Both the init_module and finit_module syscalls call either directly or indirectly the security_kernel_read_file LSM hook. This patch replaces the direct call in init_module with a call to the new security_kernel_load_data hook and makes the corresponding changes in SELinux, LoadPin, and IMA.
Signed-off-by: Mimi Zohar <[email protected]> Cc: Jeff Vander Stoep <[email protected]> Cc: Casey Schaufler <[email protected]> Cc: Kees Cook <[email protected]> Acked-by: Jessica Yu <[email protected]> Acked-by: Paul Moore <[email protected]> --- Changelog v6: - LoadPin: add missing cast from enum kernel_load_file_id to kernel_read_file_id. Changelog v5: - For SELinux, have both the security_kernel_read_file and security_kernel_load_data LSM hooks call selinux_kernel_read_file(). - LoadPin: replace existing init_module LSM hook support with new security_kernel_load_data hook. kernel/module.c | 2 +- security/integrity/ima/ima_main.c | 23 ++++++++++------------- security/loadpin/loadpin.c | 6 ++++++ security/selinux/hooks.c | 15 +++++++++++++++ 4 files changed, 32 insertions(+), 14 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index f475f30eed8c..a7615d661910 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2876,7 +2876,7 @@ static int copy_module_from_user(const void __user *umod, unsigned long len, if (info->len < sizeof(*(info->hdr))) return -ENOEXEC; - err = security_kernel_read_file(NULL, READING_MODULE); + err = security_kernel_load_data(LOADING_MODULE); if (err) return err; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index e467664965e7..ef349a761609 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -429,16 +429,6 @@ void ima_post_path_mknod(struct dentry *dentry) */ int ima_read_file(struct file *file, enum kernel_read_file_id read_id) { - bool sig_enforce = is_module_sig_enforced(); - - if (!file && read_id == READING_MODULE) { - if (!sig_enforce && (ima_appraise & IMA_APPRAISE_MODULES) && - (ima_appraise & IMA_APPRAISE_ENFORCE)) { - pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter might help\n"); - return -EACCES; /* INTEGRITY_UNKNOWN */ - } - return 0; /* We rely on module signature checking */ - } return 0; } @@ -479,9 +469,6 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, return 0; } - if (!file && read_id == READING_MODULE) /* MODULE_SIG_FORCE enabled */ - return 0; - /* permit signed certs */ if (!file && read_id == READING_X509_CERTIFICATE) return 0; @@ -510,6 +497,8 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, */ int ima_load_data(enum kernel_load_data_id id) { + bool sig_enforce; + if ((ima_appraise & IMA_APPRAISE_ENFORCE) != IMA_APPRAISE_ENFORCE) return 0; @@ -525,6 +514,14 @@ int ima_load_data(enum kernel_load_data_id id) pr_err("Prevent firmware sysfs fallback loading.\n"); return -EACCES; /* INTEGRITY_UNKNOWN */ } + break; + case LOADING_MODULE: + sig_enforce = is_module_sig_enforced(); + + if (!sig_enforce && (ima_appraise & IMA_APPRAISE_MODULES)) { + pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter might help\n"); + return -EACCES; /* INTEGRITY_UNKNOWN */ + } default: break; } diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c index 5fa191252c8f..0716af28808a 100644 --- a/security/loadpin/loadpin.c +++ b/security/loadpin/loadpin.c @@ -173,9 +173,15 @@ static int loadpin_read_file(struct file *file, enum kernel_read_file_id id) return 0; } +static int loadpin_load_data(enum kernel_load_data_id id) +{ + return loadpin_read_file(NULL, (enum kernel_read_file_id) id); +} + static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security), LSM_HOOK_INIT(kernel_read_file, loadpin_read_file), + LSM_HOOK_INIT(kernel_load_data, loadpin_load_data), }; void __init loadpin_add_hooks(void) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 2b5ee5fbd652..a8bf324130f5 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4073,6 +4073,20 @@ static int selinux_kernel_read_file(struct file *file, return rc; } +static int selinux_kernel_load_data(enum kernel_load_data_id id) +{ + int rc = 0; + + switch (id) { + case LOADING_MODULE: + rc = selinux_kernel_module_from_file(NULL); + default: + break; + } + + return rc; +} + static int selinux_task_setpgid(struct task_struct *p, pid_t pgid) { return avc_has_perm(&selinux_state, @@ -6972,6 +6986,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as), LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as), LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request), + LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data), LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file), LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), -- 2.7.5 _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
