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

This allocation can be as large as 64k.

 - Add __GFP_NOWARN so the falied kmalloc() is silent

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

Signed-off-by: Sasha Levin <levinsasha928@gmail.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:
Sasha Levin 2012-07-30 14:39:13 -07:00 committed by Linus Torvalds
parent 32b4560b04
commit 779302e678

View file

@ -427,6 +427,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
{
ssize_t error;
void *kvalue = NULL;
void *vvalue = NULL;
char kname[XATTR_NAME_MAX + 1];
error = strncpy_from_user(kname, name, sizeof(kname));
@ -438,9 +439,13 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
if (size) {
if (size > XATTR_SIZE_MAX)
size = XATTR_SIZE_MAX;
kvalue = kzalloc(size, GFP_KERNEL);
if (!kvalue)
return -ENOMEM;
kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
if (!kvalue) {
vvalue = vmalloc(size);
if (!vvalue)
return -ENOMEM;
kvalue = vvalue;
}
}
error = vfs_getxattr(d, kname, kvalue, size);
@ -452,7 +457,10 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
than XATTR_SIZE_MAX bytes. Not possible. */
error = -E2BIG;
}
kfree(kvalue);
if (vvalue)
vfree(vvalue);
else
kfree(kvalue);
return error;
}