fs/xattr.c:setxattr(): improve handling of allocation failures

This allocation can be as large as 64k.

 - Add __GFP_NOWARN so the a falied kmalloc() is silent

 - Fall back to vmalloc() if the kmalloc() failed

Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: David Rientjes <rientjes@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andrew Morton 2012-04-05 14:25:07 -07:00 committed by Linus Torvalds
parent 0d08d7b7e1
commit 44c824982f

View File

@ -321,6 +321,7 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
{
int error;
void *kvalue = NULL;
void *vvalue = NULL; /* If non-NULL, we used vmalloc() */
char kname[XATTR_NAME_MAX + 1];
if (flags & ~(XATTR_CREATE|XATTR_REPLACE))
@ -335,13 +336,25 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
if (size) {
if (size > XATTR_SIZE_MAX)
return -E2BIG;
kvalue = memdup_user(value, size);
if (IS_ERR(kvalue))
return PTR_ERR(kvalue);
kvalue = kmalloc(size, GFP_KERNEL | __GFP_NOWARN);
if (!kvalue) {
vvalue = vmalloc(size);
if (!vvalue)
return -ENOMEM;
kvalue = vvalue;
}
if (copy_from_user(kvalue, value, size)) {
error = -EFAULT;
goto out;
}
}
error = vfs_setxattr(d, kname, kvalue, size, flags);
kfree(kvalue);
out:
if (vvalue)
vfree(vvalue);
else
kfree(kvalue);
return error;
}