* [PATCH] Btrfs: support security xattr with SELinux enabled
@ 2009-01-07 20:19 jim owens
2009-01-07 20:48 ` Josef Bacik
0 siblings, 1 reply; 4+ messages in thread
From: jim owens @ 2009-01-07 20:19 UTC (permalink / raw)
To: linux-btrfs
Add call to LSM security initialization and save
resulting security xattr for new inodes.
Add xattr support to symlink inode ops.
Set inode->i_op for existing special files.
Signed-off-by: jim owens <jowens@hp.com>
---
fs/btrfs/inode.c | 23 +++++++++++++++++++----
fs/btrfs/xattr.c | 32 ++++++++++++++++++++++++++++++++
fs/btrfs/xattr.h | 2 ++
3 files changed, 53 insertions(+), 4 deletions(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index cdb7011..dd6152a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -91,6 +91,16 @@ static noinline int cow_file_range(struct inode *inode,
u64 start, u64 end, int *page_started,
unsigned long *nr_written, int unlock);
+static int btrfs_init_inode_security(struct inode *inode, struct inode
*dir)
+{
+ int err;
+
+ err = btrfs_init_acl(inode, dir);
+ if (!err)
+ err = btrfs_xattr_security_init(inode, dir);
+ return err;
+}
+
/*
* a very lame attempt at stopping writes when the FS is 85% full. There
* are countless ways this is incorrect, but it is better than nothing.
@@ -2039,6 +2049,7 @@ void btrfs_read_locked_inode(struct inode *inode)
inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
break;
default:
+ inode->i_op = &btrfs_special_inode_operations;
init_special_inode(inode, inode->i_mode, rdev);
break;
}
@@ -3586,7 +3597,7 @@ static int btrfs_mknod(struct inode *dir, struct
dentry *dentry,
if (IS_ERR(inode))
goto out_unlock;
- err = btrfs_init_acl(inode, dir);
+ err = btrfs_init_inode_security(inode, dir);
if (err) {
drop_inode = 1;
goto out_unlock;
@@ -3649,7 +3660,7 @@ static int btrfs_create(struct inode *dir, struct
dentry *dentry,
if (IS_ERR(inode))
goto out_unlock;
- err = btrfs_init_acl(inode, dir);
+ err = btrfs_init_inode_security(inode, dir);
if (err) {
drop_inode = 1;
goto out_unlock;
@@ -3772,7 +3783,7 @@ static int btrfs_mkdir(struct inode *dir, struct
dentry *dentry, int mode)
drop_on_err = 1;
- err = btrfs_init_acl(inode, dir);
+ err = btrfs_init_inode_security(inode, dir);
if (err)
goto out_fail;
@@ -4733,7 +4744,7 @@ static int btrfs_symlink(struct inode *dir, struct
dentry *dentry,
if (IS_ERR(inode))
goto out_unlock;
- err = btrfs_init_acl(inode, dir);
+ err = btrfs_init_inode_security(inode, dir);
if (err) {
drop_inode = 1;
goto out_unlock;
@@ -5032,4 +5043,8 @@ static struct inode_operations
btrfs_symlink_inode_operations = {
.follow_link = page_follow_link_light,
.put_link = page_put_link,
.permission = btrfs_permission,
+ .setxattr = btrfs_setxattr,
+ .getxattr = btrfs_getxattr,
+ .listxattr = btrfs_listxattr,
+ .removexattr = btrfs_removexattr,
};
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index 7f332e2..02195f4 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -21,6 +21,7 @@
#include <linux/slab.h>
#include <linux/rwsem.h>
#include <linux/xattr.h>
+#include <linux/security.h>
#include "ctree.h"
#include "btrfs_inode.h"
#include "transaction.h"
@@ -320,3 +321,34 @@ int btrfs_removexattr(struct dentry *dentry, const
char *name)
return -EOPNOTSUPP;
return __btrfs_setxattr(dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
}
+
+int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
+{
+ int err;
+ size_t len;
+ void *value;
+ char *suffix;
+ char *name;
+
+ err = security_inode_init_security(inode, dir, &suffix, &value, &len);
+ if (err) {
+ if (err == -EOPNOTSUPP)
+ return 0;
+ return err;
+ }
+
+ name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(suffix) + 1,
+ GFP_NOFS);
+ if (!name) {
+ err = -ENOMEM;
+ } else {
+ strcpy(name, XATTR_SECURITY_PREFIX);
+ strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
+ err = __btrfs_setxattr(inode, name, value, len, 0);
+ kfree(name);
+ }
+
+ kfree(suffix);
+ kfree(value);
+ return err;
+}
diff --git a/fs/btrfs/xattr.h b/fs/btrfs/xattr.h
index 5b1d08f..c71e9c3 100644
--- a/fs/btrfs/xattr.h
+++ b/fs/btrfs/xattr.h
@@ -36,4 +36,6 @@ extern int btrfs_setxattr(struct dentry *dentry, const
char *name,
const void *value, size_t size, int flags);
extern int btrfs_removexattr(struct dentry *dentry, const char *name);
+extern int btrfs_xattr_security_init(struct inode *inode, struct inode
*dir);
+
#endif /* __XATTR__ */
--
1.5.4.3
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] Btrfs: support security xattr with SELinux enabled
2009-01-07 20:19 [PATCH] Btrfs: support security xattr with SELinux enabled jim owens
@ 2009-01-07 20:48 ` Josef Bacik
2009-01-08 0:22 ` jim owens
0 siblings, 1 reply; 4+ messages in thread
From: Josef Bacik @ 2009-01-07 20:48 UTC (permalink / raw)
To: jim owens; +Cc: linux-btrfs
On Wed, Jan 07, 2009 at 03:19:38PM -0500, jim owens wrote:
>
> Add call to LSM security initialization and save
> resulting security xattr for new inodes.
>
> Add xattr support to symlink inode ops.
>
> Set inode->i_op for existing special files.
>
> Signed-off-by: jim owens <jowens@hp.com>
> ---
> fs/btrfs/inode.c | 23 +++++++++++++++++++----
> fs/btrfs/xattr.c | 32 ++++++++++++++++++++++++++++++++
> fs/btrfs/xattr.h | 2 ++
> 3 files changed, 53 insertions(+), 4 deletions(-)
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index cdb7011..dd6152a 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -91,6 +91,16 @@ static noinline int cow_file_range(struct inode *inode,
> u64 start, u64 end, int *page_started,
> unsigned long *nr_written, int unlock);
>
> +static int btrfs_init_inode_security(struct inode *inode, struct inode
> *dir)
> +{
> + int err;
> +
> + err = btrfs_init_acl(inode, dir);
> + if (!err)
> + err = btrfs_xattr_security_init(inode, dir);
> + return err;
> +}
> +
> /*
> * a very lame attempt at stopping writes when the FS is 85% full. There
> * are countless ways this is incorrect, but it is better than nothing.
> @@ -2039,6 +2049,7 @@ void btrfs_read_locked_inode(struct inode *inode)
> inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
> break;
> default:
> + inode->i_op = &btrfs_special_inode_operations;
> init_special_inode(inode, inode->i_mode, rdev);
> break;
> }
> @@ -3586,7 +3597,7 @@ static int btrfs_mknod(struct inode *dir, struct
> dentry *dentry,
> if (IS_ERR(inode))
> goto out_unlock;
>
> - err = btrfs_init_acl(inode, dir);
> + err = btrfs_init_inode_security(inode, dir);
> if (err) {
> drop_inode = 1;
> goto out_unlock;
> @@ -3649,7 +3660,7 @@ static int btrfs_create(struct inode *dir, struct
> dentry *dentry,
> if (IS_ERR(inode))
> goto out_unlock;
>
> - err = btrfs_init_acl(inode, dir);
> + err = btrfs_init_inode_security(inode, dir);
> if (err) {
> drop_inode = 1;
> goto out_unlock;
> @@ -3772,7 +3783,7 @@ static int btrfs_mkdir(struct inode *dir, struct
> dentry *dentry, int mode)
>
> drop_on_err = 1;
>
> - err = btrfs_init_acl(inode, dir);
> + err = btrfs_init_inode_security(inode, dir);
> if (err)
> goto out_fail;
>
> @@ -4733,7 +4744,7 @@ static int btrfs_symlink(struct inode *dir, struct
> dentry *dentry,
> if (IS_ERR(inode))
> goto out_unlock;
>
> - err = btrfs_init_acl(inode, dir);
> + err = btrfs_init_inode_security(inode, dir);
> if (err) {
> drop_inode = 1;
> goto out_unlock;
> @@ -5032,4 +5043,8 @@ static struct inode_operations
> btrfs_symlink_inode_operations = {
> .follow_link = page_follow_link_light,
> .put_link = page_put_link,
> .permission = btrfs_permission,
> + .setxattr = btrfs_setxattr,
> + .getxattr = btrfs_getxattr,
> + .listxattr = btrfs_listxattr,
> + .removexattr = btrfs_removexattr,
> };
> diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
> index 7f332e2..02195f4 100644
> --- a/fs/btrfs/xattr.c
> +++ b/fs/btrfs/xattr.c
> @@ -21,6 +21,7 @@
> #include <linux/slab.h>
> #include <linux/rwsem.h>
> #include <linux/xattr.h>
> +#include <linux/security.h>
> #include "ctree.h"
> #include "btrfs_inode.h"
> #include "transaction.h"
> @@ -320,3 +321,34 @@ int btrfs_removexattr(struct dentry *dentry, const
> char *name)
> return -EOPNOTSUPP;
> return __btrfs_setxattr(dentry->d_inode, name, NULL, 0, XATTR_REPLACE);
> }
> +
> +int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
> +{
> + int err;
> + size_t len;
> + void *value;
> + char *suffix;
> + char *name;
> +
> + err = security_inode_init_security(inode, dir, &suffix, &value, &len);
> + if (err) {
> + if (err == -EOPNOTSUPP)
> + return 0;
> + return err;
> + }
> +
> + name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(suffix) + 1,
> + GFP_NOFS);
Use kzalloc here otherwise the end of name could be some random thing and
strlen() will read past the end of the memory. Thanks,
Josef
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] Btrfs: support security xattr with SELinux enabled
2009-01-07 20:48 ` Josef Bacik
@ 2009-01-08 0:22 ` jim owens
2009-01-08 0:47 ` Josef Bacik
0 siblings, 1 reply; 4+ messages in thread
From: jim owens @ 2009-01-08 0:22 UTC (permalink / raw)
To: Josef Bacik; +Cc: linux-btrfs
Josef Bacik wrote:
> On Wed, Jan 07, 2009 at 03:19:38PM -0500, jim owens wrote:
>> +int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
>> +{
>> + int err;
>> + size_t len;
>> + void *value;
>> + char *suffix;
>> + char *name;
>> +
>> + err = security_inode_init_security(inode, dir, &suffix, &value, &len);
>> + if (err) {
>> + if (err == -EOPNOTSUPP)
>> + return 0;
>> + return err;
>> + }
>> +
>> + name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(suffix) + 1,
>> + GFP_NOFS);
>
> Use kzalloc here otherwise the end of name could be some random thing and
> strlen() will read past the end of the memory. Thanks,
I don't understand what you think can happen...
+ strcpy(name, XATTR_SECURITY_PREFIX);
+ strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
always forces "name" to be \0 terminated.
jim
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] Btrfs: support security xattr with SELinux enabled
2009-01-08 0:22 ` jim owens
@ 2009-01-08 0:47 ` Josef Bacik
0 siblings, 0 replies; 4+ messages in thread
From: Josef Bacik @ 2009-01-08 0:47 UTC (permalink / raw)
To: jim owens; +Cc: Josef Bacik, linux-btrfs
On Wed, Jan 07, 2009 at 07:22:58PM -0500, jim owens wrote:
> Josef Bacik wrote:
>> On Wed, Jan 07, 2009 at 03:19:38PM -0500, jim owens wrote:
>>> +int btrfs_xattr_security_init(struct inode *inode, struct inode *dir)
>>> +{
>>> + int err;
>>> + size_t len;
>>> + void *value;
>>> + char *suffix;
>>> + char *name;
>>> +
>>> + err = security_inode_init_security(inode, dir, &suffix, &value, &len);
>>> + if (err) {
>>> + if (err == -EOPNOTSUPP)
>>> + return 0;
>>> + return err;
>>> + }
>>> +
>>> + name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(suffix) + 1,
>>> + GFP_NOFS);
>>
>> Use kzalloc here otherwise the end of name could be some random thing and
>> strlen() will read past the end of the memory. Thanks,
>
> I don't understand what you think can happen...
>
> + strcpy(name, XATTR_SECURITY_PREFIX);
> + strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix);
>
> always forces "name" to be \0 terminated.
>
Oh derr sorry I forget suffix is \0 terminated. Nevermind.
Josef
^ permalink raw reply [flat|nested] 4+ messages in thread
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2009-01-07 20:19 [PATCH] Btrfs: support security xattr with SELinux enabled jim owens
2009-01-07 20:48 ` Josef Bacik
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2009-01-08 0:47 ` Josef Bacik
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