Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_taprio: properly cancel timer from taprio_destroy() There is a comment in qdisc_create() about us not calling ops->reset() in some cases. err_out4: /* * Any broken qdiscs that would require a ops->reset() here? * The qdisc was never in action so it shouldn't be necessary. */ As taprio sets a timer before actually receiving a packet, we need to cancel it from ops->destroy, just in case ops->reset has not been called. syzbot reported: ODEBUG: free active (active state 0) object type: hrtimer hint: advance_sched+0x0/0x9a0 arch/x86/include/asm/atomic64_64.h:22 WARNING: CPU: 0 PID: 8441 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Modules linked in: CPU: 0 PID: 8441 Comm: syz-executor813 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd e0 d3 e3 89 4c 89 ee 48 c7 c7 e0 c7 e3 89 e8 5b 86 11 05 <0f> 0b 83 05 85 03 92 09 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffc9000130f330 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: ffff88802baeb880 RSI: ffffffff815d87b5 RDI: fffff52000261e58 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815d25ee R11: 0000000000000000 R12: ffffffff898dd020 R13: ffffffff89e3ce20 R14: ffffffff81653630 R15: dffffc0000000000 FS: 0000000000f0d300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffb64b3e000 CR3: 0000000036557000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:987 [inline] debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1018 slab_free_hook mm/slub.c:1603 [inline] slab_free_freelist_hook+0x171/0x240 mm/slub.c:1653 slab_free mm/slub.c:3213 [inline] kfree+0xe4/0x540 mm/slub.c:4267 qdisc_create+0xbcf/0x1320 net/sched/sch_api.c:1299 tc_modify_qdisc+0x4c8/0x1a60 net/sched/sch_api.c:1663 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2403 ___sys_sendmsg+0xf3/0x170 net/socket.c:2457 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2486 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80

Metrics

 

CVSS Version 4.0 CVSS Version 3.x CVSS Version 2.0

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.

CVSS 4.0 Severity and Vector Strings:

NIST: NVD

N/A

NVD assessment not yet provided.

CVSS 3.x Severity and Vector Strings:

NIST: NVD

Base Score:  N/A

NVD assessment not yet provided.

ADP:  CISA-ADP

Base Score:  5.5 MEDIUM

Vector:  CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS 2.0 Severity and Vector Strings:

NIST: NVD

Base Score: N/A

NVD assessment not yet provided.

CISA-ADP AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

In the Linux kernel, the following vulnerability has been resolved:

net/sched: sch_taprio: properly cancel timer from taprio_destroy()

There is a comment in qdisc_create() about us not calling ops->reset()
in some cases.

err_out4:
	/*
	 * Any broken qdiscs that would require a ops->reset() here?
	 * The qdisc was never in action so it shouldn't be necessary.
	 */

As taprio sets a timer before actually receiving a packet, we need
to cancel it from ops->destroy, just in case ops->reset has not

kernel.org https://git.kernel.org/stable/c/3ec73ffeef54596c32aff0e73fe60971b9c8b866 [No types assigned]

kernel.org https://git.kernel.org/stable/c/7a1c1af341041221b3acb9d7036cc2b43e0efa75 [No types assigned]

kernel.org https://git.kernel.org/stable/c/a56d447f196fa9973c568f54c0d76d5391c3b0c0 [No types assigned]

kernel.org https://git.kernel.org/stable/c/c951c08a5996365aecbc5f1a9bddec3905e1ddfc [No types assigned]