[syzbot] KASAN: use-after-free Read in rdma_listen (3)

From: syzbot
Date: Sat May 01 2021 - 01:49:02 EST


Hello,

syzbot found the following issue on:

HEAD commit: 90c911ad Merge tag 'fixes' of git://git.kernel.org/pub/scm..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14eb4399d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9404cfa686df2c05
dashboard link: https://syzkaller.appspot.com/bug?extid=6bb0528b13611047209c

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6bb0528b13611047209c@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: use-after-free in __list_add_valid+0x93/0xa0 lib/list_debug.c:26
Read of size 8 at addr ffff8881546491e0 by task syz-executor.1/32204

CPU: 1 PID: 32204 Comm: syz-executor.1 Not tainted 5.12.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x141/0x1d7 lib/dump_stack.c:120
print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
__kasan_report mm/kasan/report.c:399 [inline]
kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
__list_add_valid+0x93/0xa0 lib/list_debug.c:26
__list_add include/linux/list.h:67 [inline]
list_add_tail include/linux/list.h:100 [inline]
cma_listen_on_all drivers/infiniband/core/cma.c:2557 [inline]
rdma_listen+0x787/0xe00 drivers/infiniband/core/cma.c:3751
ucma_listen+0x16a/0x210 drivers/infiniband/core/ucma.c:1102
ucma_write+0x259/0x350 drivers/infiniband/core/ucma.c:1732
vfs_write+0x28e/0xa30 fs/read_write.c:603
ksys_write+0x1ee/0x250 fs/read_write.c:658
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb4c3093188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000010 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 00000000004bfbb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd209035df R14: 00007fb4c3093300 R15: 0000000000022000

Allocated by task 32201:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:427 [inline]
____kasan_kmalloc mm/kasan/common.c:506 [inline]
____kasan_kmalloc mm/kasan/common.c:465 [inline]
__kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
kmalloc include/linux/slab.h:554 [inline]
kzalloc include/linux/slab.h:684 [inline]
__rdma_create_id+0x5b/0x550 drivers/infiniband/core/cma.c:844
rdma_create_user_id+0x79/0xd0 drivers/infiniband/core/cma.c:897
ucma_create_id+0x162/0x370 drivers/infiniband/core/ucma.c:461
ucma_write+0x259/0x350 drivers/infiniband/core/ucma.c:1732
vfs_write+0x28e/0xa30 fs/read_write.c:603
ksys_write+0x1ee/0x250 fs/read_write.c:658
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 32201:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
____kasan_slab_free mm/kasan/common.c:360 [inline]
____kasan_slab_free mm/kasan/common.c:325 [inline]
__kasan_slab_free+0xf5/0x130 mm/kasan/common.c:367
kasan_slab_free include/linux/kasan.h:199 [inline]
slab_free_hook mm/slub.c:1562 [inline]
slab_free_freelist_hook+0x92/0x210 mm/slub.c:1600
slab_free mm/slub.c:3161 [inline]
kfree+0xe5/0x7f0 mm/slub.c:4213
ucma_close_id drivers/infiniband/core/ucma.c:185 [inline]
ucma_destroy_private_ctx+0x8b3/0xb70 drivers/infiniband/core/ucma.c:576
ucma_destroy_id+0x1e6/0x280 drivers/infiniband/core/ucma.c:614
ucma_write+0x259/0x350 drivers/infiniband/core/ucma.c:1732
vfs_write+0x28e/0xa30 fs/read_write.c:603
ksys_write+0x1ee/0x250 fs/read_write.c:658
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

Last potentially related work creation:
kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:345
__call_rcu kernel/rcu/tree.c:3039 [inline]
call_rcu+0xb1/0x740 kernel/rcu/tree.c:3114
netlink_release+0xd48/0x1cf0 net/netlink/af_netlink.c:810
__sock_release+0xcd/0x280 net/socket.c:599
sock_close+0x18/0x20 net/socket.c:1258
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:140
exit_task_work include/linux/task_work.h:30 [inline]
do_exit+0xbfc/0x2a60 kernel/exit.c:825
do_group_exit+0x125/0x310 kernel/exit.c:922
__do_sys_exit_group kernel/exit.c:933 [inline]
__se_sys_exit_group kernel/exit.c:931 [inline]
__x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888154649000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 480 bytes inside of
2048-byte region [ffff888154649000, ffff888154649800)
The buggy address belongs to the page:
page:ffffea0005519200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x154648
head:ffffea0005519200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x57ff00000010200(slab|head)
raw: 057ff00000010200 ffffea0005474a00 0000000200000002 ffff888010442000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff888154649080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888154649100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888154649180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888154649200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888154649280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


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