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BUG: KASAN: stack-out-of-bounds in jhash2 include/linux/jhash.h:138 [inline]
BUG: KASAN: stack-out-of-bounds in __xfrm6_addr_hash net/xfrm/xfrm_hash.h:16 [inline]
BUG: KASAN: stack-out-of-bounds in __xfrm6_daddr_saddr_hash net/xfrm/xfrm_hash.h:29 [inline]
BUG: KASAN: stack-out-of-bounds in __xfrm_dst_hash+0x399/0x480 net/xfrm/xfrm_hash.h:95
Read of size 4 at addr ffffc90000fa7718 by task syz.6.3857/12877

CPU: 1 PID: 12877 Comm: syz.6.3857 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0xf1/0x140 mm/kasan/report.c:444
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 jhash2 include/linux/jhash.h:138 [inline]
 __xfrm6_addr_hash net/xfrm/xfrm_hash.h:16 [inline]
 __xfrm6_daddr_saddr_hash net/xfrm/xfrm_hash.h:29 [inline]
 __xfrm_dst_hash+0x399/0x480 net/xfrm/xfrm_hash.h:95
 xfrm_dst_hash net/xfrm/xfrm_state.c:63 [inline]
 xfrm_state_find+0x28a/0x2a10 net/xfrm/xfrm_state.c:1092
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2396 [inline]
 xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:2441 [inline]
 xfrm_resolve_and_create_bundle+0x697/0x29f0 net/xfrm/xfrm_policy.c:2734
 xfrm_bundle_lookup net/xfrm/xfrm_policy.c:2969 [inline]
 xfrm_lookup_with_ifid+0x4e9/0x2080 net/xfrm/xfrm_policy.c:3100
 xfrm_lookup net/xfrm/xfrm_policy.c:3197 [inline]
 xfrm_lookup_route+0x3c/0x170 net/xfrm/xfrm_policy.c:3208
 ip_route_output_flow+0x1f8/0x2f0 net/ipv4/route.c:2905
 udp_sendmsg+0x131b/0x21e0 net/ipv4/udp.c:1245
 inet_sendmsg+0xa5/0xc0 net/ipv4/af_inet.c:830
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2435
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2489
 __sys_sendmmsg+0x2ba/0x4e0 net/socket.c:2575
 __do_sys_sendmmsg net/socket.c:2604 [inline]
 __se_sys_sendmmsg net/socket.c:2601 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2601
 x64_sys_call+0x6c6/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa48b3a7dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa489e02028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fa48b620fa0 RCX: 00007fa48b3a7dd9
RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000009
RBP: 00007fa48b43dd69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000810 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa48b621038 R14: 00007fa48b620fa0 R15: 00007ffdcb3e8c58
 </TASK>


addr ffffc90000fa7718 is located in stack of task syz.6.3857/12877 at offset 88 in frame:
 udp_sendmsg+0x0/0x21e0

this frame has 6 objects:
 [32, 88) 'fl4_stack'
 [128, 168) 'ipc'
 [208, 216) 'rt'
 [240, 312) 'opt_copy'
 [352, 356) '__unused_flags'
 [368, 424) 'cork312'

Memory state around the buggy address:
 ffffc90000fa7600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90000fa7680: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
>ffffc90000fa7700: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00 f2 f2 f2
                            ^
 ffffc90000fa7780: f2 f2 00 f2 f2 f2 00 00 00 00 00 00 00 00 00 f2
 ffffc90000fa7800: f2 f2 f2 f2 f8 f2 f8 f8 f8 f8 f8 f8 f8 f3 f3 f3
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