KASAN: slab-out-of-bounds Read in sk_psock_get

Status: fixed on 2023/04/12 21:18
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+1fa91bcd05206ff8cbb5@syzkaller.appspotmail.com
Fix commit: 2a0133723f9e net: fix refcount bug in sk_psock_get (2)
First crash: 1841d, last: 1502d
Cause bisection: introduced by (bisect log) :
commit 130b392c6cd6b2aed1b7eb32253d4920babb4891
Author: Dave Watson <davejwatson@fb.com>
Date: Wed Jan 30 21:58:31 2019 +0000

  net: tls: Add tls 1.3 support

Crash: KASAN: slab-out-of-bounds Read in tls_sw_recvmsg (log)
Repro: C syz .config
  
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (4)
Title Replies (including bot) Last reply
[PATCH v1] net: Add distinct sk_psock field 4 (4) 2022/07/14 13:50
[RFC PATCH 0/1][RESEND] Fix KASAN: slab-out-of-bounds Read in sk_psock_get 5 (5) 2022/07/14 03:58
[RFC PATCH 0/1] Fix KASAN: slab-out-of-bounds Read in sk_psock_get 5 (5) 2022/07/13 18:25
[syzbot] KASAN: slab-out-of-bounds Read in sk_psock_get 0 (1) 2021/08/25 18:42
▶ ▼ Last patch testing requests (11)
Created Duration User Patch Repo Result
2023/02/11 16:32 15m retest repro upstream report log
2023/02/11 15:32 16m retest repro net-next-old report log
2023/02/11 14:32 15m retest repro upstream report log
2022/11/26 02:30 19m retest repro linux-next no crash log
2022/11/03 05:30 17m retest repro net-old no crash log
2022/11/03 05:30 18m retest repro upstream error
2022/11/03 05:30 19m retest repro upstream error
2022/11/03 05:30 17m retest repro net-next-old error
2022/11/03 05:30 18m retest repro upstream error
2022/11/03 05:30 18m retest repro upstream error
2022/07/12 13:16 15m khalid.masum.92@gmail.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ 32346491ddf24599decca06190ebca03ff9de7f8 OK log
▶ ▼ Fix bisection attempts (9)
Created Duration User Patch Repo Result
2022/08/25 14:13 8h10m (2) bisect fix upstream error job log
2022/07/26 04:44 21m bisect fix upstream OK (0) job log log
2022/06/14 15:27 22m bisect fix upstream OK (0) job log log
2022/05/09 11:04 20m bisect fix upstream OK (0) job log log
2022/02/16 11:11 19m bisect fix upstream OK (0) job log log
2022/01/17 10:51 19m bisect fix upstream OK (0) job log log
2021/12/18 10:31 20m bisect fix upstream OK (0) job log log
2021/11/18 10:10 20m bisect fix upstream OK (0) job log log
2021/10/19 09:49 20m bisect fix upstream OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: slab-out-of-bounds in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: slab-out-of-bounds in refcount_read include/linux/refcount.h:147 [inline]
BUG: KASAN: slab-out-of-bounds in __refcount_add_not_zero include/linux/refcount.h:152 [inline]
BUG: KASAN: slab-out-of-bounds in __refcount_inc_not_zero include/linux/refcount.h:227 [inline]
BUG: KASAN: slab-out-of-bounds in refcount_inc_not_zero include/linux/refcount.h:245 [inline]
BUG: KASAN: slab-out-of-bounds in sk_psock_get+0x123/0x410 include/linux/skmsg.h:439
Read of size 4 at addr ffff88807da55e78 by task syz-executor287/3598

CPU: 1 PID: 3598 Comm: syz-executor287 Not tainted 5.18.0-rc6-syzkaller-00153-g2fe1020d73ca #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0xeb/0x467 mm/kasan/report.c:313
 print_report mm/kasan/report.c:429 [inline]
 kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 refcount_read include/linux/refcount.h:147 [inline]
 __refcount_add_not_zero include/linux/refcount.h:152 [inline]
 __refcount_inc_not_zero include/linux/refcount.h:227 [inline]
 refcount_inc_not_zero include/linux/refcount.h:245 [inline]
 sk_psock_get+0x123/0x410 include/linux/skmsg.h:439
 tls_sw_recvmsg+0x195/0x15a0 net/tls/tls_sw.c:1783
 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:671
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:962 [inline]
 ____sys_recvmsg+0x2be/0x5f0 net/socket.c:2632
 ___sys_recvmsg+0x127/0x200 net/socket.c:2674
 do_recvmmsg+0x24d/0x6d0 net/socket.c:2768
 __sys_recvmmsg net/socket.c:2847 [inline]
 __do_sys_recvmmsg net/socket.c:2870 [inline]
 __se_sys_recvmmsg net/socket.c:2863 [inline]
 __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2863
 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
RIP: 0033:0x7fa61bd641c9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdfc46b3c8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa61bd641c9
RDX: 000000000000000a RSI: 00000000200030c0 RDI: 0000000000000005
RBP: 00007fa61bd28370 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000010000 R11: 0000000000000246 R12: 00007fa61bd28400
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 3598:
 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:224 [inline]
 slab_post_alloc_hook mm/slab.h:749 [inline]
 slab_alloc mm/slab.c:3316 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3493 [inline]
 kmem_cache_alloc+0x265/0x560 mm/slab.c:3513
 kmem_cache_zalloc include/linux/slab.h:704 [inline]
 kcm_attach net/kcm/kcmsock.c:1405 [inline]
 kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline]
 kcm_ioctl+0x7f1/0x1180 net/kcm/kcmsock.c:1696
 sock_do_ioctl+0xcc/0x230 net/socket.c:1122
 sock_ioctl+0x2f1/0x640 net/socket.c:1239
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 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

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348
 insert_work+0x48/0x350 kernel/workqueue.c:1358
 __queue_work+0x62e/0x1140 kernel/workqueue.c:1517
 queue_work_on+0xee/0x110 kernel/workqueue.c:1545
 kcm_attach net/kcm/kcmsock.c:1466 [inline]
 kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline]
 kcm_ioctl+0xede/0x1180 net/kcm/kcmsock.c:1696
 sock_do_ioctl+0xcc/0x230 net/socket.c:1122
 sock_ioctl+0x2f1/0x640 net/socket.c:1239
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 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 ffff88807da55bc0
 which belongs to the cache kcm_psock_cache of size 568
The buggy address is located 128 bytes to the right of
 568-byte region [ffff88807da55bc0, ffff88807da55df8)

The buggy address belongs to the physical page:
page:ffffea0001f69500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7da54
head:ffffea0001f69500 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff8880249c7050 ffff8880249c7050 ffff88814bd0c600
raw: 0000000000000000 ffff88807da54040 000000010000000b 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 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 3598, tgid 3598 (syz-executor287), ts 52379940749, free_ts 52358397606
 prep_new_page mm/page_alloc.c:2441 [inline]
 get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408
 __alloc_pages_node include/linux/gfp.h:587 [inline]
 kmem_getpages mm/slab.c:1378 [inline]
 cache_grow_begin+0x75/0x350 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:3309 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3493 [inline]
 kmem_cache_alloc+0x450/0x560 mm/slab.c:3513
 kmem_cache_zalloc include/linux/slab.h:704 [inline]
 kcm_attach net/kcm/kcmsock.c:1405 [inline]
 kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline]
 kcm_ioctl+0x7f1/0x1180 net/kcm/kcmsock.c:1696
 sock_do_ioctl+0xcc/0x230 net/socket.c:1122
 sock_ioctl+0x2f1/0x640 net/socket.c:1239
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 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:1356 [inline]
 free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406
 free_unref_page_prepare mm/page_alloc.c:3328 [inline]
 free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423
 slab_destroy mm/slab.c:1630 [inline]
 slabs_destroy+0x89/0xc0 mm/slab.c:1650
 cache_flusharray mm/slab.c:3411 [inline]
 ___cache_free+0x34e/0x670 mm/slab.c:3474
 qlink_free mm/kasan/quarantine.c:157 [inline]
 qlist_free_all+0x4f/0x1b0 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:224 [inline]
 slab_post_alloc_hook mm/slab.h:749 [inline]
 slab_alloc mm/slab.c:3316 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3493 [inline]
 kmem_cache_alloc+0x265/0x560 mm/slab.c:3513
 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+0xf5/0x4c0 fs/open.c:1207
 do_sys_open fs/open.c:1229 [inline]
 __do_sys_openat fs/open.c:1245 [inline]
 __se_sys_openat fs/open.c:1240 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1240
 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:
 ffff88807da55d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807da55d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc
>ffff88807da55e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff88807da55e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807da55f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/05/15 12:44 upstream 2fe1020d73ca 744a39e2 .config strace log report syz C ci-upstream-kasan-gce-selinux-root KASAN: slab-out-of-bounds Read in sk_psock_get
2022/03/31 09:39 upstream 787af64d05cd 9d49f3a7 .config console log report syz C ci-upstream-kasan-gce-smack-root KASAN: slab-out-of-bounds Read in sk_psock_get
2022/03/06 22:05 upstream dcde98da9970 7bdd8b2c .config console log report syz C ci-upstream-kasan-gce-root KASAN: slab-out-of-bounds Read in sk_psock_get
2021/09/19 08:14 upstream 93ff9f13be91 70b76c1d .config console log report syz C ci-upstream-kasan-gce KASAN: slab-out-of-bounds Read in sk_psock_get
2021/08/21 21:20 net-next-old 4af14dbaeae0 b599f2fc .config console log report syz C ci-upstream-net-kasan-gce KASAN: slab-out-of-bounds Read in sk_psock_get
2021/08/21 19:27 net-old 12d125b4574b b599f2fc .config console log report syz C ci-upstream-net-this-kasan-gce KASAN: slab-out-of-bounds Read in sk_psock_get
2022/04/01 10:46 linux-next e5071887cd22 68fc921a .config console log report syz C ci-upstream-linux-next-kasan-gce-root KASAN: slab-out-of-bounds Read in sk_psock_get
2022/06/25 21:23 net-old 3b89b511ea0c a371c43c .config console log report info ci-upstream-net-this-kasan-gce KASAN: slab-out-of-bounds Read in sk_psock_get
2021/08/21 18:38 net-old 12d125b4574b b599f2fc .config console log report info ci-upstream-net-this-kasan-gce KASAN: slab-out-of-bounds Read in sk_psock_get
* Struck through repros no longer work on HEAD.