diff options
Diffstat (limited to 'kernel/seccomp.c')
| -rw-r--r-- | kernel/seccomp.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/kernel/seccomp.c b/kernel/seccomp.c index d7f538847b84..a635ecba6fe2 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -149,7 +149,7 @@ static void populate_seccomp_data(struct seccomp_data *sd) sd->nr = syscall_get_nr(task, regs); sd->arch = syscall_get_arch(); - syscall_get_arguments(task, regs, 0, 6, args); + syscall_get_arguments(task, regs, args); sd->args[0] = args[0]; sd->args[1] = args[1]; sd->args[2] = args[2]; @@ -267,6 +267,7 @@ static u32 seccomp_run_filters(const struct seccomp_data *sd, * All filters in the list are evaluated and the lowest BPF return * value always takes priority (ignoring the DATA). */ + preempt_disable(); for (; f; f = f->prev) { u32 cur_ret = BPF_PROG_RUN(f->prog, sd); @@ -275,6 +276,7 @@ static u32 seccomp_run_filters(const struct seccomp_data *sd, *match = f; } } + preempt_enable(); return ret; } #endif /* CONFIG_SECCOMP_FILTER */ @@ -329,7 +331,7 @@ static int is_ancestor(struct seccomp_filter *parent, * Expects sighand and cred_guard_mutex locks to be held. * * Returns 0 on success, -ve on error, or the pid of a thread which was - * either not in the correct seccomp mode or it did not have an ancestral + * either not in the correct seccomp mode or did not have an ancestral * seccomp filter. */ static inline pid_t seccomp_can_sync_threads(void) @@ -443,8 +445,8 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog) * behavior of privileged children. */ if (!task_no_new_privs(current) && - security_capable_noaudit(current_cred(), current_user_ns(), - CAP_SYS_ADMIN) != 0) + security_capable(current_cred(), current_user_ns(), + CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) != 0) return ERR_PTR(-EACCES); /* Allocate a new seccomp_filter */ @@ -500,7 +502,10 @@ out: * * Caller must be holding current->sighand->siglock lock. * - * Returns 0 on success, -ve on error. + * Returns 0 on success, -ve on error, or + * - in TSYNC mode: the pid of a thread which was either not in the correct + * seccomp mode or did not have an ancestral seccomp filter + * - in NEW_LISTENER mode: the fd of the new listener */ static long seccomp_attach_filter(unsigned int flags, struct seccomp_filter *filter) @@ -976,6 +981,9 @@ static int seccomp_notify_release(struct inode *inode, struct file *file) struct seccomp_filter *filter = file->private_data; struct seccomp_knotif *knotif; + if (!filter) + return 0; + mutex_lock(&filter->notify_lock); /* @@ -1253,6 +1261,16 @@ static long seccomp_set_mode_filter(unsigned int flags, if (flags & ~SECCOMP_FILTER_FLAG_MASK) return -EINVAL; + /* + * In the successful case, NEW_LISTENER returns the new listener fd. + * But in the failure case, TSYNC returns the thread that died. If you + * combine these two flags, there's no way to tell whether something + * succeeded or failed. So, let's disallow this combination. + */ + if ((flags & SECCOMP_FILTER_FLAG_TSYNC) && + (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER)) + return -EINVAL; + /* Prepare the new filter before holding any locks. */ prepared = seccomp_prepare_user_filter(filter); if (IS_ERR(prepared)) @@ -1299,7 +1317,8 @@ out: mutex_unlock(¤t->signal->cred_guard_mutex); out_put_fd: if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { - if (ret < 0) { + if (ret) { + listener_f->private_data = NULL; fput(listener_f); put_unused_fd(listener); } else { |