[PATCH 1/2] xfs: fix memory allocation failures with ACLs

Dave Chinner
2013-09-02T10:53:08Z

From: Dave Chinner <dchinner@redhat.com>

Ever since increasing the number of supported ACLs from 25 to as
many as can fit in an xattr, there have been reports of order 4
memory allocations failing in the ACL code. Fix it in the same way
we've fixed all the xattr read/write code that has the same problem.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_acl.c | 32 ++++++++++++++++++++++----------
1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
index 6951896..4ea73cc 100644
--- a/fs/xfs/xfs_acl.c
+++ b/fs/xfs/xfs_acl.c
@@ -152,9 +152,12 @@ xfs_get_acl(struct inode *inode, int type)
* go out to the disk.
*/
len = XFS_ACL_MAX_SIZE(ip->i_mount);
- xfs_acl = kzalloc(len, GFP_KERNEL);
- if (!xfs_acl)
- return ERR_PTR(-ENOMEM);
+ xfs_acl = kmem_zalloc(len, KM_SLEEP | KM_MAYFAIL);
+ if (!xfs_acl) {
+ xfs_acl = kmem_zalloc_large(len);
+ if (!xfs_acl)
+ return ERR_PTR(-ENOMEM);
+ }

error = -xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
&len, ATTR_ROOT);
@@ -175,10 +178,13 @@ xfs_get_acl(struct inode *inode, int type)
if (IS_ERR(acl))
goto out;

- out_update_cache:
+out_update_cache:
set_cached_acl(inode, type, acl);
- out:
- kfree(xfs_acl);
+out:
+ if (is_vmalloc_addr(xfs_acl))
+ kmem_free_large(xfs_acl);
+ else
+ kfree(xfs_acl);
return acl;
}

@@ -209,9 +215,12 @@ xfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
struct xfs_acl *xfs_acl;
int len = XFS_ACL_MAX_SIZE(ip->i_mount);

- xfs_acl = kzalloc(len, GFP_KERNEL);
- if (!xfs_acl)
- return -ENOMEM;
+ xfs_acl = kmem_zalloc(len, KM_SLEEP | KM_MAYFAIL);
+ if (!xfs_acl) {
+ xfs_acl = kmem_zalloc_large(len);
+ if (!xfs_acl)
+ return -ENOMEM;
+ }

xfs_acl_to_disk(xfs_acl, acl);

@@ -222,7 +231,10 @@ xfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
error = -xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
len, ATTR_ROOT);

- kfree(xfs_acl);
+ if (is_vmalloc_addr(xfs_acl))
+ kmem_free_large(xfs_acl);
+ else
+ kfree(xfs_acl);
} else {
/*
* A NULL ACL argument means we want to remove the ACL.
--
1.8.3.2