syzbot


KASAN: slab-out-of-bounds Read in smc_fback_error_report (2)

Status: auto-obsoleted due to no activity on 2024/03/04 23:35
Reported-by: syzbot+263365d3e5fd395c52b5@syzkaller.appspotmail.com
First crash: 175d, last: 175d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: slab-out-of-bounds Read in smc_fback_error_report 1 334d 334d 0/3 auto-obsoleted due to no activity on 2023/09/28 00:01
upstream KASAN: slab-out-of-bounds Read in smc_fback_error_report net s390 C error 72 752d 828d 22/26 fixed on 2023/02/24 13:50
linux-5.15 KASAN: use-after-free Read in smc_fback_error_report 1 49d 49d 0/3 upstream: reported on 2024/03/30 21:24

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in smc_fback_error_report+0x6d/0x90 net/smc/af_smc.c:652
Read of size 8 at addr ffff8880973e9ab8 by task syz-executor.1/3556

CPU: 1 PID: 3556 Comm: syz-executor.1 Not tainted 5.15.139-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 smc_fback_error_report+0x6d/0x90 net/smc/af_smc.c:652
 sk_error_report+0x3b/0x260 net/core/sock.c:339
 tcp_write_err net/ipv4/tcp_timer.c:71 [inline]
 tcp_probe_timer net/ipv4/tcp_timer.c:396 [inline]
 tcp_write_timer_handler+0x6d9/0x9c0 net/ipv4/tcp_timer.c:648
 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:664
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1737
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: b1 7e f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ee 89 3d f7 48 89 df e8 46 dd 3e f7 e8 11 8b 61 f7 fb bf 01 00 00 00 <e8> 26 1a 32 f7 65 8b 05 b7 55 dd 75 85 c0 74 02 5b c3 e8 44 6d db
RSP: 0018:ffffc90002ebf848 EFLAGS: 00000286
RAX: 6e5dbcf4aa85f000 RBX: ffff88801bba0990 RCX: ffffffff913c6003
RDX: dffffc0000000000 RSI: ffffffff8a8b0be0 RDI: 0000000000000001
RBP: ffff88801bba0988 R08: ffffffff8186a540 R09: ffffed1003774133
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0002aadac0
R13: 00fff00000080035 R14: ffffea0002aadac8 R15: ffffea0002aadac0
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 delete_from_page_cache+0x12e/0x190 mm/filemap.c:267
 truncate_inode_page+0x8d/0xb0 mm/truncate.c:219
 shmem_undo_range+0x535/0x1b50 mm/shmem.c:960
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x21b/0xa00 mm/shmem.c:1145
 evict+0x2a4/0x620 fs/inode.c:587
 __dentry_kill+0x436/0x650 fs/dcache.c:582
 dentry_kill+0xbb/0x290
 dput+0x1f1/0x420 fs/dcache.c:888
 __fput+0x5ec/0x890 fs/file_table.c:288
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f1f23dcbe17
Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fffb9fdf0f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f1f23dcbe17
RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007fffb9fdf1b0
RBP: 00007fffb9fdf1b0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffb9fe0270
R13: 00007f1f23e153b9 R14: 0000000000105844 R15: 0000000000000014
 </TASK>

Allocated by task 3593:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 __kmalloc_node_track_caller+0x195/0x390 mm/slub.c:4963
 kmalloc_reserve net/core/skbuff.c:356 [inline]
 __alloc_skb+0x12c/0x590 net/core/skbuff.c:427
 alloc_skb include/linux/skbuff.h:1167 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
 nsim_dev_trap_report_work+0x25e/0xab0 drivers/net/netdevsim/dev.c:762
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Freed by task 3593:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 skb_free_head net/core/skbuff.c:655 [inline]
 skb_release_data+0x73a/0x8a0 net/core/skbuff.c:677
 skb_release_all net/core/skbuff.c:742 [inline]
 __kfree_skb net/core/skbuff.c:756 [inline]
 consume_skb+0xa3/0x140 net/core/skbuff.c:914
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:737 [inline]
 nsim_dev_trap_report_work+0x788/0xab0 drivers/net/netdevsim/dev.c:762
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

The buggy address belongs to the object at ffff8880973e8000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 2744 bytes to the right of
 4096-byte region [ffff8880973e8000, ffff8880973e9000)
The buggy address belongs to the page:
page:ffffea00025cfa00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x973e8
head:ffffea00025cfa00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011c42140
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 3593, ts 1063572554228, free_ts 1063457321658
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 __kmalloc_node_track_caller+0x1f6/0x390 mm/slub.c:4958
 kmalloc_reserve net/core/skbuff.c:356 [inline]
 __alloc_skb+0x12c/0x590 net/core/skbuff.c:427
 alloc_skb include/linux/skbuff.h:1167 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
 nsim_dev_trap_report_work+0x25e/0xab0 drivers/net/netdevsim/dev.c:762
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_slab mm/slub.c:2015 [inline]
 discard_slab mm/slub.c:2021 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507
 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587
 do_slab_free mm/slub.c:3487 [inline]
 ___cache_free+0xe3/0x100 mm/slub.c:3506
 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 __kmalloc+0x120/0x300 mm/slub.c:4403
 kmalloc include/linux/slab.h:596 [inline]
 tomoyo_realpath_from_path+0xd8/0x5e0 security/tomoyo/realpath.c:254
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x273/0x6b0 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x120 security/security.c:1348
 vfs_getattr+0x26/0x360 fs/stat.c:157
 vfs_statx+0x18f/0x3b0 fs/stat.c:225
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:411 [inline]
 __se_sys_newfstatat fs/stat.c:405 [inline]
 __x64_sys_newfstatat+0x12c/0x1b0 fs/stat.c:405

Memory state around the buggy address:
 ffff8880973e9980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880973e9a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880973e9a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                        ^
 ffff8880973e9b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880973e9b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	b1 7e                	mov    $0x7e,%cl
   2:	f6 ff                	idiv   %bh
   4:	90                   	nop
   5:	53                   	push   %rbx
   6:	48 89 fb             	mov    %rdi,%rbx
   9:	48 83 c7 18          	add    $0x18,%rdi
   d:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
  12:	e8 ee 89 3d f7       	call   0xf73d8a05
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 46 dd 3e f7       	call   0xf73edd65
  1f:	e8 11 8b 61 f7       	call   0xf7618b35
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 26 1a 32 f7       	call   0xf7321a55 <-- trapping instruction
  2f:	65 8b 05 b7 55 dd 75 	mov    %gs:0x75dd55b7(%rip),%eax        # 0x75dd55ed
  36:	85 c0                	test   %eax,%eax
  38:	74 02                	je     0x3c
  3a:	5b                   	pop    %rbx
  3b:	c3                   	ret
  3c:	e8                   	.byte 0xe8
  3d:	44 6d                	rex.R insl (%dx),%es:(%rdi)
  3f:	db                   	.byte 0xdb

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/25 23:35 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in smc_fback_error_report
* Struck through repros no longer work on HEAD.