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WARNING in ip_rt_bug (4)

Status: upstream: reported C repro on 2025/09/08 02:20
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+076f99a5286d95054742@syzkaller.appspotmail.com
First crash: 5d05h, last: 5d05h
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/09/09 upstream (ToT) f777d1112ee5 C [report] unregister_netdevice: waiting for DEV to become free
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING in ip_rt_bug -1 C error 2 1440d 1988d 0/1 upstream: reported C repro on 2020/04/03 11:53
linux-4.14 WARNING in ip_rt_bug -1 C inconclusive 1 1917d 1977d 0/1 upstream: reported C repro on 2020/04/15 03:43
linux-6.1 WARNING in ip_rt_bug (2) -1 1 527d 527d 0/3 auto-obsoleted due to no activity on 2024/07/13 04:22
linux-6.1 WARNING in ip_rt_bug -1 1 758d 758d 0/3 auto-obsoleted due to no activity on 2023/11/25 06:32
upstream WARNING in ip_rt_bug (2) net -1 C done error 436 4d16h 1066d 0/29 upstream: reported C repro on 2022/10/12 18:26
linux-5.15 WARNING in ip_rt_bug -1 7 130d 250d 0/3 auto-obsoleted due to no activity on 2025/08/13 17:11
upstream WARNING in ip_rt_bug net -1 1 2721d 2714d 0/29 auto-closed as invalid on 2019/02/22 10:34
linux-6.1 WARNING in ip_rt_bug (3) -1 26 98d 266d 0/3 auto-obsoleted due to no activity on 2025/09/07 04:48

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4904 at net/ipv4/route.c:1278 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 4904 at net/ipv4/route.c:1278 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
Modules linked in:
CPU: 0 PID: 4904 Comm: syz.0.408 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ip_rt_bug+0x30/0xf8 include/linux/skbuff.h:1220
lr : kfree_skb include/linux/skbuff.h:1220 [inline]
lr : ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
sp : ffff8000080075c0
x29: ffff8000080075c0 x28: 1ffff00001000ef8 x27: ffff0000ed990500
x26: dfff800000000000 x25: 1fffe0001db320ab x24: dfff800000000000
x23: ffff0000ce86e600 x22: ffff0000ce86e630 x21: ffff0000c4fb8d00
x20: ffff0000ed990500 x19: ffff0000ed990500 x18: 0000000000000000
x17: ffff8000181f9000 x16: ffff8000082d22d4 x15: ffff80000fd818b0
x14: ffff80001051e60c x13: ffff80000fd80f00 x12: 0000000000ff0100
x11: ff0080000a8935f4 x10: 0000000000000003 x9 : a8cfd419ac140c00
x8 : a8cfd419ac140c00 x7 : ffff8000083af900 x6 : ffff80000fd80f00
x5 : ffff0000d940b628 x4 : ffff800008007270 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff800011abd7c0 x0 : 0000000000000000
Call trace:
 kfree_skb include/linux/skbuff.h:1220 [inline]
 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x134/0x2b0 net/ipv4/ip_output.c:1600
 ip_push_pending_frames+0x6c/0x88 net/ipv4/ip_output.c:1620
 icmp_push_reply+0x2e0/0x3c0 net/ipv4/icmp.c:399
 __icmp_send+0xbd4/0xfc4 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1258 [inline]
 ipv4_link_failure+0x54c/0x8b0 net/ipv4/route.c:1265
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x11c/0x16c net/ipv4/arp.c:296
 neigh_invalidate+0x29c/0x4ac net/core/neighbour.c:1064
 neigh_timer_handler+0x704/0xe18 net/core/neighbour.c:1151
 call_timer_fn+0x1b8/0x964 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x460/0x6bc kernel/time/timer.c:1820
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833
 handle_softirqs+0x318/0xc6c kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x43c kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 vsnprintf+0x10b0/0x1890 lib/vsprintf.c:2805
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x148/0x22c fs/seq_file.c:406
 c_show+0x40/0x3f8 crypto/proc.c:40
 seq_read_iter+0x858/0xc00 fs/seq_file.c:272
 proc_reg_read_iter+0x184/0x2b0 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2259 [inline]
 generic_file_splice_read+0x160/0x404 fs/splice.c:308
 do_splice_to fs/splice.c:803 [inline]
 splice_direct_to_actor+0x300/0x978 fs/splice.c:875
 do_splice_direct+0x158/0x244 fs/splice.c:1002
 do_sendfile+0x458/0xc88 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __arm64_sys_sendfile64+0x130/0x360 fs/read_write.c:1309
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 1921
hardirqs last  enabled at (1920): [<ffff8000088d764c>] kasan_quarantine_put+0xc4/0x204 mm/kasan/quarantine.c:242
hardirqs last disabled at (1921): [<ffff800011956c70>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (1638): [<ffff80000fcc2cb8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1638): [<ffff80000fcc2cb8>] release_sock+0x16c/0x1bc net/core/sock.c:3514
softirqs last disabled at (1643): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4904 at net/ipv4/route.c:1278 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 4904 at net/ipv4/route.c:1278 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
Modules linked in:
CPU: 0 PID: 4904 Comm: syz.0.408 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ip_rt_bug+0x30/0xf8 include/linux/skbuff.h:1220
lr : kfree_skb include/linux/skbuff.h:1220 [inline]
lr : ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
sp : ffff8000080075c0
x29: ffff8000080075c0 x28: 1ffff00001000ef8 x27: ffff0000ed990640
x26: dfff800000000000 x25: 1fffe0001db320d3 x24: dfff800000000000
x23: ffff0000ce86e600 x22: ffff0000ce86e630 x21: ffff0000c4fb8d00
x20: ffff0000ed990640 x19: ffff0000ed990640 x18: 0000000036b6d8fa
x17: dfff800000000000 x16: ffff8000082d22d4 x15: 0000000000000000
x14: 00000000081a8e9c x13: 0000000031cf6a47 x12: 0000000000ff0100
x11: ff0080000a8935f4 x10: 0000000000000003 x9 : a8cfd419ac140c00
x8 : a8cfd419ac140c00 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff800011abd7c0 x0 : 0000000000000000
Call trace:
 kfree_skb include/linux/skbuff.h:1220 [inline]
 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x134/0x2b0 net/ipv4/ip_output.c:1600
 ip_push_pending_frames+0x6c/0x88 net/ipv4/ip_output.c:1620
 icmp_push_reply+0x2e0/0x3c0 net/ipv4/icmp.c:399
 __icmp_send+0xbd4/0xfc4 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1258 [inline]
 ipv4_link_failure+0x54c/0x8b0 net/ipv4/route.c:1265
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x11c/0x16c net/ipv4/arp.c:296
 neigh_invalidate+0x29c/0x4ac net/core/neighbour.c:1064
 neigh_timer_handler+0x704/0xe18 net/core/neighbour.c:1151
 call_timer_fn+0x1b8/0x964 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x460/0x6bc kernel/time/timer.c:1820
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833
 handle_softirqs+0x318/0xc6c kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x43c kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 vsnprintf+0x10b0/0x1890 lib/vsprintf.c:2805
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x148/0x22c fs/seq_file.c:406
 c_show+0x40/0x3f8 crypto/proc.c:40
 seq_read_iter+0x858/0xc00 fs/seq_file.c:272
 proc_reg_read_iter+0x184/0x2b0 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2259 [inline]
 generic_file_splice_read+0x160/0x404 fs/splice.c:308
 do_splice_to fs/splice.c:803 [inline]
 splice_direct_to_actor+0x300/0x978 fs/splice.c:875
 do_splice_direct+0x158/0x244 fs/splice.c:1002
 do_sendfile+0x458/0xc88 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __arm64_sys_sendfile64+0x130/0x360 fs/read_write.c:1309
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 2231
hardirqs last  enabled at (2230): [<ffff8000088d764c>] kasan_quarantine_put+0xc4/0x204 mm/kasan/quarantine.c:242
hardirqs last disabled at (2231): [<ffff800011956c70>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (1638): [<ffff80000fcc2cb8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1638): [<ffff80000fcc2cb8>] release_sock+0x16c/0x1bc net/core/sock.c:3514
softirqs last disabled at (1643): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4904 at net/ipv4/route.c:1278 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 4904 at net/ipv4/route.c:1278 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
Modules linked in:
CPU: 0 PID: 4904 Comm: syz.0.408 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ip_rt_bug+0x30/0xf8 include/linux/skbuff.h:1220
lr : kfree_skb include/linux/skbuff.h:1220 [inline]
lr : ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
sp : ffff8000080075c0
x29: ffff8000080075c0 x28: 1ffff00001000ef8 x27: ffff0000ed990780
x26: dfff800000000000 x25: 1fffe0001db320fb x24: dfff800000000000
x23: ffff0000ce86e600 x22: ffff0000ce86e630 x21: ffff0000c4fb8d00
x20: ffff0000ed990780 x19: ffff0000ed990780 x18: 0000000036b6d8fa
x17: dfff800000000000 x16: ffff8000082d22d4 x15: 0000000000000000
x14: 00000000081a8e9c x13: 0000000031cf6a47 x12: 0000000000ff0100
x11: ff0080000a8935f4 x10: 0000000000000003 x9 : a8cfd419ac140c00
x8 : a8cfd419ac140c00 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff800011abd7c0 x0 : 0000000000000000
Call trace:
 kfree_skb include/linux/skbuff.h:1220 [inline]
 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x134/0x2b0 net/ipv4/ip_output.c:1600
 ip_push_pending_frames+0x6c/0x88 net/ipv4/ip_output.c:1620
 icmp_push_reply+0x2e0/0x3c0 net/ipv4/icmp.c:399
 __icmp_send+0xbd4/0xfc4 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1258 [inline]
 ipv4_link_failure+0x54c/0x8b0 net/ipv4/route.c:1265
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x11c/0x16c net/ipv4/arp.c:296
 neigh_invalidate+0x29c/0x4ac net/core/neighbour.c:1064
 neigh_timer_handler+0x704/0xe18 net/core/neighbour.c:1151
 call_timer_fn+0x1b8/0x964 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x460/0x6bc kernel/time/timer.c:1820
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833
 handle_softirqs+0x318/0xc6c kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x43c kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 vsnprintf+0x10b0/0x1890 lib/vsprintf.c:2805
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x148/0x22c fs/seq_file.c:406
 c_show+0x40/0x3f8 crypto/proc.c:40
 seq_read_iter+0x858/0xc00 fs/seq_file.c:272
 proc_reg_read_iter+0x184/0x2b0 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2259 [inline]
 generic_file_splice_read+0x160/0x404 fs/splice.c:308
 do_splice_to fs/splice.c:803 [inline]
 splice_direct_to_actor+0x300/0x978 fs/splice.c:875
 do_splice_direct+0x158/0x244 fs/splice.c:1002
 do_sendfile+0x458/0xc88 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __arm64_sys_sendfile64+0x130/0x360 fs/read_write.c:1309
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 2533
hardirqs last  enabled at (2532): [<ffff8000088d764c>] kasan_quarantine_put+0xc4/0x204 mm/kasan/quarantine.c:242
hardirqs last disabled at (2533): [<ffff800011956c70>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (1638): [<ffff80000fcc2cb8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1638): [<ffff80000fcc2cb8>] release_sock+0x16c/0x1bc net/core/sock.c:3514
softirqs last disabled at (1643): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5055 at net/ipv4/route.c:1278 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 5055 at net/ipv4/route.c:1278 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
Modules linked in:
CPU: 0 PID: 5055 Comm: syz.0.559 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ip_rt_bug+0x30/0xf8 include/linux/skbuff.h:1220
lr : kfree_skb include/linux/skbuff.h:1220 [inline]
lr : ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
sp : ffff8000080075c0
x29: ffff8000080075c0 x28: 1ffff00001000ef8 x27: ffff0000daadfa00
x26: dfff800000000000 x25: 1fffe0001b55bf4b x24: dfff800000000000
x23: ffff0000d064d200 x22: ffff0000d064d230 x21: ffff0000c4fb8d00
x20: ffff0000daadfa00 x19: ffff0000daadfa00 x18: 0000000000000000
x17: ffff8000181f9000 x16: ffff8000082d22d4 x15: 0000000000000000
x14: 00000000081a8e9c x13: 0000000031cf6a47 x12: 0000000000ff0100
x11: ff0080000a8935f4 x10: 0000000000000003 x9 : f690bb1d63e78b00
x8 : f690bb1d63e78b00 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff800011abd7c0 x0 : 0000000000000000
Call trace:
 kfree_skb include/linux/skbuff.h:1220 [inline]
 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x134/0x2b0 net/ipv4/ip_output.c:1600
 ip_push_pending_frames+0x6c/0x88 net/ipv4/ip_output.c:1620
 icmp_push_reply+0x2e0/0x3c0 net/ipv4/icmp.c:399
 __icmp_send+0xbd4/0xfc4 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1258 [inline]
 ipv4_link_failure+0x54c/0x8b0 net/ipv4/route.c:1265
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x11c/0x16c net/ipv4/arp.c:296
 neigh_invalidate+0x29c/0x4ac net/core/neighbour.c:1064
 neigh_timer_handler+0x704/0xe18 net/core/neighbour.c:1151
 call_timer_fn+0x1b8/0x964 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x460/0x6bc kernel/time/timer.c:1820
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833
 handle_softirqs+0x318/0xc6c kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x43c kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 __sanitizer_cov_trace_switch+0x10/0xf4 kernel/kcov.c:332
 vsnprintf+0xd0/0x1890 lib/vsprintf.c:2757
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x148/0x22c fs/seq_file.c:406
 crypto_shash_show+0x5c/0xc8 crypto/shash.c:490
 c_show+0x1d8/0x3f8 crypto/proc.c:59
 seq_read_iter+0x858/0xc00 fs/seq_file.c:272
 proc_reg_read_iter+0x184/0x2b0 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2259 [inline]
 generic_file_splice_read+0x160/0x404 fs/splice.c:308
 do_splice_to fs/splice.c:803 [inline]
 splice_direct_to_actor+0x300/0x978 fs/splice.c:875
 do_splice_direct+0x158/0x244 fs/splice.c:1002
 do_sendfile+0x458/0xc88 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __arm64_sys_sendfile64+0x130/0x360 fs/read_write.c:1309
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 1819
hardirqs last  enabled at (1818): [<ffff8000088d764c>] kasan_quarantine_put+0xc4/0x204 mm/kasan/quarantine.c:242
hardirqs last disabled at (1819): [<ffff800011956c70>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (1564): [<ffff80000fcc2cb8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1564): [<ffff80000fcc2cb8>] release_sock+0x16c/0x1bc net/core/sock.c:3514
softirqs last disabled at (1569): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5055 at net/ipv4/route.c:1278 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 5055 at net/ipv4/route.c:1278 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
Modules linked in:
CPU: 0 PID: 5055 Comm: syz.0.559 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ip_rt_bug+0x30/0xf8 include/linux/skbuff.h:1220
lr : kfree_skb include/linux/skbuff.h:1220 [inline]
lr : ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
sp : ffff8000080075c0
x29: ffff8000080075c0 x28: 1ffff00001000ef8 x27: ffff0000daadf8c0
x26: dfff800000000000 x25: 1fffe0001b55bf23 x24: dfff800000000000
x23: ffff0000d064d200 x22: ffff0000d064d230 x21: ffff0000c4fb8d00
x20: ffff0000daadf8c0 x19: ffff0000daadf8c0 x18: 0000000000000000
x17: ffff8000181f9000 x16: ffff8000082d22d4 x15: 0000000000000000
x14: 00000000081a8e9c x13: 0000000031cf6a47 x12: 0000000000ff0100
x11: ff0080000a8935f4 x10: 0000000000000003 x9 : f690bb1d63e78b00
x8 : f690bb1d63e78b00 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff800011abd7c0 x0 : 0000000000000000
Call trace:
 kfree_skb include/linux/skbuff.h:1220 [inline]
 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x134/0x2b0 net/ipv4/ip_output.c:1600
 ip_push_pending_frames+0x6c/0x88 net/ipv4/ip_output.c:1620
 icmp_push_reply+0x2e0/0x3c0 net/ipv4/icmp.c:399
 __icmp_send+0xbd4/0xfc4 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1258 [inline]
 ipv4_link_failure+0x54c/0x8b0 net/ipv4/route.c:1265
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x11c/0x16c net/ipv4/arp.c:296
 neigh_invalidate+0x29c/0x4ac net/core/neighbour.c:1064
 neigh_timer_handler+0x704/0xe18 net/core/neighbour.c:1151
 call_timer_fn+0x1b8/0x964 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x460/0x6bc kernel/time/timer.c:1820
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833
 handle_softirqs+0x318/0xc6c kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x43c kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 __sanitizer_cov_trace_switch+0x10/0xf4 kernel/kcov.c:332
 vsnprintf+0xd0/0x1890 lib/vsprintf.c:2757
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x148/0x22c fs/seq_file.c:406
 crypto_shash_show+0x5c/0xc8 crypto/shash.c:490
 c_show+0x1d8/0x3f8 crypto/proc.c:59
 seq_read_iter+0x858/0xc00 fs/seq_file.c:272
 proc_reg_read_iter+0x184/0x2b0 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2259 [inline]
 generic_file_splice_read+0x160/0x404 fs/splice.c:308
 do_splice_to fs/splice.c:803 [inline]
 splice_direct_to_actor+0x300/0x978 fs/splice.c:875
 do_splice_direct+0x158/0x244 fs/splice.c:1002
 do_sendfile+0x458/0xc88 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __arm64_sys_sendfile64+0x130/0x360 fs/read_write.c:1309
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 2115
hardirqs last  enabled at (2114): [<ffff8000088d764c>] kasan_quarantine_put+0xc4/0x204 mm/kasan/quarantine.c:242
hardirqs last disabled at (2115): [<ffff800011956c70>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (1564): [<ffff80000fcc2cb8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1564): [<ffff80000fcc2cb8>] release_sock+0x16c/0x1bc net/core/sock.c:3514
softirqs last disabled at (1569): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5055 at net/ipv4/route.c:1278 kfree_skb include/linux/skbuff.h:1220 [inline]
WARNING: CPU: 0 PID: 5055 at net/ipv4/route.c:1278 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
Modules linked in:
CPU: 0 PID: 5055 Comm: syz.0.559 Tainted: G        W          syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 62400005 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : ip_rt_bug+0x30/0xf8 include/linux/skbuff.h:1220
lr : kfree_skb include/linux/skbuff.h:1220 [inline]
lr : ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
sp : ffff8000080075c0
x29: ffff8000080075c0 x28: 1ffff00001000ef8 x27: ffff0000daadf780
x26: dfff800000000000 x25: 1fffe0001b55befb x24: dfff800000000000
x23: ffff0000d064d200 x22: ffff0000d064d230 x21: ffff0000c4fb8d00
x20: ffff0000daadf780 x19: ffff0000daadf780 x18: 0000000000000000
x17: ffff8000181f9000 x16: ffff8000082d22d4 x15: 0000000000000000
x14: 00000000081a8e9c x13: 0000000031cf6a47 x12: 0000000000ff0100
x11: ff0080000a8935f4 x10: 0000000000000003 x9 : f690bb1d63e78b00
x8 : f690bb1d63e78b00 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : ffff800011abd7c0 x0 : 0000000000000000
Call trace:
 kfree_skb include/linux/skbuff.h:1220 [inline]
 ip_rt_bug+0x30/0xf8 net/ipv4/route.c:1277
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x134/0x2b0 net/ipv4/ip_output.c:1600
 ip_push_pending_frames+0x6c/0x88 net/ipv4/ip_output.c:1620
 icmp_push_reply+0x2e0/0x3c0 net/ipv4/icmp.c:399
 __icmp_send+0xbd4/0xfc4 net/ipv4/icmp.c:785
 ipv4_send_dest_unreach net/ipv4/route.c:1258 [inline]
 ipv4_link_failure+0x54c/0x8b0 net/ipv4/route.c:1265
 dst_link_failure include/net/dst.h:423 [inline]
 arp_error_report+0x11c/0x16c net/ipv4/arp.c:296
 neigh_invalidate+0x29c/0x4ac net/core/neighbour.c:1064
 neigh_timer_handler+0x704/0xe18 net/core/neighbour.c:1151
 call_timer_fn+0x1b8/0x964 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x460/0x6bc kernel/time/timer.c:1820
 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1833
 handle_softirqs+0x318/0xc6c kernel/softirq.c:596
 __do_softirq+0x14/0x20 kernel/softirq.c:630
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:80
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:897
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:85
 invoke_softirq kernel/softirq.c:477 [inline]
 __irq_exit_rcu+0x23c/0x43c kernel/softirq.c:679
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:691
 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline]
 el1_interrupt+0x38/0x54 arch/arm64/kernel/entry-common.c:486
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581
 __sanitizer_cov_trace_switch+0x10/0xf4 kernel/kcov.c:332
 vsnprintf+0xd0/0x1890 lib/vsprintf.c:2757
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x148/0x22c fs/seq_file.c:406
 crypto_shash_show+0x5c/0xc8 crypto/shash.c:490
 c_show+0x1d8/0x3f8 crypto/proc.c:59
 seq_read_iter+0x858/0xc00 fs/seq_file.c:272
 proc_reg_read_iter+0x184/0x2b0 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:2259 [inline]
 generic_file_splice_read+0x160/0x404 fs/splice.c:308
 do_splice_to fs/splice.c:803 [inline]
 splice_direct_to_actor+0x300/0x978 fs/splice.c:875
 do_splice_direct+0x158/0x244 fs/splice.c:1002
 do_sendfile+0x458/0xc88 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __arm64_sys_sendfile64+0x130/0x360 fs/read_write.c:1309
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
irq event stamp: 2421
hardirqs last  enabled at (2420): [<ffff8000088d764c>] kasan_quarantine_put+0xc4/0x204 mm/kasan/quarantine.c:242
hardirqs last disabled at (2421): [<ffff800011956c70>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:405
softirqs last  enabled at (1564): [<ffff80000fcc2cb8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (1564): [<ffff80000fcc2cb8>] release_sock+0x16c/0x1bc net/core/sock.c:3514
softirqs last disabled at (1569): [<ffff800008020164>] __do_softirq+0x14/0x20 kernel/softirq.c:630
---[ end trace 0000000000000000 ]---

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/08 02:19 linux-6.1.y 28c695c365e1 d291dd2d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in ip_rt_bug
* Struck through repros no longer work on HEAD.