In the Linux kernel, the following vulnerability has been resolved: drm/i915/gt: Fix potential UAF by revoke of fence registers CI has been sporadically reporting the following issue triggered by igt@i915_selftest@live@hangcheck on ADL-P and similar machines: <6> [414.049203] i915: Running intel_hangcheck_live_selftests/igt_reset_evict_fence ... <6> [414.068804] i915 0000:00:02.0: [drm] GT0: GUC: submission enabled <6> [414.068812] i915 0000:00:02.0: [drm] GT0: GUC: SLPC enabled <3> [414.070354] Unable to pin Y-tiled fence; err:-4 <3> [414.071282] i915_vma_revoke_fence:301 GEM_BUG_ON(!i915_active_is_idle(&fence->active)) ... <4>[ 609.603992] ------------[ cut here ]------------ <2>[ 609.603995] kernel BUG at drivers/gpu/drm/i915/gt/intel_ggtt_fencing.c:301! <4>[ 609.604003] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI <4>[ 609.604006] CPU: 0 PID: 268 Comm: kworker/u64:3 Tainted: G U W 6.9.0-CI_DRM_14785-g1ba62f8cea9c+ #1 <4>[ 609.604008] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-P DDR4 RVP, BIOS RPLPFWI1.R00.4035.A00.2301200723 01/20/2023 <4>[ 609.604010] Workqueue: i915 __i915_gem_free_work [i915] <4>[ 609.604149] RIP: 0010:i915_vma_revoke_fence+0x187/0x1f0 [i915] ... <4>[ 609.604271] Call Trace: <4>[ 609.604273] <TASK> ... <4>[ 609.604716] __i915_vma_evict+0x2e9/0x550 [i915] <4>[ 609.604852] __i915_vma_unbind+0x7c/0x160 [i915] <4>[ 609.604977] force_unbind+0x24/0xa0 [i915] <4>[ 609.605098] i915_vma_destroy+0x2f/0xa0 [i915] <4>[ 609.605210] __i915_gem_object_pages_fini+0x51/0x2f0 [i915] <4>[ 609.605330] __i915_gem_free_objects.isra.0+0x6a/0xc0 [i915] <4>[ 609.605440] process_scheduled_works+0x351/0x690 ... In the past, there were similar failures reported by CI from other IGT tests, observed on other platforms. Before commit 63baf4f3d587 ("drm/i915/gt: Only wait for GPU activity before unbinding a GGTT fence"), i915_vma_revoke_fence() was waiting for idleness of vma->active via fence_update(). That commit introduced vma->fence->active in order for the fence_update() to be able to wait selectively on that one instead of vma->active since only idleness of fence registers was needed. But then, another commit 0d86ee35097a ("drm/i915/gt: Make fence revocation unequivocal") replaced the call to fence_update() in i915_vma_revoke_fence() with only fence_write(), and also added that GEM_BUG_ON(!i915_active_is_idle(&fence->active)) in front. No justification was provided on why we might then expect idleness of vma->fence->active without first waiting on it. The issue can be potentially caused by a race among revocation of fence registers on one side and sequential execution of signal callbacks invoked on completion of a request that was using them on the other, still processed in parallel to revocation of those fence registers. Fix it by waiting for idleness of vma->fence->active in i915_vma_revoke_fence(). (cherry picked from commit 24bb052d3dd499c5956abad5f7d8e4fd07da7fb1)

In the Linux kernel, the following vulnerability has been resolved: cachefiles: Set object to close if ondemand_id < 0 in copen If copen is maliciously called in the user mode, it may delete the request corresponding to the random id. And the request may have not been read yet. Note that when the object is set to reopen, the open request will be done with the still reopen state in above case. As a result, the request corresponding to this object is always skipped in select_req function, so the read request is never completed and blocks other process. Fix this issue by simply set object to close if its id < 0 in copen.

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

In the Linux kernel, the following vulnerability has been resolved: uprobe: avoid out-of-bounds memory access of fetching args Uprobe needs to fetch args into a percpu buffer, and then copy to ring buffer to avoid non-atomic context problem. Sometimes user-space strings, arrays can be very large, but the size of percpu buffer is only page size. And store_trace_args() won't check whether these data exceeds a single page or not, caused out-of-bounds memory access. It could be reproduced by following steps: 1. build kernel with CONFIG_KASAN enabled 2. save follow program as test.c ``` \#include <stdio.h> \#include <stdlib.h> \#include <string.h> // If string length large than MAX_STRING_SIZE, the fetch_store_strlen() // will return 0, cause __get_data_size() return shorter size, and // store_trace_args() will not trigger out-of-bounds access. // So make string length less than 4096. \#define STRLEN 4093 void generate_string(char *str, int n) { int i; for (i = 0; i < n; ++i) { char c = i % 26 + 'a'; str[i] = c; } str[n-1] = '\0'; } void print_string(char *str) { printf("%s\n", str); } int main() { char tmp[STRLEN]; generate_string(tmp, STRLEN); print_string(tmp); return 0; } ``` 3. compile program `gcc -o test test.c` 4. get the offset of `print_string()` ``` objdump -t test | grep -w print_string 0000000000401199 g F .text 000000000000001b print_string ``` 5. configure uprobe with offset 0x1199 ``` off=0x1199 cd /sys/kernel/debug/tracing/ echo "p /root/test:${off} arg1=+0(%di):ustring arg2=\$comm arg3=+0(%di):ustring" > uprobe_events echo 1 > events/uprobes/enable echo 1 > tracing_on ``` 6. run `test`, and kasan will report error. ================================================================== BUG: KASAN: use-after-free in strncpy_from_user+0x1d6/0x1f0 Write of size 8 at addr ffff88812311c004 by task test/499CPU: 0 UID: 0 PID: 499 Comm: test Not tainted 6.12.0-rc3+ #18 Hardware name: Red Hat KVM, BIOS 1.16.0-4.al8 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x55/0x70 print_address_description.constprop.0+0x27/0x310 kasan_report+0x10f/0x120 ? strncpy_from_user+0x1d6/0x1f0 strncpy_from_user+0x1d6/0x1f0 ? rmqueue.constprop.0+0x70d/0x2ad0 process_fetch_insn+0xb26/0x1470 ? __pfx_process_fetch_insn+0x10/0x10 ? _raw_spin_lock+0x85/0xe0 ? __pfx__raw_spin_lock+0x10/0x10 ? __pte_offset_map+0x1f/0x2d0 ? unwind_next_frame+0xc5f/0x1f80 ? arch_stack_walk+0x68/0xf0 ? is_bpf_text_address+0x23/0x30 ? kernel_text_address.part.0+0xbb/0xd0 ? __kernel_text_address+0x66/0xb0 ? unwind_get_return_address+0x5e/0xa0 ? __pfx_stack_trace_consume_entry+0x10/0x10 ? arch_stack_walk+0xa2/0xf0 ? _raw_spin_lock_irqsave+0x8b/0xf0 ? __pfx__raw_spin_lock_irqsave+0x10/0x10 ? depot_alloc_stack+0x4c/0x1f0 ? _raw_spin_unlock_irqrestore+0xe/0x30 ? stack_depot_save_flags+0x35d/0x4f0 ? kasan_save_stack+0x34/0x50 ? kasan_save_stack+0x24/0x50 ? mutex_lock+0x91/0xe0 ? __pfx_mutex_lock+0x10/0x10 prepare_uprobe_buffer.part.0+0x2cd/0x500 uprobe_dispatcher+0x2c3/0x6a0 ? __pfx_uprobe_dispatcher+0x10/0x10 ? __kasan_slab_alloc+0x4d/0x90 handler_chain+0xdd/0x3e0 handle_swbp+0x26e/0x3d0 ? __pfx_handle_swbp+0x10/0x10 ? uprobe_pre_sstep_notifier+0x151/0x1b0 irqentry_exit_to_user_mode+0xe2/0x1b0 asm_exc_int3+0x39/0x40 RIP: 0033:0x401199 Code: 01 c2 0f b6 45 fb 88 02 83 45 fc 01 8b 45 fc 3b 45 e4 7c b7 8b 45 e4 48 98 48 8d 50 ff 48 8b 45 e8 48 01 d0 ce RSP: 002b:00007ffdf00576a8 EFLAGS: 00000206 RAX: 00007ffdf00576b0 RBX: 0000000000000000 RCX: 0000000000000ff2 RDX: 0000000000000ffc RSI: 0000000000000ffd RDI: 00007ffdf00576b0 RBP: 00007ffdf00586b0 R08: 00007feb2f9c0d20 R09: 00007feb2f9c0d20 R10: 0000000000000001 R11: 0000000000000202 R12: 0000000000401040 R13: 00007ffdf0058780 R14: 0000000000000000 R15: 0000000000000000 </TASK> This commit enforces the buffer's maxlen less than a page-size to avoid store_trace_args() out-of-memory access.

In the Linux kernel, the following vulnerability has been resolved: greybus: Fix use-after-free bug in gb_interface_release due to race condition. In gb_interface_create, &intf->mode_switch_completion is bound with gb_interface_mode_switch_work. Then it will be started by gb_interface_request_mode_switch. Here is the relevant code. if (!queue_work(system_long_wq, &intf->mode_switch_work)) { ... } If we call gb_interface_release to make cleanup, there may be an unfinished work. This function will call kfree to free the object "intf". However, if gb_interface_mode_switch_work is scheduled to run after kfree, it may cause use-after-free error as gb_interface_mode_switch_work will use the object "intf". The possible execution flow that may lead to the issue is as follows: CPU0 CPU1 | gb_interface_create | gb_interface_request_mode_switch gb_interface_release | kfree(intf) (free) | | gb_interface_mode_switch_work | mutex_lock(&intf->mutex) (use) Fix it by canceling the work before kfree.

In the Linux kernel, the following vulnerability has been resolved: ima: Fix use-after-free on a dentry's dname.name ->d_name.name can change on rename and the earlier value can be freed; there are conditions sufficient to stabilize it (->d_lock on dentry, ->d_lock on its parent, ->i_rwsem exclusive on the parent's inode, rename_lock), but none of those are met at any of the sites. Take a stable snapshot of the name instead.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix use-after-free in crypt_message when using async crypto The CVE-2024-50047 fix removed asynchronous crypto handling from crypt_message(), assuming all crypto operations are synchronous. However, when hardware crypto accelerators are used, this can cause use-after-free crashes: crypt_message() // Allocate the creq buffer containing the req creq = smb2_get_aead_req(..., &req); // Async encryption returns -EINPROGRESS immediately rc = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req); // Free creq while async operation is still in progress kvfree_sensitive(creq, ...); Hardware crypto modules often implement async AEAD operations for performance. When crypto_aead_encrypt/decrypt() returns -EINPROGRESS, the operation completes asynchronously. Without crypto_wait_req(), the function immediately frees the request buffer, leading to crashes when the driver later accesses the freed memory. This results in a use-after-free condition when the hardware crypto driver later accesses the freed request structure, leading to kernel crashes with NULL pointer dereferences. The issue occurs because crypto_alloc_aead() with mask=0 doesn't guarantee synchronous operation. Even without CRYPTO_ALG_ASYNC in the mask, async implementations can be selected. Fix by restoring the async crypto handling: - DECLARE_CRYPTO_WAIT(wait) for completion tracking - aead_request_set_callback() for async completion notification - crypto_wait_req() to wait for operation completion This ensures the request buffer isn't freed until the crypto operation completes, whether synchronous or asynchronous, while preserving the CVE-2024-50047 fix.

A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be exploited to achieve local privilege escalation. Both io_install_fixed_file and its callers call fput in a file in case of an error, causing a reference underflow which leads to a use-after-free vulnerability. We recommend upgrading past commit 9d94c04c0db024922e886c9fd429659f22f48ea4.

In the Linux kernel, the following vulnerability has been resolved: sctp: detect and prevent references to a freed transport in sendmsg sctp_sendmsg() re-uses associations and transports when possible by doing a lookup based on the socket endpoint and the message destination address, and then sctp_sendmsg_to_asoc() sets the selected transport in all the message chunks to be sent. There's a possible race condition if another thread triggers the removal of that selected transport, for instance, by explicitly unbinding an address with setsockopt(SCTP_SOCKOPT_BINDX_REM), after the chunks have been set up and before the message is sent. This can happen if the send buffer is full, during the period when the sender thread temporarily releases the socket lock in sctp_wait_for_sndbuf(). This causes the access to the transport data in sctp_outq_select_transport(), when the association outqueue is flushed, to result in a use-after-free read. This change avoids this scenario by having sctp_transport_free() signal the freeing of the transport, tagging it as "dead". In order to do this, the patch restores the "dead" bit in struct sctp_transport, which was removed in commit 47faa1e4c50e ("sctp: remove the dead field of sctp_transport"). Then, in the scenario where the sender thread has released the socket lock in sctp_wait_for_sndbuf(), the bit is checked again after re-acquiring the socket lock to detect the deletion. This is done while holding a reference to the transport to prevent it from being freed in the process. If the transport was deleted while the socket lock was relinquished, sctp_sendmsg_to_asoc() will return -EAGAIN to let userspace retry the send. The bug was found by a private syzbot instance (see the error report [1] and the C reproducer that triggers it [2]).

A use-after-free flaw was found in the io_uring in Linux kernel, where a local attacker with a user privilege could cause a denial of service problem on the system The issue results from the lack of validating the existence of an object prior to performing operations on the object by not incrementing the file reference counter while in use. The highest threat from this vulnerability is to data integrity, confidentiality and system availability.

In the Linux kernel, the following vulnerability has been resolved: i2c: Fix a potential use after free Free the adap structure only after we are done using it. This patch just moves the put_device() down a bit to avoid the use after free. [wsa: added comment to the code, added Fixes tag]

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

In the Linux kernel, the following vulnerability has been resolved: wifi: rtlwifi: remove unused check_buddy_priv Commit 2461c7d60f9f ("rtlwifi: Update header file") introduced a global list of private data structures. Later on, commit 26634c4b1868 ("rtlwifi Modify existing bits to match vendor version 2013.02.07") started adding the private data to that list at probe time and added a hook, check_buddy_priv to find the private data from a similar device. However, that function was never used. Besides, though there is a lock for that list, it is never used. And when the probe fails, the private data is never removed from the list. This would cause a second probe to access freed memory. Remove the unused hook, structures and members, which will prevent the potential race condition on the list and its corruption during a second probe when probe fails.

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

In the Linux kernel, the following vulnerability has been resolved: pps: Fix a use-after-free On a board running ntpd and gpsd, I'm seeing a consistent use-after-free in sys_exit() from gpsd when rebooting: pps pps1: removed ------------[ cut here ]------------ kobject: '(null)' (00000000db4bec24): is not initialized, yet kobject_put() is being called. WARNING: CPU: 2 PID: 440 at lib/kobject.c:734 kobject_put+0x120/0x150 CPU: 2 UID: 299 PID: 440 Comm: gpsd Not tainted 6.11.0-rc6-00308-gb31c44928842 #1 Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : kobject_put+0x120/0x150 lr : kobject_put+0x120/0x150 sp : ffffffc0803d3ae0 x29: ffffffc0803d3ae0 x28: ffffff8042dc9738 x27: 0000000000000001 x26: 0000000000000000 x25: ffffff8042dc9040 x24: ffffff8042dc9440 x23: ffffff80402a4620 x22: ffffff8042ef4bd0 x21: ffffff80405cb600 x20: 000000000008001b x19: ffffff8040b3b6e0 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 696e6920746f6e20 x14: 7369203a29343263 x13: 205d303434542020 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: kobject_put+0x120/0x150 cdev_put+0x20/0x3c __fput+0x2c4/0x2d8 ____fput+0x1c/0x38 task_work_run+0x70/0xfc do_exit+0x2a0/0x924 do_group_exit+0x34/0x90 get_signal+0x7fc/0x8c0 do_signal+0x128/0x13b4 do_notify_resume+0xdc/0x160 el0_svc+0xd4/0xf8 el0t_64_sync_handler+0x140/0x14c el0t_64_sync+0x190/0x194 ---[ end trace 0000000000000000 ]--- ...followed by more symptoms of corruption, with similar stacks: refcount_t: underflow; use-after-free. kernel BUG at lib/list_debug.c:62! Kernel panic - not syncing: Oops - BUG: Fatal exception This happens because pps_device_destruct() frees the pps_device with the embedded cdev immediately after calling cdev_del(), but, as the comment above cdev_del() notes, fops for previously opened cdevs are still callable even after cdev_del() returns. I think this bug has always been there: I can't explain why it suddenly started happening every time I reboot this particular board. In commit d953e0e837e6 ("pps: Fix a use-after free bug when unregistering a source."), George Spelvin suggested removing the embedded cdev. That seems like the simplest way to fix this, so I've implemented his suggestion, using __register_chrdev() with pps_idr becoming the source of truth for which minor corresponds to which device. But now that pps_idr defines userspace visibility instead of cdev_add(), we need to be sure the pps->dev refcount can't reach zero while userspace can still find it again. So, the idr_remove() call moves to pps_unregister_cdev(), and pps_idr now holds a reference to pps->dev. pps_core: source serial1 got cdev (251:1) <...> pps pps1: removed pps_core: unregistering pps1 pps_core: deallocating pps1

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

The block subsystem in the Linux kernel before 5.2 has a use-after-free that can lead to arbitrary code execution in the kernel context and privilege escalation, aka CID-c3e2219216c9. This is related to blk_mq_free_rqs and blk_cleanup_queue.

In the Linux kernel, the following vulnerability has been resolved: media: uvcvideo: Remove dangling pointers When an async control is written, we copy a pointer to the file handle that started the operation. That pointer will be used when the device is done. Which could be anytime in the future. If the user closes that file descriptor, its structure will be freed, and there will be one dangling pointer per pending async control, that the driver will try to use. Clean all the dangling pointers during release(). To avoid adding a performance penalty in the most common case (no async operation), a counter has been introduced with some logic to make sure that it is properly handled.

In the Linux kernel, the following vulnerability has been resolved: PCI/ASPM: Fix link state exit during switch upstream function removal Before 456d8aa37d0f ("PCI/ASPM: Disable ASPM on MFD function removal to avoid use-after-free"), we would free the ASPM link only after the last function on the bus pertaining to the given link was removed. That was too late. If function 0 is removed before sibling function, link->downstream would point to free'd memory after. After above change, we freed the ASPM parent link state upon any function removal on the bus pertaining to a given link. That is too early. If the link is to a PCIe switch with MFD on the upstream port, then removing functions other than 0 first would free a link which still remains parent_link to the remaining downstream ports. The resulting GPFs are especially frequent during hot-unplug, because pciehp removes devices on the link bus in reverse order. On that switch, function 0 is the virtual P2P bridge to the internal bus. Free exactly when function 0 is removed -- before the parent link is obsolete, but after all subordinate links are gone. [kwilczynski: commit log]

In the Linux kernel, the following vulnerability has been resolved: i3c: dw: Fix use-after-free in dw_i3c_master driver due to race condition In dw_i3c_common_probe, &master->hj_work is bound with dw_i3c_hj_work. And dw_i3c_master_irq_handler can call dw_i3c_master_irq_handle_ibis function to start the work. If we remove the module which will call dw_i3c_common_remove to make cleanup, it will free master->base through i3c_master_unregister while the work mentioned above will be used. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | dw_i3c_hj_work dw_i3c_common_remove | i3c_master_unregister(&master->base) | device_unregister(&master->dev) | device_release | //free master->base | | i3c_master_do_daa(&master->base) | //use master->base Fix it by ensuring that the work is canceled before proceeding with the cleanup in dw_i3c_common_remove.

In the Linux kernel, the following vulnerability has been resolved: tls: separate no-async decryption request handling from async If we're not doing async, the handling is much simpler. There's no reference counting, we just need to wait for the completion to wake us up and return its result. We should preferably also use a separate crypto_wait. I'm not seeing a UAF as I did in the past, I think aec7961916f3 ("tls: fix race between async notify and socket close") took care of it. This will make the next fix easier.

In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix read pointer after free in ath12k_mac_assign_vif_to_vdev() In ath12k_mac_assign_vif_to_vdev(), if arvif is created on a different radio, it gets deleted from that radio through a call to ath12k_mac_unassign_link_vif(). This action frees the arvif pointer. Subsequently, there is a check involving arvif, which will result in a read-after-free scenario. Fix this by moving this check after arvif is again assigned via call to ath12k_mac_assign_link_vif(). Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1

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

In the Linux kernel, the following vulnerability has been resolved: drm/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req() While receiving an MST up request message from one thread in drm_dp_mst_handle_up_req(), the MST topology could be removed from another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL. This could lead to a NULL deref/use-after-free of mst_primary in drm_dp_mst_handle_up_req(). Avoid the above by holding a reference for mst_primary in drm_dp_mst_handle_up_req() while it's used. v2: Fix kfreeing the request if getting an mst_primary reference fails.

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

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

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

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix potential out-of-bounds memory access in nilfs_find_entry() Syzbot reported that when searching for records in a directory where the inode's i_size is corrupted and has a large value, memory access outside the folio/page range may occur, or a use-after-free bug may be detected if KASAN is enabled. This is because nilfs_last_byte(), which is called by nilfs_find_entry() and others to calculate the number of valid bytes of directory data in a page from i_size and the page index, loses the upper 32 bits of the 64-bit size information due to an inappropriate type of local variable to which the i_size value is assigned. This caused a large byte offset value due to underflow in the end address calculation in the calling nilfs_find_entry(), resulting in memory access that exceeds the folio/page size. Fix this issue by changing the type of the local variable causing the bit loss from "unsigned int" to "u64". The return value of nilfs_last_byte() is also of type "unsigned int", but it is truncated so as not to exceed PAGE_SIZE and no bit loss occurs, so no change is required.

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix use-after-free in btrfs_encoded_read_endio() Shinichiro reported the following use-after free that sometimes is happening in our CI system when running fstests' btrfs/284 on a TCMU runner device: BUG: KASAN: slab-use-after-free in lock_release+0x708/0x780 Read of size 8 at addr ffff888106a83f18 by task kworker/u80:6/219 CPU: 8 UID: 0 PID: 219 Comm: kworker/u80:6 Not tainted 6.12.0-rc6-kts+ #15 Hardware name: Supermicro Super Server/X11SPi-TF, BIOS 3.3 02/21/2020 Workqueue: btrfs-endio btrfs_end_bio_work [btrfs] Call Trace: <TASK> dump_stack_lvl+0x6e/0xa0 ? lock_release+0x708/0x780 print_report+0x174/0x505 ? lock_release+0x708/0x780 ? __virt_addr_valid+0x224/0x410 ? lock_release+0x708/0x780 kasan_report+0xda/0x1b0 ? lock_release+0x708/0x780 ? __wake_up+0x44/0x60 lock_release+0x708/0x780 ? __pfx_lock_release+0x10/0x10 ? __pfx_do_raw_spin_lock+0x10/0x10 ? lock_is_held_type+0x9a/0x110 _raw_spin_unlock_irqrestore+0x1f/0x60 __wake_up+0x44/0x60 btrfs_encoded_read_endio+0x14b/0x190 [btrfs] btrfs_check_read_bio+0x8d9/0x1360 [btrfs] ? lock_release+0x1b0/0x780 ? trace_lock_acquire+0x12f/0x1a0 ? __pfx_btrfs_check_read_bio+0x10/0x10 [btrfs] ? process_one_work+0x7e3/0x1460 ? lock_acquire+0x31/0xc0 ? process_one_work+0x7e3/0x1460 process_one_work+0x85c/0x1460 ? __pfx_process_one_work+0x10/0x10 ? assign_work+0x16c/0x240 worker_thread+0x5e6/0xfc0 ? __pfx_worker_thread+0x10/0x10 kthread+0x2c3/0x3a0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 3661: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0xaa/0xb0 btrfs_encoded_read_regular_fill_pages+0x16c/0x6d0 [btrfs] send_extent_data+0xf0f/0x24a0 [btrfs] process_extent+0x48a/0x1830 [btrfs] changed_cb+0x178b/0x2ea0 [btrfs] btrfs_ioctl_send+0x3bf9/0x5c20 [btrfs] _btrfs_ioctl_send+0x117/0x330 [btrfs] btrfs_ioctl+0x184a/0x60a0 [btrfs] __x64_sys_ioctl+0x12e/0x1a0 do_syscall_64+0x95/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 3661: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x70 __kasan_slab_free+0x4f/0x70 kfree+0x143/0x490 btrfs_encoded_read_regular_fill_pages+0x531/0x6d0 [btrfs] send_extent_data+0xf0f/0x24a0 [btrfs] process_extent+0x48a/0x1830 [btrfs] changed_cb+0x178b/0x2ea0 [btrfs] btrfs_ioctl_send+0x3bf9/0x5c20 [btrfs] _btrfs_ioctl_send+0x117/0x330 [btrfs] btrfs_ioctl+0x184a/0x60a0 [btrfs] __x64_sys_ioctl+0x12e/0x1a0 do_syscall_64+0x95/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff888106a83f00 which belongs to the cache kmalloc-rnd-07-96 of size 96 The buggy address is located 24 bytes inside of freed 96-byte region [ffff888106a83f00, ffff888106a83f60) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888106a83800 pfn:0x106a83 flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff) page_type: f5(slab) raw: 0017ffffc0000000 ffff888100053680 ffffea0004917200 0000000000000004 raw: ffff888106a83800 0000000080200019 00000001f5000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888106a83e00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888106a83e80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888106a83f00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff888106a83f80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888106a84000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== Further analyzing the trace and ---truncated---

In the Linux kernel, the following vulnerability has been resolved: brd: defer automatic disk creation until module initialization succeeds My colleague Wupeng found the following problems during fault injection: BUG: unable to handle page fault for address: fffffbfff809d073 PGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__asan_load8+0x4c/0xa0 ... Call Trace: <TASK> blkdev_put_whole+0x41/0x70 bdev_release+0x1a3/0x250 blkdev_release+0x11/0x20 __fput+0x1d7/0x4a0 task_work_run+0xfc/0x180 syscall_exit_to_user_mode+0x1de/0x1f0 do_syscall_64+0x6b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e loop_init() is calling loop_add() after __register_blkdev() succeeds and is ignoring disk_add() failure from loop_add(), for loop_add() failure is not fatal and successfully created disks are already visible to bdev_open(). brd_init() is currently calling brd_alloc() before __register_blkdev() succeeds and is releasing successfully created disks when brd_init() returns an error. This can cause UAF for the latter two case: case 1: T1: modprobe brd brd_init brd_alloc(0) // success add_disk disk_scan_partitions bdev_file_open_by_dev // alloc file fput // won't free until back to userspace brd_alloc(1) // failed since mem alloc error inject // error path for modprobe will release code segment // back to userspace __fput blkdev_release bdev_release blkdev_put_whole bdev->bd_disk->fops->release // fops is freed now, UAF! case 2: T1: T2: modprobe brd brd_init brd_alloc(0) // success open(/dev/ram0) brd_alloc(1) // fail // error path for modprobe close(/dev/ram0) ... /* UAF! */ bdev->bd_disk->fops->release Fix this problem by following what loop_init() does. Besides, reintroduce brd_devices_mutex to help serialize modifications to brd_list.

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

In the Linux kernel, the following vulnerability has been resolved: 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: drm: zynqmp_kms: Unplug DRM device before removal Prevent userspace accesses to the DRM device from causing use-after-frees by unplugging the device before we remove it. This causes any further userspace accesses to result in an error without further calls into this driver's internals.

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

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

In the Linux kernel, the following vulnerability has been resolved: af_packet: avoid erroring out after sock_init_data() in packet_create() After sock_init_data() the allocated sk object is attached to the provided sock object. On error, packet_create() frees the sk object leaving the dangling pointer in the sock object on return. Some other code may try to use this pointer and cause use-after-free.

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix UAF via mismatching bpf_prog/attachment RCU flavors Uprobes always use bpf_prog_run_array_uprobe() under tasks-trace-RCU protection. But it is possible to attach a non-sleepable BPF program to a uprobe, and non-sleepable BPF programs are freed via normal RCU (see __bpf_prog_put_noref()). This leads to UAF of the bpf_prog because a normal RCU grace period does not imply a tasks-trace-RCU grace period. Fix it by explicitly waiting for a tasks-trace-RCU grace period after removing the attachment of a bpf_prog to a perf_event.

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

In the Linux kernel, the following vulnerability has been resolved: kunit: string-stream: Fix a UAF bug in kunit_init_suite() In kunit_debugfs_create_suite(), if alloc_string_stream() fails in the kunit_suite_for_each_test_case() loop, the "suite->log = stream" has assigned before, and the error path only free the suite->log's stream memory but not set it to NULL, so the later string_stream_clear() of suite->log in kunit_init_suite() will cause below UAF bug. Set stream pointer to NULL after free to fix it. Unable to handle kernel paging request at virtual address 006440150000030d Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [006440150000030d] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: iio_test_gts industrialio_gts_helper cfg80211 rfkill ipv6 [last unloaded: iio_test_gts] CPU: 5 UID: 0 PID: 6253 Comm: modprobe Tainted: G B W N 6.12.0-rc4+ #458 Tainted: [B]=BAD_PAGE, [W]=WARN, [N]=TEST Hardware name: linux,dummy-virt (DT) pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : string_stream_clear+0x54/0x1ac lr : string_stream_clear+0x1a8/0x1ac sp : ffffffc080b47410 x29: ffffffc080b47410 x28: 006440550000030d x27: ffffff80c96b5e98 x26: ffffff80c96b5e80 x25: ffffffe461b3f6c0 x24: 0000000000000003 x23: ffffff80c96b5e88 x22: 1ffffff019cdf4fc x21: dfffffc000000000 x20: ffffff80ce6fa7e0 x19: 032202a80000186d x18: 0000000000001840 x17: 0000000000000000 x16: 0000000000000000 x15: ffffffe45c355cb4 x14: ffffffe45c35589c x13: ffffffe45c03da78 x12: ffffffb810168e75 x11: 1ffffff810168e74 x10: ffffffb810168e74 x9 : dfffffc000000000 x8 : 0000000000000004 x7 : 0000000000000003 x6 : 0000000000000001 x5 : ffffffc080b473a0 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000001 x1 : ffffffe462fbf620 x0 : dfffffc000000000 Call trace: string_stream_clear+0x54/0x1ac __kunit_test_suites_init+0x108/0x1d8 kunit_exec_run_tests+0xb8/0x100 kunit_module_notify+0x400/0x55c notifier_call_chain+0xfc/0x3b4 blocking_notifier_call_chain+0x68/0x9c do_init_module+0x24c/0x5c8 load_module+0x4acc/0x4e90 init_module_from_file+0xd4/0x128 idempotent_init_module+0x2d4/0x57c __arm64_sys_finit_module+0xac/0x100 invoke_syscall+0x6c/0x258 el0_svc_common.constprop.0+0x160/0x22c do_el0_svc+0x44/0x5c el0_svc+0x48/0xb8 el0t_64_sync_handler+0x13c/0x158 el0t_64_sync+0x190/0x194 Code: f9400753 d2dff800 f2fbffe0 d343fe7c (38e06b80) ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Oops: Fatal exception

In the Linux kernel, the following vulnerability has been resolved: powerpc/mm/fault: Fix kfence page fault reporting copy_from_kernel_nofault() can be called when doing read of /proc/kcore. /proc/kcore can have some unmapped kfence objects which when read via copy_from_kernel_nofault() can cause page faults. Since *_nofault() functions define their own fixup table for handling fault, use that instead of asking kfence to handle such faults. Hence we search the exception tables for the nip which generated the fault. If there is an entry then we let the fixup table handler handle the page fault by returning an error from within ___do_page_fault(). This can be easily triggered if someone tries to do dd from /proc/kcore. eg. dd if=/proc/kcore of=/dev/null bs=1M Some example false negatives: =============================== BUG: KFENCE: invalid read in copy_from_kernel_nofault+0x9c/0x1a0 Invalid read at 0xc0000000fdff0000: copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec BUG: KFENCE: use-after-free read in copy_from_kernel_nofault+0x9c/0x1a0 Use-after-free read at 0xc0000000fe050000 (in kfence-#2): copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec

In the Linux kernel, the following vulnerability has been resolved: can: hi311x: hi3110_can_ist(): fix potential use-after-free The commit a22bd630cfff ("can: hi311x: do not report txerr and rxerr during bus-off") removed the reporting of rxerr and txerr even in case of correct operation (i. e. not bus-off). The error count information added to the CAN frame after netif_rx() is a potential use after free, since there is no guarantee that the skb is in the same state. It might be freed or reused. Fix the issue by postponing the netif_rx() call in case of txerr and rxerr reporting.

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: Fix PCI domain ID release in pci_epc_destroy() pci_epc_destroy() invokes pci_bus_release_domain_nr() to release the PCI domain ID, but there are two issues: - 'epc->dev' is passed to pci_bus_release_domain_nr() which was already freed by device_unregister(), leading to a use-after-free issue. - Domain ID corresponds to the EPC device parent, so passing 'epc->dev' is also wrong. Fix these issues by passing 'epc->dev.parent' to pci_bus_release_domain_nr() and also do it before device_unregister(). [mani: reworded subject and description]

In the Linux kernel, the following vulnerability has been resolved: net: inet6: do not leave a dangling sk pointer in inet6_create() sock_init_data() attaches the allocated sk pointer to the provided sock object. If inet6_create() fails later, the sk object is released, but the sock object retains the dangling sk pointer, which may cause use-after-free later. Clear the sock sk pointer on error.

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

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

In the Linux kernel, the following vulnerability has been resolved: drm/xe/reg_sr: Remove register pool That pool implementation doesn't really work: if the krealloc happens to move the memory and return another address, the entries in the xarray become invalid, leading to use-after-free later: BUG: KASAN: slab-use-after-free in xe_reg_sr_apply_mmio+0x570/0x760 [xe] Read of size 4 at addr ffff8881244b2590 by task modprobe/2753 Allocated by task 2753: kasan_save_stack+0x39/0x70 kasan_save_track+0x14/0x40 kasan_save_alloc_info+0x37/0x60 __kasan_kmalloc+0xc3/0xd0 __kmalloc_node_track_caller_noprof+0x200/0x6d0 krealloc_noprof+0x229/0x380 Simplify the code to fix the bug. A better pooling strategy may be added back later if needed. (cherry picked from commit e5283bd4dfecbd3335f43b62a68e24dae23f59e4)

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: avoid leaving dangling sk pointer in rfcomm_sock_alloc() bt_sock_alloc() attaches allocated sk object to the provided sock object. If rfcomm_dlc_alloc() fails, we release the sk object, but leave the dangling pointer in the sock object, which may cause use-after-free. Fix this by swapping calls to bt_sock_alloc() and rfcomm_dlc_alloc().

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

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

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