From: Arve Hjønnevåg <arve@android.com>
Date: Thu, 11 Mar 2010 00:38:33 +0000 (-0800)
Subject: Merge commit 'v2.6.32.9' into android-2.6.32
X-Git-Tag: firefly_0821_release~11625
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=67078ecae3edb5b4657dcb9f67f744ecccd18a97;p=firefly-linux-kernel-4.4.55.git

Merge commit 'v2.6.32.9' into android-2.6.32
---

67078ecae3edb5b4657dcb9f67f744ecccd18a97
diff --cc kernel/futex.c
index 546e13300d3b,1ad4fa6db725..c6a80616fcfd
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@@ -248,39 -245,8 +246,39 @@@ get_futex_key(u32 __user *uaddr, int fs
  		return 0;
  	}
  
 +	/*
 +	 * The futex is hashed differently depending on whether
 +	 * it's in a shared or private mapping.  So check vma first.
 +	 */
 +	vma = find_extend_vma(mm, address);
 +	if (unlikely(!vma))
 +		return -EFAULT;
 +
 +	/*
 +	 * Permissions.
 +	 */
 +	if (unlikely((vma->vm_flags & (VM_IO|VM_READ)) != VM_READ))
 +		return (vma->vm_flags & VM_IO) ? -EPERM : -EACCES;
 +
 +	/*
 +	 * Private mappings are handled in a simple way.
 +	 *
 +	 * NOTE: When userspace waits on a MAP_SHARED mapping, even if
 +	 * it's a read-only handle, it's expected that futexes attach to
 +	 * the object not the particular process.  Therefore we use
 +	 * VM_MAYSHARE here, not VM_SHARED which is restricted to shared
 +	 * mappings of _writable_ handles.
 +	 */
 +	if (likely(!(vma->vm_flags & VM_MAYSHARE))) {
 +		key->both.offset |= FUT_OFF_MMSHARED; /* reference taken on mm */
 +		key->private.mm = mm;
 +		key->private.address = address;
 +		get_futex_key_refs(key);
 +		return 0;
 +	}
 +
  again:
- 	err = get_user_pages_fast(address, 1, rw == VERIFY_WRITE, &page);
+ 	err = get_user_pages_fast(address, 1, 1, &page);
  	if (err < 0)
  		return err;