general protection fault in bdev_read_page (2)

From: syzbot
Date: Sun Jul 05 2020 - 15:12:22 EST


Hello,

syzbot found the following crash on:

HEAD commit: 7c30b859 Merge tag 'spi-fix-v5.8-rc3' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1279b86b100000
kernel config: https://syzkaller.appspot.com/x/.config?x=7be693511b29b338
dashboard link: https://syzkaller.appspot.com/bug?extid=662448179365dddc1880
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13bd80a3100000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16af525b100000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+662448179365dddc1880@xxxxxxxxxxxxxxxxxxxxxxxxx

general protection fault, probably for non-canonical address 0xdffffc000000001e: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000f0-0x00000000000000f7]
CPU: 0 PID: 7121 Comm: systemd-udevd Not tainted 5.8.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bdev_read_page+0x35/0x290 fs/block_dev.c:700
Code: f5 53 48 89 fb 48 83 ec 08 48 89 14 24 e8 03 12 a5 ff 48 8d bb f0 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e7 01 00 00 4c 8b bb f0 00 00 00 48 b8 00 00 00
RSP: 0018:ffffc90001b57530 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81cf749a
RDX: 000000000000001e RSI: ffffffff81cea51d RDI: 00000000000000f0
RBP: fff89719b6b00000 R08: 0000000000000001 R09: ffffea0002871787
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffc90001b57748
FS: 00007fde67d458c0(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f65ed31138 CR3: 00000000a78d8000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_mpage_readpage+0x10ca/0x1ef0 fs/mpage.c:302
mpage_readahead+0x3a2/0x870 fs/mpage.c:391
read_pages+0x1df/0x8d0 mm/readahead.c:130
page_cache_readahead_unbounded+0x572/0x850 mm/readahead.c:244
__do_page_cache_readahead mm/readahead.c:273 [inline]
force_page_cache_readahead+0x2e9/0x460 mm/readahead.c:303
page_cache_sync_readahead mm/readahead.c:580 [inline]
page_cache_sync_readahead+0x113/0x130 mm/readahead.c:567
generic_file_buffered_read+0x108c/0x27e0 mm/filemap.c:2033
generic_file_read_iter+0x396/0x4e0 mm/filemap.c:2307
blkdev_read_iter+0x11b/0x180 fs/block_dev.c:2044
call_read_iter include/linux/fs.h:1901 [inline]
new_sync_read+0x41a/0x6e0 fs/read_write.c:415
__vfs_read+0xc9/0x100 fs/read_write.c:428
vfs_read+0x1f6/0x420 fs/read_write.c:462
ksys_read+0x12d/0x250 fs/read_write.c:588
do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fde66e8c210
Code: Bad RIP value.
RSP: 002b:00007fff13285fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 000055f65ed30d00 RCX: 00007fde66e8c210
RDX: 0000000000000400 RSI: 000055f65ed30d28 RDI: 000000000000000f
RBP: 000055f65ed34e80 R08: 00007fde66e76f88 R09: 0000000000000430
R10: 000000000000006d R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000400 R14: 000055f65ed34ed0 R15: 0000000000000400
Modules linked in:
---[ end trace 5b6f53a9af7ced6f ]---
RIP: 0010:bdev_read_page+0x35/0x290 fs/block_dev.c:700
Code: f5 53 48 89 fb 48 83 ec 08 48 89 14 24 e8 03 12 a5 ff 48 8d bb f0 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e7 01 00 00 4c 8b bb f0 00 00 00 48 b8 00 00 00
RSP: 0018:ffffc90001b57530 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81cf749a
RDX: 000000000000001e RSI: ffffffff81cea51d RDI: 00000000000000f0
RBP: fff89719b6b00000 R08: 0000000000000001 R09: ffffea0002871787
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffc90001b57748
FS: 00007fde67d458c0(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5807cc2ab4 CR3: 00000000a78d8000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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