* KASAN: use-after-free Read in ib_uverbs_remove_one
@ 2020-05-28 14:33 syzbot
[not found] ` <20200529083126.15808-1-hdanton@sina.com>
2020-05-30 0:13 ` Jason Gunthorpe
0 siblings, 2 replies; 3+ messages in thread
From: syzbot @ 2020-05-28 14:33 UTC (permalink / raw)
To: dledford, jgg, leon, linux-kernel, linux-rdma, michal.kalderon,
syzkaller-bugs, yishaih
Hello,
syzbot found the following crash on:
HEAD commit: c11d28ab Add linux-next specific files for 20200522
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=12fc3e72100000
kernel config: https://syzkaller.appspot.com/x/.config?x=3f6dbdea4159fb66
dashboard link: https://syzkaller.appspot.com/bug?extid=478fd0d54412b8759e0d
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+478fd0d54412b8759e0d@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in ib_uverbs_remove_one+0x411/0x4e0 drivers/infiniband/core/uverbs_main.c:1210
Read of size 4 at addr ffff888096324578 by task syz-executor.2/15847
CPU: 1 PID: 15847 Comm: syz-executor.2 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x18f/0x20d lib/dump_stack.c:118
print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
__kasan_report mm/kasan/report.c:513 [inline]
kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
ib_uverbs_remove_one+0x411/0x4e0 drivers/infiniband/core/uverbs_main.c:1210
remove_client_context+0xbe/0x110 drivers/infiniband/core/device.c:732
disable_device+0x13b/0x230 drivers/infiniband/core/device.c:1278
__ib_unregister_device+0x91/0x180 drivers/infiniband/core/device.c:1445
ib_unregister_device_and_put+0x57/0x80 drivers/infiniband/core/device.c:1508
nldev_dellink+0x20a/0x310 drivers/infiniband/core/nldev.c:1571
rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0x586/0x900 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:672
____sys_sendmsg+0x6e6/0x810 net/socket.c:2352
___sys_sendmsg+0x100/0x170 net/socket.c:2406
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd6764d1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004ffa00 RCX: 000000000045ca29
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000009af R14: 00000000004d61b0 R15: 00007fd6764d26d4
Allocated by task 9061:
save_stack+0x1b/0x40 mm/kasan/common.c:48
set_track mm/kasan/common.c:56 [inline]
__kasan_kmalloc mm/kasan/common.c:494 [inline]
__kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
kmalloc include/linux/slab.h:555 [inline]
kzalloc include/linux/slab.h:669 [inline]
ib_uverbs_add_one+0x80/0x7c0 drivers/infiniband/core/uverbs_main.c:1107
add_client_context+0x400/0x5e0 drivers/infiniband/core/device.c:677
enable_device_and_get+0x1cd/0x3b0 drivers/infiniband/core/device.c:1326
ib_register_device drivers/infiniband/core/device.c:1392 [inline]
ib_register_device+0xa12/0xda0 drivers/infiniband/core/device.c:1353
siw_device_register drivers/infiniband/sw/siw/siw_main.c:70 [inline]
siw_newlink drivers/infiniband/sw/siw/siw_main.c:565 [inline]
siw_newlink+0xd37/0x1240 drivers/infiniband/sw/siw/siw_main.c:542
nldev_newlink+0x29e/0x420 drivers/infiniband/core/nldev.c:1541
rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0x586/0x900 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:672
____sys_sendmsg+0x6e6/0x810 net/socket.c:2352
___sys_sendmsg+0x100/0x170 net/socket.c:2406
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
Freed by task 15847:
save_stack+0x1b/0x40 mm/kasan/common.c:48
set_track mm/kasan/common.c:56 [inline]
kasan_set_free_info mm/kasan/common.c:316 [inline]
__kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
__cache_free mm/slab.c:3426 [inline]
kfree+0x109/0x2b0 mm/slab.c:3757
device_release+0x71/0x200 drivers/base/core.c:1541
kobject_cleanup lib/kobject.c:701 [inline]
kobject_release lib/kobject.c:732 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1c8/0x2f0 lib/kobject.c:749
cdev_device_del+0x69/0x80 fs/char_dev.c:575
ib_uverbs_remove_one+0x31/0x4e0 drivers/infiniband/core/uverbs_main.c:1209
remove_client_context+0xbe/0x110 drivers/infiniband/core/device.c:732
disable_device+0x13b/0x230 drivers/infiniband/core/device.c:1278
__ib_unregister_device+0x91/0x180 drivers/infiniband/core/device.c:1445
ib_unregister_device_and_put+0x57/0x80 drivers/infiniband/core/device.c:1508
nldev_dellink+0x20a/0x310 drivers/infiniband/core/nldev.c:1571
rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0x586/0x900 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
sock_sendmsg_nosec net/socket.c:652 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:672
____sys_sendmsg+0x6e6/0x810 net/socket.c:2352
___sys_sendmsg+0x100/0x170 net/socket.c:2406
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
The buggy address belongs to the object at ffff888096324000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1400 bytes inside of
4096-byte region [ffff888096324000, ffff888096325000)
The buggy address belongs to the page:
page:ffffea000258c900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea000258c900 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea0002429c08 ffffea000173f988 ffff8880aa002000
raw: 0000000000000000 ffff888096324000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888096324400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888096324480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888096324500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888096324580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888096324600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: KASAN: use-after-free Read in ib_uverbs_remove_one
[not found] ` <20200529083126.15808-1-hdanton@sina.com>
@ 2020-05-29 13:09 ` Jason Gunthorpe
0 siblings, 0 replies; 3+ messages in thread
From: Jason Gunthorpe @ 2020-05-29 13:09 UTC (permalink / raw)
To: Hillf Danton
Cc: syzbot, dledford, leon, linux-kernel, linux-rdma,
michal.kalderon, syzkaller-bugs, yishaih
On Fri, May 29, 2020 at 04:31:26PM +0800, Hillf Danton wrote:
> Hold another grab to dev to prevent it from going home before work gets
> done with it.
>
> +++ b/drivers/infiniband/core/uverbs_main.c
> @@ -1152,6 +1152,8 @@ static int ib_uverbs_add_one(struct ib_d
> device->ops.mmap ? &uverbs_mmap_fops : &uverbs_fops);
> uverbs_dev->cdev.owner = THIS_MODULE;
>
> + /* pair with put_device() in ib_uverbs_remove_one() */
> + get_device(&uverbs_dev->dev);
> ret = cdev_device_add(&uverbs_dev->cdev, &uverbs_dev->dev);
> if (ret)
> goto err_uapi;
Doesn't look right, the put_device() in uverbs_remove_one() pairs with
the device_initialize() in this function.
The only thing I can think of is we called remove_once twice
somehow or had an extra put on some error path. But I couldn't find
any flow that would do either of those things
Jason
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: KASAN: use-after-free Read in ib_uverbs_remove_one
2020-05-28 14:33 KASAN: use-after-free Read in ib_uverbs_remove_one syzbot
[not found] ` <20200529083126.15808-1-hdanton@sina.com>
@ 2020-05-30 0:13 ` Jason Gunthorpe
1 sibling, 0 replies; 3+ messages in thread
From: Jason Gunthorpe @ 2020-05-30 0:13 UTC (permalink / raw)
To: syzbot
Cc: dledford, leon, linux-kernel, linux-rdma, michal.kalderon,
syzkaller-bugs, yishaih
On Thu, May 28, 2020 at 07:33:16AM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: c11d28ab Add linux-next specific files for 20200522
> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12fc3e72100000
> kernel config: https://syzkaller.appspot.com/x/.config?x=3f6dbdea4159fb66
> dashboard link: https://syzkaller.appspot.com/bug?extid=478fd0d54412b8759e0d
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>
> Unfortunately, I don't have any reproducer for this crash yet.
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+478fd0d54412b8759e0d@syzkaller.appspotmail.com
>
> ==================================================================
> BUG: KASAN: use-after-free in ib_uverbs_remove_one+0x411/0x4e0 drivers/infiniband/core/uverbs_main.c:1210
> Read of size 4 at addr ffff888096324578 by task syz-executor.2/15847
>
> CPU: 1 PID: 15847 Comm: syz-executor.2 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:77 [inline]
> dump_stack+0x18f/0x20d lib/dump_stack.c:118
> print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
> __kasan_report mm/kasan/report.c:513 [inline]
> kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
> ib_uverbs_remove_one+0x411/0x4e0 drivers/infiniband/core/uverbs_main.c:1210
> remove_client_context+0xbe/0x110 drivers/infiniband/core/device.c:732
> disable_device+0x13b/0x230 drivers/infiniband/core/device.c:1278
> __ib_unregister_device+0x91/0x180 drivers/infiniband/core/device.c:1445
> ib_unregister_device_and_put+0x57/0x80 drivers/infiniband/core/device.c:1508
> nldev_dellink+0x20a/0x310 drivers/infiniband/core/nldev.c:1571
> rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
> rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
> rdma_nl_rcv+0x586/0x900 drivers/infiniband/core/netlink.c:259
> netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
> netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
> netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
> sock_sendmsg_nosec net/socket.c:652 [inline]
> sock_sendmsg+0xcf/0x120 net/socket.c:672
> ____sys_sendmsg+0x6e6/0x810 net/socket.c:2352
> ___sys_sendmsg+0x100/0x170 net/socket.c:2406
> __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
> do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
> entry_SYSCALL_64_after_hwframe+0x49/0xb3
> RIP: 0033:0x45ca29
> Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007fd6764d1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
> RAX: ffffffffffffffda RBX: 00000000004ffa00 RCX: 000000000045ca29
> RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003
> RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
> R13: 00000000000009af R14: 00000000004d61b0 R15: 00007fd6764d26d4
>
> Allocated by task 9061:
> save_stack+0x1b/0x40 mm/kasan/common.c:48
> set_track mm/kasan/common.c:56 [inline]
> __kasan_kmalloc mm/kasan/common.c:494 [inline]
> __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
> kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
> kmalloc include/linux/slab.h:555 [inline]
> kzalloc include/linux/slab.h:669 [inline]
> ib_uverbs_add_one+0x80/0x7c0 drivers/infiniband/core/uverbs_main.c:1107
> add_client_context+0x400/0x5e0 drivers/infiniband/core/device.c:677
> enable_device_and_get+0x1cd/0x3b0 drivers/infiniband/core/device.c:1326
> ib_register_device drivers/infiniband/core/device.c:1392 [inline]
> ib_register_device+0xa12/0xda0 drivers/infiniband/core/device.c:1353
> siw_device_register drivers/infiniband/sw/siw/siw_main.c:70 [inline]
> siw_newlink drivers/infiniband/sw/siw/siw_main.c:565 [inline]
> siw_newlink+0xd37/0x1240 drivers/infiniband/sw/siw/siw_main.c:542
> nldev_newlink+0x29e/0x420 drivers/infiniband/core/nldev.c:1541
> rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
> rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
> rdma_nl_rcv+0x586/0x900 drivers/infiniband/core/netlink.c:259
> netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
> netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
> netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
> sock_sendmsg_nosec net/socket.c:652 [inline]
> sock_sendmsg+0xcf/0x120 net/socket.c:672
> ____sys_sendmsg+0x6e6/0x810 net/socket.c:2352
> ___sys_sendmsg+0x100/0x170 net/socket.c:2406
> __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
> do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
> entry_SYSCALL_64_after_hwframe+0x49/0xb3
>
> Freed by task 15847:
> save_stack+0x1b/0x40 mm/kasan/common.c:48
> set_track mm/kasan/common.c:56 [inline]
> kasan_set_free_info mm/kasan/common.c:316 [inline]
> __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
> __cache_free mm/slab.c:3426 [inline]
> kfree+0x109/0x2b0 mm/slab.c:3757
> device_release+0x71/0x200 drivers/base/core.c:1541
> kobject_cleanup lib/kobject.c:701 [inline]
> kobject_release lib/kobject.c:732 [inline]
> kref_put include/linux/kref.h:65 [inline]
> kobject_put+0x1c8/0x2f0 lib/kobject.c:749
> cdev_device_del+0x69/0x80 fs/char_dev.c:575
> ib_uverbs_remove_one+0x31/0x4e0 drivers/infiniband/core/uverbs_main.c:1209
I still can't figure out how this is possible, but I can say
cdev_device_del should not be freeing this memory - it can only mean
the uverbs_dev->dev.kref has become put several more times than it
should have.
Hopefully syzkaller will hit a refcount underflow and tell us where as
I checked every put_device obviously connected to uverbs_dev and found
nothing..
Jason
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-05-30 0:13 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2020-05-28 14:33 KASAN: use-after-free Read in ib_uverbs_remove_one syzbot
[not found] ` <20200529083126.15808-1-hdanton@sina.com>
2020-05-29 13:09 ` Jason Gunthorpe
2020-05-30 0:13 ` Jason Gunthorpe
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