syzbot


BUG: unable to handle kernel NULL pointer dereference in hrtimer_active

Status: fixed on 2024/03/27 19:12
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+039399a9b96297ddedca@syzkaller.appspotmail.com
Fix commit: fe9f801355f0 net: veth: clear GRO when clearing XDP even when down
First crash: 70d, last: 70d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH net 1/2] net: veth: clear GRO when clearing XDP even when down 3 (3) 2024/02/26 11:40
[syzbot] [kernel?] BUG: unable to handle kernel NULL pointer dereference in hrtimer_active 2 (3) 2024/02/21 21:29
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: null-ptr-deref Read in hrtimer_active kernel 7 152d 290d 0/26 closed as invalid on 2024/01/16 13:47
upstream general protection fault in hrtimer_active (3) kernel syz done error 34 809d 1114d 20/26 fixed on 2022/03/08 16:11
upstream general protection fault in hrtimer_active (5) kernel C error 22 432d 436d 22/26 fixed on 2023/06/08 14:41
upstream general protection fault in hrtimer_active (4) kernel 7 639d 748d 0/26 auto-obsoleted due to no activity on 2022/10/20 15:45

Sample crash report:
infiniband syz0: set active
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
Mem abort info:
  ESR = 0x0000000097810006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  Access size = 4 byte(s)
  SSE = 0, SRT = 1
  SF = 0, AR = 0
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000006f316000
[0000000000000010] pgd=080000006f27f003, p4d=080000006f27f003, pud=080000006f31a003, pmd=0000000000000000
Internal error: Oops: 0000000097810006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 3665 Comm: syz-executor.0 Not tainted 6.8.0-rc3-syzkaller-00279-g4a7bbe7519b6 #0
Hardware name: linux,dummy-virt (DT)
pstate: 61400009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : __seqprop_raw_spinlock_sequence include/linux/seqlock.h:226 [inline]
pc : hrtimer_active+0x4/0x60 kernel/time/hrtimer.c:1614
lr : hrtimer_try_to_cancel+0x1c/0xf8 kernel/time/hrtimer.c:1331
sp : ffff800082c63300
x29: ffff800082c63300 x28: 0000000000000000 x27: 0000000000000000
x26: 0000000000000340 x25: 0000000000000000 x24: f3ff00001ab7e9e0
x23: 0000000000000000 x22: 000061100fc019e9 x21: 0000000000000009
x20: 0000000000000000 x19: fbff00001abf9920 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: ffff80008144d28c
x14: ffff80008144d20c x13: ffff80008144d28c x12: ffff80008144d20c
x11: ffff800080011558 x10: ffff800081907d14 x9 : ffff8000819078a4
x8 : ffff800082c63408 x7 : 0000000000000000 x6 : ffff800080026d20
x5 : f2ff000033f2c800 x4 : 000061100fc019e9 x3 : 0000000000000340
x2 : 0000000000000000 x1 : 000000000000000d x0 : fbff00001abf9920
Call trace:
 hrtimer_active+0x4/0x60 kernel/time/hrtimer.c:1613
 hrtimer_cancel+0x1c/0x38 kernel/time/hrtimer.c:1446
 napi_disable+0x5c/0x11c net/core/dev.c:6502
 veth_napi_del_range+0x64/0x1d8 drivers/net/veth.c:1109
 veth_napi_del drivers/net/veth.c:1129 [inline]
 veth_set_features+0x68/0x98 drivers/net/veth.c:1580
 __netdev_update_features+0x200/0x6ec net/core/dev.c:9872
 netdev_update_features+0x28/0x6c net/core/dev.c:9946
 veth_xdp_set drivers/net/veth.c:1681 [inline]
 veth_xdp+0x108/0x224 drivers/net/veth.c:1694
 dev_xdp_install+0x64/0xf8 net/core/dev.c:9243
 dev_xdp_attach+0x250/0x52c net/core/dev.c:9395
 dev_change_xdp_fd+0x16c/0x218 net/core/dev.c:9643
 do_setlink+0xdd0/0xf14 net/core/rtnetlink.c:3132
 rtnl_group_changelink net/core/rtnetlink.c:3452 [inline]
 __rtnl_newlink+0x460/0x898 net/core/rtnetlink.c:3711
 rtnl_newlink+0x50/0x7c net/core/rtnetlink.c:3748
 rtnetlink_rcv_msg+0x12c/0x380 net/core/rtnetlink.c:6615
 netlink_rcv_skb+0x5c/0x128 net/netlink/af_netlink.c:2543
 rtnetlink_rcv+0x18/0x24 net/core/rtnetlink.c:6633
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x2f4/0x360 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0x1a4/0x3e8 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x54/0x60 net/socket.c:745
 ____sys_sendmsg+0x274/0x2ac net/socket.c:2584
 ___sys_sendmsg+0xac/0x100 net/socket.c:2638
 __sys_sendmsg+0x84/0xe0 net/socket.c:2667
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __arm64_sys_sendmsg+0x24/0x30 net/socket.c:2674
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall+0x48/0x114 arch/arm64/kernel/syscall.c:51
 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:136
 do_el0_svc+0x1c/0x28 arch/arm64/kernel/syscall.c:155
 el0_svc+0x34/0xd8 arch/arm64/kernel/entry-common.c:678
 el0t_64_sync_handler+0x100/0x12c arch/arm64/kernel/entry-common.c:696
 el0t_64_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:598
Code: 54fffe8b 91000400 17ffffe6 f9401802 (b9401041) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	54fffe8b 	b.lt	0xffffffffffffffd0  // b.tstop
   4:	91000400 	add	x0, x0, #0x1
   8:	17ffffe6 	b	0xffffffffffffffa0
   c:	f9401802 	ldr	x2, [x0, #48]
* 10:	b9401041 	ldr	w1, [x2, #16] <-- trapping instruction

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/10 16:28 upstream 4a7bbe7519b6 77b23aa1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte BUG: unable to handle kernel NULL pointer dereference in hrtimer_active
* Struck through repros no longer work on HEAD.