diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 9df7def86c3b..05cac2c2eca1 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -489,48 +489,66 @@ long prctl_get_seccomp(void) } /** - * seccomp_set_mode: internal function for setting seccomp mode - * @seccomp_mode: requested mode to use - * @filter: optional struct sock_fprog for use with SECCOMP_MODE_FILTER - * - * This function may be called repeatedly with a @seccomp_mode of - * SECCOMP_MODE_FILTER to install additional filters. Every filter - * successfully installed will be evaluated (in reverse order) for each system - * call the task makes. + * seccomp_set_mode_strict: internal function for setting strict seccomp * * Once current->seccomp.mode is non-zero, it may not be changed. * * Returns 0 on success or -EINVAL on failure. */ -static long seccomp_set_mode(unsigned long seccomp_mode, char __user *filter) +static long seccomp_set_mode_strict(void) { + const unsigned long seccomp_mode = SECCOMP_MODE_STRICT; long ret = -EINVAL; if (!seccomp_may_assign_mode(seccomp_mode)) goto out; - switch (seccomp_mode) { - case SECCOMP_MODE_STRICT: - ret = 0; #ifdef TIF_NOTSC - disable_TSC(); + disable_TSC(); #endif - break; + seccomp_assign_mode(seccomp_mode); + ret = 0; + +out: + + return ret; +} + #ifdef CONFIG_SECCOMP_FILTER - case SECCOMP_MODE_FILTER: - ret = seccomp_attach_user_filter(filter); - if (ret) - goto out; - break; -#endif - default: +/** + * seccomp_set_mode_filter: internal function for setting seccomp filter + * @filter: struct sock_fprog containing filter + * + * This function may be called repeatedly to install additional filters. + * Every filter successfully installed will be evaluated (in reverse order) + * for each system call the task makes. + * + * Once current->seccomp.mode is non-zero, it may not be changed. + * + * Returns 0 on success or -EINVAL on failure. + */ +static long seccomp_set_mode_filter(char __user *filter) +{ + const unsigned long seccomp_mode = SECCOMP_MODE_FILTER; + long ret = -EINVAL; + + if (!seccomp_may_assign_mode(seccomp_mode)) + goto out; + + ret = seccomp_attach_user_filter(filter); + if (ret) goto out; - } seccomp_assign_mode(seccomp_mode); out: return ret; } +#else +static inline long seccomp_set_mode_filter(char __user *filter) +{ + return -EINVAL; +} +#endif /** * prctl_set_seccomp: configures current->seccomp.mode @@ -541,5 +559,12 @@ out: */ long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter) { - return seccomp_set_mode(seccomp_mode, filter); + switch (seccomp_mode) { + case SECCOMP_MODE_STRICT: + return seccomp_set_mode_strict(); + case SECCOMP_MODE_FILTER: + return seccomp_set_mode_filter(filter); + default: + return -EINVAL; + } }