* [PATCH] Extended attribute fixes, etc.
@ 2003-02-11 19:18 Andreas Gruenbacher
2003-02-11 20:32 ` Andrew Morton
2003-02-15 11:07 ` Christoph Hellwig
0 siblings, 2 replies; 9+ messages in thread
From: Andreas Gruenbacher @ 2003-02-11 19:18 UTC (permalink / raw)
To: Andrew Morton; +Cc: linux-kernel, Theodore T'so
[-- Attachment #1: Type: text/plain, Size: 1119 bytes --]
Hi Andrew,
here are five patches against 2.5.60. Each file contains a brief
description of what it does.
The first two fix an [un]lock_kernel() bug, and an iops->listxattr() bug
that for some reason hasn't found its way into 2.5 yet. (Both bugs do
not exist in the current 2.4.19/2.4.20 patches at acl.bestbits.at).
The third to fifth are all steps towards trusted extended attributes,
which are useful for privileged processes (mostly daemons). One use for
this is Hierarchical Storage Management, in which a user space daemon
stores online/offline information for files in trusted EA's, and the
kernel communicates requests to bring files online to that daemon. This
class of EA's will also find its way into XFS and ReiserFS, and
expectedly also into JFS in this form. (Trusted EAs are included in the
2.4.19/2.4.20 patches as well.)
The intended patch order is:
kernel_lock_bug.diff
ext2_ext3_listxattr-bug.diff
xattr-flags.diff
xattr-flags-policy.diff
xattr-trusted.diff
Could you please feed the patches to Linus?
Thank you very much,
Andreas Gruenbacher.
[-- Attachment #2: ext2_ext3_listxattr-bug.diff --]
[-- Type: text/x-diff, Size: 4816 bytes --]
This patch fixes a bug in the ext2 and ext3 listxattr operation: Even if
an attribute is hidden from the user, the terminating NULL character was
included in the listxattr result. After the patch this doesn't happen
anymore.
Index: linux-2.5.60/fs/ext2/acl.c
--- linux-2.5.60~ext2_ext3_listxattr-bug/fs/ext2/acl.c 2003-02-11 12:30:30.000000000 +0100
+++ linux-2.5.60/fs/ext2/acl.c 2003-02-11 12:40:11.000000000 +0100
@@ -421,26 +421,26 @@
ext2_xattr_list_acl_access(char *list, struct inode *inode,
const char *name, int name_len)
{
- const size_t len = sizeof(XATTR_NAME_ACL_ACCESS)-1;
+ const size_t size = sizeof(XATTR_NAME_ACL_ACCESS);
if (!test_opt(inode->i_sb, POSIX_ACL))
return 0;
if (list)
- memcpy(list, XATTR_NAME_ACL_ACCESS, len);
- return len;
+ memcpy(list, XATTR_NAME_ACL_ACCESS, size);
+ return size;
}
static size_t
ext2_xattr_list_acl_default(char *list, struct inode *inode,
const char *name, int name_len)
{
- const size_t len = sizeof(XATTR_NAME_ACL_DEFAULT)-1;
+ const size_t size = sizeof(XATTR_NAME_ACL_DEFAULT);
if (!test_opt(inode->i_sb, POSIX_ACL))
return 0;
if (list)
- memcpy(list, XATTR_NAME_ACL_DEFAULT, len);
- return len;
+ memcpy(list, XATTR_NAME_ACL_DEFAULT, size);
+ return size;
}
static int
Index: linux-2.5.60/fs/ext2/xattr.c
--- linux-2.5.60~ext2_ext3_listxattr-bug/fs/ext2/xattr.c 2003-02-11 12:30:30.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr.c 2003-02-11 12:40:11.000000000 +0100
@@ -409,10 +409,9 @@
goto bad_block;
handler = ext2_xattr_handler(entry->e_name_index);
- if (handler) {
+ if (handler)
size += handler->list(NULL, inode, entry->e_name,
- entry->e_name_len) + 1;
- }
+ entry->e_name_len);
}
if (ext2_xattr_cache_insert(bh))
@@ -433,11 +432,9 @@
struct ext2_xattr_handler *handler;
handler = ext2_xattr_handler(entry->e_name_index);
- if (handler) {
+ if (handler)
buf += handler->list(buf, inode, entry->e_name,
entry->e_name_len);
- *buf++ = '\0';
- }
}
error = size;
Index: linux-2.5.60/fs/ext2/xattr_user.c
--- linux-2.5.60~ext2_ext3_listxattr-bug/fs/ext2/xattr_user.c 2003-02-11 12:30:30.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr_user.c 2003-02-11 12:40:11.000000000 +0100
@@ -29,8 +29,9 @@
if (list) {
memcpy(list, XATTR_USER_PREFIX, prefix_len);
memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
}
- return prefix_len + name_len;
+ return prefix_len + name_len + 1;
}
static int
Index: linux-2.5.60/fs/ext3/acl.c
--- linux-2.5.60~ext2_ext3_listxattr-bug/fs/ext3/acl.c 2003-02-11 12:37:36.000000000 +0100
+++ linux-2.5.60/fs/ext3/acl.c 2003-02-11 12:40:11.000000000 +0100
@@ -434,26 +434,26 @@
ext3_xattr_list_acl_access(char *list, struct inode *inode,
const char *name, int name_len)
{
- const size_t len = sizeof(XATTR_NAME_ACL_ACCESS)-1;
+ const size_t size = sizeof(XATTR_NAME_ACL_ACCESS);
if (!test_opt(inode->i_sb, POSIX_ACL))
return 0;
if (list)
- memcpy(list, XATTR_NAME_ACL_ACCESS, len);
- return len;
+ memcpy(list, XATTR_NAME_ACL_ACCESS, size);
+ return size;
}
static size_t
ext3_xattr_list_acl_default(char *list, struct inode *inode,
const char *name, int name_len)
{
- const size_t len = sizeof(XATTR_NAME_ACL_DEFAULT)-1;
+ const size_t size = sizeof(XATTR_NAME_ACL_DEFAULT);
if (!test_opt(inode->i_sb, POSIX_ACL))
return 0;
if (list)
- memcpy(list, XATTR_NAME_ACL_DEFAULT, len);
- return len;
+ memcpy(list, XATTR_NAME_ACL_DEFAULT, size);
+ return size;
}
static int
Index: linux-2.5.60/fs/ext3/xattr.c
--- linux-2.5.60~ext2_ext3_listxattr-bug/fs/ext3/xattr.c 2003-02-11 12:33:45.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.c 2003-02-11 12:40:11.000000000 +0100
@@ -402,10 +402,9 @@
goto bad_block;
handler = ext3_xattr_handler(entry->e_name_index);
- if (handler) {
+ if (handler)
size += handler->list(NULL, inode, entry->e_name,
- entry->e_name_len) + 1;
- }
+ entry->e_name_len);
}
if (ext3_xattr_cache_insert(bh))
@@ -426,11 +425,9 @@
struct ext3_xattr_handler *handler;
handler = ext3_xattr_handler(entry->e_name_index);
- if (handler) {
+ if (handler)
buf += handler->list(buf, inode, entry->e_name,
entry->e_name_len);
- *buf++ = '\0';
- }
}
error = size;
Index: linux-2.5.60/fs/ext3/xattr_user.c
--- linux-2.5.60~ext2_ext3_listxattr-bug/fs/ext3/xattr_user.c 2003-02-11 12:38:02.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr_user.c 2003-02-11 12:40:11.000000000 +0100
@@ -31,8 +31,9 @@
if (list) {
memcpy(list, XATTR_USER_PREFIX, prefix_len);
memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
}
- return prefix_len + name_len;
+ return prefix_len + name_len + 1;
}
static int
[-- Attachment #3: kernel_lock_bug.diff --]
[-- Type: text/x-diff, Size: 5697 bytes --]
This patch fixes an unbalanced lock_kernel()/unlock_kernel() path in the
ext3 extended attributes code. Instead of fixing this in
fs/ext3/xattr_user.c, the locking code is modev to fs/ext3/xattr.c,
since most other types of extended attributes will need the exact same
functioanlity.
Andreas Gruenbacher <agruen@suse.de>
Index: linux-2.5.60/fs/ext3/xattr.c
--- linux-2.5.60~kernel_lock_bug/fs/ext3/xattr.c 2003-02-10 22:46:39.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.c 2003-02-11 12:33:45.000000000 +0100
@@ -88,8 +88,9 @@
# define ea_bdebug(f...)
#endif
-static int ext3_xattr_set2(handle_t *, struct inode *, struct buffer_head *,
- struct ext3_xattr_header *);
+static int ext3_xattr_set_handle2(handle_t *, struct inode *,
+ struct buffer_head *,
+ struct ext3_xattr_header *);
static int ext3_xattr_cache_insert(struct buffer_head *);
static struct buffer_head *ext3_xattr_cache_find(struct inode *,
@@ -459,7 +460,7 @@
}
/*
- * ext3_xattr_set()
+ * ext3_xattr_set_handle()
*
* Create, replace or remove an extended attribute for this inode. Buffer
* is NULL to remove an existing extended attribute, and non-NULL to
@@ -471,8 +472,9 @@
* Returns 0, or a negative error number on failure.
*/
int
-ext3_xattr_set(handle_t *handle, struct inode *inode, int name_index,
- const char *name, const void *value, size_t value_len, int flags)
+ext3_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
+ const char *name, const void *value, size_t value_len,
+ int flags)
{
struct super_block *sb = inode->i_sb;
struct buffer_head *bh = NULL;
@@ -673,7 +675,8 @@
/* Remove this attribute. */
if (EXT3_XATTR_NEXT(ENTRY(header+1)) == last) {
/* This block is now empty. */
- error = ext3_xattr_set2(handle, inode, bh,NULL);
+ error = ext3_xattr_set_handle2(handle, inode,
+ bh, NULL);
goto cleanup;
} else {
/* Remove the old name. */
@@ -701,7 +704,7 @@
}
ext3_xattr_rehash(header, here);
- error = ext3_xattr_set2(handle, inode, bh, header);
+ error = ext3_xattr_set_handle2(handle, inode, bh, header);
cleanup:
brelse(bh);
@@ -713,11 +716,12 @@
}
/*
- * Second half of ext3_xattr_set(): Update the file system.
+ * Second half of ext3_xattr_set_handle(): Update the file system.
*/
static int
-ext3_xattr_set2(handle_t *handle, struct inode *inode,
- struct buffer_head *old_bh, struct ext3_xattr_header *header)
+ext3_xattr_set_handle2(handle_t *handle, struct inode *inode,
+ struct buffer_head *old_bh,
+ struct ext3_xattr_header *header)
{
struct super_block *sb = inode->i_sb;
struct buffer_head *new_bh = NULL;
@@ -832,6 +836,34 @@
}
/*
+ * ext3_xattr_set()
+ *
+ * Like ext3_xattr_set_handle, but start from an inode. This extended
+ * attribute modification is a filesystem transaction by itself.
+ *
+ * Returns 0, or a negative error number on failure.
+ */
+int
+ext3_xattr_set(struct inode *inode, int name_index, const char *name,
+ const void *value, size_t value_len, int flags)
+{
+ handle_t *handle;
+ int error;
+
+ lock_kernel();
+ handle = ext3_journal_start(inode, EXT3_XATTR_TRANS_BLOCKS);
+ if (IS_ERR(handle))
+ error = PTR_ERR(handle);
+ else
+ error = ext3_xattr_set_handle(handle, inode, name_index, name,
+ value, value_len, flags);
+ ext3_journal_stop(handle, inode);
+ unlock_kernel();
+
+ return error;
+}
+
+/*
* ext3_xattr_delete_inode()
*
* Free extended attribute resources associated with this inode. This
Index: linux-2.5.60/fs/ext3/xattr.h
--- linux-2.5.60~kernel_lock_bug/fs/ext3/xattr.h 2003-02-10 22:46:39.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.h 2003-02-11 12:39:17.000000000 +0100
@@ -73,7 +73,8 @@
extern int ext3_xattr_get(struct inode *, int, const char *, void *, size_t);
extern int ext3_xattr_list(struct inode *, char *, size_t);
-extern int ext3_xattr_set(handle_t *handle, struct inode *, int, const char *, const void *, size_t, int);
+extern int ext3_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
+extern int ext3_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
extern void ext3_xattr_delete_inode(handle_t *, struct inode *);
extern void ext3_xattr_put_super(struct super_block *);
@@ -101,7 +102,14 @@
}
static inline int
-ext3_xattr_set(handle_t *handle, struct inode *inode, int name_index,
+ext3_xattr_set(struct inode *inode, int name_index, const char *name,
+ const void *value, size_t size, int flags)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int
+ext3_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
const char *name, const void *value, size_t size, int flags)
{
return -EOPNOTSUPP;
Index: linux-2.5.60/fs/ext3/xattr_user.c
--- linux-2.5.60~kernel_lock_bug/fs/ext3/xattr_user.c 2003-02-10 22:46:39.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr_user.c 2003-02-11 12:38:02.000000000 +0100
@@ -61,7 +61,6 @@
ext3_xattr_user_set(struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
- handle_t *handle;
int error;
if (strcmp(name, "") == 0)
@@ -79,16 +78,9 @@
if (error)
return error;
- lock_kernel();
- handle = ext3_journal_start(inode, EXT3_XATTR_TRANS_BLOCKS);
- if (IS_ERR(handle))
- return PTR_ERR(handle);
- error = ext3_xattr_set(handle, inode, EXT3_XATTR_INDEX_USER, name,
- value, size, flags);
- ext3_journal_stop(handle, inode);
- unlock_kernel();
+ return ext3_xattr_set(inode, EXT3_XATTR_INDEX_USER, name,
+ value, size, flags);
- return error;
}
struct ext3_xattr_handler ext3_xattr_user_handler = {
[-- Attachment #4: xattr-trusted.diff --]
[-- Type: text/x-diff, Size: 9404 bytes --]
This patch adds trusted extended attributes. Trusted extended
attributes are visible and accessible only to processes that have
the CAP_SYS_ADMIN capability. Attributes in this class are used to
implement mechanisms in user space (i.e., outside the kernel) which keep
information in extended attributes to which ordinary processes have no
access. HSM is an example.
Index: linux-2.5.60/fs/ext2/Makefile
--- linux-2.5.60~xattr-trusted/fs/ext2/Makefile 2003-02-11 12:29:38.000000000 +0100
+++ linux-2.5.60/fs/ext2/Makefile 2003-02-11 12:47:41.000000000 +0100
@@ -8,7 +8,7 @@
ioctl.o namei.o super.o symlink.o
ifeq ($(CONFIG_EXT2_FS_XATTR),y)
-ext2-objs += xattr.o xattr_user.o
+ext2-objs += xattr.o xattr_user.o xattr_trusted.o
endif
ifeq ($(CONFIG_EXT2_FS_POSIX_ACL),y)
Index: linux-2.5.60/fs/ext2/xattr.c
--- linux-2.5.60~xattr-trusted/fs/ext2/xattr.c 2003-02-11 12:40:20.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr.c 2003-02-11 12:47:41.000000000 +0100
@@ -1096,27 +1096,35 @@
{
int err;
- err = ext2_xattr_register(EXT2_XATTR_INDEX_USER, &ext2_xattr_user_handler);
+ err = ext2_xattr_register(EXT2_XATTR_INDEX_USER,
+ &ext2_xattr_user_handler);
if (err)
return err;
+ err = ext2_xattr_register(EXT2_XATTR_INDEX_TRUSTED,
+ &ext2_xattr_trusted_handler);
+ if (err)
+ goto out;
#ifdef CONFIG_EXT2_FS_POSIX_ACL
err = init_ext2_acl();
if (err)
- goto out;
+ goto out1;
#endif
ext2_xattr_cache = mb_cache_create("ext2_xattr", NULL,
sizeof(struct mb_cache_entry) +
sizeof(struct mb_cache_entry_index), 1, 6);
if (!ext2_xattr_cache) {
err = -ENOMEM;
- goto out1;
+ goto out2;
}
return 0;
-out1:
+out2:
#ifdef CONFIG_EXT2_FS_POSIX_ACL
exit_ext2_acl();
-out:
+out1:
#endif
+ ext2_xattr_unregister(EXT2_XATTR_INDEX_TRUSTED,
+ &ext2_xattr_trusted_handler);
+out:
ext2_xattr_unregister(EXT2_XATTR_INDEX_USER,
&ext2_xattr_user_handler);
return err;
@@ -1129,5 +1137,8 @@
#ifdef CONFIG_EXT2_FS_POSIX_ACL
exit_ext2_acl();
#endif
- ext2_xattr_unregister(EXT2_XATTR_INDEX_USER, &ext2_xattr_user_handler);
+ ext2_xattr_unregister(EXT2_XATTR_INDEX_TRUSTED,
+ &ext2_xattr_trusted_handler);
+ ext2_xattr_unregister(EXT2_XATTR_INDEX_USER,
+ &ext2_xattr_user_handler);
}
Index: linux-2.5.60/fs/ext2/xattr.h
--- linux-2.5.60~xattr-trusted/fs/ext2/xattr.h 2003-02-11 12:29:38.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr.h 2003-02-11 12:47:41.000000000 +0100
@@ -21,6 +21,7 @@
#define EXT2_XATTR_INDEX_USER 1
#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2
#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3
+#define EXT2_XATTR_INDEX_TRUSTED 4
struct ext2_xattr_header {
__u32 h_magic; /* magic number for identification */
@@ -132,4 +133,5 @@
# endif /* CONFIG_EXT2_FS_XATTR */
extern struct ext2_xattr_handler ext2_xattr_user_handler;
+extern struct ext2_xattr_handler ext2_xattr_trusted_handler;
Index: linux-2.5.60/fs/ext2/xattr_trusted.c
--- linux-2.5.60~xattr-trusted/fs/ext2/xattr_trusted.c 2003-02-11 12:47:41.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr_trusted.c 2003-02-11 12:47:41.000000000 +0100
@@ -0,0 +1,63 @@
+/*
+ * linux/fs/ext2/xattr_trusted.c
+ * Handler for trusted extended attributes.
+ *
+ * Copyright (C) 2003 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.h>
+#include <linux/ext2_fs.h>
+#include "xattr.h"
+
+#define XATTR_TRUSTED_PREFIX "trusted."
+
+static size_t
+ext2_xattr_trusted_list(char *list, struct inode *inode,
+ const char *name, int name_len, int flags)
+{
+ const int prefix_len = sizeof(XATTR_TRUSTED_PREFIX)-1;
+
+ if (!((flags & XATTR_KERNEL_CONTEXT) || capable(CAP_SYS_ADMIN)))
+ return 0;
+
+ if (list) {
+ memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
+ memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
+ }
+ return prefix_len + name_len + 1;
+}
+
+static int
+ext2_xattr_trusted_get(struct inode *inode, const char *name,
+ void *buffer, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ if (!((flags & XATTR_KERNEL_CONTEXT) || capable(CAP_SYS_ADMIN)))
+ return -EPERM;
+ return ext2_xattr_get(inode, EXT2_XATTR_INDEX_TRUSTED, name,
+ buffer, size);
+}
+
+static int
+ext2_xattr_trusted_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ if (!((flags & XATTR_KERNEL_CONTEXT) || capable(CAP_SYS_ADMIN)))
+ return -EPERM;
+ return ext2_xattr_set(inode, EXT2_XATTR_INDEX_TRUSTED, name,
+ value, size, flags);
+}
+
+struct ext2_xattr_handler ext2_xattr_trusted_handler = {
+ .prefix = XATTR_TRUSTED_PREFIX,
+ .list = ext2_xattr_trusted_list,
+ .get = ext2_xattr_trusted_get,
+ .set = ext2_xattr_trusted_set,
+};
Index: linux-2.5.60/fs/ext3/Makefile
--- linux-2.5.60~xattr-trusted/fs/ext3/Makefile 2003-02-11 12:29:38.000000000 +0100
+++ linux-2.5.60/fs/ext3/Makefile 2003-02-11 12:47:41.000000000 +0100
@@ -8,7 +8,7 @@
ioctl.o namei.o super.o symlink.o hash.o
ifeq ($(CONFIG_EXT3_FS_XATTR),y)
-ext3-objs += xattr.o xattr_user.o
+ext3-objs += xattr.o xattr_user.o xattr_trusted.o
endif
ifeq ($(CONFIG_EXT3_FS_POSIX_ACL),y)
Index: linux-2.5.60/fs/ext3/xattr.c
--- linux-2.5.60~xattr-trusted/fs/ext3/xattr.c 2003-02-11 12:40:20.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.c 2003-02-11 12:47:41.000000000 +0100
@@ -1133,27 +1133,35 @@
{
int err;
- err = ext3_xattr_register(EXT3_XATTR_INDEX_USER, &ext3_xattr_user_handler);
+ err = ext3_xattr_register(EXT3_XATTR_INDEX_USER,
+ &ext3_xattr_user_handler);
if (err)
return err;
+ err = ext3_xattr_register(EXT3_XATTR_INDEX_TRUSTED,
+ &ext3_xattr_trusted_handler);
+ if (err)
+ goto out;
#ifdef CONFIG_EXT3_FS_POSIX_ACL
err = init_ext3_acl();
if (err)
- goto out;
+ goto out1;
#endif
ext3_xattr_cache = mb_cache_create("ext3_xattr", NULL,
sizeof(struct mb_cache_entry) +
sizeof(struct mb_cache_entry_index), 1, 6);
if (!ext3_xattr_cache) {
err = -ENOMEM;
- goto out1;
+ goto out2;
}
return 0;
-out1:
+out2:
#ifdef CONFIG_EXT3_FS_POSIX_ACL
exit_ext3_acl();
-out:
+out1:
#endif
+ ext3_xattr_unregister(EXT3_XATTR_INDEX_TRUSTED,
+ &ext3_xattr_trusted_handler);
+out:
ext3_xattr_unregister(EXT3_XATTR_INDEX_USER,
&ext3_xattr_user_handler);
return err;
@@ -1168,5 +1176,8 @@
#ifdef CONFIG_EXT3_FS_POSIX_ACL
exit_ext3_acl();
#endif
- ext3_xattr_unregister(EXT3_XATTR_INDEX_USER, &ext3_xattr_user_handler);
+ ext3_xattr_unregister(EXT3_XATTR_INDEX_TRUSTED,
+ &ext3_xattr_trusted_handler);
+ ext3_xattr_unregister(EXT3_XATTR_INDEX_USER,
+ &ext3_xattr_user_handler);
}
Index: linux-2.5.60/fs/ext3/xattr.h
--- linux-2.5.60~xattr-trusted/fs/ext3/xattr.h 2003-02-11 12:39:17.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.h 2003-02-11 12:47:41.000000000 +0100
@@ -20,6 +20,7 @@
#define EXT3_XATTR_INDEX_USER 1
#define EXT3_XATTR_INDEX_POSIX_ACL_ACCESS 2
#define EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT 3
+#define EXT3_XATTR_INDEX_TRUSTED 4
struct ext3_xattr_header {
__u32 h_magic; /* magic number for identification */
@@ -139,3 +140,4 @@
# endif /* CONFIG_EXT3_FS_XATTR */
extern struct ext3_xattr_handler ext3_xattr_user_handler;
+extern struct ext3_xattr_handler ext3_xattr_trusted_handler;
Index: linux-2.5.60/fs/ext3/xattr_trusted.c
--- linux-2.5.60~xattr-trusted/fs/ext3/xattr_trusted.c 2003-02-11 12:47:41.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr_trusted.c 2003-02-11 12:47:41.000000000 +0100
@@ -0,0 +1,64 @@
+/*
+ * linux/fs/ext3/xattr_trusted.c
+ * Handler for trusted extended attributes.
+ *
+ * Copyright (C) 2003 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.h>
+#include <linux/ext3_jbd.h>
+#include <linux/ext3_fs.h>
+#include "xattr.h"
+
+#define XATTR_TRUSTED_PREFIX "trusted."
+
+static size_t
+ext3_xattr_trusted_list(char *list, struct inode *inode,
+ const char *name, int name_len, int flags)
+{
+ const int prefix_len = sizeof(XATTR_TRUSTED_PREFIX)-1;
+
+ if (!((flags & XATTR_KERNEL_CONTEXT) || capable(CAP_SYS_ADMIN)))
+ return 0;
+
+ if (list) {
+ memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
+ memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
+ }
+ return prefix_len + name_len + 1;
+}
+
+static int
+ext3_xattr_trusted_get(struct inode *inode, const char *name,
+ void *buffer, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ if (!((flags & XATTR_KERNEL_CONTEXT) || capable(CAP_SYS_ADMIN)))
+ return -EPERM;
+ return ext3_xattr_get(inode, EXT3_XATTR_INDEX_TRUSTED, name,
+ buffer, size);
+}
+
+static int
+ext3_xattr_trusted_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ if (!((flags & XATTR_KERNEL_CONTEXT) || capable(CAP_SYS_ADMIN)))
+ return -EPERM;
+ return ext3_xattr_set(inode, EXT3_XATTR_INDEX_TRUSTED, name,
+ value, size, flags);
+}
+
+struct ext3_xattr_handler ext3_xattr_trusted_handler = {
+ .prefix = XATTR_TRUSTED_PREFIX,
+ .list = ext3_xattr_trusted_list,
+ .get = ext3_xattr_trusted_get,
+ .set = ext3_xattr_trusted_set,
+};
[-- Attachment #5: xattr-flags-policy.diff --]
[-- Type: text/x-diff, Size: 5062 bytes --]
This adds the XATTR_KERNEL_CONTEXT extended attributes flag. Kernel
code may use this flag to override extended attribute permission
restrictions that would otherwise be imposed on the calling process.
--- linux-2.5.60~xattr-flags-policy/fs/ext2/xattr_user.c 2003-02-11 12:40:20.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr_user.c 2003-02-11 12:40:29.000000000 +0100
@@ -23,7 +23,8 @@
{
const int prefix_len = sizeof(XATTR_USER_PREFIX)-1;
- if (!test_opt(inode->i_sb, XATTR_USER))
+ if (!(flags & XATTR_KERNEL_CONTEXT) &&
+ !test_opt(inode->i_sb, XATTR_USER))
return 0;
if (list) {
@@ -38,20 +39,21 @@
ext2_xattr_user_get(struct inode *inode, const char *name,
void *buffer, size_t size, int flags)
{
- int error;
-
if (strcmp(name, "") == 0)
return -EINVAL;
- if (!test_opt(inode->i_sb, XATTR_USER))
- return -EOPNOTSUPP;
+ if (!(flags & XATTR_KERNEL_CONTEXT)) {
+ int error;
+
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return -EOPNOTSUPP;
#ifdef CONFIG_EXT2_FS_POSIX_ACL
- error = ext2_permission_locked(inode, MAY_READ);
+ error = ext2_permission_locked(inode, MAY_READ);
#else
- error = permission(inode, MAY_READ);
+ error = permission(inode, MAY_READ);
#endif
- if (error)
- return error;
-
+ if (error)
+ return error;
+ }
return ext2_xattr_get(inode, EXT2_XATTR_INDEX_USER, name,
buffer, size);
}
@@ -60,23 +62,24 @@
ext2_xattr_user_set(struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
- int error;
-
if (strcmp(name, "") == 0)
return -EINVAL;
- if (!test_opt(inode->i_sb, XATTR_USER))
- return -EOPNOTSUPP;
if ( !S_ISREG(inode->i_mode) &&
(!S_ISDIR(inode->i_mode) || inode->i_mode & S_ISVTX))
return -EPERM;
+ if (!(flags & XATTR_KERNEL_CONTEXT)) {
+ int error;
+
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return -EOPNOTSUPP;
#ifdef CONFIG_EXT2_FS_POSIX_ACL
- error = ext2_permission_locked(inode, MAY_WRITE);
+ error = ext2_permission_locked(inode, MAY_WRITE);
#else
- error = permission(inode, MAY_WRITE);
+ error = permission(inode, MAY_WRITE);
#endif
- if (error)
- return error;
-
+ if (error)
+ return error;
+ }
return ext2_xattr_set(inode, EXT2_XATTR_INDEX_USER, name,
value, size, flags);
}
Index: linux-2.5.60/fs/ext3/xattr_user.c
--- linux-2.5.60~xattr-flags-policy/fs/ext3/xattr_user.c 2003-02-11 12:40:20.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr_user.c 2003-02-11 12:46:12.000000000 +0100
@@ -25,7 +25,8 @@
{
const int prefix_len = sizeof(XATTR_USER_PREFIX)-1;
- if (!test_opt(inode->i_sb, XATTR_USER))
+ if (!(flags & XATTR_KERNEL_CONTEXT) &&
+ !test_opt(inode->i_sb, XATTR_USER))
return 0;
if (list) {
@@ -40,20 +41,21 @@
ext3_xattr_user_get(struct inode *inode, const char *name,
void *buffer, size_t size, int flags)
{
- int error;
-
if (strcmp(name, "") == 0)
return -EINVAL;
- if (!test_opt(inode->i_sb, XATTR_USER))
- return -EOPNOTSUPP;
+ if (!(flags & XATTR_KERNEL_CONTEXT)) {
+ int error;
+
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return -EOPNOTSUPP;
#ifdef CONFIG_EXT3_FS_POSIX_ACL
- error = ext3_permission_locked(inode, MAY_READ);
+ error = ext3_permission_locked(inode, MAY_READ);
#else
- error = permission(inode, MAY_READ);
+ error = permission(inode, MAY_READ);
#endif
- if (error)
- return error;
-
+ if (error)
+ return error;
+ }
return ext3_xattr_get(inode, EXT3_XATTR_INDEX_USER, name,
buffer, size);
}
@@ -62,26 +64,26 @@
ext3_xattr_user_set(struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
- int error;
-
if (strcmp(name, "") == 0)
return -EINVAL;
- if (!test_opt(inode->i_sb, XATTR_USER))
- return -EOPNOTSUPP;
if ( !S_ISREG(inode->i_mode) &&
(!S_ISDIR(inode->i_mode) || inode->i_mode & S_ISVTX))
return -EPERM;
+ if (!(flags & XATTR_KERNEL_CONTEXT)) {
+ int error;
+
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return -EOPNOTSUPP;
#ifdef CONFIG_EXT3_FS_POSIX_ACL
- error = ext3_permission_locked(inode, MAY_WRITE);
+ error = ext3_permission_locked(inode, MAY_WRITE);
#else
- error = permission(inode, MAY_WRITE);
+ error = permission(inode, MAY_WRITE);
#endif
- if (error)
- return error;
-
+ if (error)
+ return error;
+ }
return ext3_xattr_set(inode, EXT3_XATTR_INDEX_USER, name,
value, size, flags);
-
}
struct ext3_xattr_handler ext3_xattr_user_handler = {
Index: linux-2.5.60/include/linux/xattr.h
--- linux-2.5.60~xattr-flags-policy/include/linux/xattr.h 2003-02-10 19:38:44.000000000 +0100
+++ linux-2.5.60/include/linux/xattr.h 2003-02-11 12:40:29.000000000 +0100
@@ -9,7 +9,8 @@
#ifndef _LINUX_XATTR_H
#define _LINUX_XATTR_H
-#define XATTR_CREATE 0x1 /* set value, fail if attr already exists */
-#define XATTR_REPLACE 0x2 /* set value, fail if attr does not exist */
+#define XATTR_CREATE 0x1 /* fail if attr already exists */
+#define XATTR_REPLACE 0x2 /* fail if attr does not exist */
+#define XATTR_KERNEL_CONTEXT 0x4 /* called from kernel context */
#endif /* _LINUX_XATTR_H */
[-- Attachment #6: xattr-flags.diff --]
[-- Type: text/x-diff, Size: 16205 bytes --]
This adds flags parameters to the getxattr, listxattr, and removexattr
inode operations. This is in preparation for the next patch, which
allows in-kernel code (i.e., modules) to override extended attribute
permission restrictions (which in turn is used by HSM implementations
and the like).
Index: linux-2.5.60/fs/ext2/acl.c
--- linux-2.5.60~xattr-flags/fs/ext2/acl.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext2/acl.c 2003-02-11 13:56:43.000000000 +0100
@@ -419,7 +419,7 @@
*/
static size_t
ext2_xattr_list_acl_access(char *list, struct inode *inode,
- const char *name, int name_len)
+ const char *name, int name_len, int flags)
{
const size_t size = sizeof(XATTR_NAME_ACL_ACCESS);
@@ -432,7 +432,7 @@
static size_t
ext2_xattr_list_acl_default(char *list, struct inode *inode,
- const char *name, int name_len)
+ const char *name, int name_len, int flags)
{
const size_t size = sizeof(XATTR_NAME_ACL_DEFAULT);
@@ -465,7 +465,7 @@
static int
ext2_xattr_get_acl_access(struct inode *inode, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
if (strcmp(name, "") != 0)
return -EINVAL;
@@ -474,7 +474,7 @@
static int
ext2_xattr_get_acl_default(struct inode *inode, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
if (strcmp(name, "") != 0)
return -EINVAL;
@@ -482,7 +482,8 @@
}
static int
-ext2_xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
+ext2_xattr_set_acl(struct inode *inode, int type, const void *value,
+ size_t size)
{
struct posix_acl *acl;
int error;
Index: linux-2.5.60/fs/ext2/xattr.c
--- linux-2.5.60~xattr-flags/fs/ext2/xattr.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr.c 2003-02-11 13:56:43.000000000 +0100
@@ -199,7 +199,7 @@
*/
ssize_t
ext2_getxattr(struct dentry *dentry, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
struct ext2_xattr_handler *handler;
struct inode *inode = dentry->d_inode;
@@ -207,7 +207,7 @@
handler = ext2_xattr_resolve_name(&name);
if (!handler)
return -EOPNOTSUPP;
- return handler->get(inode, name, buffer, size);
+ return handler->get(inode, name, buffer, size, flags);
}
/*
@@ -217,9 +217,9 @@
* BKL held [before 2.5.x]
*/
ssize_t
-ext2_listxattr(struct dentry *dentry, char *buffer, size_t size)
+ext2_listxattr(struct dentry *dentry, char *buffer, size_t size, int flags)
{
- return ext2_xattr_list(dentry->d_inode, buffer, size);
+ return ext2_xattr_list(dentry->d_inode, buffer, size, flags);
}
/*
@@ -250,7 +250,7 @@
* BKL held [before 2.5.x]
*/
int
-ext2_removexattr(struct dentry *dentry, const char *name)
+ext2_removexattr(struct dentry *dentry, const char *name, int flags)
{
struct ext2_xattr_handler *handler;
struct inode *inode = dentry->d_inode;
@@ -258,7 +258,7 @@
handler = ext2_xattr_resolve_name(&name);
if (!handler)
return -EOPNOTSUPP;
- return handler->set(inode, name, NULL, 0, XATTR_REPLACE);
+ return handler->set(inode, name, NULL, 0, flags | XATTR_REPLACE);
}
/*
@@ -371,7 +371,8 @@
* used / required on success.
*/
int
-ext2_xattr_list(struct inode *inode, char *buffer, size_t buffer_size)
+ext2_xattr_list(struct inode *inode, char *buffer, size_t buffer_size,
+ int flags)
{
struct buffer_head *bh = NULL;
struct ext2_xattr_entry *entry;
@@ -411,7 +412,7 @@
handler = ext2_xattr_handler(entry->e_name_index);
if (handler)
size += handler->list(NULL, inode, entry->e_name,
- entry->e_name_len);
+ entry->e_name_len, flags);
}
if (ext2_xattr_cache_insert(bh))
@@ -434,7 +435,7 @@
handler = ext2_xattr_handler(entry->e_name_index);
if (handler)
buf += handler->list(buf, inode, entry->e_name,
- entry->e_name_len);
+ entry->e_name_len, flags);
}
error = size;
Index: linux-2.5.60/fs/ext2/xattr.h
--- linux-2.5.60~xattr-flags/fs/ext2/xattr.h 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr.h 2003-02-11 14:02:30.000000000 +0100
@@ -57,9 +57,9 @@
struct ext2_xattr_handler {
char *prefix;
size_t (*list)(char *list, struct inode *inode, const char *name,
- int name_len);
+ int name_len, int flags);
int (*get)(struct inode *inode, const char *name, void *buffer,
- size_t size);
+ size_t size, int flags);
int (*set)(struct inode *inode, const char *name, const void *buffer,
size_t size, int flags);
};
@@ -68,12 +68,12 @@
extern void ext2_xattr_unregister(int, struct ext2_xattr_handler *);
extern int ext2_setxattr(struct dentry *, const char *, const void *, size_t, int);
-extern ssize_t ext2_getxattr(struct dentry *, const char *, void *, size_t);
-extern ssize_t ext2_listxattr(struct dentry *, char *, size_t);
-extern int ext2_removexattr(struct dentry *, const char *);
+extern ssize_t ext2_getxattr(struct dentry *, const char *, void *, size_t, int);
+extern ssize_t ext2_listxattr(struct dentry *, char *, size_t, int);
+extern int ext2_removexattr(struct dentry *, const char *, int);
extern int ext2_xattr_get(struct inode *, int, const char *, void *, size_t);
-extern int ext2_xattr_list(struct inode *, char *, size_t);
+extern int ext2_xattr_list(struct inode *, char *, size_t, int flags);
extern int ext2_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
extern void ext2_xattr_delete_inode(struct inode *);
Index: linux-2.5.60/fs/ext2/xattr_user.c
--- linux-2.5.60~xattr-flags/fs/ext2/xattr_user.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext2/xattr_user.c 2003-02-11 13:56:43.000000000 +0100
@@ -19,7 +19,7 @@
static size_t
ext2_xattr_user_list(char *list, struct inode *inode,
- const char *name, int name_len)
+ const char *name, int name_len, int flags)
{
const int prefix_len = sizeof(XATTR_USER_PREFIX)-1;
@@ -36,7 +36,7 @@
static int
ext2_xattr_user_get(struct inode *inode, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
int error;
Index: linux-2.5.60/fs/ext3/acl.c
--- linux-2.5.60~xattr-flags/fs/ext3/acl.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext3/acl.c 2003-02-11 13:56:43.000000000 +0100
@@ -432,7 +432,7 @@
*/
static size_t
ext3_xattr_list_acl_access(char *list, struct inode *inode,
- const char *name, int name_len)
+ const char *name, int name_len, int flags)
{
const size_t size = sizeof(XATTR_NAME_ACL_ACCESS);
@@ -445,7 +445,7 @@
static size_t
ext3_xattr_list_acl_default(char *list, struct inode *inode,
- const char *name, int name_len)
+ const char *name, int name_len, int flags)
{
const size_t size = sizeof(XATTR_NAME_ACL_DEFAULT);
@@ -478,7 +478,7 @@
static int
ext3_xattr_get_acl_access(struct inode *inode, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
if (strcmp(name, "") != 0)
return -EINVAL;
@@ -487,7 +487,7 @@
static int
ext3_xattr_get_acl_default(struct inode *inode, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
if (strcmp(name, "") != 0)
return -EINVAL;
@@ -495,7 +495,8 @@
}
static int
-ext3_xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
+ext3_xattr_set_acl(struct inode *inode, int type, const void *value,
+ size_t size)
{
handle_t *handle;
struct posix_acl *acl;
Index: linux-2.5.60/fs/ext3/xattr.c
--- linux-2.5.60~xattr-flags/fs/ext3/xattr.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.c 2003-02-11 13:56:43.000000000 +0100
@@ -195,7 +195,7 @@
*/
ssize_t
ext3_getxattr(struct dentry *dentry, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
struct ext3_xattr_handler *handler;
struct inode *inode = dentry->d_inode;
@@ -203,7 +203,7 @@
handler = ext3_xattr_resolve_name(&name);
if (!handler)
return -EOPNOTSUPP;
- return handler->get(inode, name, buffer, size);
+ return handler->get(inode, name, buffer, size, flags);
}
/*
@@ -212,9 +212,9 @@
* dentry->d_inode->i_sem down
*/
ssize_t
-ext3_listxattr(struct dentry *dentry, char *buffer, size_t size)
+ext3_listxattr(struct dentry *dentry, char *buffer, size_t size, int flags)
{
- return ext3_xattr_list(dentry->d_inode, buffer, size);
+ return ext3_xattr_list(dentry->d_inode, buffer, size, flags);
}
/*
@@ -243,7 +243,7 @@
* dentry->d_inode->i_sem down
*/
int
-ext3_removexattr(struct dentry *dentry, const char *name)
+ext3_removexattr(struct dentry *dentry, const char *name, int flags)
{
struct ext3_xattr_handler *handler;
struct inode *inode = dentry->d_inode;
@@ -251,7 +251,7 @@
handler = ext3_xattr_resolve_name(&name);
if (!handler)
return -EOPNOTSUPP;
- return handler->set(inode, name, NULL, 0, XATTR_REPLACE);
+ return handler->set(inode, name, NULL, 0, flags | XATTR_REPLACE);
}
/*
@@ -364,7 +364,8 @@
* used / required on success.
*/
int
-ext3_xattr_list(struct inode *inode, char *buffer, size_t buffer_size)
+ext3_xattr_list(struct inode *inode, char *buffer, size_t buffer_size,
+ int flags)
{
struct buffer_head *bh = NULL;
struct ext3_xattr_entry *entry;
@@ -404,7 +405,7 @@
handler = ext3_xattr_handler(entry->e_name_index);
if (handler)
size += handler->list(NULL, inode, entry->e_name,
- entry->e_name_len);
+ entry->e_name_len, flags);
}
if (ext3_xattr_cache_insert(bh))
@@ -427,7 +428,7 @@
handler = ext3_xattr_handler(entry->e_name_index);
if (handler)
buf += handler->list(buf, inode, entry->e_name,
- entry->e_name_len);
+ entry->e_name_len, flags);
}
error = size;
Index: linux-2.5.60/fs/ext3/xattr.h
--- linux-2.5.60~xattr-flags/fs/ext3/xattr.h 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.h 2003-02-11 14:00:59.000000000 +0100
@@ -56,9 +56,9 @@
struct ext3_xattr_handler {
char *prefix;
size_t (*list)(char *list, struct inode *inode, const char *name,
- int name_len);
+ int name_len, int flags);
int (*get)(struct inode *inode, const char *name, void *buffer,
- size_t size);
+ size_t size, int flags);
int (*set)(struct inode *inode, const char *name, const void *buffer,
size_t size, int flags);
};
@@ -67,12 +67,12 @@
extern void ext3_xattr_unregister(int, struct ext3_xattr_handler *);
extern int ext3_setxattr(struct dentry *, const char *, const void *, size_t, int);
-extern ssize_t ext3_getxattr(struct dentry *, const char *, void *, size_t);
-extern ssize_t ext3_listxattr(struct dentry *, char *, size_t);
-extern int ext3_removexattr(struct dentry *, const char *);
+extern ssize_t ext3_getxattr(struct dentry *, const char *, void *, size_t, int);
+extern ssize_t ext3_listxattr(struct dentry *, char *, size_t, int);
+extern int ext3_removexattr(struct dentry *, const char *, int);
extern int ext3_xattr_get(struct inode *, int, const char *, void *, size_t);
-extern int ext3_xattr_list(struct inode *, char *, size_t);
+extern int ext3_xattr_list(struct inode *, char *, size_t, int flags);
extern int ext3_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
extern int ext3_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
Index: linux-2.5.60/fs/ext3/xattr_user.c
--- linux-2.5.60~xattr-flags/fs/ext3/xattr_user.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr_user.c 2003-02-11 13:56:43.000000000 +0100
@@ -21,7 +21,7 @@
static size_t
ext3_xattr_user_list(char *list, struct inode *inode,
- const char *name, int name_len)
+ const char *name, int name_len, int flags)
{
const int prefix_len = sizeof(XATTR_USER_PREFIX)-1;
@@ -38,7 +38,7 @@
static int
ext3_xattr_user_get(struct inode *inode, const char *name,
- void *buffer, size_t size)
+ void *buffer, size_t size, int flags)
{
int error;
Index: linux-2.5.60/fs/xattr.c
--- linux-2.5.60~xattr-flags/fs/xattr.c 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/fs/xattr.c 2003-02-11 13:56:43.000000000 +0100
@@ -160,7 +160,7 @@
if (error)
goto out;
down(&d->d_inode->i_sem);
- error = d->d_inode->i_op->getxattr(d, kname, kvalue, size);
+ error = d->d_inode->i_op->getxattr(d, kname, kvalue, size, 0);
up(&d->d_inode->i_sem);
}
@@ -233,7 +233,7 @@
if (error)
goto out;
down(&d->d_inode->i_sem);
- error = d->d_inode->i_op->listxattr(d, klist, size);
+ error = d->d_inode->i_op->listxattr(d, klist, size, 0);
up(&d->d_inode->i_sem);
}
@@ -308,7 +308,7 @@
if (error)
goto out;
down(&d->d_inode->i_sem);
- error = d->d_inode->i_op->removexattr(d, kname);
+ error = d->d_inode->i_op->removexattr(d, kname, 0);
up(&d->d_inode->i_sem);
}
out:
Index: linux-2.5.60/include/linux/fs.h
--- linux-2.5.60~xattr-flags/include/linux/fs.h 2003-02-11 13:56:41.000000000 +0100
+++ linux-2.5.60/include/linux/fs.h 2003-02-11 13:56:43.000000000 +0100
@@ -743,9 +743,9 @@
int (*setattr) (struct dentry *, struct iattr *);
int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
- ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
- ssize_t (*listxattr) (struct dentry *, char *, size_t);
- int (*removexattr) (struct dentry *, const char *);
+ ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t,int);
+ ssize_t (*listxattr) (struct dentry *, char *, size_t, int);
+ int (*removexattr) (struct dentry *, const char *, int);
};
struct seq_file;
Index: linux-2.5.60/fs/jfs/xattr.c
--- linux-2.5.60~xattr-flags/fs/jfs/xattr.c 2003-02-10 19:38:20.000000000 +0100
+++ linux-2.5.60/fs/jfs/xattr.c 2003-02-11 14:07:06.000000000 +0100
@@ -962,12 +962,13 @@
}
ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data,
- size_t buf_size)
+ size_t buf_size, int flags)
{
return __jfs_getxattr(dentry->d_inode, name, data, buf_size);
}
-ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size)
+ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size,
+ int flags)
{
struct inode *inode = dentry->d_inode;
char *buffer;
@@ -1013,7 +1014,7 @@
return size;
}
-int jfs_removexattr(struct dentry *dentry, const char *name)
+int jfs_removexattr(struct dentry *dentry, const char *name, int flags)
{
return __jfs_setxattr(dentry->d_inode, name, 0, 0, XATTR_REPLACE);
}
Index: linux-2.5.60/fs/jfs/jfs_xattr.h
--- linux-2.5.60~xattr-flags/fs/jfs/jfs_xattr.h 2003-02-10 19:38:52.000000000 +0100
+++ linux-2.5.60/fs/jfs/jfs_xattr.h 2003-02-11 14:07:49.000000000 +0100
@@ -57,8 +57,8 @@
extern int jfs_setxattr(struct dentry *, const char *, const void *, size_t,
int);
extern ssize_t __jfs_getxattr(struct inode *, const char *, void *, size_t);
-extern ssize_t jfs_getxattr(struct dentry *, const char *, void *, size_t);
-extern ssize_t jfs_listxattr(struct dentry *, char *, size_t);
-extern int jfs_removexattr(struct dentry *, const char *);
+extern ssize_t jfs_getxattr(struct dentry *, const char *, void *, size_t, int);
+extern ssize_t jfs_listxattr(struct dentry *, char *, size_t, int);
+extern int jfs_removexattr(struct dentry *, const char *, int);
#endif /* H_JFS_XATTR */
Index: linux-2.5.60/fs/xfs/linux/xfs_iops.c
--- linux-2.5.60~xattr-flags/fs/xfs/linux/xfs_iops.c 2003-02-10 19:38:17.000000000 +0100
+++ linux-2.5.60/fs/xfs/linux/xfs_iops.c 2003-02-11 14:10:51.000000000 +0100
@@ -640,7 +640,8 @@
struct dentry *dentry,
const char *name,
void *data,
- size_t size)
+ size_t size,
+ int flags)
{
ssize_t error;
int xflags = 0;
@@ -697,7 +698,8 @@
linvfs_listxattr(
struct dentry *dentry,
char *data,
- size_t size)
+ size_t size,
+ int flags)
{
ssize_t error;
int result = 0;
@@ -741,7 +743,8 @@
STATIC int
linvfs_removexattr(
struct dentry *dentry,
- const char *name)
+ const char *name,
+ int flags)
{
int error;
int xflags = 0;
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-11 19:18 [PATCH] Extended attribute fixes, etc Andreas Gruenbacher
@ 2003-02-11 20:32 ` Andrew Morton
2003-02-12 11:03 ` Andreas Gruenbacher
2003-02-15 11:07 ` Christoph Hellwig
1 sibling, 1 reply; 9+ messages in thread
From: Andrew Morton @ 2003-02-11 20:32 UTC (permalink / raw)
To: Andreas Gruenbacher; +Cc: linux-kernel, tytso
Andreas Gruenbacher <agruen@suse.de> wrote:
>
> Hi Andrew,
>
> here are five patches against 2.5.60. Each file contains a brief
> description of what it does.
>
Minor point:
> int
> ext3_xattr_set(struct inode *inode, int name_index, const char *name,
> const void *value, size_t value_len, int flags)
> {
> handle_t *handle;
> int error;
>
> lock_kernel();
> handle = ext3_journal_start(inode, EXT3_XATTR_TRANS_BLOCKS);
> if (IS_ERR(handle))
> error = PTR_ERR(handle);
> else
> error = ext3_xattr_set_handle(handle, inode, name_index, name,
> value, value_len, flags);
> ext3_journal_stop(handle, inode);
ext3_journal_stop() can return an error code - most notable -EIO if it was a
synchronous transaction, or the filesystem has detected corruption.
> The third to fifth are all steps towards trusted extended attributes,
> which are useful for privileged processes (mostly daemons). One use for
> this is Hierarchical Storage Management, in which a user space daemon
> stores online/offline information for files in trusted EA's, and the
> kernel communicates requests to bring files online to that daemon. This
> class of EA's will also find its way into XFS and ReiserFS, and
> expectedly also into JFS in this form. (Trusted EAs are included in the
> 2.4.19/2.4.20 patches as well.)
So is this new code actually functional yet? As in: something in-kernel
using it?
If not, what is involved in completing the kernel side of trusted EA's?
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-11 20:32 ` Andrew Morton
@ 2003-02-12 11:03 ` Andreas Gruenbacher
0 siblings, 0 replies; 9+ messages in thread
From: Andreas Gruenbacher @ 2003-02-12 11:03 UTC (permalink / raw)
To: Andrew Morton; +Cc: linux-kernel, tytso
[-- Attachment #1: Type: text/plain, Size: 1869 bytes --]
On Tuesday 11 February 2003 21:32, Andrew Morton wrote:
> Andreas Gruenbacher <agruen@suse.de> wrote:
> > Hi Andrew,
> >
> > here are five patches against 2.5.60. Each file contains a brief
> > description of what it does.
>
> Minor point:
> ext3_journal_stop() can return an error code - most notable -EIO if
> it was a synchronous transaction, or the filesystem has detected
> corruption.
Thanks, I have overlooked this third bug. An incremental patch on top of
my previous kernel_lock_bug.diff is attached. (I have also uploaded the
patches to <http://acl.bestbits.at/pre/v2.5/> in the meantime).
> > The third to fifth are all steps towards trusted extended
> > attributes, which are useful for privileged processes (mostly
> > daemons). One use for this is Hierarchical Storage Management, in
> > which a user space daemon stores online/offline information for
> > files in trusted EA's, and the kernel communicates requests to
> > bring files online to that daemon. This class of EA's will also
> > find its way into XFS and ReiserFS, and expectedly also into JFS in
> > this form. (Trusted EAs are included in the 2.4.19/2.4.20 patches
> > as well.)
>
> So is this new code actually functional yet? As in: something
> in-kernel using it?
>
> If not, what is involved in completing the kernel side of trusted
> EA's?
The important point for me now is to get the iops xattr-flags and
xattr-flags-policy patches into 2.5 so that the API won't change during
2.6. The xattr-trusted patch only affects file systems locally, so it's
far less critical.
The kernel side of trusted EAs is completely implemented with the
patches I sent. In the future there will very likely be modules
actually making use of the XATTR_KERNEL_CONTEXT flag, but Trusted EAs
are quite useful from user space alone.
Cheers,
Andreas.
[-- Attachment #2: kernel_lock_bug2.diff --]
[-- Type: text/x-diff, Size: 713 bytes --]
diff -u linux-2.5.60/fs/ext3/xattr.c linux-2.5.60/fs/ext3/xattr.c
--- linux-2.5.60/fs/ext3/xattr.c 2003-02-11 12:33:45.000000000 +0100
+++ linux-2.5.60/fs/ext3/xattr.c 2003-02-12 11:18:18.000000000 +0100
@@ -848,7 +848,7 @@
const void *value, size_t value_len, int flags)
{
handle_t *handle;
- int error;
+ int error, error2;
lock_kernel();
handle = ext3_journal_start(inode, EXT3_XATTR_TRANS_BLOCKS);
@@ -857,10 +857,10 @@
else
error = ext3_xattr_set_handle(handle, inode, name_index, name,
value, value_len, flags);
- ext3_journal_stop(handle, inode);
+ error2 = ext3_journal_stop(handle, inode);
unlock_kernel();
- return error;
+ return error ? error : error2;
}
/*
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-11 19:18 [PATCH] Extended attribute fixes, etc Andreas Gruenbacher
2003-02-11 20:32 ` Andrew Morton
@ 2003-02-15 11:07 ` Christoph Hellwig
2003-02-15 17:59 ` Andreas Gruenbacher
1 sibling, 1 reply; 9+ messages in thread
From: Christoph Hellwig @ 2003-02-15 11:07 UTC (permalink / raw)
To: Andreas Gruenbacher; +Cc: Andrew Morton, linux-kernel, Theodore T'so
On Tue, Feb 11, 2003 at 08:18:58PM +0100, Andreas Gruenbacher wrote:
> The third to fifth are all steps towards trusted extended attributes,
> which are useful for privileged processes (mostly daemons). One use for
> this is Hierarchical Storage Management, in which a user space daemon
> stores online/offline information for files in trusted EA's, and the
> kernel communicates requests to bring files online to that daemon. This
> class of EA's will also find its way into XFS and ReiserFS, and
> expectedly also into JFS in this form. (Trusted EAs are included in the
> 2.4.19/2.4.20 patches as well.)
Please don't do the ugly flags stuff. We have fsuids and fsgids for exactly
that reason (and because we're still lacking a credentials cache..).
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-15 11:07 ` Christoph Hellwig
@ 2003-02-15 17:59 ` Andreas Gruenbacher
2003-02-15 18:39 ` Christoph Hellwig
0 siblings, 1 reply; 9+ messages in thread
From: Andreas Gruenbacher @ 2003-02-15 17:59 UTC (permalink / raw)
To: Christoph Hellwig; +Cc: Andrew Morton, linux-kernel, Theodore T'so
On Saturday 15 February 2003 12:07, Christoph Hellwig wrote:
> On Tue, Feb 11, 2003 at 08:18:58PM +0100, Andreas Gruenbacher wrote:
> > The third to fifth are all steps towards trusted extended
> > attributes, which are useful for privileged processes (mostly
> > daemons). One use for this is Hierarchical Storage Management, in
> > which a user space daemon stores online/offline information for
> > files in trusted EA's, and the kernel communicates requests to
> > bring files online to that daemon. This class of EA's will also
> > find its way into XFS and ReiserFS, and expectedly also into JFS in
> > this form. (Trusted EAs are included in the 2.4.19/2.4.20 patches
> > as well.)
>
> Please don't do the ugly flags stuff. We have fsuids and fsgids for
> exactly that reason (and because we're still lacking a credentials
> cache..).
The XATTR_KERNEL_CONTEXT flag cannot be substituted by a uid/gid change;
it is unrelated to that; that's the whole point of it. It would be
possible to raise some other flag (such as a capability, etc.) instead
of passing an explicit flag, but that seems uglier and more
problematic/error prone to me.
-- Andreas.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-15 17:59 ` Andreas Gruenbacher
@ 2003-02-15 18:39 ` Christoph Hellwig
2003-02-15 19:17 ` Andreas Gruenbacher
0 siblings, 1 reply; 9+ messages in thread
From: Christoph Hellwig @ 2003-02-15 18:39 UTC (permalink / raw)
To: Andreas Gruenbacher
Cc: Christoph Hellwig, Andrew Morton, linux-kernel, Theodore T'so
On Sat, Feb 15, 2003 at 06:59:11PM +0100, Andreas Gruenbacher wrote:
> > Please don't do the ugly flags stuff. We have fsuids and fsgids for
> > exactly that reason (and because we're still lacking a credentials
> > cache..).
>
> The XATTR_KERNEL_CONTEXT flag cannot be substituted by a uid/gid change;
> it is unrelated to that; that's the whole point of it. It would be
> possible to raise some other flag (such as a capability, etc.) instead
> of passing an explicit flag, but that seems uglier and more
> problematic/error prone to me.
Then raise CAP_DAC_OVERRIDE. The right thing would be to pass down a
struct cred, so we could pass down the magic sys_cred that allows all
access (look at the XFS ACL code for details on that..), but
unfortuantately we still don't have proper credentials although there
were numerous patches around in the last years and we really want it
for other reasons.
Magic flags that change the DAC checks work are ugly and will most
certainly lead to bugs in some implementations sooner or later.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-15 18:39 ` Christoph Hellwig
@ 2003-02-15 19:17 ` Andreas Gruenbacher
2003-02-15 21:09 ` Christoph Hellwig
0 siblings, 1 reply; 9+ messages in thread
From: Andreas Gruenbacher @ 2003-02-15 19:17 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Christoph Hellwig, Andrew Morton, linux-kernel, Theodore T'so
On Saturday 15 February 2003 19:39, Christoph Hellwig wrote:
> On Sat, Feb 15, 2003 at 06:59:11PM +0100, Andreas Gruenbacher wrote:
> > > Please don't do the ugly flags stuff. We have fsuids and fsgids
> > > for exactly that reason (and because we're still lacking a
> > > credentials cache..).
> >
> > The XATTR_KERNEL_CONTEXT flag cannot be substituted by a uid/gid
> > change; it is unrelated to that; that's the whole point of it. It
> > would be possible to raise some other flag (such as a capability,
> > etc.) instead of passing an explicit flag, but that seems uglier
> > and more problematic/error prone to me.
>
> Then raise CAP_DAC_OVERRIDE. The right thing would be to pass down a
> struct cred, so we could pass down the magic sys_cred that allows all
> access (look at the XFS ACL code for details on that..), but
> unfortuantately we still don't have proper credentials although there
> were numerous patches around in the last years and we really want it
> for other reasons.
That sounds quite reasonable. I would have to raise CAP_SYS_ADMIN for
trusted EA's, though. Do you see any potential side effects while a
pretty powerful capability like CAP_SYS_ADMIN is temporarily raised?
> Magic flags that change the DAC checks work are ugly and will most
> certainly lead to bugs in some implementations sooner or later.
Maybe.
Thanks,
Andreas.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-15 19:17 ` Andreas Gruenbacher
@ 2003-02-15 21:09 ` Christoph Hellwig
2003-02-15 21:39 ` Andreas Gruenbacher
0 siblings, 1 reply; 9+ messages in thread
From: Christoph Hellwig @ 2003-02-15 21:09 UTC (permalink / raw)
To: Andreas Gruenbacher; +Cc: Andrew Morton, linux-kernel, Theodore T'so
On Sat, Feb 15, 2003 at 08:17:03PM +0100, Andreas Gruenbacher wrote:
> That sounds quite reasonable. I would have to raise CAP_SYS_ADMIN for
> trusted EA's, though. Do you see any potential side effects while a
> pretty powerful capability like CAP_SYS_ADMIN is temporarily raised?
Okay, something I missed when looking over your patches, otherwise I'd
have shutde earlier :) Do you really think you want CAP_SYS_ADMIN for
trusted EAs? Soon we'll get CAP_SYS_ADMIN as catchall like old suser()..
Let me check what XFS uses for that purpose as soon as I'm back in the
office.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Extended attribute fixes, etc.
2003-02-15 21:09 ` Christoph Hellwig
@ 2003-02-15 21:39 ` Andreas Gruenbacher
0 siblings, 0 replies; 9+ messages in thread
From: Andreas Gruenbacher @ 2003-02-15 21:39 UTC (permalink / raw)
To: Christoph Hellwig; +Cc: Andrew Morton, linux-kernel, Theodore T'so
On Saturday 15 February 2003 22:09, Christoph Hellwig wrote:
> On Sat, Feb 15, 2003 at 08:17:03PM +0100, Andreas Gruenbacher wrote:
> > That sounds quite reasonable. I would have to raise CAP_SYS_ADMIN
> > for trusted EA's, though. Do you see any potential side effects
> > while a pretty powerful capability like CAP_SYS_ADMIN is
> > temporarily raised?
>
> Okay, something I missed when looking over your patches, otherwise
> I'd have shutde earlier :) Do you really think you want
> CAP_SYS_ADMIN for trusted EAs? Soon we'll get CAP_SYS_ADMIN as
> catchall like old suser()..
>
> Let me check what XFS uses for that purpose as soon as I'm back in
> the office.
The intention of Trusted Extended Attributes is for processes that
perform tasks that are relevant for the proper functioning of the
system, to allow them to use EAs. Other, non-privileged processes shall
have no access whatsoever to those EAs. This level of protection would
otherwise only be possible by providing a kernel module.
I would be quite happy with a new CAP_TRUSTED_PROCESS or whatever, but
going that route for all sorts of applications then we might soon end
up with an large number of capabilities. Maybe I'm wrong on that,
though.
Cheers,
Andreas.
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2003-02-15 21:29 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2003-02-11 19:18 [PATCH] Extended attribute fixes, etc Andreas Gruenbacher
2003-02-11 20:32 ` Andrew Morton
2003-02-12 11:03 ` Andreas Gruenbacher
2003-02-15 11:07 ` Christoph Hellwig
2003-02-15 17:59 ` Andreas Gruenbacher
2003-02-15 18:39 ` Christoph Hellwig
2003-02-15 19:17 ` Andreas Gruenbacher
2003-02-15 21:09 ` Christoph Hellwig
2003-02-15 21:39 ` Andreas Gruenbacher
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