syzbot


KASAN: use-after-free Read in rdma_resolve_addr

Status: fixed on 2019/02/21 08:43
Subsystems: rdma
[Documentation on labels]
Reported-by: syzbot+5013f86be1187ccf3800@syzkaller.appspotmail.com
Fix commit: 5fe23f262e05 ucma: fix a use-after-free in ucma_resolve_ip()
First crash: 2032d, last: 2032d
Discussions (1)
Title Replies (including bot) Last reply
KASAN: use-after-free Read in rdma_resolve_addr 1 (2) 2019/02/20 15:21

Sample crash report:
binder: 12750:12764 transaction failed 29201/-71, size 0-8 line 2762
audit: type=1326 audit(1537939130.796:20382): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=228 compat=0 ip=0x45a3da code=0x50000
==================================================================
BUG: KASAN: use-after-free in rdma_resolve_addr+0x1e97/0x2730 drivers/infiniband/core/cma.c:2981
Read of size 2 at addr ffff88018529b1e0 by task syz-executor2/12772

CPU: 1 PID: 12772 Comm: syz-executor2 Not tainted 4.19.0-rc5+ #254
audit: type=1326 audit(1537939130.846:20383): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x457579 code=0x50000
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+0x1c4/0x2b4 lib/dump_stack.c:113
 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:431
 rdma_resolve_addr+0x1e97/0x2730 drivers/infiniband/core/cma.c:2981
audit: type=1326 audit(1537939130.846:20384): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=228 compat=0 ip=0x45a3da code=0x50000
 ucma_resolve_ip+0x242/0x2a0 drivers/infiniband/core/ucma.c:713
 ucma_write+0x336/0x420 drivers/infiniband/core/ucma.c:1686
audit: type=1326 audit(1537939130.866:20385): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=298 compat=0 ip=0x457579 code=0x50000
 __vfs_write+0x119/0x9f0 fs/read_write.c:485
audit: type=1326 audit(1537939130.866:20386): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=228 compat=0 ip=0x45a3da code=0x50000
 vfs_write+0x1fc/0x560 fs/read_write.c:549
 ksys_write+0x101/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
audit: type=1326 audit(1537939130.876:20387): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x457579 code=0x50000
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d b4 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
audit: type=1326 audit(1537939130.876:20388): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x457579 code=0x50000
RSP: 002b:00007f451b87cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000048 RSI: 0000000020000240 RDI: 0000000000000009
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f451b87d6d4
R13: 00000000004cb6a0 R14: 00000000004d8cb8 R15: 00000000ffffffff

binder: BINDER_SET_CONTEXT_MGR already set
Allocated by task 12777:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620
 kmalloc include/linux/slab.h:513 [inline]
 kzalloc include/linux/slab.h:707 [inline]
 __rdma_create_id+0xdf/0x790 drivers/infiniband/core/cma.c:784
 ucma_create_id+0x39b/0x990 drivers/infiniband/core/ucma.c:504
binder: 12750:12773 ioctl 40046207 0 returned -16
 ucma_write+0x336/0x420 drivers/infiniband/core/ucma.c:1686
 __vfs_write+0x119/0x9f0 fs/read_write.c:485
 vfs_write+0x1fc/0x560 fs/read_write.c:549
 ksys_write+0x101/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

audit: type=1326 audit(1537939130.886:20389): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x457579 code=0x50000
Freed by task 12770:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3813
 rdma_destroy_id+0x835/0xcc0 drivers/infiniband/core/cma.c:1739
 ucma_close+0x100/0x300 drivers/infiniband/core/ucma.c:1765
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
audit: type=1326 audit(1537939130.926:20390): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x457579 code=0x50000
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

audit: type=1326 audit(1537939130.926:20391): auid=4294967295 uid=0 gid=0 ses=4294967295 subj==unconfined pid=12758 comm="syz-executor4" exe="/root/syz-executor4" sig=0 arch=c000003e syscall=202 compat=0 ip=0x457579 code=0x50000
The buggy address belongs to the object at ffff88018529b1c0
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 32 bytes inside of
 2048-byte region [ffff88018529b1c0, ffff88018529b9c0)
The buggy address belongs to the page:
page:ffffea000614a680 count:1 mapcount:0 mapping:ffff8801da800c40 index:0xffff88018529a940
binder: 12750:12764 ERROR: BC_REGISTER_LOOPER called without request
 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffffea00061c4188 ffffea000632af08 ffff8801da800c40
raw: ffff88018529a940 ffff88018529a0c0 0000000100000002 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88018529b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88018529b100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88018529b180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                       ^
 ffff88018529b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88018529b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
kobject: 'loop5' (000000002cf6e86e): kobject_uevent_env

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/09/26 05:19 upstream 846e8dd47c26 b7e11289 .config console log report ci-upstream-kasan-gce
* Struck through repros no longer work on HEAD.