{"id":"DEBIAN-CVE-2021-47598","details":"In the Linux kernel, the following vulnerability has been resolved:  sch_cake: do not call cake_destroy() from cake_init()  qdiscs are not supposed to call their own destroy() method from init(), because core stack already does that.  syzbot was able to trigger use after free:  DEBUG_LOCKS_WARN_ON(lock-\u003emagic != lock) WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock_common kernel/locking/mutex.c:586 [inline] WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Modules linked in: CPU: 0 PID: 21902 Comm: syz-executor189 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:586 [inline] RIP: 0010:__mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740 Code: 08 84 d2 0f 85 19 08 00 00 8b 05 97 38 4b 04 85 c0 0f 85 27 f7 ff ff 48 c7 c6 20 00 ac 89 48 c7 c7 a0 fe ab 89 e8 bf 76 ba ff \u003c0f\u003e 0b e9 0d f7 ff ff 48 8b 44 24 40 48 8d b8 c8 08 00 00 48 89 f8 RSP: 0018:ffffc9000627f290 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802315d700 RSI: ffffffff815f1db8 RDI: fffff52000c4fe44 RBP: ffff88818f28e000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ebb5e R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffc9000627f458 R15: 0000000093c30000 FS:  0000555556abc400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda689c3303 CR3: 000000001cfbb000 CR4: 0000000000350ef0 Call Trace:  \u003cTASK\u003e  tcf_chain0_head_change_cb_del+0x2e/0x3d0 net/sched/cls_api.c:810  tcf_block_put_ext net/sched/cls_api.c:1381 [inline]  tcf_block_put_ext net/sched/cls_api.c:1376 [inline]  tcf_block_put+0xbc/0x130 net/sched/cls_api.c:1394  cake_destroy+0x3f/0x80 net/sched/sch_cake.c:2695  qdisc_create.constprop.0+0x9da/0x10f0 net/sched/sch_api.c:1293  tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660  rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571  netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496  netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]  netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345  netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921  sock_sendmsg_nosec net/socket.c:704 [inline]  sock_sendmsg+0xcf/0x120 net/socket.c:724  ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409  ___sys_sendmsg+0xf3/0x170 net/socket.c:2463  __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492  do_syscall_x64 arch/x86/entry/common.c:50 [inline]  do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80  entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1bb06badb9 Code: Unable to access opcode bytes at RIP 0x7f1bb06bad8f. RSP: 002b:00007fff3012a658 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1bb06badb9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000003 R10: 0000000000000003 R11: 0000000000000246 R12: 00007fff3012a688 R13: 00007fff3012a6a0 R14: 00007fff3012a6e0 R15: 00000000000013c2  \u003c/TASK\u003e","modified":"2026-09-15T09:02:36.046855638Z","published":"2024-06-19T15:15:54.383Z","upstream":["CVE-2021-47598"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-47598"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.15-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47598.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.15-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47598.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.15-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47598.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}