[PATCH] selinux: Add __GFP_NOWARN to allocation at str_read()

syzbot is hitting warning at str_read() [1] because len parameter can become larger than KMALLOC_MAX_SIZE. We don't need to emit warning for this case. [1] https://syzkaller.appspot.com/bug?id=7f2f5aad79ea8663c296a2eedb81978401a908f0 Signed-off-by: Tetsuo Handa Reported-by: syzbot ---

WARNING: kmalloc bug in str_read

Hello, syzbot found the following crash on: HEAD commit:ca16eb342ebe Merge tag 'for-linus-20180906' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14cad42140 kernel config: https://syzkaller.appspot.com/x/.config?x=6c9564cd177daf0c