f2fs: make posix_acl_create() safer and cleaner

Our f2fs_acl_create is copied from posix_acl_create in ./fs/posix_acl.c and
modified to avoid deadlock bug when inline_dentry feature is enabled.

Dan Carpenter rewrites posix_acl_create in commit 2799563b281f
("fs/posix_acl.c: make posix_acl_create() safer and cleaner") to make this
function more safer, so that we can avoid potential bug in its caller,
especially for ocfs2.

Let's back port the patch to f2fs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu 2015-04-18 18:03:58 +08:00 committed by Jaegeuk Kim
parent 5d79988139
commit 272e083f7a

View File

@ -334,51 +334,45 @@ static int f2fs_acl_create(struct inode *dir, umode_t *mode,
struct page *dpage)
{
struct posix_acl *p;
struct posix_acl *clone;
int ret;
*acl = NULL;
*default_acl = NULL;
if (S_ISLNK(*mode) || !IS_POSIXACL(dir))
goto no_acl;
return 0;
p = __f2fs_get_acl(dir, ACL_TYPE_DEFAULT, dpage);
if (IS_ERR(p)) {
if (p == ERR_PTR(-EOPNOTSUPP))
goto apply_umask;
return PTR_ERR(p);
if (!p || p == ERR_PTR(-EOPNOTSUPP)) {
*mode &= ~current_umask();
return 0;
}
if (IS_ERR(p))
return PTR_ERR(p);
if (!p)
goto apply_umask;
*acl = f2fs_acl_clone(p, GFP_NOFS);
if (!*acl)
clone = f2fs_acl_clone(p, GFP_NOFS);
if (!clone)
goto no_mem;
ret = f2fs_acl_create_masq(*acl, mode);
ret = f2fs_acl_create_masq(clone, mode);
if (ret < 0)
goto no_mem_clone;
if (ret == 0) {
posix_acl_release(*acl);
*acl = NULL;
}
if (ret == 0)
posix_acl_release(clone);
else
*acl = clone;
if (!S_ISDIR(*mode)) {
if (!S_ISDIR(*mode))
posix_acl_release(p);
*default_acl = NULL;
} else {
else
*default_acl = p;
}
return 0;
apply_umask:
*mode &= ~current_umask();
no_acl:
*default_acl = NULL;
*acl = NULL;
return 0;
no_mem_clone:
posix_acl_release(*acl);
posix_acl_release(clone);
no_mem:
posix_acl_release(p);
return -ENOMEM;