A NULL pointer dereference flaw was found in the Linux kernel’s X.25 set of standardized network protocols functionality in the way a user terminates their session using a simulated Ethernet card and continued usage of this connection. This flaw allows a local user to crash the system.

A use-after-free vulnerability was found in the Linux kernel in drivers/net/hamradio. This flaw allows a local attacker with a user privilege to cause a denial of service (DOS) when the mkiss or sixpack device is detached and reclaim resources early.

In the Linux kernel, the following vulnerability has been resolved: ipmi: Fix UAF when uninstall ipmi_si and ipmi_msghandler module Hi, When testing install and uninstall of ipmi_si.ko and ipmi_msghandler.ko, the system crashed. The log as follows: [ 141.087026] BUG: unable to handle kernel paging request at ffffffffc09b3a5a [ 141.087241] PGD 8fe4c0d067 P4D 8fe4c0d067 PUD 8fe4c0f067 PMD 103ad89067 PTE 0 [ 141.087464] Oops: 0010 [#1] SMP NOPTI [ 141.087580] CPU: 67 PID: 668 Comm: kworker/67:1 Kdump: loaded Not tainted 4.18.0.x86_64 #47 [ 141.088009] Workqueue: events 0xffffffffc09b3a40 [ 141.088009] RIP: 0010:0xffffffffc09b3a5a [ 141.088009] Code: Bad RIP value. [ 141.088009] RSP: 0018:ffffb9094e2c3e88 EFLAGS: 00010246 [ 141.088009] RAX: 0000000000000000 RBX: ffff9abfdb1f04a0 RCX: 0000000000000000 [ 141.088009] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246 [ 141.088009] RBP: 0000000000000000 R08: ffff9abfffee3cb8 R09: 00000000000002e1 [ 141.088009] R10: ffffb9094cb73d90 R11: 00000000000f4240 R12: ffff9abfffee8700 [ 141.088009] R13: 0000000000000000 R14: ffff9abfdb1f04a0 R15: ffff9abfdb1f04a8 [ 141.088009] FS: 0000000000000000(0000) GS:ffff9abfffec0000(0000) knlGS:0000000000000000 [ 141.088009] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 141.088009] CR2: ffffffffc09b3a30 CR3: 0000008fe4c0a001 CR4: 00000000007606e0 [ 141.088009] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 141.088009] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 141.088009] PKRU: 55555554 [ 141.088009] Call Trace: [ 141.088009] ? process_one_work+0x195/0x390 [ 141.088009] ? worker_thread+0x30/0x390 [ 141.088009] ? process_one_work+0x390/0x390 [ 141.088009] ? kthread+0x10d/0x130 [ 141.088009] ? kthread_flush_work_fn+0x10/0x10 [ 141.088009] ? ret_from_fork+0x35/0x40] BUG: unable to handle kernel paging request at ffffffffc0b28a5a [ 200.223240] PGD 97fe00d067 P4D 97fe00d067 PUD 97fe00f067 PMD a580cbf067 PTE 0 [ 200.223464] Oops: 0010 [#1] SMP NOPTI [ 200.223579] CPU: 63 PID: 664 Comm: kworker/63:1 Kdump: loaded Not tainted 4.18.0.x86_64 #46 [ 200.224008] Workqueue: events 0xffffffffc0b28a40 [ 200.224008] RIP: 0010:0xffffffffc0b28a5a [ 200.224008] Code: Bad RIP value. [ 200.224008] RSP: 0018:ffffbf3c8e2a3e88 EFLAGS: 00010246 [ 200.224008] RAX: 0000000000000000 RBX: ffffa0799ad6bca0 RCX: 0000000000000000 [ 200.224008] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 0000000000000246 [ 200.224008] RBP: 0000000000000000 R08: ffff9fe43fde3cb8 R09: 00000000000000d5 [ 200.224008] R10: ffffbf3c8cb53d90 R11: 00000000000f4240 R12: ffff9fe43fde8700 [ 200.224008] R13: 0000000000000000 R14: ffffa0799ad6bca0 R15: ffffa0799ad6bca8 [ 200.224008] FS: 0000000000000000(0000) GS:ffff9fe43fdc0000(0000) knlGS:0000000000000000 [ 200.224008] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 200.224008] CR2: ffffffffc0b28a30 CR3: 00000097fe00a002 CR4: 00000000007606e0 [ 200.224008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 200.224008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 200.224008] PKRU: 55555554 [ 200.224008] Call Trace: [ 200.224008] ? process_one_work+0x195/0x390 [ 200.224008] ? worker_thread+0x30/0x390 [ 200.224008] ? process_one_work+0x390/0x390 [ 200.224008] ? kthread+0x10d/0x130 [ 200.224008] ? kthread_flush_work_fn+0x10/0x10 [ 200.224008] ? ret_from_fork+0x35/0x40 [ 200.224008] kernel fault(0x1) notification starting on CPU 63 [ 200.224008] kernel fault(0x1) notification finished on CPU 63 [ 200.224008] CR2: ffffffffc0b28a5a [ 200.224008] ---[ end trace c82a412d93f57412 ]--- The reason is as follows: T1: rmmod ipmi_si. ->ipmi_unregister_smi() -> ipmi_bmc_unregister() -> __ipmi_bmc_unregister() -> kref_put(&bmc->usecount, cleanup_bmc_device); -> schedule_work(&bmc->remove_work); T2: rmmod ipmi_msghandl ---truncated---

In the Linux kernel, the following vulnerability has been resolved: sched/fair: Prevent dead task groups from regaining cfs_rq's Kevin is reporting crashes which point to a use-after-free of a cfs_rq in update_blocked_averages(). Initial debugging revealed that we've live cfs_rq's (on_list=1) in an about to be kfree()'d task group in free_fair_sched_group(). However, it was unclear how that can happen. His kernel config happened to lead to a layout of struct sched_entity that put the 'my_q' member directly into the middle of the object which makes it incidentally overlap with SLUB's freelist pointer. That, in combination with SLAB_FREELIST_HARDENED's freelist pointer mangling, leads to a reliable access violation in form of a #GP which made the UAF fail fast. Michal seems to have run into the same issue[1]. He already correctly diagnosed that commit a7b359fc6a37 ("sched/fair: Correctly insert cfs_rq's to list on unthrottle") is causing the preconditions for the UAF to happen by re-adding cfs_rq's also to task groups that have no more running tasks, i.e. also to dead ones. His analysis, however, misses the real root cause and it cannot be seen from the crash backtrace only, as the real offender is tg_unthrottle_up() getting called via sched_cfs_period_timer() via the timer interrupt at an inconvenient time. When unregister_fair_sched_group() unlinks all cfs_rq's from the dying task group, it doesn't protect itself from getting interrupted. If the timer interrupt triggers while we iterate over all CPUs or after unregister_fair_sched_group() has finished but prior to unlinking the task group, sched_cfs_period_timer() will execute and walk the list of task groups, trying to unthrottle cfs_rq's, i.e. re-add them to the dying task group. These will later -- in free_fair_sched_group() -- be kfree()'ed while still being linked, leading to the fireworks Kevin and Michal are seeing. To fix this race, ensure the dying task group gets unlinked first. However, simply switching the order of unregistering and unlinking the task group isn't sufficient, as concurrent RCU walkers might still see it, as can be seen below: CPU1: CPU2: : timer IRQ: : do_sched_cfs_period_timer(): : : : distribute_cfs_runtime(): : rcu_read_lock(); : : : unthrottle_cfs_rq(): sched_offline_group(): : : walk_tg_tree_from(…,tg_unthrottle_up,…): list_del_rcu(&tg->list); : (1) : list_for_each_entry_rcu(child, &parent->children, siblings) : : (2) list_del_rcu(&tg->siblings); : : tg_unthrottle_up(): unregister_fair_sched_group(): struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)]; : : list_del_leaf_cfs_rq(tg->cfs_rq[cpu]); : : : : if (!cfs_rq_is_decayed(cfs_rq) || cfs_rq->nr_running) (3) : list_add_leaf_cfs_rq(cfs_rq); : : : : : : : : : ---truncated---

In the Linux kernel, the following vulnerability has been resolved: userfaultfd: release page in error path to avoid BUG_ON Consider the following sequence of events: 1. Userspace issues a UFFD ioctl, which ends up calling into shmem_mfill_atomic_pte(). We successfully account the blocks, we shmem_alloc_page(), but then the copy_from_user() fails. We return -ENOENT. We don't release the page we allocated. 2. Our caller detects this error code, tries the copy_from_user() after dropping the mmap_lock, and retries, calling back into shmem_mfill_atomic_pte(). 3. Meanwhile, let's say another process filled up the tmpfs being used. 4. So shmem_mfill_atomic_pte() fails to account blocks this time, and immediately returns - without releasing the page. This triggers a BUG_ON in our caller, which asserts that the page should always be consumed, unless -ENOENT is returned. To fix this, detect if we have such a "dangling" page when accounting fails, and if so, release it before returning.

In the Linux kernel, the following vulnerability has been resolved: btrfs: abort in rename_exchange if we fail to insert the second ref Error injection stress uncovered a problem where we'd leave a dangling inode ref if we failed during a rename_exchange. This happens because we insert the inode ref for one side of the rename, and then for the other side. If this second inode ref insert fails we'll leave the first one dangling and leave a corrupt file system behind. Fix this by aborting if we did the insert for the first inode ref.

In the Linux kernel, the following vulnerability has been resolved: xdp, net: Fix use-after-free in bpf_xdp_link_release The problem occurs between dev_get_by_index() and dev_xdp_attach_link(). At this point, dev_xdp_uninstall() is called. Then xdp link will not be detached automatically when dev is released. But link->dev already points to dev, when xdp link is released, dev will still be accessed, but dev has been released. dev_get_by_index() | link->dev = dev | | rtnl_lock() | unregister_netdevice_many() | dev_xdp_uninstall() | rtnl_unlock() rtnl_lock(); | dev_xdp_attach_link() | rtnl_unlock(); | | netdev_run_todo() // dev released bpf_xdp_link_release() | /* access dev. | use-after-free */ | [ 45.966867] BUG: KASAN: use-after-free in bpf_xdp_link_release+0x3b8/0x3d0 [ 45.967619] Read of size 8 at addr ffff00000f9980c8 by task a.out/732 [ 45.968297] [ 45.968502] CPU: 1 PID: 732 Comm: a.out Not tainted 5.13.0+ #22 [ 45.969222] Hardware name: linux,dummy-virt (DT) [ 45.969795] Call trace: [ 45.970106] dump_backtrace+0x0/0x4c8 [ 45.970564] show_stack+0x30/0x40 [ 45.970981] dump_stack_lvl+0x120/0x18c [ 45.971470] print_address_description.constprop.0+0x74/0x30c [ 45.972182] kasan_report+0x1e8/0x200 [ 45.972659] __asan_report_load8_noabort+0x2c/0x50 [ 45.973273] bpf_xdp_link_release+0x3b8/0x3d0 [ 45.973834] bpf_link_free+0xd0/0x188 [ 45.974315] bpf_link_put+0x1d0/0x218 [ 45.974790] bpf_link_release+0x3c/0x58 [ 45.975291] __fput+0x20c/0x7e8 [ 45.975706] ____fput+0x24/0x30 [ 45.976117] task_work_run+0x104/0x258 [ 45.976609] do_notify_resume+0x894/0xaf8 [ 45.977121] work_pending+0xc/0x328 [ 45.977575] [ 45.977775] The buggy address belongs to the page: [ 45.978369] page:fffffc00003e6600 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4f998 [ 45.979522] flags: 0x7fffe0000000000(node=0|zone=0|lastcpupid=0x3ffff) [ 45.980349] raw: 07fffe0000000000 fffffc00003e6708 ffff0000dac3c010 0000000000000000 [ 45.981309] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 45.982259] page dumped because: kasan: bad access detected [ 45.982948] [ 45.983153] Memory state around the buggy address: [ 45.983753] ffff00000f997f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 45.984645] ffff00000f998000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.985533] >ffff00000f998080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.986419] ^ [ 45.987112] ffff00000f998100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.988006] ffff00000f998180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 45.988895] ================================================================== [ 45.989773] Disabling lock debugging due to kernel taint [ 45.990552] Kernel panic - not syncing: panic_on_warn set ... [ 45.991166] CPU: 1 PID: 732 Comm: a.out Tainted: G B 5.13.0+ #22 [ 45.991929] Hardware name: linux,dummy-virt (DT) [ 45.992448] Call trace: [ 45.992753] dump_backtrace+0x0/0x4c8 [ 45.993208] show_stack+0x30/0x40 [ 45.993627] dump_stack_lvl+0x120/0x18c [ 45.994113] dump_stack+0x1c/0x34 [ 45.994530] panic+0x3a4/0x7d8 [ 45.994930] end_report+0x194/0x198 [ 45.995380] kasan_report+0x134/0x200 [ 45.995850] __asan_report_load8_noabort+0x2c/0x50 [ 45.996453] bpf_xdp_link_release+0x3b8/0x3d0 [ 45.997007] bpf_link_free+0xd0/0x188 [ 45.997474] bpf_link_put+0x1d0/0x218 [ 45.997942] bpf_link_release+0x3c/0x58 [ 45.998429] __fput+0x20c/0x7e8 [ 45.998833] ____fput+0x24/0x30 [ 45.999247] task_work_run+0x104/0x258 [ 45.999731] do_notify_resume+0x894/0xaf8 [ 46.000236] work_pending ---truncated---

In the Linux kernel, the following vulnerability has been resolved: tipc: skb_linearize the head skb when reassembling msgs It's not a good idea to append the frag skb to a skb's frag_list if the frag_list already has skbs from elsewhere, such as this skb was created by pskb_copy() where the frag_list was cloned (all the skbs in it were skb_get'ed) and shared by multiple skbs. However, the new appended frag skb should have been only seen by the current skb. Otherwise, it will cause use after free crashes as this appended frag skb are seen by multiple skbs but it only got skb_get called once. The same thing happens with a skb updated by pskb_may_pull() with a skb_cloned skb. Li Shuang has reported quite a few crashes caused by this when doing testing over macvlan devices: [] kernel BUG at net/core/skbuff.c:1970! [] Call Trace: [] skb_clone+0x4d/0xb0 [] macvlan_broadcast+0xd8/0x160 [macvlan] [] macvlan_process_broadcast+0x148/0x150 [macvlan] [] process_one_work+0x1a7/0x360 [] worker_thread+0x30/0x390 [] kernel BUG at mm/usercopy.c:102! [] Call Trace: [] __check_heap_object+0xd3/0x100 [] __check_object_size+0xff/0x16b [] simple_copy_to_iter+0x1c/0x30 [] __skb_datagram_iter+0x7d/0x310 [] __skb_datagram_iter+0x2a5/0x310 [] skb_copy_datagram_iter+0x3b/0x90 [] tipc_recvmsg+0x14a/0x3a0 [tipc] [] ____sys_recvmsg+0x91/0x150 [] ___sys_recvmsg+0x7b/0xc0 [] kernel BUG at mm/slub.c:305! [] Call Trace: [] <IRQ> [] kmem_cache_free+0x3ff/0x400 [] __netif_receive_skb_core+0x12c/0xc40 [] ? kmem_cache_alloc+0x12e/0x270 [] netif_receive_skb_internal+0x3d/0xb0 [] ? get_rx_page_info+0x8e/0xa0 [be2net] [] be_poll+0x6ef/0xd00 [be2net] [] ? irq_exit+0x4f/0x100 [] net_rx_action+0x149/0x3b0 ... This patch is to fix it by linearizing the head skb if it has frag_list set in tipc_buf_append(). Note that we choose to do this before calling skb_unshare(), as __skb_linearize() will avoid skb_copy(). Also, we can not just drop the frag_list either as the early time.

In the Linux kernel, the following vulnerability has been resolved: spi: fix use-after-free of the add_lock mutex Commit 6098475d4cb4 ("spi: Fix deadlock when adding SPI controllers on SPI buses") introduced a per-controller mutex. But mutex_unlock() of said lock is called after the controller is already freed: spi_unregister_controller(ctlr) -> put_device(&ctlr->dev) -> spi_controller_release(dev) -> mutex_unlock(&ctrl->add_lock) Move the put_device() after the mutex_unlock().

In the Linux kernel, the following vulnerability has been resolved: usb: mtu3: fix list_head check warning This is caused by uninitialization of list_head. BUG: KASAN: use-after-free in __list_del_entry_valid+0x34/0xe4 Call trace: dump_backtrace+0x0/0x298 show_stack+0x24/0x34 dump_stack+0x130/0x1a8 print_address_description+0x88/0x56c __kasan_report+0x1b8/0x2a0 kasan_report+0x14/0x20 __asan_load8+0x9c/0xa0 __list_del_entry_valid+0x34/0xe4 mtu3_req_complete+0x4c/0x300 [mtu3] mtu3_gadget_stop+0x168/0x448 [mtu3] usb_gadget_unregister_driver+0x204/0x3a0 unregister_gadget_item+0x44/0xa4

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid racing on fsync_entry_slab by multi filesystem instances As syzbot reported, there is an use-after-free issue during f2fs recovery: Use-after-free write at 0xffff88823bc16040 (in kfence-#10): kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486 f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869 f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945 mount_bdev+0x26c/0x3a0 fs/super.c:1367 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x86/0x270 fs/super.c:1497 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x196f/0x2be0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433 do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae The root cause is multi f2fs filesystem instances can race on accessing global fsync_entry_slab pointer, result in use-after-free issue of slab cache, fixes to init/destroy this slab cache only once during module init/destroy procedure to avoid this issue.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Clear ffs_eventfd in ffs_data_clear. ffs_data_clear is indirectly called from both ffs_fs_kill_sb and ffs_ep0_release, so it ends up being called twice when userland closes ep0 and then unmounts f_fs. If userland provided an eventfd along with function's USB descriptors, it ends up calling eventfd_ctx_put as many times, causing a refcount underflow. NULL-ify ffs_eventfd to prevent these extraneous eventfd_ctx_put calls. Also, set epfiles to NULL right after de-allocating it, for readability. For completeness, ffs_data_clear actually ends up being called thrice, the last call being before the whole ffs structure gets freed, so when this specific sequence happens there is a second underflow happening (but not being reported): /sys/kernel/debug/tracing# modprobe usb_f_fs /sys/kernel/debug/tracing# echo ffs_data_clear > set_ftrace_filter /sys/kernel/debug/tracing# echo function > current_tracer /sys/kernel/debug/tracing# echo 1 > tracing_on (setup gadget, run and kill function userland process, teardown gadget) /sys/kernel/debug/tracing# echo 0 > tracing_on /sys/kernel/debug/tracing# cat trace smartcard-openp-436 [000] ..... 1946.208786: ffs_data_clear <-ffs_data_closed smartcard-openp-431 [000] ..... 1946.279147: ffs_data_clear <-ffs_data_closed smartcard-openp-431 [000] .n... 1946.905512: ffs_data_clear <-ffs_data_put Warning output corresponding to above trace: [ 1946.284139] WARNING: CPU: 0 PID: 431 at lib/refcount.c:28 refcount_warn_saturate+0x110/0x15c [ 1946.293094] refcount_t: underflow; use-after-free. [ 1946.298164] Modules linked in: usb_f_ncm(E) u_ether(E) usb_f_fs(E) hci_uart(E) btqca(E) btrtl(E) btbcm(E) btintel(E) bluetooth(E) nls_ascii(E) nls_cp437(E) vfat(E) fat(E) bcm2835_v4l2(CE) bcm2835_mmal_vchiq(CE) videobuf2_vmalloc(E) videobuf2_memops(E) sha512_generic(E) videobuf2_v4l2(E) sha512_arm(E) videobuf2_common(E) videodev(E) cpufreq_dt(E) snd_bcm2835(CE) brcmfmac(E) mc(E) vc4(E) ctr(E) brcmutil(E) snd_soc_core(E) snd_pcm_dmaengine(E) drbg(E) snd_pcm(E) snd_timer(E) snd(E) soundcore(E) drm_kms_helper(E) cec(E) ansi_cprng(E) rc_core(E) syscopyarea(E) raspberrypi_cpufreq(E) sysfillrect(E) sysimgblt(E) cfg80211(E) max17040_battery(OE) raspberrypi_hwmon(E) fb_sys_fops(E) regmap_i2c(E) ecdh_generic(E) rfkill(E) ecc(E) bcm2835_rng(E) rng_core(E) vchiq(CE) leds_gpio(E) libcomposite(E) fuse(E) configfs(E) ip_tables(E) x_tables(E) autofs4(E) ext4(E) crc16(E) mbcache(E) jbd2(E) crc32c_generic(E) sdhci_iproc(E) sdhci_pltfm(E) sdhci(E) [ 1946.399633] CPU: 0 PID: 431 Comm: smartcard-openp Tainted: G C OE 5.15.0-1-rpi #1 Debian 5.15.3-1 [ 1946.417950] Hardware name: BCM2835 [ 1946.425442] Backtrace: [ 1946.432048] [<c08d60a0>] (dump_backtrace) from [<c08d62ec>] (show_stack+0x20/0x24) [ 1946.448226] r7:00000009 r6:0000001c r5:c04a948c r4:c0a64e2c [ 1946.458412] [<c08d62cc>] (show_stack) from [<c08d9ae0>] (dump_stack+0x28/0x30) [ 1946.470380] [<c08d9ab8>] (dump_stack) from [<c0123500>] (__warn+0xe8/0x154) [ 1946.482067] r5:c04a948c r4:c0a71dc8 [ 1946.490184] [<c0123418>] (__warn) from [<c08d6948>] (warn_slowpath_fmt+0xa0/0xe4) [ 1946.506758] r7:00000009 r6:0000001c r5:c0a71dc8 r4:c0a71e04 [ 1946.517070] [<c08d68ac>] (warn_slowpath_fmt) from [<c04a948c>] (refcount_warn_saturate+0x110/0x15c) [ 1946.535309] r8:c0100224 r7:c0dfcb84 r6:ffffffff r5:c3b84c00 r4:c24a17c0 [ 1946.546708] [<c04a937c>] (refcount_warn_saturate) from [<c0380134>] (eventfd_ctx_put+0x48/0x74) [ 1946.564476] [<c03800ec>] (eventfd_ctx_put) from [<bf5464e8>] (ffs_data_clear+0xd0/0x118 [usb_f_fs]) [ 1946.582664] r5:c3b84c00 r4:c2695b00 [ 1946.590668] [<bf546418>] (ffs_data_clear [usb_f_fs]) from [<bf547cc0>] (ffs_data_closed+0x9c/0x150 [usb_f_fs]) [ 1946.609608] r5:bf54d014 r4:c2695b00 [ 1946.617522] [<bf547c24>] (ffs_data_closed [usb_f_fs]) from [<bf547da0>] (ffs_fs_kill_sb+0x2c/0x30 [usb_f_fs]) [ 1946.636217] r7:c0dfcb ---truncated---

A use-after-free flaw was found in the add_partition in block/partitions/core.c in the Linux kernel. A local attacker with user privileges could cause a denial of service on the system. The issue results from the lack of code cleanup when device_add call fails when adding a partition to the disk.

In the Linux kernel, the following vulnerability has been resolved: xen: privcmd: Fix possible access to a freed kirqfd instance Nothing prevents simultaneous ioctl calls to privcmd_irqfd_assign() and privcmd_irqfd_deassign(). If that happens, it is possible that a kirqfd created and added to the irqfds_list by privcmd_irqfd_assign() may get removed by another thread executing privcmd_irqfd_deassign(), while the former is still using it after dropping the locks. This can lead to a situation where an already freed kirqfd instance may be accessed and cause kernel oops. Use SRCU locking to prevent the same, as is done for the KVM implementation for irqfds.

In the Linux kernel, the following vulnerability has been resolved: spi: lpspi: Avoid potential use-after-free in probe() fsl_lpspi_probe() is allocating/disposing memory manually with spi_alloc_host()/spi_alloc_target(), but uses devm_spi_register_controller(). In case of error after the latter call the memory will be explicitly freed in the probe function by spi_controller_put() call, but used afterwards by "devm" management outside probe() (spi_unregister_controller() <- devm_spi_unregister() below). Unable to handle kernel NULL pointer dereference at virtual address 0000000000000070 ... Call trace: kernfs_find_ns kernfs_find_and_get_ns sysfs_remove_group sysfs_remove_groups device_remove_attrs device_del spi_unregister_controller devm_spi_unregister release_nodes devres_release_all really_probe driver_probe_device __device_attach_driver bus_for_each_drv __device_attach device_initial_probe bus_probe_device deferred_probe_work_func process_one_work worker_thread kthread ret_from_fork

In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix possible use-after-free and null-ptr-deref The pernet operations structure for the subsystem must be registered before registering the generic netlink family.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: Avoid potential use-after-free in hci_error_reset While handling the HCI_EV_HARDWARE_ERROR event, if the underlying BT controller is not responding, the GPIO reset mechanism would free the hci_dev and lead to a use-after-free in hci_error_reset. Here's the call trace observed on a ChromeOS device with Intel AX201: queue_work_on+0x3e/0x6c __hci_cmd_sync_sk+0x2ee/0x4c0 [bluetooth <HASH:3b4a6>] ? init_wait_entry+0x31/0x31 __hci_cmd_sync+0x16/0x20 [bluetooth <HASH:3b4a 6>] hci_error_reset+0x4f/0xa4 [bluetooth <HASH:3b4a 6>] process_one_work+0x1d8/0x33f worker_thread+0x21b/0x373 kthread+0x13a/0x152 ? pr_cont_work+0x54/0x54 ? kthread_blkcg+0x31/0x31 ret_from_fork+0x1f/0x30 This patch holds the reference count on the hci_dev while processing a HCI_EV_HARDWARE_ERROR event to avoid potential crash.

In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Fix KASAN issue with tasklet KASAN testing revealed the following issue assocated with freeing an IRQ. [50006.466686] Call Trace: [50006.466691] <IRQ> [50006.489538] dump_stack+0x5c/0x80 [50006.493475] print_address_description.constprop.6+0x1a/0x150 [50006.499872] ? irdma_sc_process_ceq+0x483/0x790 [irdma] [50006.505742] ? irdma_sc_process_ceq+0x483/0x790 [irdma] [50006.511644] kasan_report.cold.11+0x7f/0x118 [50006.516572] ? irdma_sc_process_ceq+0x483/0x790 [irdma] [50006.522473] irdma_sc_process_ceq+0x483/0x790 [irdma] [50006.528232] irdma_process_ceq+0xb2/0x400 [irdma] [50006.533601] ? irdma_hw_flush_wqes_callback+0x370/0x370 [irdma] [50006.540298] irdma_ceq_dpc+0x44/0x100 [irdma] [50006.545306] tasklet_action_common.isra.14+0x148/0x2c0 [50006.551096] __do_softirq+0x1d0/0xaf8 [50006.555396] irq_exit_rcu+0x219/0x260 [50006.559670] irq_exit+0xa/0x20 [50006.563320] smp_apic_timer_interrupt+0x1bf/0x690 [50006.568645] apic_timer_interrupt+0xf/0x20 [50006.573341] </IRQ> The issue is that a tasklet could be pending on another core racing the delete of the irq. Fix by insuring any scheduled tasklet is killed after deleting the irq.

In the Linux kernel, the following vulnerability has been resolved: soc: qcom: pmic_glink_altmode: fix drm bridge use-after-free A recent DRM series purporting to simplify support for "transparent bridges" and handling of probe deferrals ironically exposed a use-after-free issue on pmic_glink_altmode probe deferral. This has manifested itself as the display subsystem occasionally failing to initialise and NULL-pointer dereferences during boot of machines like the Lenovo ThinkPad X13s. Specifically, the dp-hpd bridge is currently registered before all resources have been acquired which means that it can also be deregistered on probe deferrals. In the meantime there is a race window where the new aux bridge driver (or PHY driver previously) may have looked up the dp-hpd bridge and stored a (non-reference-counted) pointer to the bridge which is about to be deallocated. When the display controller is later initialised, this triggers a use-after-free when attaching the bridges: dp -> aux -> dp-hpd (freed) which may, for example, result in the freed bridge failing to attach: [drm:drm_bridge_attach [drm]] *ERROR* failed to attach bridge /soc@0/phy@88eb000 to encoder TMDS-31: -16 or a NULL-pointer dereference: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 ... Call trace: drm_bridge_attach+0x70/0x1a8 [drm] drm_aux_bridge_attach+0x24/0x38 [aux_bridge] drm_bridge_attach+0x80/0x1a8 [drm] dp_bridge_init+0xa8/0x15c [msm] msm_dp_modeset_init+0x28/0xc4 [msm] The DRM bridge implementation is clearly fragile and implicitly built on the assumption that bridges may never go away. In this case, the fix is to move the bridge registration in the pmic_glink_altmode driver to after all resources have been looked up. Incidentally, with the new dp-hpd bridge implementation, which registers child devices, this is also a requirement due to a long-standing issue in driver core that can otherwise lead to a probe deferral loop (see commit fbc35b45f9f6 ("Add documentation on meaning of -EPROBE_DEFER")). [DB: slightly fixed commit message by adding the word 'commit']

In the Linux kernel through 6.7.1, there is a use-after-free in cec_queue_msg_fh, related to drivers/media/cec/core/cec-adap.c and drivers/media/cec/core/cec-api.c.

In the Linux kernel, the following vulnerability has been resolved: net: atlantic: Fix DMA mapping for PTP hwts ring Function aq_ring_hwts_rx_alloc() maps extra AQ_CFG_RXDS_DEF bytes for PTP HWTS ring but then generic aq_ring_free() does not take this into account. Create and use a specific function to free HWTS ring to fix this issue. Trace: [ 215.351607] ------------[ cut here ]------------ [ 215.351612] DMA-API: atlantic 0000:4b:00.0: device driver frees DMA memory with different size [device address=0x00000000fbdd0000] [map size=34816 bytes] [unmap size=32768 bytes] [ 215.351635] WARNING: CPU: 33 PID: 10759 at kernel/dma/debug.c:988 check_unmap+0xa6f/0x2360 ... [ 215.581176] Call Trace: [ 215.583632] <TASK> [ 215.585745] ? show_trace_log_lvl+0x1c4/0x2df [ 215.590114] ? show_trace_log_lvl+0x1c4/0x2df [ 215.594497] ? debug_dma_free_coherent+0x196/0x210 [ 215.599305] ? check_unmap+0xa6f/0x2360 [ 215.603147] ? __warn+0xca/0x1d0 [ 215.606391] ? check_unmap+0xa6f/0x2360 [ 215.610237] ? report_bug+0x1ef/0x370 [ 215.613921] ? handle_bug+0x3c/0x70 [ 215.617423] ? exc_invalid_op+0x14/0x50 [ 215.621269] ? asm_exc_invalid_op+0x16/0x20 [ 215.625480] ? check_unmap+0xa6f/0x2360 [ 215.629331] ? mark_lock.part.0+0xca/0xa40 [ 215.633445] debug_dma_free_coherent+0x196/0x210 [ 215.638079] ? __pfx_debug_dma_free_coherent+0x10/0x10 [ 215.643242] ? slab_free_freelist_hook+0x11d/0x1d0 [ 215.648060] dma_free_attrs+0x6d/0x130 [ 215.651834] aq_ring_free+0x193/0x290 [atlantic] [ 215.656487] aq_ptp_ring_free+0x67/0x110 [atlantic] ... [ 216.127540] ---[ end trace 6467e5964dd2640b ]--- [ 216.132160] DMA-API: Mapped at: [ 216.132162] debug_dma_alloc_coherent+0x66/0x2f0 [ 216.132165] dma_alloc_attrs+0xf5/0x1b0 [ 216.132168] aq_ring_hwts_rx_alloc+0x150/0x1f0 [atlantic] [ 216.132193] aq_ptp_ring_alloc+0x1bb/0x540 [atlantic] [ 216.132213] aq_nic_init+0x4a1/0x760 [atlantic]

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix racing between bpf_timer_cancel_and_free and bpf_timer_cancel The following race is possible between bpf_timer_cancel_and_free and bpf_timer_cancel. It will lead a UAF on the timer->timer. bpf_timer_cancel(); spin_lock(); t = timer->time; spin_unlock(); bpf_timer_cancel_and_free(); spin_lock(); t = timer->timer; timer->timer = NULL; spin_unlock(); hrtimer_cancel(&t->timer); kfree(t); /* UAF on t */ hrtimer_cancel(&t->timer); In bpf_timer_cancel_and_free, this patch frees the timer->timer after a rcu grace period. This requires a rcu_head addition to the "struct bpf_hrtimer". Another kfree(t) happens in bpf_timer_init, this does not need a kfree_rcu because it is still under the spin_lock and timer->timer has not been visible by others yet. In bpf_timer_cancel, rcu_read_lock() is added because this helper can be used in a non rcu critical section context (e.g. from a sleepable bpf prog). Other timer->timer usages in helpers.c have been audited, bpf_timer_cancel() is the only place where timer->timer is used outside of the spin_lock. Another solution considered is to mark a t->flag in bpf_timer_cancel and clear it after hrtimer_cancel() is done. In bpf_timer_cancel_and_free, it busy waits for the flag to be cleared before kfree(t). This patch goes with a straight forward solution and frees timer->timer after a rcu grace period.

In the Linux kernel, the following vulnerability has been resolved: btrfs: wait for fixup workers before stopping cleaner kthread during umount During unmount, at close_ctree(), we have the following steps in this order: 1) Park the cleaner kthread - this doesn't destroy the kthread, it basically halts its execution (wake ups against it work but do nothing); 2) We stop the cleaner kthread - this results in freeing the respective struct task_struct; 3) We call btrfs_stop_all_workers() which waits for any jobs running in all the work queues and then free the work queues. Syzbot reported a case where a fixup worker resulted in a crash when doing a delayed iput on its inode while attempting to wake up the cleaner at btrfs_add_delayed_iput(), because the task_struct of the cleaner kthread was already freed. This can happen during unmount because we don't wait for any fixup workers still running before we call kthread_stop() against the cleaner kthread, which stops and free all its resources. Fix this by waiting for any fixup workers at close_ctree() before we call kthread_stop() against the cleaner and run pending delayed iputs. The stack traces reported by syzbot were the following: BUG: KASAN: slab-use-after-free in __lock_acquire+0x77/0x2050 kernel/locking/lockdep.c:5065 Read of size 8 at addr ffff8880272a8a18 by task kworker/u8:3/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.12.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: btrfs-fixup 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:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __lock_acquire+0x77/0x2050 kernel/locking/lockdep.c:5065 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __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+0xb0/0x1480 kernel/sched/core.c:4154 btrfs_writepage_fixup_worker+0xc16/0xdf0 fs/btrfs/inode.c:2842 btrfs_work_helper+0x390/0xc50 fs/btrfs/async-thread.c:314 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 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:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4187 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1107 copy_process+0x5d1/0x3d50 kernel/fork.c:2206 kernel_clone+0x223/0x880 kernel/fork.c:2787 kernel_thread+0x1bc/0x240 kernel/fork.c:2849 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:765 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 61: 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:579 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:230 [inline] slab_free_h ---truncated---

In the Linux kernel, the following vulnerability has been resolved: iommu/s390: Implement blocking domain This fixes a crash when surprise hot-unplugging a PCI device. This crash happens because during hot-unplug __iommu_group_set_domain_nofail() attaching the default domain fails when the platform no longer recognizes the device as it has already been removed and we end up with a NULL domain pointer and UAF. This is exactly the case referred to in the second comment in __iommu_device_set_domain() and just as stated there if we can instead attach the blocking domain the UAF is prevented as this can handle the already removed device. Implement the blocking domain to use this handling. With this change, the crash is fixed but we still hit a warning attempting to change DMA ownership on a blocked device.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix NULL ptr deref in crypto_aead_setkey() Neither SMB3.0 or SMB3.02 supports encryption negotiate context, so when SMB2_GLOBAL_CAP_ENCRYPTION flag is set in the negotiate response, the client uses AES-128-CCM as the default cipher. See MS-SMB2 3.3.5.4. Commit b0abcd65ec54 ("smb: client: fix UAF in async decryption") added a @server->cipher_type check to conditionally call smb3_crypto_aead_allocate(), but that check would always be false as @server->cipher_type is unset for SMB3.02. Fix the following KASAN splat by setting @server->cipher_type for SMB3.02 as well. mount.cifs //srv/share /mnt -o vers=3.02,seal,... BUG: KASAN: null-ptr-deref in crypto_aead_setkey+0x2c/0x130 Read of size 8 at addr 0000000000000020 by task mount.cifs/1095 CPU: 1 UID: 0 PID: 1095 Comm: mount.cifs Not tainted 6.12.0 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x80 ? crypto_aead_setkey+0x2c/0x130 kasan_report+0xda/0x110 ? crypto_aead_setkey+0x2c/0x130 crypto_aead_setkey+0x2c/0x130 crypt_message+0x258/0xec0 [cifs] ? __asan_memset+0x23/0x50 ? __pfx_crypt_message+0x10/0x10 [cifs] ? mark_lock+0xb0/0x6a0 ? hlock_class+0x32/0xb0 ? mark_lock+0xb0/0x6a0 smb3_init_transform_rq+0x352/0x3f0 [cifs] ? lock_acquire.part.0+0xf4/0x2a0 smb_send_rqst+0x144/0x230 [cifs] ? __pfx_smb_send_rqst+0x10/0x10 [cifs] ? hlock_class+0x32/0xb0 ? smb2_setup_request+0x225/0x3a0 [cifs] ? __pfx_cifs_compound_last_callback+0x10/0x10 [cifs] compound_send_recv+0x59b/0x1140 [cifs] ? __pfx_compound_send_recv+0x10/0x10 [cifs] ? __create_object+0x5e/0x90 ? hlock_class+0x32/0xb0 ? do_raw_spin_unlock+0x9a/0xf0 cifs_send_recv+0x23/0x30 [cifs] SMB2_tcon+0x3ec/0xb30 [cifs] ? __pfx_SMB2_tcon+0x10/0x10 [cifs] ? lock_acquire.part.0+0xf4/0x2a0 ? __pfx_lock_release+0x10/0x10 ? do_raw_spin_trylock+0xc6/0x120 ? lock_acquire+0x3f/0x90 ? _get_xid+0x16/0xd0 [cifs] ? __pfx_SMB2_tcon+0x10/0x10 [cifs] ? cifs_get_smb_ses+0xcdd/0x10a0 [cifs] cifs_get_smb_ses+0xcdd/0x10a0 [cifs] ? __pfx_cifs_get_smb_ses+0x10/0x10 [cifs] ? cifs_get_tcp_session+0xaa0/0xca0 [cifs] cifs_mount_get_session+0x8a/0x210 [cifs] dfs_mount_share+0x1b0/0x11d0 [cifs] ? __pfx___lock_acquire+0x10/0x10 ? __pfx_dfs_mount_share+0x10/0x10 [cifs] ? lock_acquire.part.0+0xf4/0x2a0 ? find_held_lock+0x8a/0xa0 ? hlock_class+0x32/0xb0 ? lock_release+0x203/0x5d0 cifs_mount+0xb3/0x3d0 [cifs] ? do_raw_spin_trylock+0xc6/0x120 ? __pfx_cifs_mount+0x10/0x10 [cifs] ? lock_acquire+0x3f/0x90 ? find_nls+0x16/0xa0 ? smb3_update_mnt_flags+0x372/0x3b0 [cifs] cifs_smb3_do_mount+0x1e2/0xc80 [cifs] ? __pfx_vfs_parse_fs_string+0x10/0x10 ? __pfx_cifs_smb3_do_mount+0x10/0x10 [cifs] smb3_get_tree+0x1bf/0x330 [cifs] vfs_get_tree+0x4a/0x160 path_mount+0x3c1/0xfb0 ? kasan_quarantine_put+0xc7/0x1d0 ? __pfx_path_mount+0x10/0x10 ? kmem_cache_free+0x118/0x3e0 ? user_path_at+0x74/0xa0 __x64_sys_mount+0x1a6/0x1e0 ? __pfx___x64_sys_mount+0x10/0x10 ? mark_held_locks+0x1a/0x90 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: thermal: core: Free tzp copy along with the thermal zone The object pointed to by tz->tzp may still be accessed after being freed in thermal_zone_device_unregister(), so move the freeing of it to the point after the removal completion has been completed at which it cannot be accessed any more.

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Don't free job in TDR Freeing job in TDR is not safe as TDR can pass the run_job thread resulting in UAF. It is only safe for free job to naturally be called by the scheduler. Rather free job in TDR, add to pending list. (cherry picked from commit ea2f6a77d0c40d97f4a4dc93fee4afe15d94926d)

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: fix UaF read in mptcp_pm_nl_rm_addr_or_subflow Syzkaller reported this splat: ================================================================== BUG: KASAN: slab-use-after-free in mptcp_pm_nl_rm_addr_or_subflow+0xb44/0xcc0 net/mptcp/pm_netlink.c:881 Read of size 4 at addr ffff8880569ac858 by task syz.1.2799/14662 CPU: 0 UID: 0 PID: 14662 Comm: syz.1.2799 Not tainted 6.12.0-rc2-syzkaller-00307-g36c254515dc6 #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+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 mptcp_pm_nl_rm_addr_or_subflow+0xb44/0xcc0 net/mptcp/pm_netlink.c:881 mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:914 [inline] mptcp_nl_remove_id_zero_address+0x305/0x4a0 net/mptcp/pm_netlink.c:1572 mptcp_pm_nl_del_addr_doit+0x5c9/0x770 net/mptcp/pm_netlink.c:1603 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg net/socket.c:744 [inline] ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2607 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661 __sys_sendmsg+0x117/0x1f0 net/socket.c:2690 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fe4579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f574556c EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000020000140 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 5387: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] subflow_create_ctx+0x87/0x2a0 net/mptcp/subflow.c:1803 subflow_ulp_init+0xc3/0x4d0 net/mptcp/subflow.c:1956 __tcp_set_ulp net/ipv4/tcp_ulp.c:146 [inline] tcp_set_ulp+0x326/0x7f0 net/ipv4/tcp_ulp.c:167 mptcp_subflow_create_socket+0x4ae/0x10a0 net/mptcp/subflow.c:1764 __mptcp_subflow_connect+0x3cc/0x1490 net/mptcp/subflow.c:1592 mptcp_pm_create_subflow_or_signal_addr+0xbda/0x23a0 net/mptcp/pm_netlink.c:642 mptcp_pm_nl_fully_established net/mptcp/pm_netlink.c:650 [inline] mptcp_pm_nl_work+0x3a1/0x4f0 net/mptcp/pm_netlink.c:943 mptcp_worker+0x15a/0x1240 net/mptcp/protocol.c:2777 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/ke ---truncated---

In the Linux kernel, the following vulnerability has been resolved: fbdev: efifb: Register sysfs groups through driver core The driver core can register and cleanup sysfs groups already. Make use of that functionality to simplify the error handling and cleanup. Also avoid a UAF race during unregistering where the sysctl attributes were usable after the info struct was freed.

In the Linux kernel, the following vulnerability has been resolved: net/ncsi: Disable the ncsi work before freeing the associated structure The work function can run after the ncsi device is freed, resulting in use-after-free bugs or kernel panic.

In the Linux kernel, the following vulnerability has been resolved: crypto: iaa - Fix potential use after free bug The free_device_compression_mode(iaa_device, device_mode) function frees "device_mode" but it iss passed to iaa_compression_modes[i]->free() a few lines later resulting in a use after free. The good news is that, so far as I can tell, nothing implements the ->free() function and the use after free happens in dead code. But, with this fix, when something does implement it, we'll be ready. :)

In the Linux kernel, the following vulnerability has been resolved: scsi: pm80xx: Set phy->enable_completion only when we wait for it pm8001_phy_control() populates the enable_completion pointer with a stack address, sends a PHY_LINK_RESET / PHY_HARD_RESET, waits 300 ms, and returns. The problem arises when a phy control response comes late. After 300 ms the pm8001_phy_control() function returns and the passed enable_completion stack address is no longer valid. Late phy control response invokes complete() on a dangling enable_completion pointer which leads to a kernel crash.

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Handle mailbox timeouts in lpfc_get_sfp_info The MBX_TIMEOUT return code is not handled in lpfc_get_sfp_info and the routine unconditionally frees submitted mailbox commands regardless of return status. The issue is that for MBX_TIMEOUT cases, when firmware returns SFP information at a later time, that same mailbox memory region references previously freed memory in its cmpl routine. Fix by adding checks for the MBX_TIMEOUT return code. During mailbox resource cleanup, check the mbox flag to make sure that the wait did not timeout. If the MBOX_WAKE flag is not set, then do not free the resources because it will be freed when firmware completes the mailbox at a later time in its cmpl routine. Also, increase the timeout from 30 to 60 seconds to accommodate boot scripts requiring longer timeouts.

In the Linux kernel, the following vulnerability has been resolved: nvme: move stopping keep-alive into nvme_uninit_ctrl() Commit 4733b65d82bd ("nvme: start keep-alive after admin queue setup") moves starting keep-alive from nvme_start_ctrl() into nvme_init_ctrl_finish(), but don't move stopping keep-alive into nvme_uninit_ctrl(), so keep-alive work can be started and keep pending after failing to start controller, finally use-after-free is triggered if nvme host driver is unloaded. This patch fixes kernel panic when running nvme/004 in case that connection failure is triggered, by moving stopping keep-alive into nvme_uninit_ctrl(). This way is reasonable because keep-alive is now started in nvme_init_ctrl_finish().

In the Linux kernel, the following vulnerability has been resolved: netem: fix return value if duplicate enqueue fails There is a bug in netem_enqueue() introduced by commit 5845f706388a ("net: netem: fix skb length BUG_ON in __skb_to_sgvec") that can lead to a use-after-free. This commit made netem_enqueue() always return NET_XMIT_SUCCESS when a packet is duplicated, which can cause the parent qdisc's q.qlen to be mistakenly incremented. When this happens qlen_notify() may be skipped on the parent during destruction, leaving a dangling pointer for some classful qdiscs like DRR. There are two ways for the bug happen: - If the duplicated packet is dropped by rootq->enqueue() and then the original packet is also dropped. - If rootq->enqueue() sends the duplicated packet to a different qdisc and the original packet is dropped. In both cases NET_XMIT_SUCCESS is returned even though no packets are enqueued at the netem qdisc. The fix is to defer the enqueue of the duplicate packet until after the original packet has been guaranteed to return NET_XMIT_SUCCESS.

In the Linux kernel, the following vulnerability has been resolved: kcm: Serialise kcm_sendmsg() for the same socket. syzkaller reported UAF in kcm_release(). [0] The scenario is 1. Thread A builds a skb with MSG_MORE and sets kcm->seq_skb. 2. Thread A resumes building skb from kcm->seq_skb but is blocked by sk_stream_wait_memory() 3. Thread B calls sendmsg() concurrently, finishes building kcm->seq_skb and puts the skb to the write queue 4. Thread A faces an error and finally frees skb that is already in the write queue 5. kcm_release() does double-free the skb in the write queue When a thread is building a MSG_MORE skb, another thread must not touch it. Let's add a per-sk mutex and serialise kcm_sendmsg(). [0]: BUG: KASAN: slab-use-after-free in __skb_unlink include/linux/skbuff.h:2366 [inline] BUG: KASAN: slab-use-after-free in __skb_dequeue include/linux/skbuff.h:2385 [inline] BUG: KASAN: slab-use-after-free in __skb_queue_purge_reason include/linux/skbuff.h:3175 [inline] BUG: KASAN: slab-use-after-free in __skb_queue_purge include/linux/skbuff.h:3181 [inline] BUG: KASAN: slab-use-after-free in kcm_release+0x170/0x4c8 net/kcm/kcmsock.c:1691 Read of size 8 at addr ffff0000ced0fc80 by task syz-executor329/6167 CPU: 1 PID: 6167 Comm: syz-executor329 Tainted: G B 6.8.0-rc5-syzkaller-g9abbc24128bc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x178/0x518 mm/kasan/report.c:488 kasan_report+0xd8/0x138 mm/kasan/report.c:601 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 __skb_unlink include/linux/skbuff.h:2366 [inline] __skb_dequeue include/linux/skbuff.h:2385 [inline] __skb_queue_purge_reason include/linux/skbuff.h:3175 [inline] __skb_queue_purge include/linux/skbuff.h:3181 [inline] kcm_release+0x170/0x4c8 net/kcm/kcmsock.c:1691 __sock_release net/socket.c:659 [inline] sock_close+0xa4/0x1e8 net/socket.c:1421 __fput+0x30c/0x738 fs/file_table.c:376 ____fput+0x20/0x30 fs/file_table.c:404 task_work_run+0x230/0x2e0 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x618/0x1f64 kernel/exit.c:871 do_group_exit+0x194/0x22c kernel/exit.c:1020 get_signal+0x1500/0x15ec kernel/signal.c:2893 do_signal+0x23c/0x3b44 arch/arm64/kernel/signal.c:1249 do_notify_resume+0x74/0x1f4 arch/arm64/kernel/entry-common.c:148 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_svc+0xac/0x168 arch/arm64/kernel/entry-common.c:713 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 Allocated by task 6166: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_alloc_info+0x70/0x84 mm/kasan/generic.c:626 unpoison_slab_object mm/kasan/common.c:314 [inline] __kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_node+0x204/0x4c0 mm/slub.c:3903 __alloc_skb+0x19c/0x3d8 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1296 [inline] kcm_sendmsg+0x1d3c/0x2124 net/kcm/kcmsock.c:783 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_sendmsg+0x220/0x2c0 net/socket.c:768 splice_to_socket+0x7cc/0xd58 fs/splice.c:889 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0xec/0x1d8 fs/splice.c:1164 splice_direct_to_actor+0x438/0xa0c fs/splice.c:1108 do_splice_direct_actor ---truncated---

In the Linux kernel, the following vulnerability has been resolved: cgroup/cpuset: Prevent UAF in proc_cpuset_show() An UAF can happen when /proc/cpuset is read as reported in [1]. This can be reproduced by the following methods: 1.add an mdelay(1000) before acquiring the cgroup_lock In the cgroup_path_ns function. 2.$cat /proc/<pid>/cpuset repeatly. 3.$mount -t cgroup -o cpuset cpuset /sys/fs/cgroup/cpuset/ $umount /sys/fs/cgroup/cpuset/ repeatly. The race that cause this bug can be shown as below: (umount) | (cat /proc/<pid>/cpuset) css_release | proc_cpuset_show css_release_work_fn | css = task_get_css(tsk, cpuset_cgrp_id); css_free_rwork_fn | cgroup_path_ns(css->cgroup, ...); cgroup_destroy_root | mutex_lock(&cgroup_mutex); rebind_subsystems | cgroup_free_root | | // cgrp was freed, UAF | cgroup_path_ns_locked(cgrp,..); When the cpuset is initialized, the root node top_cpuset.css.cgrp will point to &cgrp_dfl_root.cgrp. In cgroup v1, the mount operation will allocate cgroup_root, and top_cpuset.css.cgrp will point to the allocated &cgroup_root.cgrp. When the umount operation is executed, top_cpuset.css.cgrp will be rebound to &cgrp_dfl_root.cgrp. The problem is that when rebinding to cgrp_dfl_root, there are cases where the cgroup_root allocated by setting up the root for cgroup v1 is cached. This could lead to a Use-After-Free (UAF) if it is subsequently freed. The descendant cgroups of cgroup v1 can only be freed after the css is released. However, the css of the root will never be released, yet the cgroup_root should be freed when it is unmounted. This means that obtaining a reference to the css of the root does not guarantee that css.cgrp->root will not be freed. Fix this problem by using rcu_read_lock in proc_cpuset_show(). As cgroup_root is kfree_rcu after commit d23b5c577715 ("cgroup: Make operations on the cgroup root_list RCU safe"), css->cgroup won't be freed during the critical section. To call cgroup_path_ns_locked, css_set_lock is needed, so it is safe to replace task_get_css with task_css. [1] https://syzkaller.appspot.com/bug?extid=9b1ff7be974a403aa4cd

In the Linux kernel, the following vulnerability has been resolved: libceph: fix race between delayed_work() and ceph_monc_stop() The way the delayed work is handled in ceph_monc_stop() is prone to races with mon_fault() and possibly also finish_hunting(). Both of these can requeue the delayed work which wouldn't be canceled by any of the following code in case that happens after cancel_delayed_work_sync() runs -- __close_session() doesn't mess with the delayed work in order to avoid interfering with the hunting interval logic. This part was missed in commit b5d91704f53e ("libceph: behave in mon_fault() if cur_mon < 0") and use-after-free can still ensue on monc and objects that hang off of it, with monc->auth and monc->monmap being particularly susceptible to quickly being reused. To fix this: - clear monc->cur_mon and monc->hunting as part of closing the session in ceph_monc_stop() - bail from delayed_work() if monc->cur_mon is cleared, similar to how it's done in mon_fault() and finish_hunting() (based on monc->hunting) - call cancel_delayed_work_sync() after the session is closed

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unregister flowtable hooks on netns exit Unregister flowtable hooks before they are releases via nf_tables_flowtable_destroy() otherwise hook core reports UAF. BUG: KASAN: use-after-free in nf_hook_entries_grow+0x5a7/0x700 net/netfilter/core.c:142 net/netfilter/core.c:142 Read of size 4 at addr ffff8880736f7438 by task syz-executor579/3666 CPU: 0 PID: 3666 Comm: syz-executor579 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] __dump_stack lib/dump_stack.c:88 [inline] lib/dump_stack.c:106 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 lib/dump_stack.c:106 print_address_description+0x65/0x380 mm/kasan/report.c:247 mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] __kasan_report mm/kasan/report.c:433 [inline] mm/kasan/report.c:450 kasan_report+0x19a/0x1f0 mm/kasan/report.c:450 mm/kasan/report.c:450 nf_hook_entries_grow+0x5a7/0x700 net/netfilter/core.c:142 net/netfilter/core.c:142 __nf_register_net_hook+0x27e/0x8d0 net/netfilter/core.c:429 net/netfilter/core.c:429 nf_register_net_hook+0xaa/0x180 net/netfilter/core.c:571 net/netfilter/core.c:571 nft_register_flowtable_net_hooks+0x3c5/0x730 net/netfilter/nf_tables_api.c:7232 net/netfilter/nf_tables_api.c:7232 nf_tables_newflowtable+0x2022/0x2cf0 net/netfilter/nf_tables_api.c:7430 net/netfilter/nf_tables_api.c:7430 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:513 [inline] nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline] nfnetlink_rcv_batch net/netfilter/nfnetlink.c:513 [inline] net/netfilter/nfnetlink.c:652 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline] net/netfilter/nfnetlink.c:652 nfnetlink_rcv+0x10e6/0x2550 net/netfilter/nfnetlink.c:652 net/netfilter/nfnetlink.c:652 __nft_release_hook() calls nft_unregister_flowtable_net_hooks() which only unregisters the hooks, then after RCU grace period, it is guaranteed that no packets add new entries to the flowtable (no flow offload rules and flowtable hooks are reachable from packet path), so it is safe to call nf_flow_table_free() which cleans up the remaining entries from the flowtable (both software and hardware) and it unbinds the flow_block.

mm/rmap.c in the Linux kernel before 5.19.7 has a use-after-free related to leaf anon_vma double reuse.

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix error pbuf checking Syz reports a problem, which boils down to NULL vs IS_ERR inconsistent error handling in io_alloc_pbuf_ring(). KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:__io_remove_buffers+0xac/0x700 io_uring/kbuf.c:341 Call Trace: <TASK> io_put_bl io_uring/kbuf.c:378 [inline] io_destroy_buffers+0x14e/0x490 io_uring/kbuf.c:392 io_ring_ctx_free+0xa00/0x1070 io_uring/io_uring.c:2613 io_ring_exit_work+0x80f/0x8a0 io_uring/io_uring.c:2844 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 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

In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Fix potential memory leak in the timestamp extension If fetching of userspace memory fails during the main loop, all drm sync objs looked up until that point will be leaked because of the missing drm_syncobj_put. Fix it by exporting and using a common cleanup helper. (cherry picked from commit 753ce4fea62182c77e1691ab4f9022008f25b62e)

In the Linux kernel, the following vulnerability has been resolved: net: mediatek: Fix potential NULL pointer dereference in dummy net_device handling Move the freeing of the dummy net_device from mtk_free_dev() to mtk_remove(). Previously, if alloc_netdev_dummy() failed in mtk_probe(), eth->dummy_dev would be NULL. The error path would then call mtk_free_dev(), which in turn called free_netdev() assuming dummy_dev was allocated (but it was not), potentially causing a NULL pointer dereference. By moving free_netdev() to mtk_remove(), we ensure it's only called when mtk_probe() has succeeded and dummy_dev is fully allocated. This addresses a potential NULL pointer dereference detected by Smatch[1].

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: core: remove lock of otg mode during gadget suspend/resume to avoid deadlock When config CONFIG_USB_DWC3_DUAL_ROLE is selected, and trigger system to enter suspend status with below command: echo mem > /sys/power/state There will be a deadlock issue occurring. Detailed invoking path as below: dwc3_suspend_common() spin_lock_irqsave(&dwc->lock, flags); <-- 1st dwc3_gadget_suspend(dwc); dwc3_gadget_soft_disconnect(dwc); spin_lock_irqsave(&dwc->lock, flags); <-- 2nd This issue is exposed by commit c7ebd8149ee5 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend") that removes the code of checking whether dwc->gadget_driver is NULL or not. It causes the following code is executed and deadlock occurs when trying to get the spinlock. In fact, the root cause is the commit 5265397f9442("usb: dwc3: Remove DWC3 locking during gadget suspend/resume") that forgot to remove the lock of otg mode. So, remove the redundant lock of otg mode during gadget suspend/resume.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: Ignore too large handle values in BIG hci_le_big_sync_established_evt is necessary to filter out cases where the handle value is belonging to ida id range, otherwise ida will be erroneously released in hci_conn_cleanup.

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix DIO failure due to insufficient transaction credits The code in ocfs2_dio_end_io_write() estimates number of necessary transaction credits using ocfs2_calc_extend_credits(). This however does not take into account that the IO could be arbitrarily large and can contain arbitrary number of extents. Extent tree manipulations do often extend the current transaction but not in all of the cases. For example if we have only single block extents in the tree, ocfs2_mark_extent_written() will end up calling ocfs2_replace_extent_rec() all the time and we will never extend the current transaction and eventually exhaust all the transaction credits if the IO contains many single block extents. Once that happens a WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to this error. This was actually triggered by one of our customers on a heavily fragmented OCFS2 filesystem. To fix the issue make sure the transaction always has enough credits for one extent insert before each call of ocfs2_mark_extent_written(). Heming Zhao said: ------ PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error" PID: xxx TASK: xxxx CPU: 5 COMMAND: "SubmitThread-CA" #0 machine_kexec at ffffffff8c069932 #1 __crash_kexec at ffffffff8c1338fa #2 panic at ffffffff8c1d69b9 #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2] #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2] #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2] #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2] #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2] #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2] #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2] #10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2] #11 dio_complete at ffffffff8c2b9fa7 #12 do_blockdev_direct_IO at ffffffff8c2bc09f #13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2] #14 generic_file_direct_write at ffffffff8c1dcf14 #15 __generic_file_write_iter at ffffffff8c1dd07b #16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2] #17 aio_write at ffffffff8c2cc72e #18 kmem_cache_alloc at ffffffff8c248dde #19 do_io_submit at ffffffff8c2ccada #20 do_syscall_64 at ffffffff8c004984 #21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Add NULL pointer check for kzalloc [Why & How] Check return pointer of kzalloc before using it.

In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Fix potential memory leak in the performance extension If fetching of userspace memory fails during the main loop, all drm sync objs looked up until that point will be leaked because of the missing drm_syncobj_put. Fix it by exporting and using a common cleanup helper. (cherry picked from commit 484de39fa5f5b7bd0c5f2e2c5265167250ef7501)