Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2025-21631— block, bfq: fix waker_bfqq UAF after bfq_split_bfqq()

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于内存释放后重用。

CVSS 7.8 · High EPSS 0.21% · P11

Possible ATT&CK Techniques 1 AI

T1068 · Exploitation for Privilege Escalation

Affected Version Matrix 19

VendorProduct Version RangeStatus
Linux Linux 63a07379fdb6c72450cb05294461c6016b8b7726< f587c1ac68956c4703857d650d9b1cd7bb2ac4d7 affected
de0456460f2abf921e356ed2bd8da87a376680bd< 2550149fcdf2934155ff625d76ad4e3d4b25bbc6 affected
0780451f03bf518bc032a7c584de8f92e2d39d7f< be3eed59ac01f429ac10aaa46e26f653bcf581ab affected
1ba0403ac6447f2d63914fb760c44a3b19c44eaf< bc2aeb35ff167e0c6b0cedf0c96a5c41e6cba1ed affected
1ba0403ac6447f2d63914fb760c44a3b19c44eaf< fcede1f0a043ccefe9bc6ad57f12718e42f63f1d affected
0b8bda0ff17156cd3f60944527c9d8c9f99f1583 affected
cae58d19121a70329cf971359e2518c93fec04fe affected
5.15.168< 5.15.177 affected
… +11 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2025-21631

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
block, bfq: fix waker_bfqq UAF after bfq_split_bfqq()
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix waker_bfqq UAF after bfq_split_bfqq() Our syzkaller report a following UAF for v6.6: BUG: KASAN: slab-use-after-free in bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958 Read of size 8 at addr ffff8881b57147d8 by task fsstress/232726 CPU: 2 PID: 232726 Comm: fsstress Not tainted 6.6.0-g3629d1885222 #39 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106 print_address_description.constprop.0+0x66/0x300 mm/kasan/report.c:364 print_report+0x3e/0x70 mm/kasan/report.c:475 kasan_report+0xb8/0xf0 mm/kasan/report.c:588 hlist_add_head include/linux/list.h:1023 [inline] bfq_init_rq+0x175d/0x17a0 block/bfq-iosched.c:6958 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143 __submit_bio+0xa0/0x6b0 block/blk-core.c:639 __submit_bio_noacct_mq block/blk-core.c:718 [inline] submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847 __ext4_read_bh fs/ext4/super.c:205 [inline] ext4_read_bh+0x15e/0x2e0 fs/ext4/super.c:230 __read_extent_tree_block+0x304/0x6f0 fs/ext4/extents.c:567 ext4_find_extent+0x479/0xd20 fs/ext4/extents.c:947 ext4_ext_map_blocks+0x1a3/0x2680 fs/ext4/extents.c:4182 ext4_map_blocks+0x929/0x15a0 fs/ext4/inode.c:660 ext4_iomap_begin_report+0x298/0x480 fs/ext4/inode.c:3569 iomap_iter+0x3dd/0x1010 fs/iomap/iter.c:91 iomap_fiemap+0x1f4/0x360 fs/iomap/fiemap.c:80 ext4_fiemap+0x181/0x210 fs/ext4/extents.c:5051 ioctl_fiemap.isra.0+0x1b4/0x290 fs/ioctl.c:220 do_vfs_ioctl+0x31c/0x11a0 fs/ioctl.c:811 __do_sys_ioctl fs/ioctl.c:869 [inline] __se_sys_ioctl+0xae/0x190 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x70/0x120 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x78/0xe2 Allocated by task 232719: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:768 [inline] slab_alloc_node mm/slub.c:3492 [inline] kmem_cache_alloc_node+0x1b8/0x6f0 mm/slub.c:3537 bfq_get_queue+0x215/0x1f00 block/bfq-iosched.c:5869 bfq_get_bfqq_handle_split+0x167/0x5f0 block/bfq-iosched.c:6776 bfq_init_rq+0x13a4/0x17a0 block/bfq-iosched.c:6938 bfq_insert_request.isra.0+0xe8/0xa20 block/bfq-iosched.c:6271 bfq_insert_requests+0x27f/0x390 block/bfq-iosched.c:6323 blk_mq_insert_request+0x290/0x8f0 block/blk-mq.c:2660 blk_mq_submit_bio+0x1021/0x15e0 block/blk-mq.c:3143 __submit_bio+0xa0/0x6b0 block/blk-core.c:639 __submit_bio_noacct_mq block/blk-core.c:718 [inline] submit_bio_noacct_nocheck+0x5b7/0x810 block/blk-core.c:747 submit_bio_noacct+0xca0/0x1990 block/blk-core.c:847 __ext4_read_bh fs/ext4/super.c:205 [inline] ext4_read_bh_nowait+0x15a/0x240 fs/ext4/super.c:217 ext4_read_bh_lock+0xac/0xd0 fs/ext4/super.c:242 ext4_bread_batch+0x268/0x500 fs/ext4/inode.c:958 __ext4_find_entry+0x448/0x10f0 fs/ext4/namei.c:1671 ext4_lookup_entry fs/ext4/namei.c:1774 [inline] ext4_lookup.part.0+0x359/0x6f0 fs/ext4/namei.c:1842 ext4_lookup+0x72/0x90 fs/ext4/namei.c:1839 __lookup_slow+0x257/0x480 fs/namei.c:1696 lookup_slow fs/namei.c:1713 [inline] walk_component+0x454/0x5c0 fs/namei.c:2004 link_path_walk.part.0+0x773/0xda0 fs/namei.c:2331 link_path_walk fs/namei.c:3826 [inline] path_openat+0x1b9/0x520 fs/namei.c:3826 do_filp_open+0x1b7/0x400 fs/namei.c:3857 do_sys_openat2+0x5dc/0x6e0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x148/0x200 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_6 ---truncated---
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于内存释放后重用。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 63a07379fdb6c72450cb05294461c6016b8b7726 ~ f587c1ac68956c4703857d650d9b1cd7bb2ac4d7 -
Linux Linux 6.12 -

II. Public POCs for CVE-2025-21631

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2025-21631

请登录查看更多情报信息。

Patches & Fixes for CVE-2025-21631 (5)

Same Patch Batch · Linux · 2025-01-19 · 47 CVEs total

CVE-2024-57929 7.8 HIGH dm array: fix releasing a faulty array block twice in dm_array_cursor_end
CVE-2025-21652 7.8 HIGH ipvlan: Fix use-after-free in ipvlan_get_iflink().
CVE-2024-57918 7.8 HIGH drm/amd/display: fix page fault due to max surface definition mismatch
CVE-2024-57921 7.8 HIGH drm/amdgpu: Add a lock when accessing the buddy trim function
CVE-2024-57926 7.8 HIGH drm/mediatek: Set private->all_drm_private[i]->drm to NULL if mtk_drm_bind returns err
CVE-2025-21646 7.5 HIGH afs: Fix the maximum cell name length
CVE-2025-21647 7.3 HIGH sched: sch_cake: add bounds checks to host bulk flow fairness counts
CVE-2025-21640 7.1 HIGH sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy
CVE-2025-21650 7.1 HIGH net: hns3: fixed hclge_fetch_pf_reg accesses bar space out of bounds issue
CVE-2025-21638 7.1 HIGH sctp: sysctl: auth_enable: avoid using current->nsproxy
CVE-2025-21637 7.1 HIGH sctp: sysctl: udp_port: avoid using current->nsproxy
CVE-2024-57923 btrfs: zlib: fix avail_in bytes for s390 zlib HW compression path
CVE-2024-57927 nfs: Fix oops in nfs_netfs_init_request() when copying to cache
CVE-2024-57914 usb: typec: tcpci: fix NULL pointer issue on shared irq case
CVE-2024-57913 usb: gadget: f_fs: Remove WARN_ON in functionfs_bind
CVE-2024-57912 iio: pressure: zpa2326: fix information leak in triggered buffer
CVE-2024-57911 iio: dummy: iio_simply_dummy_buffer: fix information leak in triggered buffer
CVE-2024-57910 iio: light: vcnl4035: fix information leak in triggered buffer
CVE-2024-57908 iio: imu: kmx61: fix information leak in triggered buffer
CVE-2024-57919 drm/amd/display: fix divide error in DM plane scale calcs

Showing top 20 of 47 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2025-21631

No comments yet

Leave a comment