diff options
| -rw-r--r-- | fs/proc/base.c | 72 | ||||
| -rw-r--r-- | include/linux/prctl.h | 4 | ||||
| -rw-r--r-- | include/linux/seccomp.h | 15 | ||||
| -rw-r--r-- | kernel/seccomp.c | 26 | ||||
| -rw-r--r-- | kernel/sys.c | 8 |
5 files changed, 51 insertions, 74 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index d092194..ae36273 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -67,7 +67,6 @@ #include <linux/mount.h> #include <linux/security.h> #include <linux/ptrace.h> -#include <linux/seccomp.h> #include <linux/cpuset.h> #include <linux/audit.h> #include <linux/poll.h> @@ -817,71 +816,6 @@ static const struct file_operations proc_loginuid_operations = { }; #endif -#ifdef CONFIG_SECCOMP -static ssize_t seccomp_read(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode); - char __buf[20]; - size_t len; - - if (!tsk) - return -ESRCH; - /* no need to print the trailing zero, so use only len */ - len = sprintf(__buf, "%u\n", tsk->seccomp.mode); - put_task_struct(tsk); - - return simple_read_from_buffer(buf, count, ppos, __buf, len); -} - -static ssize_t seccomp_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode); - char __buf[20], *end; - unsigned int seccomp_mode; - ssize_t result; - - result = -ESRCH; - if (!tsk) - goto out_no_task; - - /* can set it only once to be even more secure */ - result = -EPERM; - if (unlikely(tsk->seccomp.mode)) - goto out; - - result = -EFAULT; - memset(__buf, 0, sizeof(__buf)); - count = min(count, sizeof(__buf) - 1); - if (copy_from_user(__buf, buf, count)) - goto out; - - seccomp_mode = simple_strtoul(__buf, &end, 0); - if (*end == '\n') - end++; - result = -EINVAL; - if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { - tsk->seccomp.mode = seccomp_mode; - set_tsk_thread_flag(tsk, TIF_SECCOMP); - } else - goto out; - result = -EIO; - if (unlikely(!(end - __buf))) - goto out; - result = end - __buf; -out: - put_task_struct(tsk); -out_no_task: - return result; -} - -static const struct file_operations proc_seccomp_operations = { - .read = seccomp_read, - .write = seccomp_write, -}; -#endif /* CONFIG_SECCOMP */ - #ifdef CONFIG_FAULT_INJECTION static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, size_t count, loff_t *ppos) @@ -2042,9 +1976,6 @@ static const struct pid_entry tgid_base_stuff[] = { REG("numa_maps", S_IRUGO, numa_maps), #endif REG("mem", S_IRUSR|S_IWUSR, mem), -#ifdef CONFIG_SECCOMP - REG("seccomp", S_IRUSR|S_IWUSR, seccomp), -#endif LNK("cwd", cwd), LNK("root", root), LNK("exe", exe), @@ -2329,9 +2260,6 @@ static const struct pid_entry tid_base_stuff[] = { REG("numa_maps", S_IRUGO, numa_maps), #endif REG("mem", S_IRUSR|S_IWUSR, mem), -#ifdef CONFIG_SECCOMP - REG("seccomp", S_IRUSR|S_IWUSR, seccomp), -#endif LNK("cwd", cwd), LNK("root", root), LNK("exe", exe), diff --git a/include/linux/prctl.h b/include/linux/prctl.h index 52a9be4..e2eff90 100644 --- a/include/linux/prctl.h +++ b/include/linux/prctl.h @@ -59,4 +59,8 @@ # define PR_ENDIAN_LITTLE 1 /* True little endian mode */ # define PR_ENDIAN_PPC_LITTLE 2 /* "PowerPC" pseudo little endian */ +/* Get/set process seccomp mode */ +#define PR_GET_SECCOMP 21 +#define PR_SET_SECCOMP 22 + #endif /* _LINUX_PRCTL_H */ diff --git a/include/linux/seccomp.h b/include/linux/seccomp.h index 3e8b1cf..d708974 100644 --- a/include/linux/seccomp.h +++ b/include/linux/seccomp.h @@ -4,8 +4,6 @@ #ifdef CONFIG_SECCOMP -#define NR_SECCOMP_MODES 1 - #include <linux/thread_info.h> #include <asm/seccomp.h> @@ -23,6 +21,9 @@ static inline int has_secure_computing(struct thread_info *ti) return unlikely(test_ti_thread_flag(ti, TIF_SECCOMP)); } +extern long prctl_get_seccomp(void); +extern long prctl_set_seccomp(unsigned long); + #else /* CONFIG_SECCOMP */ typedef struct { } seccomp_t; @@ -34,6 +35,16 @@ static inline int has_secure_computing(struct thread_info *ti) return 0; } +static inline long prctl_get_seccomp(void) +{ + return -EINVAL; +} + +static inline long prctl_set_seccomp(unsigned long arg2) +{ + return -EINVAL; +} + #endif /* CONFIG_SECCOMP */ #endif /* _LINUX_SECCOMP_H */ diff --git a/kernel/seccomp.c b/kernel/seccomp.c index c3391b6..1dfa8a5 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -10,6 +10,7 @@ #include <linux/sched.h> /* #define SECCOMP_DEBUG 1 */ +#define NR_SECCOMP_MODES 1 /* * Secure computing mode 1 allows only read/write/exit/sigreturn. @@ -54,3 +55,28 @@ void __secure_computing(int this_syscall) #endif do_exit(SIGKILL); } + +long prctl_get_seccomp(void) +{ + return current->seccomp.mode; +} + +long prctl_set_seccomp(unsigned long seccomp_mode) +{ + long ret; + + /* can set it only once to be even more secure */ + ret = -EPERM; + if (unlikely(current->seccomp.mode)) + goto out; + + ret = -EINVAL; + if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { + current->seccomp.mode = seccomp_mode; + set_thread_flag(TIF_SECCOMP); + ret = 0; + } + + out: + return ret; +} diff --git a/kernel/sys.c b/kernel/sys.c index ed92e2f..4d141ae 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -31,6 +31,7 @@ #include <linux/cn_proc.h> #include <linux/getcpu.h> #include <linux/task_io_accounting_ops.h> +#include <linux/seccomp.h> #include <linux/compat.h> #include <linux/syscalls.h> @@ -2242,6 +2243,13 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, error = SET_ENDIAN(current, arg2); break; + case PR_GET_SECCOMP: + error = prctl_get_seccomp(); + break; + case PR_SET_SECCOMP: + error = prctl_set_seccomp(arg2); + break; + default: error = -EINVAL; break; |