diff options
Diffstat (limited to 'mm/secretmem.c')
| -rw-r--r-- | mm/secretmem.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/mm/secretmem.c b/mm/secretmem.c index 1fea68b8d5a6..c2dda408bb36 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -18,7 +18,6 @@ #include <linux/secretmem.h> #include <linux/set_memory.h> #include <linux/sched/signal.h> -#include <linux/refcount.h> #include <uapi/linux/magic.h> @@ -41,11 +40,11 @@ module_param_named(enable, secretmem_enable, bool, 0400); MODULE_PARM_DESC(secretmem_enable, "Enable secretmem and memfd_secret(2) system call"); -static refcount_t secretmem_users; +static atomic_t secretmem_users; bool secretmem_active(void) { - return !!refcount_read(&secretmem_users); + return !!atomic_read(&secretmem_users); } static vm_fault_t secretmem_fault(struct vm_fault *vmf) @@ -104,7 +103,7 @@ static const struct vm_operations_struct secretmem_vm_ops = { static int secretmem_release(struct inode *inode, struct file *file) { - refcount_dec(&secretmem_users); + atomic_dec(&secretmem_users); return 0; } @@ -204,6 +203,8 @@ SYSCALL_DEFINE1(memfd_secret, unsigned int, flags) if (flags & ~(SECRETMEM_FLAGS_MASK | O_CLOEXEC)) return -EINVAL; + if (atomic_read(&secretmem_users) < 0) + return -ENFILE; fd = get_unused_fd_flags(flags & O_CLOEXEC); if (fd < 0) @@ -218,7 +219,7 @@ SYSCALL_DEFINE1(memfd_secret, unsigned int, flags) file->f_flags |= O_LARGEFILE; fd_install(fd, file); - refcount_inc(&secretmem_users); + atomic_inc(&secretmem_users); return fd; err_put_fd: |