diff options
| -rw-r--r-- | fs/fcntl.c | 40 |
1 files changed, 14 insertions, 26 deletions
diff --git a/fs/fcntl.c b/fs/fcntl.c index e632da761fc..3f3ac630ccd 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -55,14 +55,16 @@ static int get_close_on_exec(unsigned int fd) * file_lock held for write. */ -static int locate_fd(struct files_struct *files, - struct file *file, unsigned int orig_start) +static int locate_fd(unsigned int orig_start, int cloexec) { + struct files_struct *files = current->files; unsigned int newfd; unsigned int start; int error; struct fdtable *fdt; + spin_lock(&files->file_lock); + error = -EINVAL; if (orig_start >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) goto out; @@ -97,42 +99,28 @@ repeat: if (error) goto repeat; - /* - * We reacquired files_lock, so we are safe as long as - * we reacquire the fdtable pointer and use it while holding - * the lock, no one can free it during that time. - */ if (start <= files->next_fd) files->next_fd = newfd + 1; + FD_SET(newfd, fdt->open_fds); + if (cloexec) + FD_SET(newfd, fdt->close_on_exec); + else + FD_CLR(newfd, fdt->close_on_exec); error = newfd; - + out: + spin_unlock(&files->file_lock); return error; } static int dupfd(struct file *file, unsigned int start, int cloexec) { - struct files_struct * files = current->files; - struct fdtable *fdt; - int fd; - - spin_lock(&files->file_lock); - fd = locate_fd(files, file, start); - if (fd >= 0) { - /* locate_fd() may have expanded fdtable, load the ptr */ - fdt = files_fdtable(files); - FD_SET(fd, fdt->open_fds); - if (cloexec) - FD_SET(fd, fdt->close_on_exec); - else - FD_CLR(fd, fdt->close_on_exec); - spin_unlock(&files->file_lock); + int fd = locate_fd(start, cloexec); + if (fd >= 0) fd_install(fd, file); - } else { - spin_unlock(&files->file_lock); + else fput(file); - } return fd; } |