In the Linux kernel, the following vulnerability has been resolved: aoe: fix the potential use-after-free problem in more places For fixing CVE-2023-6270, f98364e92662 ("aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts") makes tx() calling dev_put() instead of doing in aoecmd_cfg_pkts(). It avoids that the tx() runs into use-after-free. Then Nicolai Stange found more places in aoe have potential use-after-free problem with tx(). e.g. revalidate(), aoecmd_ata_rw(), resend(), probe() and aoecmd_cfg_rsp(). Those functions also use aoenet_xmit() to push packet to tx queue. So they should also use dev_hold() to increase the refcnt of skb->dev. On the other hand, moving dev_put() to tx() causes that the refcnt of skb->dev be reduced to a negative value, because corresponding dev_hold() are not called in revalidate(), aoecmd_ata_rw(), resend(), probe(), and aoecmd_cfg_rsp(). This patch fixed this issue.

In the Linux kernel, the following vulnerability has been resolved: drm/stm: Avoid use-after-free issues with crtc and plane ltdc_load() calls functions drm_crtc_init_with_planes(), drm_universal_plane_init() and drm_encoder_init(). These functions should not be called with parameters allocated with devm_kzalloc() to avoid use-after-free issues [1]. Use allocations managed by the DRM framework. Found by Linux Verification Center (linuxtesting.org). [1] https://lore.kernel.org/lkml/u366i76e3qhh3ra5oxrtngjtm2u5lterkekcz6y2jkndhuxzli@diujon4h7qwb/

Use After Free vulnerability in nfc sockets in the Linux Kernel before 5.12.4 allows local attackers to elevate their privileges. In typical configurations, the issue can only be triggered by a privileged local user with the CAP_NET_RAW capability.

An issue was discovered in the Linux kernel before 4.14.16. There is a use-after-free in net/sctp/socket.c for a held lock after a peel off, aka CID-a0ff660058b8.

In the Linux kernel, the following vulnerability has been resolved: vhost_vdpa: assign irq bypass producer token correctly We used to call irq_bypass_unregister_producer() in vhost_vdpa_setup_vq_irq() which is problematic as we don't know if the token pointer is still valid or not. Actually, we use the eventfd_ctx as the token so the life cycle of the token should be bound to the VHOST_SET_VRING_CALL instead of vhost_vdpa_setup_vq_irq() which could be called by set_status(). Fixing this by setting up irq bypass producer's token when handling VHOST_SET_VRING_CALL and un-registering the producer before calling vhost_vring_ioctl() to prevent a possible use after free as eventfd could have been released in vhost_vring_ioctl(). And such registering and unregistering will only be done if DRIVER_OK is set.

A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. When fw_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. We recommend upgrading past commit 76e42ae831991c828cffa8c37736ebfb831ad5ec.

Use After Free vulnerability in Linux Linux kernel kernel on Linux, x86, ARM (bluetooth modules) allows Local Execution of Code. This vulnerability is associated with program files https://gitee.Com/anolis/cloud-kernel/blob/devel-5.10/net/bluetooth/af_bluetooth.C. This issue affects Linux kernel: from v2.6.12-rc2 before v6.8-rc1.

In the Linux kernel, the following vulnerability has been resolved: scsi: elx: libefc: Fix potential use after free in efc_nport_vport_del() The kref_put() function will call nport->release if the refcount drops to zero. The nport->release release function is _efc_nport_free() which frees "nport". But then we dereference "nport" on the next line which is a use after free. Re-order these lines to avoid the use after free.

In the Linux kernel, the following vulnerability has been resolved: wifi: rtw88: always wait for both firmware loading attempts In 'rtw_wait_firmware_completion()', always wait for both (regular and wowlan) firmware loading attempts. Otherwise if 'rtw_usb_intf_init()' has failed in 'rtw_usb_probe()', 'rtw_usb_disconnect()' may issue 'ieee80211_free_hw()' when one of 'rtw_load_firmware_cb()' (usually the wowlan one) is still in progress, causing UAF detected by KASAN.

An issue was discovered in the Linux kernel through 4.18.8. The vmacache_flush_all function in mm/vmacache.c mishandles sequence number overflows. An attacker can trigger a use-after-free (and possibly gain privileges) via certain thread creation, map, unmap, invalidation, and dereference operations.

In the Linux kernel, the following vulnerability has been resolved: cxl/port: Fix use-after-free, permit out-of-order decoder shutdown In support of investigating an initialization failure report [1], cxl_test was updated to register mock memory-devices after the mock root-port/bus device had been registered. That led to cxl_test crashing with a use-after-free bug with the following signature: cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1 cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1 cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0 1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1 [..] cxld_unregister: cxl decoder14.0: cxl_region_decode_reset: cxl_region region3: mock_decoder_reset: cxl_port port3: decoder3.0 reset 2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1 cxl_endpoint_decoder_release: cxl decoder14.0: [..] cxld_unregister: cxl decoder7.0: 3) cxl_region_decode_reset: cxl_region region3: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI [..] RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core] [..] Call Trace: <TASK> cxl_region_decode_reset+0x69/0x190 [cxl_core] cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x5d/0x60 [cxl_core] At 1) a region has been established with 2 endpoint decoders (7.0 and 14.0). Those endpoints share a common switch-decoder in the topology (3.0). At teardown, 2), decoder14.0 is the first to be removed and hits the "out of order reset case" in the switch decoder. The effect though is that region3 cleanup is aborted leaving it in-tact and referencing decoder14.0. At 3) the second attempt to teardown region3 trips over the stale decoder14.0 object which has long since been deleted. The fix here is to recognize that the CXL specification places no mandate on in-order shutdown of switch-decoders, the driver enforces in-order allocation, and hardware enforces in-order commit. So, rather than fail and leave objects dangling, always remove them. In support of making cxl_region_decode_reset() always succeed, cxl_region_invalidate_memregion() failures are turned into warnings. Crashing the kernel is ok there since system integrity is at risk if caches cannot be managed around physical address mutation events like CXL region destruction. A new device_for_each_child_reverse_from() is added to cleanup port->commit_end after all dependent decoders have been disabled. In other words if decoders are allocated 0->1->2 and disabled 1->2->0 then port->commit_end only decrements from 2 after 2 has been disabled, and it decrements all the way to zero since 1 was disabled previously.

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: btrfs: fix a use-after-free when hitting errors inside btrfs_submit_chunk() [BUG] There is an internal report that KASAN is reporting use-after-free, with the following backtrace: BUG: KASAN: slab-use-after-free in btrfs_check_read_bio+0xa68/0xb70 [btrfs] Read of size 4 at addr ffff8881117cec28 by task kworker/u16:2/45 CPU: 1 UID: 0 PID: 45 Comm: kworker/u16:2 Not tainted 6.11.0-rc2-next-20240805-default+ #76 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 Workqueue: btrfs-endio btrfs_end_bio_work [btrfs] Call Trace: dump_stack_lvl+0x61/0x80 print_address_description.constprop.0+0x5e/0x2f0 print_report+0x118/0x216 kasan_report+0x11d/0x1f0 btrfs_check_read_bio+0xa68/0xb70 [btrfs] process_one_work+0xce0/0x12a0 worker_thread+0x717/0x1250 kthread+0x2e3/0x3c0 ret_from_fork+0x2d/0x70 ret_from_fork_asm+0x11/0x20 Allocated by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 __kasan_slab_alloc+0x7d/0x80 kmem_cache_alloc_noprof+0x16e/0x3e0 mempool_alloc_noprof+0x12e/0x310 bio_alloc_bioset+0x3f0/0x7a0 btrfs_bio_alloc+0x2e/0x50 [btrfs] submit_extent_page+0x4d1/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x50 __kasan_slab_free+0x4b/0x60 kmem_cache_free+0x214/0x5d0 bio_free+0xed/0x180 end_bbio_data_read+0x1cc/0x580 [btrfs] btrfs_submit_chunk+0x98d/0x1880 [btrfs] btrfs_submit_bio+0x33/0x70 [btrfs] submit_one_bio+0xd4/0x130 [btrfs] submit_extent_page+0x3ea/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [CAUSE] Although I cannot reproduce the error, the report itself is good enough to pin down the cause. The call trace is the regular endio workqueue context, but the free-by-task trace is showing that during btrfs_submit_chunk() we already hit a critical error, and is calling btrfs_bio_end_io() to error out. And the original endio function called bio_put() to free the whole bio. This means a double freeing thus causing use-after-free, e.g.: 1. Enter btrfs_submit_bio() with a read bio The read bio length is 128K, crossing two 64K stripes. 2. The first run of btrfs_submit_chunk() 2.1 Call btrfs_map_block(), which returns 64K 2.2 Call btrfs_split_bio() Now there are two bios, one referring to the first 64K, the other referring to the second 64K. 2.3 The first half is submitted. 3. The second run of btrfs_submit_chunk() 3.1 Call btrfs_map_block(), which by somehow failed Now we call btrfs_bio_end_io() to handle the error 3.2 btrfs_bio_end_io() calls the original endio function Which is end_bbio_data_read(), and it calls bio_put() for the original bio. Now the original bio is freed. 4. The submitted first 64K bio finished Now we call into btrfs_check_read_bio() and tries to advance the bio iter. But since the original bio (thus its iter) is already freed, we trigger the above use-after free. And even if the memory is not poisoned/corrupted, we will later call the original endio function, causing a double freeing. [FIX] Instead of calling btrfs_bio_end_io(), call btrfs_orig_bbio_end_io(), which has the extra check on split bios and do the pr ---truncated---

In the Linux kernel, the following vulnerability has been resolved: media: xc2028: avoid use-after-free in load_firmware_cb() syzkaller reported use-after-free in load_firmware_cb() [1]. The reason is because the module allocated a struct tuner in tuner_probe(), and then the module initialization failed, the struct tuner was released. A worker which created during module initialization accesses this struct tuner later, it caused use-after-free. The process is as follows: task-6504 worker_thread tuner_probe <= alloc dvb_frontend [2] ... request_firmware_nowait <= create a worker ... tuner_remove <= free dvb_frontend ... request_firmware_work_func <= the firmware is ready load_firmware_cb <= but now the dvb_frontend has been freed To fix the issue, check the dvd_frontend in load_firmware_cb(), if it is null, report a warning and just return. [1]: ================================================================== BUG: KASAN: use-after-free in load_firmware_cb+0x1310/0x17a0 Read of size 8 at addr ffff8000d7ca2308 by task kworker/2:3/6504 Call trace: load_firmware_cb+0x1310/0x17a0 request_firmware_work_func+0x128/0x220 process_one_work+0x770/0x1824 worker_thread+0x488/0xea0 kthread+0x300/0x430 ret_from_fork+0x10/0x20 Allocated by task 6504: kzalloc tuner_probe+0xb0/0x1430 i2c_device_probe+0x92c/0xaf0 really_probe+0x678/0xcd0 driver_probe_device+0x280/0x370 __device_attach_driver+0x220/0x330 bus_for_each_drv+0x134/0x1c0 __device_attach+0x1f4/0x410 device_initial_probe+0x20/0x30 bus_probe_device+0x184/0x200 device_add+0x924/0x12c0 device_register+0x24/0x30 i2c_new_device+0x4e0/0xc44 v4l2_i2c_new_subdev_board+0xbc/0x290 v4l2_i2c_new_subdev+0xc8/0x104 em28xx_v4l2_init+0x1dd0/0x3770 Freed by task 6504: kfree+0x238/0x4e4 tuner_remove+0x144/0x1c0 i2c_device_remove+0xc8/0x290 __device_release_driver+0x314/0x5fc device_release_driver+0x30/0x44 bus_remove_device+0x244/0x490 device_del+0x350/0x900 device_unregister+0x28/0xd0 i2c_unregister_device+0x174/0x1d0 v4l2_device_unregister+0x224/0x380 em28xx_v4l2_init+0x1d90/0x3770 The buggy address belongs to the object at ffff8000d7ca2000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 776 bytes inside of 2048-byte region [ffff8000d7ca2000, ffff8000d7ca2800) The buggy address belongs to the page: page:ffff7fe00035f280 count:1 mapcount:0 mapping:ffff8000c001f000 index:0x0 flags: 0x7ff800000000100(slab) raw: 07ff800000000100 ffff7fe00049d880 0000000300000003 ffff8000c001f000 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8000d7ca2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8000d7ca2280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8000d7ca2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8000d7ca2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8000d7ca2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== [2] Actually, it is allocated for struct tuner, and dvb_frontend is inside.

A flaw was found in the crypto subsystem of the Linux kernel before version kernel-4.15-rc4. The "null skcipher" was being dropped when each af_alg_ctx was freed instead of when the aead_tfm was freed. This can cause the null skcipher to be freed while it is still in use leading to a local user being able to crash the system or possibly escalate privileges.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. The nft_setelem_catchall_deactivate() function checks whether the catch-all set element is active in the current generation instead of the next generation before freeing it, but only flags it inactive in the next generation, making it possible to free the element multiple times, leading to a double free vulnerability. We recommend upgrading past commit b1db244ffd041a49ecc9618e8feb6b5c1afcdaa7.

A memory leak flaw was found in the Linux kernel’s io_uring functionality in how a user registers a buffer ring with IORING_REGISTER_PBUF_RING, mmap() it, and then frees it. This flaw allows a local user to crash or potentially escalate their privileges on the system.

A use-after-free flaw was found in the netfilter subsystem of the Linux kernel. If the catchall element is garbage-collected when the pipapo set is removed, the element can be deactivated twice. This can cause a use-after-free issue on an NFT_CHAIN object or NFT_OBJECT object, allowing a local unprivileged user with CAP_NET_ADMIN capability to escalate their privileges on the system.

A use-after-free flaw was found in the Linux Kernel. When a disk is removed, bdi_unregister is called to stop further write-back and waits for associated delayed work to complete. However, wb_inode_writeback_end() may schedule bandwidth estimation work after this has completed, which can result in the timer attempting to access the recently freed bdi_writeback.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. The function nft_pipapo_walk did not skip inactive elements during set walk which could lead double deactivations of PIPAPO (Pile Packet Policies) elements, leading to use-after-free. We recommend upgrading past commit 317eb9685095678f2c9f5a8189de698c5354316a.

In the Linux kernel, the following vulnerability has been resolved: af_unix: Don't return OOB skb in manage_oob(). syzbot reported use-after-free in unix_stream_recv_urg(). [0] The scenario is 1. send(MSG_OOB) 2. recv(MSG_OOB) -> The consumed OOB remains in recv queue 3. send(MSG_OOB) 4. recv() -> manage_oob() returns the next skb of the consumed OOB -> This is also OOB, but unix_sk(sk)->oob_skb is not cleared 5. recv(MSG_OOB) -> unix_sk(sk)->oob_skb is used but already freed The recent commit 8594d9b85c07 ("af_unix: Don't call skb_get() for OOB skb.") uncovered the issue. If the OOB skb is consumed and the next skb is peeked in manage_oob(), we still need to check if the skb is OOB. Let's do so by falling back to the following checks in manage_oob() and add the test case in selftest. Note that we need to add a similar check for SIOCATMARK. [0]: BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959 Read of size 4 at addr ffff8880326abcc4 by task syz-executor178/5235 CPU: 0 UID: 0 PID: 5235 Comm: syz-executor178 Not tainted 6.11.0-rc5-syzkaller-00742-gfbdaffe41adc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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 unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959 unix_stream_recv_urg+0x1df/0x320 net/unix/af_unix.c:2640 unix_stream_read_generic+0x2456/0x2520 net/unix/af_unix.c:2778 unix_stream_recvmsg+0x22b/0x2c0 net/unix/af_unix.c:2996 sock_recvmsg_nosec net/socket.c:1046 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1068 ____sys_recvmsg+0x1db/0x470 net/socket.c:2816 ___sys_recvmsg net/socket.c:2858 [inline] __sys_recvmsg+0x2f0/0x3e0 net/socket.c:2888 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: 0033:0x7f5360d6b4e9 Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff29b3a458 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 00007fff29b3a638 RCX: 00007f5360d6b4e9 RDX: 0000000000002001 RSI: 0000000020000640 RDI: 0000000000000003 RBP: 00007f5360dde610 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff29b3a628 R14: 0000000000000001 R15: 0000000000000001 </TASK> Allocated by task 5235: 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:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:667 alloc_skb include/linux/skbuff.h:1320 [inline] alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6528 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815 sock_alloc_send_skb include/net/sock.h:1778 [inline] queue_oob+0x108/0x680 net/unix/af_unix.c:2198 unix_stream_sendmsg+0xd24/0xf80 net/unix/af_unix.c:2351 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5235: kasan_save_stack mm/kasan/common.c:47 ---truncated---

A use-after-free vulnerability in the Linux kernel's ipv4: igmp component can be exploited to achieve local privilege escalation. A race condition can be exploited to cause a timer be mistakenly registered on a RCU read locked object which is freed by another thread. We recommend upgrading past commit e2b706c691905fe78468c361aaabc719d0a496f1.

A use-after-free vulnerability in the Linux kernel's fs/smb/client component can be exploited to achieve local privilege escalation. In case of an error in smb3_fs_context_parse_param, ctx->password was freed but the field was not set to NULL which could lead to double free. We recommend upgrading past commit e6e43b8aa7cd3c3af686caf0c2e11819a886d705.

In the Linux kernel, the following vulnerability has been resolved: HID: amd_sfh: free driver_data after destroying hid device HID driver callbacks aren't called anymore once hid_destroy_device() has been called. Hence, hid driver_data should be freed only after the hid_destroy_device() function returned as driver_data is used in several callbacks. I observed a crash with kernel 6.10.0 on my T14s Gen 3, after enabling KASAN to debug memory allocation, I got this output: [ 13.050438] ================================================================== [ 13.054060] BUG: KASAN: slab-use-after-free in amd_sfh_get_report+0x3ec/0x530 [amd_sfh] [ 13.054809] psmouse serio1: trackpoint: Synaptics TrackPoint firmware: 0x02, buttons: 3/3 [ 13.056432] Read of size 8 at addr ffff88813152f408 by task (udev-worker)/479 [ 13.060970] CPU: 5 PID: 479 Comm: (udev-worker) Not tainted 6.10.0-arch1-2 #1 893bb55d7f0073f25c46adbb49eb3785fefd74b0 [ 13.063978] Hardware name: LENOVO 21CQCTO1WW/21CQCTO1WW, BIOS R22ET70W (1.40 ) 03/21/2024 [ 13.067860] Call Trace: [ 13.069383] input: TPPS/2 Synaptics TrackPoint as /devices/platform/i8042/serio1/input/input8 [ 13.071486] <TASK> [ 13.071492] dump_stack_lvl+0x5d/0x80 [ 13.074870] snd_hda_intel 0000:33:00.6: enabling device (0000 -> 0002) [ 13.078296] ? amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.082199] print_report+0x174/0x505 [ 13.085776] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 13.089367] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.093255] ? amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.097464] kasan_report+0xc8/0x150 [ 13.101461] ? amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.105802] amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.110303] amdtp_hid_request+0xb8/0x110 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.114879] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.119450] sensor_hub_get_feature+0x1d3/0x540 [hid_sensor_hub 3f13be3016ff415bea03008d45d99da837ee3082] [ 13.124097] hid_sensor_parse_common_attributes+0x4d0/0xad0 [hid_sensor_iio_common c3a5cbe93969c28b122609768bbe23efe52eb8f5] [ 13.127404] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.131925] ? __pfx_hid_sensor_parse_common_attributes+0x10/0x10 [hid_sensor_iio_common c3a5cbe93969c28b122609768bbe23efe52eb8f5] [ 13.136455] ? _raw_spin_lock_irqsave+0x96/0xf0 [ 13.140197] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 13.143602] ? devm_iio_device_alloc+0x34/0x50 [industrialio 3d261d5e5765625d2b052be40e526d62b1d2123b] [ 13.147234] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.150446] ? __devm_add_action+0x167/0x1d0 [ 13.155061] hid_gyro_3d_probe+0x120/0x7f0 [hid_sensor_gyro_3d 63da36a143b775846ab2dbb86c343b401b5e3172] [ 13.158581] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.161814] platform_probe+0xa2/0x150 [ 13.165029] really_probe+0x1e3/0x8a0 [ 13.168243] __driver_probe_device+0x18c/0x370 [ 13.171500] driver_probe_device+0x4a/0x120 [ 13.175000] __driver_attach+0x190/0x4a0 [ 13.178521] ? __pfx___driver_attach+0x10/0x10 [ 13.181771] bus_for_each_dev+0x106/0x180 [ 13.185033] ? __pfx__raw_spin_lock+0x10/0x10 [ 13.188229] ? __pfx_bus_for_each_dev+0x10/0x10 [ 13.191446] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.194382] bus_add_driver+0x29e/0x4d0 [ 13.197328] driver_register+0x1a5/0x360 [ 13.200283] ? __pfx_hid_gyro_3d_platform_driver_init+0x10/0x10 [hid_sensor_gyro_3d 63da36a143b775846ab2dbb86c343b401b5e3172] [ 13.203362] do_one_initcall+0xa7/0x380 [ 13.206432] ? __pfx_do_one_initcall+0x10/0x10 [ 13.210175] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.213211] ? kasan_unpoison+0x44/0x70 [ 13.216688] do_init_module+0x238/0x750 [ 13.2196 ---truncated---

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. The function nft_trans_gc_catchall did not remove the catchall set element from the catchall_list when the argument sync is true, making it possible to free a catchall set element many times. We recommend upgrading past commit 93995bf4af2c5a99e2a87f0cd5ce547d31eb7630.

In the Linux kernel, the following vulnerability has been resolved: vc_screen: move load of struct vc_data pointer in vcs_read() to avoid UAF After a call to console_unlock() in vcs_read() the vc_data struct can be freed by vc_deallocate(). Because of that, the struct vc_data pointer load must be done at the top of while loop in vcs_read() to avoid a UAF when vcs_size() is called. Syzkaller reported a UAF in vcs_size(). BUG: KASAN: use-after-free in vcs_size (drivers/tty/vt/vc_screen.c:215) Read of size 4 at addr ffff8881137479a8 by task 4a005ed81e27e65/1537 CPU: 0 PID: 1537 Comm: 4a005ed81e27e65 Not tainted 6.2.0-rc5 #1 Hardware name: Red Hat KVM, BIOS 1.15.0-2.module Call Trace: <TASK> __asan_report_load4_noabort (mm/kasan/report_generic.c:350) vcs_size (drivers/tty/vt/vc_screen.c:215) vcs_read (drivers/tty/vt/vc_screen.c:415) vfs_read (fs/read_write.c:468 fs/read_write.c:450) ... </TASK> Allocated by task 1191: ... kmalloc_trace (mm/slab_common.c:1069) vc_allocate (./include/linux/slab.h:580 ./include/linux/slab.h:720 drivers/tty/vt/vt.c:1128 drivers/tty/vt/vt.c:1108) con_install (drivers/tty/vt/vt.c:3383) tty_init_dev (drivers/tty/tty_io.c:1301 drivers/tty/tty_io.c:1413 drivers/tty/tty_io.c:1390) tty_open (drivers/tty/tty_io.c:2080 drivers/tty/tty_io.c:2126) chrdev_open (fs/char_dev.c:415) do_dentry_open (fs/open.c:883) vfs_open (fs/open.c:1014) ... Freed by task 1548: ... kfree (mm/slab_common.c:1021) vc_port_destruct (drivers/tty/vt/vt.c:1094) tty_port_destructor (drivers/tty/tty_port.c:296) tty_port_put (drivers/tty/tty_port.c:312) vt_disallocate_all (drivers/tty/vt/vt_ioctl.c:662 (discriminator 2)) vt_ioctl (drivers/tty/vt/vt_ioctl.c:903) tty_ioctl (drivers/tty/tty_io.c:2776) ... The buggy address belongs to the object at ffff888113747800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 424 bytes inside of 1024-byte region [ffff888113747800, ffff888113747c00) The buggy address belongs to the physical page: page:00000000b3fe6c7c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x113740 head:00000000b3fe6c7c order:3 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 anon flags: 0x17ffffc0010200(slab|head|node=0|zone=2|lastcpupid=0x1fffff) raw: 0017ffffc0010200 ffff888100042dc0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888113747880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888113747900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888113747980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888113747a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888113747a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Disabling lock debugging due to kernel taint

In the Linux kernel, the following vulnerability has been resolved: net: fix UaF in netns ops registration error path If net_assign_generic() fails, the current error path in ops_init() tries to clear the gen pointer slot. Anyway, in such error path, the gen pointer itself has not been modified yet, and the existing and accessed one is smaller than the accessed index, causing an out-of-bounds error: BUG: KASAN: slab-out-of-bounds in ops_init+0x2de/0x320 Write of size 8 at addr ffff888109124978 by task modprobe/1018 CPU: 2 PID: 1018 Comm: modprobe Not tainted 6.2.0-rc2.mptcp_ae5ac65fbed5+ #1641 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6a/0x9f print_address_description.constprop.0+0x86/0x2b5 print_report+0x11b/0x1fb kasan_report+0x87/0xc0 ops_init+0x2de/0x320 register_pernet_operations+0x2e4/0x750 register_pernet_subsys+0x24/0x40 tcf_register_action+0x9f/0x560 do_one_initcall+0xf9/0x570 do_init_module+0x190/0x650 load_module+0x1fa5/0x23c0 __do_sys_finit_module+0x10d/0x1b0 do_syscall_64+0x58/0x80 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f42518f778d Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 8b 0d cb 56 2c 00 f7 d8 64 89 01 48 RSP: 002b:00007fff96869688 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 00005568ef7f7c90 RCX: 00007f42518f778d RDX: 0000000000000000 RSI: 00005568ef41d796 RDI: 0000000000000003 RBP: 00005568ef41d796 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 00005568ef7f7d30 R14: 0000000000040000 R15: 0000000000000000 </TASK> This change addresses the issue by skipping the gen pointer de-reference in the mentioned error-path. Found by code inspection and verified with explicit error injection on a kasan-enabled kernel.

In the Linux kernel, the following vulnerability has been resolved: Input: synaptics-rmi4 - fix use after free in rmi_unregister_function() The put_device() calls rmi_release_function() which frees "fn" so the dereference on the next line "fn->num_of_irqs" is a use after free. Move the put_device() to the end to fix this.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Always stop health timer during driver removal Currently, if teardown_hca fails to execute during driver removal, mlx5 does not stop the health timer. Afterwards, mlx5 continue with driver teardown. This may lead to a UAF bug, which results in page fault Oops[1], since the health timer invokes after resources were freed. Hence, stop the health monitor even if teardown_hca fails. [1] mlx5_core 0000:18:00.0: E-Switch: Unload vfs: mode(LEGACY), nvfs(0), necvfs(0), active vports(0) mlx5_core 0000:18:00.0: E-Switch: Disable: mode(LEGACY), nvfs(0), necvfs(0), active vports(0) mlx5_core 0000:18:00.0: E-Switch: Disable: mode(LEGACY), nvfs(0), necvfs(0), active vports(0) mlx5_core 0000:18:00.0: E-Switch: cleanup mlx5_core 0000:18:00.0: wait_func:1155:(pid 1967079): TEARDOWN_HCA(0x103) timeout. Will cause a leak of a command resource mlx5_core 0000:18:00.0: mlx5_function_close:1288:(pid 1967079): tear_down_hca failed, skip cleanup BUG: unable to handle page fault for address: ffffa26487064230 PGD 100c00067 P4D 100c00067 PUD 100e5a067 PMD 105ed7067 PTE 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 0 Comm: swapper/0 Tainted: G OE ------- --- 6.7.0-68.fc38.x86_64 #1 Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0013.121520200651 12/15/2020 RIP: 0010:ioread32be+0x34/0x60 RSP: 0018:ffffa26480003e58 EFLAGS: 00010292 RAX: ffffa26487064200 RBX: ffff9042d08161a0 RCX: ffff904c108222c0 RDX: 000000010bbf1b80 RSI: ffffffffc055ddb0 RDI: ffffa26487064230 RBP: ffff9042d08161a0 R08: 0000000000000022 R09: ffff904c108222e8 R10: 0000000000000004 R11: 0000000000000441 R12: ffffffffc055ddb0 R13: ffffa26487064200 R14: ffffa26480003f00 R15: ffff904c108222c0 FS: 0000000000000000(0000) GS:ffff904c10800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffa26487064230 CR3: 00000002c4420006 CR4: 00000000007706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <IRQ> ? __die+0x23/0x70 ? page_fault_oops+0x171/0x4e0 ? exc_page_fault+0x175/0x180 ? asm_exc_page_fault+0x26/0x30 ? __pfx_poll_health+0x10/0x10 [mlx5_core] ? __pfx_poll_health+0x10/0x10 [mlx5_core] ? ioread32be+0x34/0x60 mlx5_health_check_fatal_sensors+0x20/0x100 [mlx5_core] ? __pfx_poll_health+0x10/0x10 [mlx5_core] poll_health+0x42/0x230 [mlx5_core] ? __next_timer_interrupt+0xbc/0x110 ? __pfx_poll_health+0x10/0x10 [mlx5_core] call_timer_fn+0x21/0x130 ? __pfx_poll_health+0x10/0x10 [mlx5_core] __run_timers+0x222/0x2c0 run_timer_softirq+0x1d/0x40 __do_softirq+0xc9/0x2c8 __irq_exit_rcu+0xa6/0xc0 sysvec_apic_timer_interrupt+0x72/0x90 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:cpuidle_enter_state+0xcc/0x440 ? cpuidle_enter_state+0xbd/0x440 cpuidle_enter+0x2d/0x40 do_idle+0x20d/0x270 cpu_startup_entry+0x2a/0x30 rest_init+0xd0/0xd0 arch_call_rest_init+0xe/0x30 start_kernel+0x709/0xa90 x86_64_start_reservations+0x18/0x30 x86_64_start_kernel+0x96/0xa0 secondary_startup_64_no_verify+0x18f/0x19b ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: scsi: iscsi_tcp: Fix UAF during login when accessing the shost ipaddress If during iscsi_sw_tcp_session_create() iscsi_tcp_r2tpool_alloc() fails, userspace could be accessing the host's ipaddress attr. If we then free the session via iscsi_session_teardown() while userspace is still accessing the session we will hit a use after free bug. Set the tcp_sw_host->session after we have completed session creation and can no longer fail.

In the Linux kernel, the following vulnerability has been resolved: f2fs: compress: fix to avoid use-after-free on dic Call trace: __memcpy+0x128/0x250 f2fs_read_multi_pages+0x940/0xf7c f2fs_mpage_readpages+0x5a8/0x624 f2fs_readahead+0x5c/0x110 page_cache_ra_unbounded+0x1b8/0x590 do_sync_mmap_readahead+0x1dc/0x2e4 filemap_fault+0x254/0xa8c f2fs_filemap_fault+0x2c/0x104 __do_fault+0x7c/0x238 do_handle_mm_fault+0x11bc/0x2d14 do_mem_abort+0x3a8/0x1004 el0_da+0x3c/0xa0 el0t_64_sync_handler+0xc4/0xec el0t_64_sync+0x1b4/0x1b8 In f2fs_read_multi_pages(), once f2fs_decompress_cluster() was called if we hit cached page in compress_inode's cache, dic may be released, it needs break the loop rather than continuing it, in order to avoid accessing invalid dic pointer.

In the Linux kernel, the following vulnerability has been resolved: gfs2: Fix slab-use-after-free in gfs2_qd_dealloc In gfs2_put_super(), whether withdrawn or not, the quota should be cleaned up by gfs2_quota_cleanup(). Otherwise, struct gfs2_sbd will be freed before gfs2_qd_dealloc (rcu callback) has run for all gfs2_quota_data objects, resulting in use-after-free. Also, gfs2_destroy_threads() and gfs2_quota_cleanup() is already called by gfs2_make_fs_ro(), so in gfs2_put_super(), after calling gfs2_make_fs_ro(), there is no need to call them again.

In the Linux kernel, the following vulnerability has been resolved: binder: fix use-after-free in shinker's callback The mmap read lock is used during the shrinker's callback, which means that using alloc->vma pointer isn't safe as it can race with munmap(). As of commit dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap") the mmap lock is downgraded after the vma has been isolated. I was able to reproduce this issue by manually adding some delays and triggering page reclaiming through the shrinker's debug sysfs. The following KASAN report confirms the UAF: ================================================================== BUG: KASAN: slab-use-after-free in zap_page_range_single+0x470/0x4b8 Read of size 8 at addr ffff356ed50e50f0 by task bash/478 CPU: 1 PID: 478 Comm: bash Not tainted 6.6.0-rc5-00055-g1c8b86a3799f-dirty #70 Hardware name: linux,dummy-virt (DT) Call trace: zap_page_range_single+0x470/0x4b8 binder_alloc_free_page+0x608/0xadc __list_lru_walk_one+0x130/0x3b0 list_lru_walk_node+0xc4/0x22c binder_shrink_scan+0x108/0x1dc shrinker_debugfs_scan_write+0x2b4/0x500 full_proxy_write+0xd4/0x140 vfs_write+0x1ac/0x758 ksys_write+0xf0/0x1dc __arm64_sys_write+0x6c/0x9c Allocated by task 492: kmem_cache_alloc+0x130/0x368 vm_area_alloc+0x2c/0x190 mmap_region+0x258/0x18bc do_mmap+0x694/0xa60 vm_mmap_pgoff+0x170/0x29c ksys_mmap_pgoff+0x290/0x3a0 __arm64_sys_mmap+0xcc/0x144 Freed by task 491: kmem_cache_free+0x17c/0x3c8 vm_area_free_rcu_cb+0x74/0x98 rcu_core+0xa38/0x26d4 rcu_core_si+0x10/0x1c __do_softirq+0x2fc/0xd24 Last potentially related work creation: __call_rcu_common.constprop.0+0x6c/0xba0 call_rcu+0x10/0x1c vm_area_free+0x18/0x24 remove_vma+0xe4/0x118 do_vmi_align_munmap.isra.0+0x718/0xb5c do_vmi_munmap+0xdc/0x1fc __vm_munmap+0x10c/0x278 __arm64_sys_munmap+0x58/0x7c Fix this issue by performing instead a vma_lookup() which will fail to find the vma that was isolated before the mmap lock downgrade. Note that this option has better performance than upgrading to a mmap write lock which would increase contention. Plus, mmap_write_trylock() has been recently removed anyway.

In the Linux kernel, the following vulnerability has been resolved: IORING_OP_READ did not correctly consume the provided buffer list when read i/o returned < 0 (except for -EAGAIN and -EIOCBQUEUED return). This can lead to a potential use-after-free when the completion via io_rw_done runs at separate context.

In the Linux kernel, the following vulnerability has been resolved: media: pvrusb2: fix use after free on context disconnection Upon module load, a kthread is created targeting the pvr2_context_thread_func function, which may call pvr2_context_destroy and thus call kfree() on the context object. However, that might happen before the usb hub_event handler is able to notify the driver. This patch adds a sanity check before the invalid read reported by syzbot, within the context disconnection call stack.

In the Linux kernel, the following vulnerability has been resolved: ieee802154: ca8210: Fix a potential UAF in ca8210_probe If of_clk_add_provider() fails in ca8210_register_ext_clock(), it calls clk_unregister() to release priv->clk and returns an error. However, the caller ca8210_probe() then calls ca8210_remove(), where priv->clk is freed again in ca8210_unregister_ext_clock(). In this case, a use-after-free may happen in the second time we call clk_unregister(). Fix this by removing the first clk_unregister(). Also, priv->clk could be an error code on failure of clk_register_fixed_rate(). Use IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().

In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: fix htt mlo-offset event locking The ath12k active pdevs are protected by RCU but the htt mlo-offset event handling code calling ath12k_mac_get_ar_by_pdev_id() was not marked as a read-side critical section. Mark the code in question as an RCU read-side critical section to avoid any potential use-after-free issues. Compile tested only.

In the Linux kernel, the following vulnerability has been resolved: nbd: fix uaf in nbd_open Commit 4af5f2e03013 ("nbd: use blk_mq_alloc_disk and blk_cleanup_disk") cleans up disk by blk_cleanup_disk() and it won't set disk->private_data as NULL as before. UAF may be triggered in nbd_open() if someone tries to open nbd device right after nbd_put() since nbd has been free in nbd_dev_remove(). Fix this by implementing ->free_disk and free private data in it.

In the Linux kernel, the following vulnerability has been resolved: hsr: Prevent use after free in prp_create_tagged_frame() The prp_fill_rct() function can fail. In that situation, it frees the skb and returns NULL. Meanwhile on the success path, it returns the original skb. So it's straight forward to fix bug by using the returned value.

In the Linux kernel, the following vulnerability has been resolved: class: fix use-after-free in class_register() The lock_class_key is still registered and can be found in lock_keys_hash hlist after subsys_private is freed in error handler path.A task who iterate over the lock_keys_hash later may cause use-after-free.So fix that up and unregister the lock_class_key before kfree(cp). On our platform, a driver fails to kset_register because of creating duplicate filename '/class/xxx'.With Kasan enabled, it prints a invalid-access bug report. KASAN bug report: BUG: KASAN: invalid-access in lockdep_register_key+0x19c/0x1bc Write of size 8 at addr 15ffff808b8c0368 by task modprobe/252 Pointer tag: [15], memory tag: [fe] CPU: 7 PID: 252 Comm: modprobe Tainted: G W 6.6.0-mainline-maybe-dirty #1 Call trace: dump_backtrace+0x1b0/0x1e4 show_stack+0x2c/0x40 dump_stack_lvl+0xac/0xe0 print_report+0x18c/0x4d8 kasan_report+0xe8/0x148 __hwasan_store8_noabort+0x88/0x98 lockdep_register_key+0x19c/0x1bc class_register+0x94/0x1ec init_module+0xbc/0xf48 [rfkill] do_one_initcall+0x17c/0x72c do_init_module+0x19c/0x3f8 ... Memory state around the buggy address: ffffff808b8c0100: 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a 8a ffffff808b8c0200: 8a 8a 8a 8a 8a 8a 8a 8a fe fe fe fe fe fe fe fe >ffffff808b8c0300: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe ^ ffffff808b8c0400: 03 03 03 03 03 03 03 03 03 03 03 03 03 03 03 03 As CONFIG_KASAN_GENERIC is not set, Kasan reports invalid-access not use-after-free here.In this case, modprobe is manipulating the corrupted lock_keys_hash hlish where lock_class_key is already freed before. It's worth noting that this only can happen if lockdep is enabled, which is not true for normal system.

In the Linux kernel, the following vulnerability has been resolved: netns: Make get_net_ns() handle zero refcount net Syzkaller hit a warning: refcount_t: addition on 0; use-after-free. WARNING: CPU: 3 PID: 7890 at lib/refcount.c:25 refcount_warn_saturate+0xdf/0x1d0 Modules linked in: CPU: 3 PID: 7890 Comm: tun Not tainted 6.10.0-rc3-00100-gcaa4f9578aba-dirty #310 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:refcount_warn_saturate+0xdf/0x1d0 Code: 41 49 04 31 ff 89 de e8 9f 1e cd fe 84 db 75 9c e8 76 26 cd fe c6 05 b6 41 49 04 01 90 48 c7 c7 b8 8e 25 86 e8 d2 05 b5 fe 90 <0f> 0b 90 90 e9 79 ff ff ff e8 53 26 cd fe 0f b6 1 RSP: 0018:ffff8881067b7da0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c72ac RDX: ffff8881026a2140 RSI: ffffffff811c72b5 RDI: 0000000000000001 RBP: ffff8881067b7db0 R08: 0000000000000000 R09: 205b5d3730353139 R10: 0000000000000000 R11: 205d303938375420 R12: ffff8881086500c4 R13: ffff8881086500c4 R14: ffff8881086500b0 R15: ffff888108650040 FS: 00007f5b2961a4c0(0000) GS:ffff88823bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d7ed36fd18 CR3: 00000001482f6000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? show_regs+0xa3/0xc0 ? __warn+0xa5/0x1c0 ? refcount_warn_saturate+0xdf/0x1d0 ? report_bug+0x1fc/0x2d0 ? refcount_warn_saturate+0xdf/0x1d0 ? handle_bug+0xa1/0x110 ? exc_invalid_op+0x3c/0xb0 ? asm_exc_invalid_op+0x1f/0x30 ? __warn_printk+0xcc/0x140 ? __warn_printk+0xd5/0x140 ? refcount_warn_saturate+0xdf/0x1d0 get_net_ns+0xa4/0xc0 ? __pfx_get_net_ns+0x10/0x10 open_related_ns+0x5a/0x130 __tun_chr_ioctl+0x1616/0x2370 ? __sanitizer_cov_trace_switch+0x58/0xa0 ? __sanitizer_cov_trace_const_cmp2+0x1c/0x30 ? __pfx_tun_chr_ioctl+0x10/0x10 tun_chr_ioctl+0x2f/0x40 __x64_sys_ioctl+0x11b/0x160 x64_sys_call+0x1211/0x20d0 do_syscall_64+0x9e/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5b28f165d7 Code: b3 66 90 48 8b 05 b1 48 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 8 RSP: 002b:00007ffc2b59c5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5b28f165d7 RDX: 0000000000000000 RSI: 00000000000054e3 RDI: 0000000000000003 RBP: 00007ffc2b59c650 R08: 00007f5b291ed8c0 R09: 00007f5b2961a4c0 R10: 0000000029690010 R11: 0000000000000246 R12: 0000000000400730 R13: 00007ffc2b59cf40 R14: 0000000000000000 R15: 0000000000000000 </TASK> Kernel panic - not syncing: kernel: panic_on_warn set ... This is trigger as below: ns0 ns1 tun_set_iff() //dev is tun0 tun->dev = dev //ip link set tun0 netns ns1 put_net() //ref is 0 __tun_chr_ioctl() //TUNGETDEVNETNS net = dev_net(tun->dev); open_related_ns(&net->ns, get_net_ns); //ns1 get_net_ns() get_net() //addition on 0 Use maybe_get_net() in get_net_ns in case net's ref is zero to fix this

In the Linux kernel, the following vulnerability has been resolved: media: mtk-jpeg: Fix use after free bug due to error path handling in mtk_jpeg_dec_device_run In mtk_jpeg_probe, &jpeg->job_timeout_work is bound with mtk_jpeg_job_timeout_work. In mtk_jpeg_dec_device_run, if error happens in mtk_jpeg_set_dec_dst, it will finally start the worker while mark the job as finished by invoking v4l2_m2m_job_finish. There are two methods to trigger the bug. If we remove the module, it which will call mtk_jpeg_remove to make cleanup. The possible sequence is as follows, which will cause a use-after-free bug. CPU0 CPU1 mtk_jpeg_dec_... | start worker | |mtk_jpeg_job_timeout_work mtk_jpeg_remove | v4l2_m2m_release | kfree(m2m_dev); | | | v4l2_m2m_get_curr_priv | m2m_dev->curr_ctx //use If we close the file descriptor, which will call mtk_jpeg_release, it will have a similar sequence. Fix this bug by starting timeout worker only if started jpegdec worker successfully. Then v4l2_m2m_job_finish will only be called in either mtk_jpeg_job_timeout_work or mtk_jpeg_dec_device_run.

In the Linux kernel, the following vulnerability has been resolved: Input: powermate - fix use-after-free in powermate_config_complete syzbot has found a use-after-free bug [1] in the powermate driver. This happens when the device is disconnected, which leads to a memory free from the powermate_device struct. When an asynchronous control message completes after the kfree and its callback is invoked, the lock does not exist anymore and hence the bug. Use usb_kill_urb() on pm->config to cancel any in-progress requests upon device disconnection. [1] https://syzkaller.appspot.com/bug?extid=0434ac83f907a1dbdd1e

In the Linux kernel, the following vulnerability has been resolved: RDMA/srp: Do not call scsi_done() from srp_abort() After scmd_eh_abort_handler() has called the SCSI LLD eh_abort_handler callback, it performs one of the following actions: * Call scsi_queue_insert(). * Call scsi_finish_command(). * Call scsi_eh_scmd_add(). Hence, SCSI abort handlers must not call scsi_done(). Otherwise all the above actions would trigger a use-after-free. Hence remove the scsi_done() call from srp_abort(). Keep the srp_free_req() call before returning SUCCESS because we may not see the command again if SUCCESS is returned.

In the Linux kernel, the following vulnerability has been resolved: drm/i915: Avoid potential vm use-after-free Adding the vm to the vm_xa table makes it visible to userspace, which could try to race with us to close the vm. So we need to take our extra reference before putting it in the table. (cherry picked from commit 99343c46d4e2b34c285d3d5f68ff04274c2f9fb4)

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. Addition and removal of rules from chain bindings within the same transaction causes leads to use-after-free. We recommend upgrading past commit f15f29fd4779be8a418b66e9d52979bb6d6c2325.

In the Linux kernel, the following vulnerability has been resolved: sched/psi: Fix use-after-free in ep_remove_wait_queue() If a non-root cgroup gets removed when there is a thread that registered trigger and is polling on a pressure file within the cgroup, the polling waitqueue gets freed in the following path: do_rmdir cgroup_rmdir kernfs_drain_open_files cgroup_file_release cgroup_pressure_release psi_trigger_destroy However, the polling thread still has a reference to the pressure file and will access the freed waitqueue when the file is closed or upon exit: fput ep_eventpoll_release ep_free ep_remove_wait_queue remove_wait_queue This results in use-after-free as pasted below. The fundamental problem here is that cgroup_file_release() (and consequently waitqueue's lifetime) is not tied to the file's real lifetime. Using wake_up_pollfree() here might be less than ideal, but it is in line with the comment at commit 42288cb44c4b ("wait: add wake_up_pollfree()") since the waitqueue's lifetime is not tied to file's one and can be considered as another special case. While this would be fixable by somehow making cgroup_file_release() be tied to the fput(), it would require sizable refactoring at cgroups or higher layer which might be more justifiable if we identify more cases like this. BUG: KASAN: use-after-free in _raw_spin_lock_irqsave+0x60/0xc0 Write of size 4 at addr ffff88810e625328 by task a.out/4404 CPU: 19 PID: 4404 Comm: a.out Not tainted 6.2.0-rc6 #38 Hardware name: Amazon EC2 c5a.8xlarge/, BIOS 1.0 10/16/2017 Call Trace: <TASK> dump_stack_lvl+0x73/0xa0 print_report+0x16c/0x4e0 kasan_report+0xc3/0xf0 kasan_check_range+0x2d2/0x310 _raw_spin_lock_irqsave+0x60/0xc0 remove_wait_queue+0x1a/0xa0 ep_free+0x12c/0x170 ep_eventpoll_release+0x26/0x30 __fput+0x202/0x400 task_work_run+0x11d/0x170 do_exit+0x495/0x1130 do_group_exit+0x100/0x100 get_signal+0xd67/0xde0 arch_do_signal_or_restart+0x2a/0x2b0 exit_to_user_mode_prepare+0x94/0x100 syscall_exit_to_user_mode+0x20/0x40 do_syscall_64+0x52/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd </TASK> Allocated by task 4404: kasan_set_track+0x3d/0x60 __kasan_kmalloc+0x85/0x90 psi_trigger_create+0x113/0x3e0 pressure_write+0x146/0x2e0 cgroup_file_write+0x11c/0x250 kernfs_fop_write_iter+0x186/0x220 vfs_write+0x3d8/0x5c0 ksys_write+0x90/0x110 do_syscall_64+0x43/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 4407: kasan_set_track+0x3d/0x60 kasan_save_free_info+0x27/0x40 ____kasan_slab_free+0x11d/0x170 slab_free_freelist_hook+0x87/0x150 __kmem_cache_free+0xcb/0x180 psi_trigger_destroy+0x2e8/0x310 cgroup_file_release+0x4f/0xb0 kernfs_drain_open_files+0x165/0x1f0 kernfs_drain+0x162/0x1a0 __kernfs_remove+0x1fb/0x310 kernfs_remove_by_name_ns+0x95/0xe0 cgroup_addrm_files+0x67f/0x700 cgroup_destroy_locked+0x283/0x3c0 cgroup_rmdir+0x29/0x100 kernfs_iop_rmdir+0xd1/0x140 vfs_rmdir+0xfe/0x240 do_rmdir+0x13d/0x280 __x64_sys_rmdir+0x2c/0x30 do_syscall_64+0x43/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for bfqq in bic_set_bfqq() After commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'"), bic->bfqq will be accessed in bic_set_bfqq(), however, in some context bic->bfqq will be freed, and bic_set_bfqq() is called with the freed bic->bfqq. Fix the problem by always freeing bfqq after bic_set_bfqq().

In the Linux kernel, the following vulnerability has been resolved: can: bcm: Fix UAF in bcm_proc_show() BUG: KASAN: slab-use-after-free in bcm_proc_show+0x969/0xa80 Read of size 8 at addr ffff888155846230 by task cat/7862 CPU: 1 PID: 7862 Comm: cat Not tainted 6.5.0-rc1-00153-gc8746099c197 #230 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0xd5/0x150 print_report+0xc1/0x5e0 kasan_report+0xba/0xf0 bcm_proc_show+0x969/0xa80 seq_read_iter+0x4f6/0x1260 seq_read+0x165/0x210 proc_reg_read+0x227/0x300 vfs_read+0x1d5/0x8d0 ksys_read+0x11e/0x240 do_syscall_64+0x35/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd Allocated by task 7846: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_kmalloc+0x9e/0xa0 bcm_sendmsg+0x264b/0x44e0 sock_sendmsg+0xda/0x180 ____sys_sendmsg+0x735/0x920 ___sys_sendmsg+0x11d/0x1b0 __sys_sendmsg+0xfa/0x1d0 do_syscall_64+0x35/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 7846: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x27/0x40 ____kasan_slab_free+0x161/0x1c0 slab_free_freelist_hook+0x119/0x220 __kmem_cache_free+0xb4/0x2e0 rcu_core+0x809/0x1bd0 bcm_op is freed before procfs entry be removed in bcm_release(), this lead to bcm_proc_show() may read the freed bcm_op.

In the Linux kernel, the following vulnerability has been resolved: vhost-vdpa: fix use after free in vhost_vdpa_probe() The put_device() calls vhost_vdpa_release_dev() which calls ida_simple_remove() and frees "v". So this call to ida_simple_remove() is a use after free and a double free.