Re: [PATCH v3 14/22] security: define kernel_read_file hook
On Thu, 2016-02-11 at 08:54 -0800, Casey Schaufler wrote: > On 2/3/2016 11:06 AM, Mimi Zohar wrote: > > The kernel_read_file security hook is called prior to reading the file > > into memory. > > > > Signed-off-by: Mimi Zohar > > Acked-by: Casey Schaufler > > Being able to deny the read prior to performing any > real work makes a lot of sense. Thanks, Casey! Mimi ___ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec
Re: [PATCH v3 14/22] security: define kernel_read_file hook
On 2/3/2016 11:06 AM, Mimi Zohar wrote:
> The kernel_read_file security hook is called prior to reading the file
> into memory.
>
> Signed-off-by: Mimi Zohar
Acked-by: Casey Schaufler
Being able to deny the read prior to performing any
real work makes a lot of sense.
> ---
> fs/exec.c | 4
> include/linux/ima.h | 6 ++
> include/linux/lsm_hooks.h | 8
> include/linux/security.h | 7 +++
> security/integrity/ima/ima_main.c | 16
> security/security.c | 12
> 6 files changed, 53 insertions(+)
>
> diff --git a/fs/exec.c b/fs/exec.c
> index 5629958..1d39c4e 100644
> --- a/fs/exec.c
> +++ b/fs/exec.c
> @@ -842,6 +842,10 @@ int kernel_read_file(struct file *file, void **buf,
> loff_t *size,
> if (!S_ISREG(file_inode(file)->i_mode) || max_size < 0)
> return -EINVAL;
>
> + ret = security_kernel_read_file(file, id);
> + if (ret)
> + return ret;
> +
> i_size = i_size_read(file_inode(file));
> if (max_size > 0 && i_size > max_size)
> return -EFBIG;
> diff --git a/include/linux/ima.h b/include/linux/ima.h
> index 7aea486..6adcaea 100644
> --- a/include/linux/ima.h
> +++ b/include/linux/ima.h
> @@ -19,6 +19,7 @@ extern int ima_file_check(struct file *file, int mask, int
> opened);
> extern void ima_file_free(struct file *file);
> extern int ima_file_mmap(struct file *file, unsigned long prot);
> extern int ima_module_check(struct file *file);
> +extern int ima_read_file(struct file *file, enum kernel_read_file_id id);
> extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
> enum kernel_read_file_id id);
>
> @@ -48,6 +49,11 @@ static inline int ima_module_check(struct file *file)
> return 0;
> }
>
> +static inline int ima_read_file(struct file *file, enum kernel_read_file_id
> id)
> +{
> + return 0;
> +}
> +
> static inline int ima_post_read_file(struct file *file, void *buf, loff_t
> size,
>enum kernel_read_file_id id)
> {
> diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
> index 7d04a12..d32b7bd 100644
> --- a/include/linux/lsm_hooks.h
> +++ b/include/linux/lsm_hooks.h
> @@ -552,6 +552,12 @@
> * the kernel module to load. If the module is being loaded from a blob,
> * this argument will be NULL.
> * Return 0 if permission is granted.
> + * @kernel_read_file:
> + * Read a file specified by userspace.
> + * @file contains the file structure pointing to the file being read
> + * by the kernel.
> + * @id kernel read file identifier
> + * Return 0 if permission is granted.
> * @kernel_post_read_file:
> * Read a file specified by userspace.
> * @file contains the file structure pointing to the file being read
> @@ -1455,6 +1461,7 @@ union security_list_options {
> int (*kernel_create_files_as)(struct cred *new, struct inode *inode);
> int (*kernel_module_request)(char *kmod_name);
> int (*kernel_module_from_file)(struct file *file);
> + int (*kernel_read_file)(struct file *file, enum kernel_read_file_id id);
> int (*kernel_post_read_file)(struct file *file, char *buf, loff_t size,
>enum kernel_read_file_id id);
> int (*task_fix_setuid)(struct cred *new, const struct cred *old,
> @@ -1715,6 +1722,7 @@ struct security_hook_heads {
> struct list_head cred_transfer;
> struct list_head kernel_act_as;
> struct list_head kernel_create_files_as;
> + struct list_head kernel_read_file;
> struct list_head kernel_post_read_file;
> struct list_head kernel_module_request;
> struct list_head kernel_module_from_file;
> diff --git a/include/linux/security.h b/include/linux/security.h
> index cee1349..071fb74 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -302,6 +302,7 @@ int security_kernel_act_as(struct cred *new, u32 secid);
> int security_kernel_create_files_as(struct cred *new, struct inode *inode);
> int security_kernel_module_request(char *kmod_name);
> int security_kernel_module_from_file(struct file *file);
> +int security_kernel_read_file(struct file *file, enum kernel_read_file_id
> id);
> int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
> enum kernel_read_file_id id);
> int security_task_fix_setuid(struct cred *new, const struct cred *old,
> @@ -863,6 +864,12 @@ static inline int
> security_kernel_module_from_file(struct file *file)
> return 0;
> }
>
> +static inline int security_kernel_read_file(struct file *file,
> + enum kernel_read_file_id id)
> +{
> + return 0;
> +}
> +
> static inline int security_kernel_post_read_file(struct file *file,
>char *buf, loff_t size,
>
Re: [PATCH v3 14/22] security: define kernel_read_file hook
On Wed, Feb 03, 2016 at 02:06:22PM -0500, Mimi Zohar wrote: > The kernel_read_file security hook is called prior to reading the file > into memory. > > Signed-off-by: Mimi Zohar Acked-by: Luis R. Rodriguez Luis ___ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec
Re: [PATCH v3 14/22] security: define kernel_read_file hook
On Wed, Feb 3, 2016 at 11:06 AM, Mimi Zohar wrote:
> The kernel_read_file security hook is called prior to reading the file
> into memory.
>
> Signed-off-by: Mimi Zohar
Acked-by: Kees Cook
-Kees
> ---
> fs/exec.c | 4
> include/linux/ima.h | 6 ++
> include/linux/lsm_hooks.h | 8
> include/linux/security.h | 7 +++
> security/integrity/ima/ima_main.c | 16
> security/security.c | 12
> 6 files changed, 53 insertions(+)
>
> diff --git a/fs/exec.c b/fs/exec.c
> index 5629958..1d39c4e 100644
> --- a/fs/exec.c
> +++ b/fs/exec.c
> @@ -842,6 +842,10 @@ int kernel_read_file(struct file *file, void **buf,
> loff_t *size,
> if (!S_ISREG(file_inode(file)->i_mode) || max_size < 0)
> return -EINVAL;
>
> + ret = security_kernel_read_file(file, id);
> + if (ret)
> + return ret;
> +
> i_size = i_size_read(file_inode(file));
> if (max_size > 0 && i_size > max_size)
> return -EFBIG;
> diff --git a/include/linux/ima.h b/include/linux/ima.h
> index 7aea486..6adcaea 100644
> --- a/include/linux/ima.h
> +++ b/include/linux/ima.h
> @@ -19,6 +19,7 @@ extern int ima_file_check(struct file *file, int mask, int
> opened);
> extern void ima_file_free(struct file *file);
> extern int ima_file_mmap(struct file *file, unsigned long prot);
> extern int ima_module_check(struct file *file);
> +extern int ima_read_file(struct file *file, enum kernel_read_file_id id);
> extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
> enum kernel_read_file_id id);
>
> @@ -48,6 +49,11 @@ static inline int ima_module_check(struct file *file)
> return 0;
> }
>
> +static inline int ima_read_file(struct file *file, enum kernel_read_file_id
> id)
> +{
> + return 0;
> +}
> +
> static inline int ima_post_read_file(struct file *file, void *buf, loff_t
> size,
> enum kernel_read_file_id id)
> {
> diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
> index 7d04a12..d32b7bd 100644
> --- a/include/linux/lsm_hooks.h
> +++ b/include/linux/lsm_hooks.h
> @@ -552,6 +552,12 @@
> * the kernel module to load. If the module is being loaded from a blob,
> * this argument will be NULL.
> * Return 0 if permission is granted.
> + * @kernel_read_file:
> + * Read a file specified by userspace.
> + * @file contains the file structure pointing to the file being read
> + * by the kernel.
> + * @id kernel read file identifier
> + * Return 0 if permission is granted.
> * @kernel_post_read_file:
> * Read a file specified by userspace.
> * @file contains the file structure pointing to the file being read
> @@ -1455,6 +1461,7 @@ union security_list_options {
> int (*kernel_create_files_as)(struct cred *new, struct inode *inode);
> int (*kernel_module_request)(char *kmod_name);
> int (*kernel_module_from_file)(struct file *file);
> + int (*kernel_read_file)(struct file *file, enum kernel_read_file_id
> id);
> int (*kernel_post_read_file)(struct file *file, char *buf, loff_t
> size,
> enum kernel_read_file_id id);
> int (*task_fix_setuid)(struct cred *new, const struct cred *old,
> @@ -1715,6 +1722,7 @@ struct security_hook_heads {
> struct list_head cred_transfer;
> struct list_head kernel_act_as;
> struct list_head kernel_create_files_as;
> + struct list_head kernel_read_file;
> struct list_head kernel_post_read_file;
> struct list_head kernel_module_request;
> struct list_head kernel_module_from_file;
> diff --git a/include/linux/security.h b/include/linux/security.h
> index cee1349..071fb74 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -302,6 +302,7 @@ int security_kernel_act_as(struct cred *new, u32 secid);
> int security_kernel_create_files_as(struct cred *new, struct inode *inode);
> int security_kernel_module_request(char *kmod_name);
> int security_kernel_module_from_file(struct file *file);
> +int security_kernel_read_file(struct file *file, enum kernel_read_file_id
> id);
> int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
>enum kernel_read_file_id id);
> int security_task_fix_setuid(struct cred *new, const struct cred *old,
> @@ -863,6 +864,12 @@ static inline int
> security_kernel_module_from_file(struct file *file)
> return 0;
> }
>
> +static inline int security_kernel_read_file(struct file *file,
> + enum kernel_read_file_id id)
> +{
> + return 0;
> +}
> +
> static inline int security_kernel_post_read_file(struct file *file,
> char *buf, loff_t s
[PATCH v3 14/22] security: define kernel_read_file hook
The kernel_read_file security hook is called prior to reading the file
into memory.
Signed-off-by: Mimi Zohar
---
fs/exec.c | 4
include/linux/ima.h | 6 ++
include/linux/lsm_hooks.h | 8
include/linux/security.h | 7 +++
security/integrity/ima/ima_main.c | 16
security/security.c | 12
6 files changed, 53 insertions(+)
diff --git a/fs/exec.c b/fs/exec.c
index 5629958..1d39c4e 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -842,6 +842,10 @@ int kernel_read_file(struct file *file, void **buf, loff_t
*size,
if (!S_ISREG(file_inode(file)->i_mode) || max_size < 0)
return -EINVAL;
+ ret = security_kernel_read_file(file, id);
+ if (ret)
+ return ret;
+
i_size = i_size_read(file_inode(file));
if (max_size > 0 && i_size > max_size)
return -EFBIG;
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 7aea486..6adcaea 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -19,6 +19,7 @@ extern int ima_file_check(struct file *file, int mask, int
opened);
extern void ima_file_free(struct file *file);
extern int ima_file_mmap(struct file *file, unsigned long prot);
extern int ima_module_check(struct file *file);
+extern int ima_read_file(struct file *file, enum kernel_read_file_id id);
extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
enum kernel_read_file_id id);
@@ -48,6 +49,11 @@ static inline int ima_module_check(struct file *file)
return 0;
}
+static inline int ima_read_file(struct file *file, enum kernel_read_file_id id)
+{
+ return 0;
+}
+
static inline int ima_post_read_file(struct file *file, void *buf, loff_t size,
enum kernel_read_file_id id)
{
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 7d04a12..d32b7bd 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -552,6 +552,12 @@
* the kernel module to load. If the module is being loaded from a blob,
* this argument will be NULL.
* Return 0 if permission is granted.
+ * @kernel_read_file:
+ * Read a file specified by userspace.
+ * @file contains the file structure pointing to the file being read
+ * by the kernel.
+ * @id kernel read file identifier
+ * Return 0 if permission is granted.
* @kernel_post_read_file:
* Read a file specified by userspace.
* @file contains the file structure pointing to the file being read
@@ -1455,6 +1461,7 @@ union security_list_options {
int (*kernel_create_files_as)(struct cred *new, struct inode *inode);
int (*kernel_module_request)(char *kmod_name);
int (*kernel_module_from_file)(struct file *file);
+ int (*kernel_read_file)(struct file *file, enum kernel_read_file_id id);
int (*kernel_post_read_file)(struct file *file, char *buf, loff_t size,
enum kernel_read_file_id id);
int (*task_fix_setuid)(struct cred *new, const struct cred *old,
@@ -1715,6 +1722,7 @@ struct security_hook_heads {
struct list_head cred_transfer;
struct list_head kernel_act_as;
struct list_head kernel_create_files_as;
+ struct list_head kernel_read_file;
struct list_head kernel_post_read_file;
struct list_head kernel_module_request;
struct list_head kernel_module_from_file;
diff --git a/include/linux/security.h b/include/linux/security.h
index cee1349..071fb74 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -302,6 +302,7 @@ int security_kernel_act_as(struct cred *new, u32 secid);
int security_kernel_create_files_as(struct cred *new, struct inode *inode);
int security_kernel_module_request(char *kmod_name);
int security_kernel_module_from_file(struct file *file);
+int security_kernel_read_file(struct file *file, enum kernel_read_file_id id);
int security_kernel_post_read_file(struct file *file, char *buf, loff_t size,
enum kernel_read_file_id id);
int security_task_fix_setuid(struct cred *new, const struct cred *old,
@@ -863,6 +864,12 @@ static inline int security_kernel_module_from_file(struct
file *file)
return 0;
}
+static inline int security_kernel_read_file(struct file *file,
+ enum kernel_read_file_id id)
+{
+ return 0;
+}
+
static inline int security_kernel_post_read_file(struct file *file,
char *buf, loff_t size,
enum kernel_read_file_id id)
diff --git a/security/integrity/ima/ima_main.c
b/security/integrity/ima/ima_main.c
index 4a5db31..6f79bdf 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -338,6 +338,22 @@ int ima_modul
