[syzbot] UBSAN: shift-out-of-bounds in do_mpage_readpage

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    d2b6f8a1 Merge tag 'xfs-5.13-merge-3' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11dfac0dd00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d360b81e47df40ea
dashboard link: https://syzkaller.appspot.com/bug?extid=cf89d662483d6a1a0790
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17051fc3d00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=163ab395d00000

The issue was bisected to:

commit dcd479e10a0510522a5d88b29b8f79ea3467d501
Author: Johannes Berg <johannes.berg@xxxxxxxxx>
Date:   Fri Oct 9 12:17:11 2020 +0000

    mac80211: always wind down STA state

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=10795f2dd00000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=12795f2dd00000
console output: https://syzkaller.appspot.com/x/log.txt?x=14795f2dd00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cf89d662483d6a1a0790@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: dcd479e10a05 ("mac80211: always wind down STA state")

================================================================================
UBSAN: shift-out-of-bounds in fs/mpage.c:189:40
shift exponent 4294967279 is too large for 64-bit type 'long long unsigned int'
CPU: 1 PID: 8457 Comm: systemd-udevd Not tainted 5.12.0-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
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327
 do_mpage_readpage.cold+0x226/0x2bb fs/mpage.c:189
 mpage_readahead+0x3a3/0x880 fs/mpage.c:389
 read_pages+0x1df/0x8d0 mm/readahead.c:130
 page_cache_ra_unbounded+0x61f/0x920 mm/readahead.c:238
 do_page_cache_ra mm/readahead.c:267 [inline]
 force_page_cache_ra+0x3ba/0x5b0 mm/readahead.c:299
 page_cache_sync_ra+0x107/0x200 mm/readahead.c:573
 page_cache_sync_readahead include/linux/pagemap.h:864 [inline]
 filemap_get_pages+0x29f/0x1920 mm/filemap.c:2442
 filemap_read+0x2ca/0xe40 mm/filemap.c:2525
 generic_file_read_iter+0x397/0x4f0 mm/filemap.c:2676
 blkdev_read_iter+0x11b/0x180 fs/block_dev.c:1720
 call_read_iter include/linux/fs.h:2110 [inline]
 new_sync_read+0x41e/0x6e0 fs/read_write.c:415
 vfs_read+0x35c/0x570 fs/read_write.c:496
 ksys_read+0x12d/0x250 fs/read_write.c:634
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fdc7280d210
Code: 73 01 c3 48 8b 0d 98 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d b9 c1 20 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 4e fc ff ff 48 89 04 24
RSP: 002


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