================================================================== BUG: KASAN: slab-out-of-bounds in smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:670 Read of size 8 at addr ffff888054abe928 by task kworker/u4:18/15089 CPU: 0 PID: 15089 Comm: kworker/u4:18 Not tainted 5.17.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:670 sk_error_report+0x35/0x310 net/core/sock.c:340 tcp_write_err net/ipv4/tcp_timer.c:71 [inline] tcp_probe_timer net/ipv4/tcp_timer.c:395 [inline] tcp_write_timer_handler+0x437/0xbc0 net/ipv4/tcp_timer.c:626 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x13/0x60 kernel/kcov.c:199 Code: 02 66 0f 1f 44 00 00 48 8b be b0 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 65 8b 05 29 7a 8a 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 <65> 48 8b 14 25 00 70 02 00 a9 00 01 ff 00 74 0e 85 c9 74 35 8b 82 RSP: 0018:ffffc90005f27c90 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff88e76fde RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff88e76fd1 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: 00000000000002a7 rcu_read_unlock include/linux/rcupdate.h:726 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x84e/0xfa0 net/batman-adv/network-coding.c:719 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 23768: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc mm/slab.c:3315 [inline] kmem_cache_alloc+0x265/0x560 mm/slab.c:3499 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags include/linux/audit.h:323 [inline] getname+0x8e/0xd0 fs/namei.c:217 do_sys_openat2+0xf5/0x4d0 fs/open.c:1208 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 23768: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0xff/0x140 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] __cache_free mm/slab.c:3437 [inline] kmem_cache_free.part.0+0x91/0x200 mm/slab.c:3733 putname fs/namei.c:270 [inline] putname+0xfe/0x140 fs/namei.c:256 do_sys_openat2+0x153/0x4d0 fs/open.c:1223 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff888054abec00 which belongs to the cache names_cache of size 4096 The buggy address is located 728 bytes to the left of 4096-byte region [ffff888054abec00, ffff888054abfc00) The buggy address belongs to the page: page:ffffea000152af80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x54abe head:ffffea000152af80 order:1 compound_mapcount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000766588 ffffea0001c76708 ffff88801150d600 raw: 0000000000000000 ffff888054abec00 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 23768, ts 658870529762, free_ts 650344826195 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 __alloc_pages_node include/linux/gfp.h:572 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x390 mm/slab.c:2584 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957 ____cache_alloc mm/slab.c:3040 [inline] ____cache_alloc mm/slab.c:3023 [inline] __do_cache_alloc mm/slab.c:3267 [inline] slab_alloc mm/slab.c:3308 [inline] kmem_cache_alloc+0x450/0x560 mm/slab.c:3499 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags include/linux/audit.h:323 [inline] getname+0x8e/0xd0 fs/namei.c:217 do_sys_openat2+0xf5/0x4d0 fs/open.c:1208 do_sys_open fs/open.c:1230 [inline] __do_sys_openat fs/open.c:1246 [inline] __se_sys_openat fs/open.c:1241 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 slab_destroy mm/slab.c:1630 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1650 cache_flusharray mm/slab.c:3410 [inline] ___cache_free+0x303/0x600 mm/slab.c:3472 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x50/0x1a0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x97/0xb0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc mm/slab.c:3315 [inline] __do_kmalloc mm/slab.c:3692 [inline] __kmalloc+0x27a/0x4d0 mm/slab.c:3703 kmalloc include/linux/slab.h:586 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x1d5/0x590 security/tomoyo/file.c:723 security_file_ioctl+0x50/0xb0 security/security.c:1544 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0xb3/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff888054abe800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888054abe880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888054abe900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888054abe980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888054abea00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 6: 48 8b be b0 01 00 00 mov 0x1b0(%rsi),%rdi d: e8 b4 ff ff ff callq 0xffffffc6 12: 31 c0 xor %eax,%eax 14: c3 retq 15: 90 nop 16: 65 8b 05 29 7a 8a 7e mov %gs:0x7e8a7a29(%rip),%eax # 0x7e8a7a46 1d: 89 c1 mov %eax,%ecx 1f: 48 8b 34 24 mov (%rsp),%rsi 23: 81 e1 00 01 00 00 and $0x100,%ecx * 29: 65 48 8b 14 25 00 70 mov %gs:0x27000,%rdx <-- trapping instruction 30: 02 00 32: a9 00 01 ff 00 test $0xff0100,%eax 37: 74 0e je 0x47 39: 85 c9 test %ecx,%ecx 3b: 74 35 je 0x72 3d: 8b .byte 0x8b 3e: 82 .byte 0x82