Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753954Ab2HaODw (ORCPT ); Fri, 31 Aug 2012 10:03:52 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:46569 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753918Ab2HaODt (ORCPT ); Fri, 31 Aug 2012 10:03:49 -0400 Date: Fri, 31 Aug 2012 09:03:43 -0500 From: Serge Hallyn To: Kees Cook Cc: linux-kernel@vger.kernel.org, Rusty Russell , James Morris , Al Viro , Eric Paris , Jiri Kosina , linux-security-module@vger.kernel.org Subject: Re: [PATCH 2/2] security: introduce kernel_module_from_file hook Message-ID: <20120831140343.GC24262@amd1> References: <1346275747-8936-1-git-send-email-keescook@chromium.org> <1346275747-8936-2-git-send-email-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1346275747-8936-2-git-send-email-keescook@chromium.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4880 Lines: 131 Quoting Kees Cook (keescook@chromium.org): > Now that kernel module origins can be reasoned about, provide a hook to > the LSMs to make policy decisions about the module file. > > Signed-off-by: Kees Cook Acked-by: Serge E. Hallyn > --- > include/linux/security.h | 11 +++++++++++ > kernel/module.c | 7 +++++++ > security/capability.c | 6 ++++++ > security/security.c | 5 +++++ > 4 files changed, 29 insertions(+), 0 deletions(-) > > diff --git a/include/linux/security.h b/include/linux/security.h > index 3dea6a9..634d09a 100644 > --- a/include/linux/security.h > +++ b/include/linux/security.h > @@ -693,6 +693,10 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) > * userspace to load a kernel module with the given name. > * @kmod_name name of the module requested by the kernel > * Return 0 if successful. > + * @kernel_module_from_file: > + * Load a new kernel module from a file. > + * @file contains the file structure being loaded as a kernel module. > + * Return 0 if permission is granted. > * @task_fix_setuid: > * Update the module's state after setting one or more of the user > * identity attributes of the current process. The @flags parameter > @@ -1507,6 +1511,7 @@ struct security_operations { > int (*kernel_act_as)(struct cred *new, u32 secid); > 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 (*task_fix_setuid) (struct cred *new, const struct cred *old, > int flags); > int (*task_setpgid) (struct task_struct *p, pid_t pgid); > @@ -1764,6 +1769,7 @@ void security_transfer_creds(struct cred *new, const struct cred *old); > 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_task_fix_setuid(struct cred *new, const struct cred *old, > int flags); > int security_task_setpgid(struct task_struct *p, pid_t pgid); > @@ -2277,6 +2283,11 @@ static inline int security_kernel_module_request(char *kmod_name) > return 0; > } > > +static inline int security_kernel_module_from_file(struct file *file) > +{ > + return 0; > +} > + > static inline int security_task_fix_setuid(struct cred *new, > const struct cred *old, > int flags) > diff --git a/kernel/module.c b/kernel/module.c > index 0be8c11..1fcc63f 100644 > --- a/kernel/module.c > +++ b/kernel/module.c > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -2447,6 +2448,12 @@ static Elf_Ehdr *copy_module_from_fd(unsigned int fd, unsigned long *len) > } > size = stat.size; > > + err = security_kernel_module_from_file(file); > + if (err) { > + hdr = ERR_PTR(err); > + goto out; > + } > + > hdr = vmalloc(size); > if (!hdr) { > hdr = ERR_PTR(-ENOMEM); > diff --git a/security/capability.c b/security/capability.c > index 61095df..8acb304 100644 > --- a/security/capability.c > +++ b/security/capability.c > @@ -395,6 +395,11 @@ static int cap_kernel_module_request(char *kmod_name) > return 0; > } > > +static int cap_kernel_module_from_file(struct file *file) > +{ > + return 0; > +} > + > static int cap_task_setpgid(struct task_struct *p, pid_t pgid) > { > return 0; > @@ -967,6 +972,7 @@ void __init security_fixup_ops(struct security_operations *ops) > set_to_cap_if_null(ops, kernel_act_as); > set_to_cap_if_null(ops, kernel_create_files_as); > set_to_cap_if_null(ops, kernel_module_request); > + set_to_cap_if_null(ops, kernel_module_from_file); > set_to_cap_if_null(ops, task_fix_setuid); > set_to_cap_if_null(ops, task_setpgid); > set_to_cap_if_null(ops, task_getpgid); > diff --git a/security/security.c b/security/security.c > index 860aeb3..f7f8695 100644 > --- a/security/security.c > +++ b/security/security.c > @@ -799,6 +799,11 @@ int security_kernel_module_request(char *kmod_name) > return security_ops->kernel_module_request(kmod_name); > } > > +int security_kernel_module_from_file(struct file *file) > +{ > + return security_ops->kernel_module_from_file(file); > +} > + > int security_task_fix_setuid(struct cred *new, const struct cred *old, > int flags) > { > -- > 1.7.0.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/