{"id":"DEBIAN-CVE-2025-21969","details":"In the Linux kernel, the following vulnerability has been resolved:  Bluetooth: L2CAP: Fix slab-use-after-free Read in l2cap_send_cmd  After the hci sync command releases l2cap_conn, the hci receive data work queue references the released l2cap_conn when sending to the upper layer. Add hci dev lock to the hci receive data work queue to synchronize the two.  [1] BUG: KASAN: slab-use-after-free in l2cap_send_cmd+0x187/0x8d0 net/bluetooth/l2cap_core.c:954 Read of size 8 at addr ffff8880271a4000 by task kworker/u9:2/5837  CPU: 0 UID: 0 PID: 5837 Comm: kworker/u9:2 Not tainted 6.13.0-rc5-syzkaller-00163-gab75170520d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci1 hci_rx_work Call Trace:  \u003cTASK\u003e  __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  l2cap_build_cmd net/bluetooth/l2cap_core.c:2964 [inline]  l2cap_send_cmd+0x187/0x8d0 net/bluetooth/l2cap_core.c:954  l2cap_sig_send_rej net/bluetooth/l2cap_core.c:5502 [inline]  l2cap_sig_channel net/bluetooth/l2cap_core.c:5538 [inline]  l2cap_recv_frame+0x221f/0x10db0 net/bluetooth/l2cap_core.c:6817  hci_acldata_packet net/bluetooth/hci_core.c:3797 [inline]  hci_rx_work+0x508/0xdb0 net/bluetooth/hci_core.c:4040  process_one_work kernel/workqueue.c:3229 [inline]  process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310  worker_thread+0x870/0xd30 kernel/workqueue.c:3391  kthread+0x2f0/0x390 kernel/kthread.c:389  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244  \u003c/TASK\u003e  Allocated by task 5837:  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:4329  kmalloc_noprof include/linux/slab.h:901 [inline]  kzalloc_noprof include/linux/slab.h:1037 [inline]  l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6860  l2cap_connect_cfm+0x115/0x1090 net/bluetooth/l2cap_core.c:7239  hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]  hci_remote_features_evt+0x68e/0xac0 net/bluetooth/hci_event.c:3726  hci_event_func net/bluetooth/hci_event.c:7473 [inline]  hci_event_packet+0xac2/0x1540 net/bluetooth/hci_event.c:7525  hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4035  process_one_work kernel/workqueue.c:3229 [inline]  process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310  worker_thread+0x870/0xd30 kernel/workqueue.c:3391  kthread+0x2f0/0x390 kernel/kthread.c:389  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244  Freed by task 54:  kasan_save_stack mm/kasan/common.c:47 [inline]  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68  kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582  poison_slab_object mm/kasan/common.c:247 [inline]  __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264  kasan_slab_free include/linux/kasan.h:233 [inline]  slab_free_hook mm/slub.c:2353 [inline]  slab_free mm/slub.c:4613 [inline]  kfree+0x196/0x430 mm/slub.c:4761  l2cap_connect_cfm+0xcc/0x1090 net/bluetooth/l2cap_core.c:7235  hci_connect_cfm include/net/bluetooth/hci_core.h:2057 [inline]  hci_conn_failed+0x287/0x400 net/bluetooth/hci_conn.c:1266  hci_abort_conn_sync+0x56c/0x11f0 net/bluetooth/hci_sync.c:5603  hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332  process_one_work kernel/workqueue.c:3229 [inline]  process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310  worker_thread+0x870/0xd30 kernel/workqueue.c:3391  kthread+0x2f0/0x390 kernel/kthread.c:389  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entr ---truncated---","modified":"2026-08-27T23:05:12.634546104Z","published":"2025-04-01T16:15:28.207Z","upstream":["CVE-2025-21969"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-21969"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.123-1","6.1.124-1","6.1.128-1","6.1.129-1","6.1.133-1","6.1.135-1","6.1.137-1","6.1.139-1","6.1.140-1","6.1.147-1","6.1.148-1","6.1.153-1","6.1.158-1","6.1.159-1","6.1.162-1","6.1.164-1","6.1.170-1","6.1.170-2","6.1.170-3","6.1.172-1","6.1.174-1","6.1.176-1","6.1.177-1","6.1.180-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1","6.10-1~exp1","6.10.1-1~exp1","6.10.11-1","6.10.11-1~bpo12+1","6.10.12-1","6.10.3-1","6.10.4-1","6.10.6-1","6.10.6-1~bpo12+1","6.10.7-1","6.10.9-1","6.11-1~exp1","6.11.10-1","6.11.10-1~bpo12+1","6.11.2-1","6.11.4-1","6.11.5-1","6.11.5-1~bpo12+1","6.11.6-1","6.11.7-1","6.11.9-1","6.11~rc4-1~exp1","6.11~rc5-1~exp1","6.12.10-1","6.12.100-1","6.12.101-1","6.12.105-1","6.12.11-1","6.12.11-1+alpha","6.12.11-1+alpha.1","6.12.12-1","6.12.12-1~bpo12+1","6.12.13-1","6.12.15-1","6.12.16-1","6.12.17-1","6.12.19-1","6.12.20-1","6.12.21-1","6.12.22-1","6.12.22-1~bpo12+1","6.12.25-1","6.12.27-1","6.12.27-1~bpo12+1","6.12.29-1","6.12.3-1","6.12.30-1","6.12.30-1~bpo12+1","6.12.31-1","6.12.32-1","6.12.32-1~bpo12+1","6.12.33-1","6.12.33-1~bpo12+1","6.12.35-1","6.12.35-1~bpo12+1","6.12.37-1","6.12.38-1","6.12.38-1~bpo12+1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.5-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.6-1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.8-1","6.12.85-1","6.12.85-1~bpo12+1","6.12.86-1","6.12.86-1~bpo12+1","6.12.88-1","6.12.88-1~bpo12+1","6.12.9-1","6.12.9-1+alpha","6.12.9-1~bpo12+1","6.12.90-1","6.12.90-1~bpo12+1","6.12.90-2","6.12.90-2~bpo12+1","6.12.94-1","6.12.94-1~bpo12+1","6.12.95-1","6.12.95-1~bpo12+1","6.12.96-1","6.12~rc6-1~exp1","6.13.10-1~exp1","6.13.11-1~exp1","6.13.2-1~exp1","6.13.3-1~exp1","6.13.4-1~exp1","6.13.5-1~exp1","6.13.6-1~exp1","6.13.7-1~exp1","6.13.8-1~exp1","6.13.9-1~exp1","6.13~rc6-1~exp1","6.13~rc7-1~exp1","6.14.3-1~exp1","6.14.5-1~exp1","6.14.6-1~exp1","6.15-1~exp1","6.15.1-1~exp1","6.15.2-1~exp1","6.15.3-1~exp1","6.15.4-1~exp1","6.15.5-1~exp1","6.15.6-1~exp1","6.15~rc7-1~exp1","6.16-1~exp1","6.16.1-1~exp1","6.16.10-1","6.16.11-1","6.16.12-1","6.16.12-1~bpo13+1","6.16.12-2","6.16.3-1","6.16.3-1~bpo13+1","6.16.5-1","6.16.6-1","6.16.7-1","6.16.8-1","6.16.9-1","6.16~rc7-1~exp1","6.17.10-1","6.17.11-1","6.17.12-1","6.17.13-1","6.17.13-1~bpo13+1","6.17.2-1~exp1","6.17.5-1~exp1","6.17.6-1","6.17.7-1","6.17.7-2","6.17.8-1","6.17.8-1~bpo13+1","6.17.9-1","6.18.1-1~exp1","6.18.10-1","6.18.12-1","6.18.12-1~bpo13+1","6.18.13-1","6.18.14-1","6.18.15-1","6.18.15-1~bpo13+1","6.18.2-1~exp1","6.18.3-1","6.18.5-1","6.18.5-1~bpo13+1","6.18.8-1","6.18.9-1","6.18.9-1~bpo13+1","6.18~rc4-1~exp1","6.18~rc4-1~exp2","6.18~rc5-1~exp1","6.18~rc6-1~exp1","6.18~rc7-1~exp1","6.19-1~exp1","6.19.10-1","6.19.10-1~bpo13+1","6.19.11-1","6.19.11-1~bpo13+1","6.19.12-1","6.19.13-1","6.19.13-1~bpo13+1","6.19.14-1","6.19.14-1~bpo13+1","6.19.2-1~exp1","6.19.3-1~exp1","6.19.4-1~exp1","6.19.5-1~exp1","6.19.6-1","6.19.6-2","6.19.6-2~bpo13+1","6.19.8-1","6.19.8-1~bpo13+1","6.19~rc4-1~exp1","6.19~rc5-1~exp1","6.19~rc6-1~exp1","6.19~rc7-1~exp1","6.19~rc8-1~exp1","6.3.1-1~exp1","6.3.11-1","6.3.2-1~exp1","6.3.4-1~exp1","6.3.5-1~exp1","6.3.7-1","6.3.7-1~bpo12+1","6.4.1-1~exp1","6.4.11-1","6.4.13-1","6.4.4-1","6.4.4-1~bpo12+1","6.4.4-2","6.4.4-3","6.4.4-3~bpo12+1","6.4~rc6-1~exp1","6.4~rc7-1~exp1","6.5.1-1~exp1","6.5.10-1","6.5.10-1~bpo12+1","6.5.13-1","6.5.3-1","6.5.3-1~bpo12+1","6.5.6-1","6.5.8-1","6.5~rc4-1~exp1","6.5~rc6-1~exp1","6.5~rc7-1~exp1","6.6.11-1","6.6.13-1","6.6.13-1~bpo12+1","6.6.15-1","6.6.15-2","6.6.3-1~exp1","6.6.4-1~exp1","6.6.7-1~exp1","6.6.8-1","6.6.9-1","6.7-1~exp1","6.7.1-1~exp1","6.7.12-1","6.7.12-1~bpo12+1","6.7.4-1~exp1","6.7.7-1","6.7.9-1","6.7.9-2","6.8.11-1","6.8.12-1","6.8.12-1~bpo12+1","6.8.9-1","6.9.10-1","6.9.10-1~bpo12+1","6.9.11-1","6.9.12-1","6.9.2-1~exp1","6.9.7-1","6.9.7-1~bpo12+1","6.9.8-1","6.9.9-1","7.0-1~exp1","7.0.1-1~exp1","7.0.10-1","7.0.10-1~bpo13+1","7.0.12-1","7.0.12-2","7.0.12-2~bpo13+1","7.0.13-1","7.0.13-1~bpo13+1","7.0.14-1","7.0.3-1","7.0.4-1","7.0.4-1~bpo13+1","7.0.7-1","7.0.7-1~bpo13+1","7.0.9-1","7.0.9-1~bpo13+1","7.1.1-1~exp1","7.1.10-1","7.1.2-1~exp1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