TITLE: KASAN: wild-memory-access Read in sg_read
ALT: bad-access in sg_read
TYPE: KASAN-READ

[   67.633749] ==================================================================
[   67.633767] BUG: KASAN: wild-memory-access in sg_read+0xe5c/0x1440
[   67.633774] Read of size 4096 at addr ffe70873f7f2b000 by task syz-executor1/13133
[   67.633775] 
[   67.633796] CPU: 0 PID: 13133 Comm: syz-executor1 Not tainted 4.9.80-g550c01d #29
[   67.633801] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   67.633815]  ffff8801b42afa38 ffffffff81d94b69 ffe70873f7f2b000 0000000000001000
[   67.633827]  0000000000000000 0000000000000000 ffff8801c5ef4340 ffff8801b42afa80
[   67.633838]  ffffffff8153e49e ffffffff8266a72c 0000000000000282 b11e0ea3aa111a19
[   67.633841] Call Trace:
[   67.633851]  [<ffffffff81d94b69>] dump_stack+0xc1/0x128
[   67.633860]  [<ffffffff8153e49e>] kasan_report+0x15e/0x360
[   67.633867]  [<ffffffff8266a72c>] ? sg_read+0xe5c/0x1440
[   67.633875]  [<ffffffff8153cfc7>] check_memory_region+0x137/0x190
[   67.633882]  [<ffffffff8153d031>] kasan_check_read+0x11/0x20
[   27.258999] ==================================================================
[   27.260623] kasan: CONFIG_KASAN_INLINE enabled
[   27.260630] kasan: GPF could be caused by NULL-ptr deref or user memory access
[   27.260634] general protection fault: 0000 [#1] PREEMPT SMP KASAN
[   27.260638] Dumping ftrace buffer:
[   27.260641]    (ftrace buffer empty)
[   27.260644] Modules linked in:
[   27.260651] CPU: 1 PID: 3377 Comm: syzkaller685434 Not tainted 4.4.107-g610c835 #4
[   27.260654] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   27.260658] task: ffff8800b823c740 task.stack: ffff8801d94c8000
[   27.260671] RIP: 0010:[<ffffffff8123487f>]  [<ffffffff8123487f>] __lock_acquire+0x61f/0x4b50
[   27.260675] RSP: 0018:ffff8801d94cf880  EFLAGS: 00010086
[   27.260678] RAX: dffffc0000000000 RBX: dead4ead00000000 RCX: ffffffff81237ade
[   27.260682] RDX: 1ffff1003a313890 RSI: 0000000000000008 RDI: ffff8801d189c480
[   27.260685] RBP: ffff8801d94cfa20 R08: 0000000000000001 R09: 0000000000000001
[   27.260688] R10: 0000000000000001 R11: 1ffff1003b299f22 R12: 0000000000000000
[   27.260692] R13: ffff8800b823c740 R14: ffff8801d189c478 R15: 0000000000000000
[   27.260697] FS:  0000000000000000(0000) GS:ffff8801db300000(0063) knlGS:00000000f47d3b40
[   27.260701] CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
[   27.260704] CR2: 00000000206f6000 CR3: 00000001d0a15000 CR4: 00000000001406e0
[   27.260713] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   27.260717] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   27.260718] Stack:
[   27.260725]  ffff8801d0ee0818 ffff8800b4b59d90 ffff8801d94cfa00 ffffffff8149e232
[   27.260733]  ffff8801d94cf8b0 ffffffff00000000 ffff8800b823c740 ffff8800b823cfb0
[   27.260739]  0000000000000288 ffff8800b823c740 0000000000000002 0000000000000002
[   27.260741] Call Trace:
[   27.260751]  [<ffffffff8149e232>] ? handle_mm_fault+0x3f2/0x3190
[   27.260758]  [<ffffffff81234260>] ? debug_check_no_locks_freed+0x2c0/0x2c0
[   27.260764]  [<ffffffff8148979e>] ? vmacache_update+0xfe/0x130
[   27.260772]  [<ffffffff810db470>] ? __do_page_fault+0x380/0xa00
[   27.260778]  [<ffffffff8123a61e>] lock_acquire+0x15e/0x460
[   27.260787]  [<ffffffff825b8a89>] ? sg_remove_request+0x69/0x110
[   27.260794]  [<ffffffff83773a1e>] _raw_write_lock_irqsave+0x4e/0x70
[   27.260800]  [<ffffffff825b8a89>] ? sg_remove_request+0x69/0x110
[   27.260806]  [<ffffffff825b8a89>] sg_remove_request+0x69/0x110
[   27.260813]  [<ffffffff825b9095>] sg_finish_rem_req+0x295/0x340
[   27.260819]  [<ffffffff825baed1>] sg_read+0xa21/0x1490
[   67.633888]  [<ffffffff8266a72c>] sg_read+0xe5c/0x1440
[   67.633896]  [<ffffffff826698d0>] ? sg_proc_seq_show_debug+0xd90/0xd90
[   67.633902]  [<ffffffff81644640>] ? fsnotify+0xf30/0xf30
[   67.633910]  [<ffffffff81bdc219>] ? avc_policy_seqno+0x9/0x20
[   67.633919]  [<ffffffff8156cc21>] do_loop_readv_writev.part.17+0x141/0x1e0
[   67.633926]  [<ffffffff81bd32d9>] ? security_file_permission+0x89/0x1e0
[   67.633933]  [<ffffffff826698d0>] ? sg_proc_seq_show_debug+0xd90/0xd90
[   67.633940]  [<ffffffff826698d0>] ? sg_proc_seq_show_debug+0xd90/0xd90
[   67.633947]  [<ffffffff81570a90>] do_readv_writev+0x520/0x750
[   67.633954]  [<ffffffff81570570>] ? vfs_write+0x530/0x530
[   67.633962]  [<ffffffff8136b494>] ? kcov_ioctl+0x24/0x1c0
[   67.633972]  [<ffffffff81dfbfab>] ? check_preemption_disabled+0x3b/0x200
[   67.633979]  [<ffffffff815d1581>] ? __fget+0x201/0x3a0
[   67.633986]  [<ffffffff815d15a8>] ? __fget+0x228/0x3a0
[   67.633992]  [<ffffffff815d13c7>] ? __fget+0x47/0x3a0
[   67.634000]  [<ffffffff81570d44>] vfs_readv+0x84/0xc0
[   67.634007]  [<ffffffff81570e66>] do_readv+0xe6/0x250
[   67.634014]  [<ffffffff81570d80>] ? vfs_readv+0xc0/0xc0
[   67.634022]  [<ffffffff838b344a>] ? entry_SYSCALL_64_fastpath+0x5/0xe8
[   67.634032]  [<ffffffff8123b64b>] ? trace_hardirqs_on_caller+0x38b/0x590
[   67.634040]  [<ffffffff81574357>] SyS_readv+0x27/0x30
[   67.634047]  [<ffffffff838b346e>] entry_SYSCALL_64_fastpath+0x29/0xe8
[   67.634050] ==================================================================
