000000113af038 00007fffcf130000 0000700000000000 [ 2.552954] GPR24: c000000062a6a000 0000000000000001 8000000062a68000 0000000000000001 [ 2.552954] GPR28: 000000000000000a c000000062ebc600 0000000000002000 c000000062ebc760 [ 2.553170] NIP [c0000000007eef3c] free_pud_range+0x8bc/0x8d0 [ 2.553185] LR [c0000000007eef30] free_pud_range+0x8b0/0x8d0 [ 2.553199] Call Trace: [ 2.553207] [c0000000622e7650] [c0000000007eef30] free_pud_range+0x8b0/0x8d0 (unreliable) [ 2.553229] [c0000000622e7750] [c0000000007f40b4] free_pgd_range+0x284/0x3b0 [ 2.553248] [c0000000622e7800] [c0000000007f4630] free_pgtables+0x450/0x570 [ 2.553274] [c0000000622e78e0] [c0000000008161c0] exit_mmap+0x250/0x650 [ 2.553292] [c0000000622e7a30] [c0000000001b95b8] __mmput+0x98/0x290 [ 2.558344] [c0000000622e7a80] [c0000000001d1018] exit_mm+0x118/0x1b0 [ 2.558361] [c0000000622e7ac0] [c0000000001d141c] do_exit+0x2ec/0x870 [ 2.558376] [c0000000622e7b60] [c0000000001d1ca8] do_group_exit+0x88/0x150 [ 2.558391] [c0000000622e7bb0] [c0000000001d1db8] sys_exit_group+0x48/0x50 [ 2.558407] [c0000000622e7be0] [c00000000003d810] system_call_exception+0x1e0/0x4c0 [ 2.558423] [c0000000622e7e50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec (...) [ 2.558892] ---[ end trace 0000000000000000 ]--- [ 2.559022] BUG: Bad rss-counter state mm:000000002267cc9e type:MM_ANONPAGES val:1 [ 2.559037] BUG: non-zero pgtables_bytes on freeing mm: -6144 Here the modprobe process ended up with an allocated mm_struct from the mm_struct slab that was used before by the debug_vm_pgtable test. That is not a problem, since the mm_stru ---truncated---

In the Linux kernel, the following vulnerability has been resolved: fs: writeback: fix use-after-free in __mark_inode_dirty() An use-after-free issue occurred when __mark_inode_dirty() get the bdi_writeback that was in the progress of switching. CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1 ...... pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __mark_inode_dirty+0x124/0x418 lr : __mark_inode_dirty+0x118/0x418 sp : ffffffc08c9dbbc0 ........ Call trace: __mark_inode_dirty+0x124/0x418 generic_update_time+0x4c/0x60 file_modified+0xcc/0xd0 ext4_buffered_write_iter+0x58/0x124 ext4_file_write_iter+0x54/0x704 vfs_write+0x1c0/0x308 ksys_write+0x74/0x10c __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x40/0xe4 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x194/0x198 Root cause is: systemd-random-seed kworker ---------------------------------------------------------------------- ___mark_inode_dirty inode_switch_wbs_work_fn spin_lock(&inode->i_lock); inode_attach_wb locked_inode_to_wb_and_lock_list get inode->i_wb spin_unlock(&inode->i_lock); spin_lock(&wb->list_lock) spin_lock(&inode->i_lock) inode_io_list_move_locked spin_unlock(&wb->list_lock) spin_unlock(&inode->i_lock) spin_lock(&old_wb->list_lock) inode_do_switch_wbs spin_lock(&inode->i_lock) inode->i_wb = new_wb spin_unlock(&inode->i_lock) spin_unlock(&old_wb->list_lock) wb_put_many(old_wb, nr_switched) cgwb_release old wb released wb_wakeup_delayed() accesses wb, then trigger the use-after-free issue Fix this race condition by holding inode spinlock until wb_wakeup_delayed() finished.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix dangling pointer in krb_authenticate krb_authenticate frees sess->user and does not set the pointer to NULL. It calls ksmbd_krb5_authenticate to reinitialise sess->user but that function may return without doing so. If that happens then smb2_sess_setup, which calls krb_authenticate, will be accessing free'd memory when it later uses sess->user.

A use-after-free flaw was found in D-Bus Development branch <= 1.13.16, dbus-1.12.x stable branch <= 1.12.18, and dbus-1.10.x and older branches <= 1.10.30 when a system has multiple usernames sharing the same UID. When a set of policy rules references these usernames, D-Bus may free some memory in the heap, which is still used by data structures necessary for the other usernames sharing the UID, possibly leading to a crash or other undefined behaviors

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix UAF in __close_file_table_ids A use-after-free is possible if one thread destroys the file via __ksmbd_close_fd while another thread holds a reference to it. The existing checks on fp->refcount are not sufficient to prevent this. The fix takes ft->lock around the section which removes the file from the file table. This prevents two threads acquiring the same file pointer via __close_file_table_ids, as well as the other functions which retrieve a file from the IDR and which already use this same lock.

A vulnerability was found in Linux Kernel where refcount leak in llcp_sock_bind() causing use-after-free which might lead to privilege escalations.

The sctp_do_peeloff function in net/sctp/socket.c in the Linux kernel before 4.14 does not check whether the intended netns is used in a peel-off action, which allows local users to cause a denial of service (use-after-free and system crash) or possibly have unspecified other impact via crafted system calls.

In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Remove the direct link to net_device The similar patch in siw is in the link: https://git.kernel.org/rdma/rdma/c/16b87037b48889 This problem also occurred in RXE. The following analyze this problem. In the following Call Traces: " BUG: KASAN: slab-use-after-free in dev_get_flags+0x188/0x1d0 net/core/dev.c:8782 Read of size 4 at addr ffff8880554640b0 by task kworker/1:4/5295 CPU: 1 UID: 0 PID: 5295 Comm: kworker/1:4 Not tainted 6.12.0-rc3-syzkaller-00399-g9197b73fd7bb #0 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: infiniband ib_cache_event_task 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:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 dev_get_flags+0x188/0x1d0 net/core/dev.c:8782 rxe_query_port+0x12d/0x260 drivers/infiniband/sw/rxe/rxe_verbs.c:60 __ib_query_port drivers/infiniband/core/device.c:2111 [inline] ib_query_port+0x168/0x7d0 drivers/infiniband/core/device.c:2143 ib_cache_update+0x1a9/0xb80 drivers/infiniband/core/cache.c:1494 ib_cache_event_task+0xf3/0x1e0 drivers/infiniband/core/cache.c:1568 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> " 1). In the link [1], " infiniband syz2: set down " This means that on 839.350575, the event ib_cache_event_task was sent andi queued in ib_wq. 2). In the link [1], " team0 (unregistering): Port device team_slave_0 removed " It indicates that before 843.251853, the net device should be freed. 3). In the link [1], " BUG: KASAN: slab-use-after-free in dev_get_flags+0x188/0x1d0 " This means that on 850.559070, this slab-use-after-free problem occurred. In all, on 839.350575, the event ib_cache_event_task was sent and queued in ib_wq, before 843.251853, the net device veth was freed. on 850.559070, this event was executed, and the mentioned freed net device was called. Thus, the above call trace occurred. [1] https://syzkaller.appspot.com/x/log.txt?x=12e7025f980000

In the Linux kernel, the following vulnerability has been resolved: binder: fix node UAF in binder_add_freeze_work() In binder_add_freeze_work() we iterate over the proc->nodes with the proc->inner_lock held. However, this lock is temporarily dropped in order to acquire the node->lock first (lock nesting order). This can race with binder_node_release() and trigger a use-after-free: ================================================================== BUG: KASAN: slab-use-after-free in _raw_spin_lock+0xe4/0x19c Write of size 4 at addr ffff53c04c29dd04 by task freeze/640 CPU: 5 UID: 0 PID: 640 Comm: freeze Not tainted 6.11.0-07343-ga727812a8d45 #17 Hardware name: linux,dummy-virt (DT) Call trace: _raw_spin_lock+0xe4/0x19c binder_add_freeze_work+0x148/0x478 binder_ioctl+0x1e70/0x25ac __arm64_sys_ioctl+0x124/0x190 Allocated by task 637: __kmalloc_cache_noprof+0x12c/0x27c binder_new_node+0x50/0x700 binder_transaction+0x35ac/0x6f74 binder_thread_write+0xfb8/0x42a0 binder_ioctl+0x18f0/0x25ac __arm64_sys_ioctl+0x124/0x190 Freed by task 637: kfree+0xf0/0x330 binder_thread_read+0x1e88/0x3a68 binder_ioctl+0x16d8/0x25ac __arm64_sys_ioctl+0x124/0x190 ================================================================== Fix the race by taking a temporary reference on the node before releasing the proc->inner lock. This ensures the node remains alive while in use.

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: nfsd: provide locking for v4_end_grace Writing to v4_end_grace can race with server shutdown and result in memory being accessed after it was freed - reclaim_str_hashtbl in particularly. We cannot hold nfsd_mutex across the nfsd4_end_grace() call as that is held while client_tracking_op->init() is called and that can wait for an upcall to nfsdcltrack which can write to v4_end_grace, resulting in a deadlock. nfsd4_end_grace() is also called by the landromat work queue and this doesn't require locking as server shutdown will stop the work and wait for it before freeing anything that nfsd4_end_grace() might access. However, we must be sure that writing to v4_end_grace doesn't restart the work item after shutdown has already waited for it. For this we add a new flag protected with nn->client_lock. It is set only while it is safe to make client tracking calls, and v4_end_grace only schedules work while the flag is set with the spinlock held. So this patch adds a nfsd_net field "client_tracking_active" which is set as described. Another field "grace_end_forced", is set when v4_end_grace is written. After this is set, and providing client_tracking_active is set, the laundromat is scheduled. This "grace_end_forced" field bypasses other checks for whether the grace period has finished. This resolves a race which can result in use-after-free.

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: 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: ublk: fix use-after-free in ublk_partition_scan_work A race condition exists between the async partition scan work and device teardown that can lead to a use-after-free of ub->ub_disk: 1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk() 2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does: - del_gendisk(ub->ub_disk) - ublk_detach_disk() sets ub->ub_disk = NULL - put_disk() which may free the disk 3. The worker ublk_partition_scan_work() then dereferences ub->ub_disk leading to UAF Fix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold a reference to the disk during the partition scan. The spinlock in ublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker either gets a valid reference or sees NULL and exits early. Also change flush_work() to cancel_work_sync() to avoid running the partition scan work unnecessarily when the disk is already detached.

A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation. When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: fix reference counting on zcrypt card objects Tests with hot-plugging crytpo cards on KVM guests with debug kernel build revealed an use after free for the load field of the struct zcrypt_card. The reason was an incorrect reference handling of the zcrypt card object which could lead to a free of the zcrypt card object while it was still in use. This is an example of the slab message: kernel: 0x00000000885a7512-0x00000000885a7513 @offset=1298. First byte 0x68 instead of 0x6b kernel: Allocated in zcrypt_card_alloc+0x36/0x70 [zcrypt] age=18046 cpu=3 pid=43 kernel: kmalloc_trace+0x3f2/0x470 kernel: zcrypt_card_alloc+0x36/0x70 [zcrypt] kernel: zcrypt_cex4_card_probe+0x26/0x380 [zcrypt_cex4] kernel: ap_device_probe+0x15c/0x290 kernel: really_probe+0xd2/0x468 kernel: driver_probe_device+0x40/0xf0 kernel: __device_attach_driver+0xc0/0x140 kernel: bus_for_each_drv+0x8c/0xd0 kernel: __device_attach+0x114/0x198 kernel: bus_probe_device+0xb4/0xc8 kernel: device_add+0x4d2/0x6e0 kernel: ap_scan_adapter+0x3d0/0x7c0 kernel: ap_scan_bus+0x5a/0x3b0 kernel: ap_scan_bus_wq_callback+0x40/0x60 kernel: process_one_work+0x26e/0x620 kernel: worker_thread+0x21c/0x440 kernel: Freed in zcrypt_card_put+0x54/0x80 [zcrypt] age=9024 cpu=3 pid=43 kernel: kfree+0x37e/0x418 kernel: zcrypt_card_put+0x54/0x80 [zcrypt] kernel: ap_device_remove+0x4c/0xe0 kernel: device_release_driver_internal+0x1c4/0x270 kernel: bus_remove_device+0x100/0x188 kernel: device_del+0x164/0x3c0 kernel: device_unregister+0x30/0x90 kernel: ap_scan_adapter+0xc8/0x7c0 kernel: ap_scan_bus+0x5a/0x3b0 kernel: ap_scan_bus_wq_callback+0x40/0x60 kernel: process_one_work+0x26e/0x620 kernel: worker_thread+0x21c/0x440 kernel: kthread+0x150/0x168 kernel: __ret_from_fork+0x3c/0x58 kernel: ret_from_fork+0xa/0x30 kernel: Slab 0x00000372022169c0 objects=20 used=18 fp=0x00000000885a7c88 flags=0x3ffff00000000a00(workingset|slab|node=0|zone=1|lastcpupid=0x1ffff) kernel: Object 0x00000000885a74b8 @offset=1208 fp=0x00000000885a7c88 kernel: Redzone 00000000885a74b0: bb bb bb bb bb bb bb bb ........ kernel: Object 00000000885a74b8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74c8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74d8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74e8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a74f8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk kernel: Object 00000000885a7508: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 68 4b 6b 6b 6b a5 kkkkkkkkkkhKkkk. kernel: Redzone 00000000885a7518: bb bb bb bb bb bb bb bb ........ kernel: Padding 00000000885a756c: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZ kernel: CPU: 0 PID: 387 Comm: systemd-udevd Not tainted 6.8.0-HF #2 kernel: Hardware name: IBM 3931 A01 704 (KVM/Linux) kernel: Call Trace: kernel: [<00000000ca5ab5b8>] dump_stack_lvl+0x90/0x120 kernel: [<00000000c99d78bc>] check_bytes_and_report+0x114/0x140 kernel: [<00000000c99d53cc>] check_object+0x334/0x3f8 kernel: [<00000000c99d820c>] alloc_debug_processing+0xc4/0x1f8 kernel: [<00000000c99d852e>] get_partial_node.part.0+0x1ee/0x3e0 kernel: [<00000000c99d94ec>] ___slab_alloc+0xaf4/0x13c8 kernel: [<00000000c99d9e38>] __slab_alloc.constprop.0+0x78/0xb8 kernel: [<00000000c99dc8dc>] __kmalloc+0x434/0x590 kernel: [<00000000c9b4c0ce>] ext4_htree_store_dirent+0x4e/0x1c0 kernel: [<00000000c9b908a2>] htree_dirblock_to_tree+0x17a/0x3f0 kernel: ---truncated---

In the Linux Kernel before versions 4.20.8 and 4.19.21 a use-after-free error in the "sctp_sendmsg()" function (net/sctp/socket.c) when handling SCTP_SENDALL flag can be exploited to corrupt memory.

The mq_notify function in the Linux kernel through 4.11.9 does not set the sock pointer to NULL upon entry into the retry logic. During a user-space close of a Netlink socket, it allows attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact.

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Sync IRQ works before buffer destruction If something was written to the buffer just before destruction, it may be possible (maybe not in a real system, but it did happen in ARCH=um with time-travel) to destroy the ringbuffer before the IRQ work ran, leading this KASAN report (or a crash without KASAN): BUG: KASAN: slab-use-after-free in irq_work_run_list+0x11a/0x13a Read of size 8 at addr 000000006d640a48 by task swapper/0 CPU: 0 PID: 0 Comm: swapper Tainted: G W O 6.3.0-rc1 #7 Stack: 60c4f20f 0c203d48 41b58ab3 60f224fc 600477fa 60f35687 60c4f20f 601273dd 00000008 6101eb00 6101eab0 615be548 Call Trace: [<60047a58>] show_stack+0x25e/0x282 [<60c609e0>] dump_stack_lvl+0x96/0xfd [<60c50d4c>] print_report+0x1a7/0x5a8 [<603078d3>] kasan_report+0xc1/0xe9 [<60308950>] __asan_report_load8_noabort+0x1b/0x1d [<60232844>] irq_work_run_list+0x11a/0x13a [<602328b4>] irq_work_tick+0x24/0x34 [<6017f9dc>] update_process_times+0x162/0x196 [<6019f335>] tick_sched_handle+0x1a4/0x1c3 [<6019fd9e>] tick_sched_timer+0x79/0x10c [<601812b9>] __hrtimer_run_queues.constprop.0+0x425/0x695 [<60182913>] hrtimer_interrupt+0x16c/0x2c4 [<600486a3>] um_timer+0x164/0x183 [...] Allocated by task 411: save_stack_trace+0x99/0xb5 stack_trace_save+0x81/0x9b kasan_save_stack+0x2d/0x54 kasan_set_track+0x34/0x3e kasan_save_alloc_info+0x25/0x28 ____kasan_kmalloc+0x8b/0x97 __kasan_kmalloc+0x10/0x12 __kmalloc+0xb2/0xe8 load_elf_phdrs+0xee/0x182 [...] The buggy address belongs to the object at 000000006d640800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 584 bytes inside of freed 1024-byte region [000000006d640800, 000000006d640c00) Add the appropriate irq_work_sync() so the work finishes before the buffers are destroyed. Prior to the commit in the Fixes tag below, there was only a single global IRQ work, so this issue didn't exist.

In the Linux kernel, the following vulnerability has been resolved: netfilter: allow exp not to be removed in nf_ct_find_expectation Currently nf_conntrack_in() calling nf_ct_find_expectation() will remove the exp from the hash table. However, in some scenario, we expect the exp not to be removed when the created ct will not be confirmed, like in OVS and TC conntrack in the following patches. This patch allows exp not to be removed by setting IPS_CONFIRMED in the status of the tmpl.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: fail SCO/ISO via hci_conn_failed if ACL gone early Not calling hci_(dis)connect_cfm before deleting conn referred to by a socket generally results to use-after-free. When cleaning up SCO connections when the parent ACL is deleted too early, use hci_conn_failed to do the connection cleanup properly. We also need to clean up ISO connections in a similar situation when connecting has started but LE Create CIS is not yet sent, so do it too here.

In the Linux kernel, the following vulnerability has been resolved: drivers/amd/pm: fix a use-after-free in kv_parse_power_table When ps allocated by kzalloc equals to NULL, kv_parse_power_table frees adev->pm.dpm.ps that allocated before. However, after the control flow goes through the following call chains: kv_parse_power_table |-> kv_dpm_init |-> kv_dpm_sw_init |-> kv_dpm_fini The adev->pm.dpm.ps is used in the for loop of kv_dpm_fini after its first free in kv_parse_power_table and causes a use-after-free bug.

In the Linux kernel, the following vulnerability has been resolved: scsi: scsi_debug: Sanity check block descriptor length in resp_mode_select() In resp_mode_select() sanity check the block descriptor len to avoid UAF. BUG: KASAN: use-after-free in resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509 Read of size 1 at addr ffff888026670f50 by task scsicmd/15032 CPU: 1 PID: 15032 Comm: scsicmd Not tainted 5.15.0-01d0625 #15 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Call Trace: <TASK> dump_stack_lvl+0x89/0xb5 lib/dump_stack.c:107 print_address_description.constprop.9+0x28/0x160 mm/kasan/report.c:257 kasan_report.cold.14+0x7d/0x117 mm/kasan/report.c:443 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 resp_mode_select+0xa4c/0xb40 drivers/scsi/scsi_debug.c:2509 schedule_resp+0x4af/0x1a10 drivers/scsi/scsi_debug.c:5483 scsi_debug_queuecommand+0x8c9/0x1e70 drivers/scsi/scsi_debug.c:7537 scsi_queue_rq+0x16b4/0x2d10 drivers/scsi/scsi_lib.c:1521 blk_mq_dispatch_rq_list+0xb9b/0x2700 block/blk-mq.c:1640 __blk_mq_sched_dispatch_requests+0x28f/0x590 block/blk-mq-sched.c:325 blk_mq_sched_dispatch_requests+0x105/0x190 block/blk-mq-sched.c:358 __blk_mq_run_hw_queue+0xe5/0x150 block/blk-mq.c:1762 __blk_mq_delay_run_hw_queue+0x4f8/0x5c0 block/blk-mq.c:1839 blk_mq_run_hw_queue+0x18d/0x350 block/blk-mq.c:1891 blk_mq_sched_insert_request+0x3db/0x4e0 block/blk-mq-sched.c:474 blk_execute_rq_nowait+0x16b/0x1c0 block/blk-exec.c:63 sg_common_write.isra.18+0xeb3/0x2000 drivers/scsi/sg.c:837 sg_new_write.isra.19+0x570/0x8c0 drivers/scsi/sg.c:775 sg_ioctl_common+0x14d6/0x2710 drivers/scsi/sg.c:941 sg_ioctl+0xa2/0x180 drivers/scsi/sg.c:1166 __x64_sys_ioctl+0x19d/0x220 fs/ioctl.c:52 do_syscall_64+0x3a/0x80 arch/x86/entry/common.c:50 entry_SYSCALL_64_after_hwframe+0x44/0xae arch/x86/entry/entry_64.S:113

Various refcounting bugs in the multi-BSS handling in the mac80211 stack in the Linux kernel 5.1 through 5.19.x before 5.19.16 could be used by local attackers (able to inject WLAN frames) to trigger use-after-free conditions to potentially execute code.

In the Linux kernel, the following vulnerability has been resolved: spi: Fix simplification of devm_spi_register_controller This reverts commit 59ebbe40fb51 ("spi: simplify devm_spi_register_controller"). If devm_add_action() fails in devm_add_action_or_reset(), devm_spi_unregister() will be called, it decreases the refcount of 'ctlr->dev' to 0, then it will cause uaf in the drivers that calling spi_put_controller() in error path.

In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: Cleanup CPU timers before freeing them during exec Commit 55e8c8eb2c7b ("posix-cpu-timers: Store a reference to a pid not a task") started looking up tasks by PID when deleting a CPU timer. When a non-leader thread calls execve, it will switch PIDs with the leader process. Then, as it calls exit_itimers, posix_cpu_timer_del cannot find the task because the timer still points out to the old PID. That means that armed timers won't be disarmed, that is, they won't be removed from the timerqueue_list. exit_itimers will still release their memory, and when that list is later processed, it leads to a use-after-free. Clean up the timers from the de-threaded task before freeing them. This prevents a reported use-after-free.

An issue was discovered in the Linux kernel before 5.0.19. The XFRM subsystem has a use-after-free, related to an xfrm_state_fini panic, aka CID-dbb2483b2a46.

A use-after-free flaw was found in the Linux kernel’s Netfilter functionality when adding a rule with NFTA_RULE_CHAIN_ID. This flaw allows a local user to crash or escalate their privileges on the system.

In the Linux kernel, the following vulnerability has been resolved: mtd: core: add missing of_node_get() in dynamic partitions code This fixes unbalanced of_node_put(): [ 1.078910] 6 cmdlinepart partitions found on MTD device gpmi-nand [ 1.085116] Creating 6 MTD partitions on "gpmi-nand": [ 1.090181] 0x000000000000-0x000008000000 : "nandboot" [ 1.096952] 0x000008000000-0x000009000000 : "nandfit" [ 1.103547] 0x000009000000-0x00000b000000 : "nandkernel" [ 1.110317] 0x00000b000000-0x00000c000000 : "nanddtb" [ 1.115525] ------------[ cut here ]------------ [ 1.120141] refcount_t: addition on 0; use-after-free. [ 1.125328] WARNING: CPU: 0 PID: 1 at lib/refcount.c:25 refcount_warn_saturate+0xdc/0x148 [ 1.133528] Modules linked in: [ 1.136589] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc7-next-20220930-04543-g8cf3f7 [ 1.146342] Hardware name: Freescale i.MX8DXL DDR3L EVK (DT) [ 1.151999] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 1.158965] pc : refcount_warn_saturate+0xdc/0x148 [ 1.163760] lr : refcount_warn_saturate+0xdc/0x148 [ 1.168556] sp : ffff800009ddb080 [ 1.171866] x29: ffff800009ddb080 x28: ffff800009ddb35a x27: 0000000000000002 [ 1.179015] x26: ffff8000098b06ad x25: ffffffffffffffff x24: ffff0a00ffffff05 [ 1.186165] x23: ffff00001fdf6470 x22: ffff800009ddb367 x21: 0000000000000000 [ 1.193314] x20: ffff00001fdfebe8 x19: ffff00001fdfec50 x18: ffffffffffffffff [ 1.200464] x17: 0000000000000000 x16: 0000000000000118 x15: 0000000000000004 [ 1.207614] x14: 0000000000000fff x13: ffff800009bca248 x12: 0000000000000003 [ 1.214764] x11: 00000000ffffefff x10: c0000000ffffefff x9 : 4762cb2ccb52de00 [ 1.221914] x8 : 4762cb2ccb52de00 x7 : 205d313431303231 x6 : 312e31202020205b [ 1.229063] x5 : ffff800009d55c1f x4 : 0000000000000001 x3 : 0000000000000000 [ 1.236213] x2 : 0000000000000000 x1 : ffff800009954be6 x0 : 000000000000002a [ 1.243365] Call trace: [ 1.245806] refcount_warn_saturate+0xdc/0x148 [ 1.250253] kobject_get+0x98/0x9c [ 1.253658] of_node_get+0x20/0x34 [ 1.257072] of_fwnode_get+0x3c/0x54 [ 1.260652] fwnode_get_nth_parent+0xd8/0xf4 [ 1.264926] fwnode_full_name_string+0x3c/0xb4 [ 1.269373] device_node_string+0x498/0x5b4 [ 1.273561] pointer+0x41c/0x5d0 [ 1.276793] vsnprintf+0x4d8/0x694 [ 1.280198] vprintk_store+0x164/0x528 [ 1.283951] vprintk_emit+0x98/0x164 [ 1.287530] vprintk_default+0x44/0x6c [ 1.291284] vprintk+0xf0/0x134 [ 1.294428] _printk+0x54/0x7c [ 1.297486] of_node_release+0xe8/0x128 [ 1.301326] kobject_put+0x98/0xfc [ 1.304732] of_node_put+0x1c/0x28 [ 1.308137] add_mtd_device+0x484/0x6d4 [ 1.311977] add_mtd_partitions+0xf0/0x1d0 [ 1.316078] parse_mtd_partitions+0x45c/0x518 [ 1.320439] mtd_device_parse_register+0xb0/0x274 [ 1.325147] gpmi_nand_probe+0x51c/0x650 [ 1.329074] platform_probe+0xa8/0xd0 [ 1.332740] really_probe+0x130/0x334 [ 1.336406] __driver_probe_device+0xb4/0xe0 [ 1.340681] driver_probe_device+0x3c/0x1f8 [ 1.344869] __driver_attach+0xdc/0x1a4 [ 1.348708] bus_for_each_dev+0x80/0xcc [ 1.352548] driver_attach+0x24/0x30 [ 1.356127] bus_add_driver+0x108/0x1f4 [ 1.359967] driver_register+0x78/0x114 [ 1.363807] __platform_driver_register+0x24/0x30 [ 1.368515] gpmi_nand_driver_init+0x1c/0x28 [ 1.372798] do_one_initcall+0xbc/0x238 [ 1.376638] do_initcall_level+0x94/0xb4 [ 1.380565] do_initcalls+0x54/0x94 [ 1.384058] do_basic_setup+0x1c/0x28 [ 1.387724] kernel_init_freeable+0x110/0x188 [ 1.392084] kernel_init+0x20/0x1a0 [ 1.395578] ret_from_fork+0x10/0x20 [ 1.399157] ---[ end trace 0000000000000000 ]--- [ 1.403782] ------------[ cut here ]------------

A use-after-free flaw was found in the Linux kernel's netfilter in the way a user triggers the nft_pipapo_remove function with the element, without a NFT_SET_EXT_KEY_END. This issue could allow a local user to crash the system or potentially escalate their privileges on the system.

In the Linux kernel, the following vulnerability has been resolved: firmware_loader: Fix use-after-free during unregister In the following code within firmware_upload_unregister(), the call to device_unregister() could result in the dev_release function freeing the fw_upload_priv structure before it is dereferenced for the call to module_put(). This bug was found by the kernel test robot using CONFIG_KASAN while running the firmware selftests. device_unregister(&fw_sysfs->dev); module_put(fw_upload_priv->module); The problem is fixed by copying fw_upload_priv->module to a local variable for use when calling device_unregister().

In the Linux kernel, the following vulnerability has been resolved: btrfs: always report error in run_one_delayed_ref() Currently we have a btrfs_debug() for run_one_delayed_ref() failure, but if end users hit such problem, there will be no chance that btrfs_debug() is enabled. This can lead to very little useful info for debugging. This patch will: - Add extra info for error reporting Including: * logical bytenr * num_bytes * type * action * ref_mod - Replace the btrfs_debug() with btrfs_err() - Move the error reporting into run_one_delayed_ref() This is to avoid use-after-free, the @node can be freed in the caller. This error should only be triggered at most once. As if run_one_delayed_ref() failed, we trigger the error message, then causing the call chain to error out: btrfs_run_delayed_refs() `- btrfs_run_delayed_refs() `- btrfs_run_delayed_refs_for_head() `- run_one_delayed_ref() And we will abort the current transaction in btrfs_run_delayed_refs(). If we have to run delayed refs for the abort transaction, run_one_delayed_ref() will just cleanup the refs and do nothing, thus no new error messages would be output.

In the Linux kernel, the following vulnerability has been resolved: s390/qeth: fix use-after-free in hsci KASAN found that addr was dereferenced after br2dev_event_work was freed. ================================================================== BUG: KASAN: use-after-free in qeth_l2_br2dev_worker+0x5ba/0x6b0 Read of size 1 at addr 00000000fdcea440 by task kworker/u760:4/540 CPU: 17 PID: 540 Comm: kworker/u760:4 Tainted: G E 6.1.0-20221128.rc7.git1.5aa3bed4ce83.300.fc36.s390x+kasan #1 Hardware name: IBM 8561 T01 703 (LPAR) Workqueue: 0.0.8000_event qeth_l2_br2dev_worker Call Trace: [<000000016944d4ce>] dump_stack_lvl+0xc6/0xf8 [<000000016942cd9c>] print_address_description.constprop.0+0x34/0x2a0 [<000000016942d118>] print_report+0x110/0x1f8 [<0000000167a7bd04>] kasan_report+0xfc/0x128 [<000000016938d79a>] qeth_l2_br2dev_worker+0x5ba/0x6b0 [<00000001673edd1e>] process_one_work+0x76e/0x1128 [<00000001673ee85c>] worker_thread+0x184/0x1098 [<000000016740718a>] kthread+0x26a/0x310 [<00000001672c606a>] __ret_from_fork+0x8a/0xe8 [<00000001694711da>] ret_from_fork+0xa/0x40 Allocated by task 108338: kasan_save_stack+0x40/0x68 kasan_set_track+0x36/0x48 __kasan_kmalloc+0xa0/0xc0 qeth_l2_switchdev_event+0x25a/0x738 atomic_notifier_call_chain+0x9c/0xf8 br_switchdev_fdb_notify+0xf4/0x110 fdb_notify+0x122/0x180 fdb_add_entry.constprop.0.isra.0+0x312/0x558 br_fdb_add+0x59e/0x858 rtnl_fdb_add+0x58a/0x928 rtnetlink_rcv_msg+0x5f8/0x8d8 netlink_rcv_skb+0x1f2/0x408 netlink_unicast+0x570/0x790 netlink_sendmsg+0x752/0xbe0 sock_sendmsg+0xca/0x110 ____sys_sendmsg+0x510/0x6a8 ___sys_sendmsg+0x12a/0x180 __sys_sendmsg+0xe6/0x168 __do_sys_socketcall+0x3c8/0x468 do_syscall+0x22c/0x328 __do_syscall+0x94/0xf0 system_call+0x82/0xb0 Freed by task 540: kasan_save_stack+0x40/0x68 kasan_set_track+0x36/0x48 kasan_save_free_info+0x4c/0x68 ____kasan_slab_free+0x14e/0x1a8 __kasan_slab_free+0x24/0x30 __kmem_cache_free+0x168/0x338 qeth_l2_br2dev_worker+0x154/0x6b0 process_one_work+0x76e/0x1128 worker_thread+0x184/0x1098 kthread+0x26a/0x310 __ret_from_fork+0x8a/0xe8 ret_from_fork+0xa/0x40 Last potentially related work creation: kasan_save_stack+0x40/0x68 __kasan_record_aux_stack+0xbe/0xd0 insert_work+0x56/0x2e8 __queue_work+0x4ce/0xd10 queue_work_on+0xf4/0x100 qeth_l2_switchdev_event+0x520/0x738 atomic_notifier_call_chain+0x9c/0xf8 br_switchdev_fdb_notify+0xf4/0x110 fdb_notify+0x122/0x180 fdb_add_entry.constprop.0.isra.0+0x312/0x558 br_fdb_add+0x59e/0x858 rtnl_fdb_add+0x58a/0x928 rtnetlink_rcv_msg+0x5f8/0x8d8 netlink_rcv_skb+0x1f2/0x408 netlink_unicast+0x570/0x790 netlink_sendmsg+0x752/0xbe0 sock_sendmsg+0xca/0x110 ____sys_sendmsg+0x510/0x6a8 ___sys_sendmsg+0x12a/0x180 __sys_sendmsg+0xe6/0x168 __do_sys_socketcall+0x3c8/0x468 do_syscall+0x22c/0x328 __do_syscall+0x94/0xf0 system_call+0x82/0xb0 Second to last potentially related work creation: kasan_save_stack+0x40/0x68 __kasan_record_aux_stack+0xbe/0xd0 kvfree_call_rcu+0xb2/0x760 kernfs_unlink_open_file+0x348/0x430 kernfs_fop_release+0xc2/0x320 __fput+0x1ae/0x768 task_work_run+0x1bc/0x298 exit_to_user_mode_prepare+0x1a0/0x1a8 __do_syscall+0x94/0xf0 system_call+0x82/0xb0 The buggy address belongs to the object at 00000000fdcea400 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 64 bytes inside of 96-byte region [00000000fdcea400, 00000000fdcea460) The buggy address belongs to the physical page: page:000000005a9c26e8 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xfdcea flags: 0x3ffff00000000200(slab|node=0|zone=1|lastcpupid=0x1ffff) raw: 3ffff00000000200 0000000000000000 0000000100000122 000000008008cc00 raw: 0000000000000000 0020004100000000 ffffffff00000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: 00000000fdcea300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc 00000000fdcea380: fb fb fb fb fb fb f ---truncated---

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix use-after-free during gpu recovery [Why] [ 754.862560] refcount_t: underflow; use-after-free. [ 754.862898] Call Trace: [ 754.862903] <TASK> [ 754.862913] amdgpu_job_free_cb+0xc2/0xe1 [amdgpu] [ 754.863543] drm_sched_main.cold+0x34/0x39 [amd_sched] [How] The fw_fence may be not init, check whether dma_fence_init is performed before job free

In the Linux kernel, the following vulnerability has been resolved: drm/vc4: kms: Clear the HVS FIFO commit pointer once done Commit 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") introduced a wait on the previous commit done on a given HVS FIFO. However, we never cleared that pointer once done. Since drm_crtc_commit_put can free the drm_crtc_commit structure directly if we were the last user, this means that it can lead to a use-after free if we were to duplicate the state, and that stale pointer would even be copied to the new state. Set the pointer to NULL once we're done with the wait so that we don't carry over a pointer to a free'd structure.

A use-after-free flaw was found in Linux kernel before 5.19.2. This issue occurs in cmd_hdl_filter in drivers/staging/rtl8712/rtl8712_cmd.c, allowing an attacker to launch a local denial of service attack and gain escalation of privileges.

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Fix "KASAN: slab-use-after-free Read in ib_register_device" problem Call Trace: __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:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 strlen+0x93/0xa0 lib/string.c:420 __fortify_strlen include/linux/fortify-string.h:268 [inline] get_kobj_path_length lib/kobject.c:118 [inline] kobject_get_path+0x3f/0x2a0 lib/kobject.c:158 kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545 ib_register_device drivers/infiniband/core/device.c:1472 [inline] ib_register_device+0x8cf/0xe00 drivers/infiniband/core/device.c:1393 rxe_register_device+0x275/0x320 drivers/infiniband/sw/rxe/rxe_verbs.c:1552 rxe_net_add+0x8e/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:550 rxe_newlink+0x70/0x190 drivers/infiniband/sw/rxe/rxe.c:225 nldev_newlink+0x3a3/0x680 drivers/infiniband/core/nldev.c:1796 rdma_nl_rcv_msg+0x387/0x6e0 drivers/infiniband/core/netlink.c:195 rdma_nl_rcv_skb.constprop.0.isra.0+0x2e5/0x450 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2566 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2620 __sys_sendmsg+0x16d/0x220 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f This problem is similar to the problem that the commit 1d6a9e7449e2 ("RDMA/core: Fix use-after-free when rename device name") fixes. The root cause is: the function ib_device_rename() renames the name with lock. But in the function kobject_uevent(), this name is accessed without lock protection at the same time. The solution is to add the lock protection when this name is accessed in the function kobject_uevent().

In the Linux kernel, the following vulnerability has been resolved: cdx: Fix possible UAF error in driver_override_show() Fixed a possible UAF problem in driver_override_show() in drivers/cdx/cdx.c This function driver_override_show() is part of DEVICE_ATTR_RW, which includes both driver_override_show() and driver_override_store(). These functions can be executed concurrently in sysfs. The driver_override_store() function uses driver_set_override() to update the driver_override value, and driver_set_override() internally locks the device (device_lock(dev)). If driver_override_show() reads cdx_dev->driver_override without locking, it could potentially access a freed pointer if driver_override_store() frees the string concurrently. This could lead to printing a kernel address, which is a security risk since DEVICE_ATTR can be read by all users. Additionally, a similar pattern is used in drivers/amba/bus.c, as well as many other bus drivers, where device_lock() is taken in the show function, and it has been working without issues. This potential bug was detected by our experimental static analysis tool, which analyzes locking APIs and paired functions to identify data races and atomicity violations.

Race condition in the snd_pcm_period_elapsed function in sound/core/pcm_lib.c in the ALSA subsystem in the Linux kernel before 4.7 allows local users to cause a denial of service (use-after-free) or possibly have unspecified other impact via a crafted SNDRV_PCM_TRIGGER_START command.

In the Linux kernel, the following vulnerability has been resolved: ext4: fix use-after-free in ext4_rename_dir_prepare We got issue as follows: EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue ext4_get_first_dir_block: bh->b_data=0xffff88810bee6000 len=34478 ext4_get_first_dir_block: *parent_de=0xffff88810beee6ae bh->b_data=0xffff88810bee6000 ext4_rename_dir_prepare: [1] parent_de=0xffff88810beee6ae ================================================================== BUG: KASAN: use-after-free in ext4_rename_dir_prepare+0x152/0x220 Read of size 4 at addr ffff88810beee6ae by task rep/1895 CPU: 13 PID: 1895 Comm: rep Not tainted 5.10.0+ #241 Call Trace: dump_stack+0xbe/0xf9 print_address_description.constprop.0+0x1e/0x220 kasan_report.cold+0x37/0x7f ext4_rename_dir_prepare+0x152/0x220 ext4_rename+0xf44/0x1ad0 ext4_rename2+0x11c/0x170 vfs_rename+0xa84/0x1440 do_renameat2+0x683/0x8f0 __x64_sys_renameat+0x53/0x60 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f45a6fc41c9 RSP: 002b:00007ffc5a470218 EFLAGS: 00000246 ORIG_RAX: 0000000000000108 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f45a6fc41c9 RDX: 0000000000000005 RSI: 0000000020000180 RDI: 0000000000000005 RBP: 00007ffc5a470240 R08: 00007ffc5a470160 R09: 0000000020000080 R10: 00000000200001c0 R11: 0000000000000246 R12: 0000000000400bb0 R13: 00007ffc5a470320 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the page: page:00000000440015ce refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x10beee flags: 0x200000000000000() raw: 0200000000000000 ffffea00043ff4c8 ffffea0004325608 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88810beee580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88810beee600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88810beee680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88810beee700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88810beee780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== Disabling lock debugging due to kernel taint ext4_rename_dir_prepare: [2] parent_de->inode=3537895424 ext4_rename_dir_prepare: [3] dir=0xffff888124170140 ext4_rename_dir_prepare: [4] ino=2 ext4_rename_dir_prepare: ent->dir->i_ino=2 parent=-757071872 Reason is first directory entry which 'rec_len' is 34478, then will get illegal parent entry. Now, we do not check directory entry after read directory block in 'ext4_get_first_dir_block'. To solve this issue, check directory entry in 'ext4_get_first_dir_block'. [ Trigger an ext4_error() instead of just warning if the directory is missing a '.' or '..' entry. Also make sure we return an error code if the file system is corrupted. -TYT ]