[syzbot] [net?] general protection fault in ip6_ins_rt
From: syzbot <hidden>
Date: 2025-05-19 10:23:33
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Hello, syzbot found the following issue on: HEAD commit: c94d59a126cb Merge tag 'trace-v6.15-rc6' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=100ddcd4580000 kernel config: https://syzkaller.appspot.com/x/.config?x=7819b10245b63b3d dashboard link: https://syzkaller.appspot.com/bug?extid=ce95bbc882771b5d81f7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-c94d59a1.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c62247a68f8a/vmlinux-c94d59a1.xz kernel image: https://storage.googleapis.com/syzbot-assets/4e1db4893db7/bzImage-c94d59a1.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ce95bbc882771b5d81f7@syzkaller.appspotmail.com Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 0 UID: 0 PID: 1136 Comm: kworker/u32:5 Not tainted 6.15.0-rc6-syzkaller-00085-gc94d59a126cb #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:199 Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 e9 0e 29 4d 09 66 66 2e 0f 1f 84 00 00 00 RSP: 0018:ffffc90006d8f818 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000030 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8b6c0863 RDI: dffffc0000000006 RBP: 0000000000000030 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8b6c0863 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880977ea000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbf9f52c6b0 CR3: 0000000065999000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __kasan_check_byte+0x13/0x50 mm/kasan/common.c:556 kasan_check_byte include/linux/kasan.h:399 [inline] lock_acquire kernel/locking/lockdep.c:5840 [inline] lock_acquire+0xfc/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __ip6_ins_rt net/ipv6/route.c:1350 [inline] ip6_ins_rt+0xa1/0x110 net/ipv6/route.c:1361 __ipv6_ifa_notify+0xa6b/0xd60 net/ipv6/addrconf.c:6286 ipv6_ifa_notify net/ipv6/addrconf.c:6325 [inline] addrconf_dad_completed+0x19a/0x10d0 net/ipv6/addrconf.c:4324 addrconf_dad_work+0x84d/0x14e0 net/ipv6/addrconf.c:4272 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:199 Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 e9 0e 29 4d 09 66 66 2e 0f 1f 84 00 00 00 RSP: 0018:ffffc90006d8f818 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: 0000000000000030 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8b6c0863 RDI: dffffc0000000006 RBP: 0000000000000030 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8b6c0863 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880977ea000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbf9f52c6b0 CR3: 0000000065999000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 0f 1f 00 nopl (%rax) 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 66 0f 1f 00 nopw (%rax) 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 c1 ef 03 shr $0x3,%rdi 27: 48 01 c7 add %rax,%rdi * 2a: 0f b6 07 movzbl (%rdi),%eax <-- trapping instruction 2d: 3c 07 cmp $0x7,%al 2f: 0f 96 c0 setbe %al 32: e9 0e 29 4d 09 jmp 0x94d2945 37: 66 data16 38: 66 data16 39: 2e cs 3a: 0f .byte 0xf 3b: 1f (bad) 3c: 84 00 test %al,(%rax) --- This report is generated by a bot. 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