Commit e148a8f9 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'uaccess.readdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 

Pull uaccess/readdir updates from Al Viro:
 "Finishing the conversion of readdir.c to unsafe_... API.

  This includes the uaccess_{read,write}_begin series by Christophe
  Leroy"

* 'uaccess.readdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  readdir.c: get rid of the last __put_user(), drop now-useless access_ok()
  readdir.c: get compat_filldir() more or less in sync with filldir()
  switch readdir(2) to unsafe_copy_dirent_name()
  drm/i915/gem: Replace user_access_begin by user_write_access_begin
  uaccess: Selectively open read or write user access
  uaccess: Add user_read_access_begin/end and user_write_access_begin/end
parents e0cd9206 5fb15141

drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c

+3 −2
Original line number Diff line number Diff line
@@ -2794,7 +2794,8 @@ i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data, 
		 * And this range already got effectively checked earlier

		 * when we did the "copy_from_user()" above.

		 */

		if (!user_access_begin(user_exec_list, count * sizeof(*user_exec_list)))

		if (!user_write_access_begin(user_exec_list,

					     count * sizeof(*user_exec_list)))

			goto end;



		for (i = 0; i < args->buffer_count; i++) {
@@ -2808,7 +2809,7 @@ i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data, 
					end_user);

		}

end_user:

		user_access_end();

		user_write_access_end();

end:;

	}

fs/readdir.c

+50 −54
Original line number Diff line number Diff line
@@ -157,17 +157,18 @@ static int fillonedir(struct dir_context *ctx, const char *name, int namlen, 
	}

	buf->result++;

	dirent = buf->dirent;

	if (!access_ok(dirent,

	if (!user_write_access_begin(dirent,

			(unsigned long)(dirent->d_name + namlen + 1) -

				(unsigned long)dirent))

		goto efault;

	if (	__put_user(d_ino, &dirent->d_ino) ||

		__put_user(offset, &dirent->d_offset) ||

		__put_user(namlen, &dirent->d_namlen) ||

		__copy_to_user(dirent->d_name, name, namlen) ||

		__put_user(0, dirent->d_name + namlen))

		goto efault;

	unsafe_put_user(d_ino, &dirent->d_ino, efault_end);

	unsafe_put_user(offset, &dirent->d_offset, efault_end);

	unsafe_put_user(namlen, &dirent->d_namlen, efault_end);

	unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end);

	user_write_access_end();

	return 0;

efault_end:

	user_write_access_end();

efault:

	buf->result = -EFAULT;

	return -EFAULT;
@@ -242,7 +243,7 @@ static int filldir(struct dir_context *ctx, const char *name, int namlen, 
		return -EINTR;

	dirent = buf->current_dir;

	prev = (void __user *) dirent - prev_reclen;

	if (!user_access_begin(prev, reclen + prev_reclen))

	if (!user_write_access_begin(prev, reclen + prev_reclen))

		goto efault;



	/* This might be 'dirent->d_off', but if so it will get overwritten */
@@ -251,14 +252,14 @@ static int filldir(struct dir_context *ctx, const char *name, int namlen, 
	unsafe_put_user(reclen, &dirent->d_reclen, efault_end);

	unsafe_put_user(d_type, (char __user *) dirent + reclen - 1, efault_end);

	unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end);

	user_access_end();

	user_write_access_end();



	buf->current_dir = (void __user *)dirent + reclen;

	buf->prev_reclen = reclen;

	buf->count -= reclen;

	return 0;

efault_end:

	user_access_end();

	user_write_access_end();

efault:

	buf->error = -EFAULT;

	return -EFAULT;
@@ -275,9 +276,6 @@ SYSCALL_DEFINE3(getdents, unsigned int, fd, 
	};

	int error;



	if (!access_ok(dirent, count))

		return -EFAULT;



	f = fdget_pos(fd);

	if (!f.file)

		return -EBADF;
@@ -327,7 +325,7 @@ static int filldir64(struct dir_context *ctx, const char *name, int namlen, 
		return -EINTR;

	dirent = buf->current_dir;

	prev = (void __user *)dirent - prev_reclen;

	if (!user_access_begin(prev, reclen + prev_reclen))

	if (!user_write_access_begin(prev, reclen + prev_reclen))

		goto efault;



	/* This might be 'dirent->d_off', but if so it will get overwritten */
@@ -336,7 +334,7 @@ static int filldir64(struct dir_context *ctx, const char *name, int namlen, 
	unsafe_put_user(reclen, &dirent->d_reclen, efault_end);

	unsafe_put_user(d_type, &dirent->d_type, efault_end);

	unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end);

	user_access_end();

	user_write_access_end();



	buf->prev_reclen = reclen;

	buf->current_dir = (void __user *)dirent + reclen;
@@ -344,7 +342,7 @@ static int filldir64(struct dir_context *ctx, const char *name, int namlen, 
	return 0;



efault_end:

	user_access_end();

	user_write_access_end();

efault:

	buf->error = -EFAULT;

	return -EFAULT;
@@ -361,9 +359,6 @@ int ksys_getdents64(unsigned int fd, struct linux_dirent64 __user *dirent, 
	};

	int error;



	if (!access_ok(dirent, count))

		return -EFAULT;



	f = fdget_pos(fd);

	if (!f.file)

		return -EBADF;
@@ -376,7 +371,7 @@ int ksys_getdents64(unsigned int fd, struct linux_dirent64 __user *dirent, 
		typeof(lastdirent->d_off) d_off = buf.ctx.pos;



		lastdirent = (void __user *) buf.current_dir - buf.prev_reclen;

		if (__put_user(d_off, &lastdirent->d_off))

		if (put_user(d_off, &lastdirent->d_off))

			error = -EFAULT;

		else

			error = count - buf.count;
@@ -424,17 +419,18 @@ static int compat_fillonedir(struct dir_context *ctx, const char *name, 
	}

	buf->result++;

	dirent = buf->dirent;

	if (!access_ok(dirent,

	if (!user_write_access_begin(dirent,

			(unsigned long)(dirent->d_name + namlen + 1) -

				(unsigned long)dirent))

		goto efault;

	if (	__put_user(d_ino, &dirent->d_ino) ||

		__put_user(offset, &dirent->d_offset) ||

		__put_user(namlen, &dirent->d_namlen) ||

		__copy_to_user(dirent->d_name, name, namlen) ||

		__put_user(0, dirent->d_name + namlen))

		goto efault;

	unsafe_put_user(d_ino, &dirent->d_ino, efault_end);

	unsafe_put_user(offset, &dirent->d_offset, efault_end);

	unsafe_put_user(namlen, &dirent->d_namlen, efault_end);

	unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end);

	user_write_access_end();

	return 0;

efault_end:

	user_write_access_end();

efault:

	buf->result = -EFAULT;

	return -EFAULT;
@@ -471,7 +467,7 @@ struct compat_linux_dirent { 
struct compat_getdents_callback {

	struct dir_context ctx;

	struct compat_linux_dirent __user *current_dir;

	struct compat_linux_dirent __user *previous;

	int prev_reclen;

	int count;

	int error;

};
@@ -479,13 +475,17 @@ struct compat_getdents_callback { 
static int compat_filldir(struct dir_context *ctx, const char *name, int namlen,

		loff_t offset, u64 ino, unsigned int d_type)

{

	struct compat_linux_dirent __user * dirent;

	struct compat_linux_dirent __user *dirent, *prev;

	struct compat_getdents_callback *buf =

		container_of(ctx, struct compat_getdents_callback, ctx);

	compat_ulong_t d_ino;

	int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) +

		namlen + 2, sizeof(compat_long_t));

	int prev_reclen;



	buf->error = verify_dirent_name(name, namlen);

	if (unlikely(buf->error))

		return buf->error;

	buf->error = -EINVAL;	/* only used if we fail.. */

	if (reclen > buf->count)

		return -EINVAL;
@@ -494,29 +494,27 @@ static int compat_filldir(struct dir_context *ctx, const char *name, int namlen, 
		buf->error = -EOVERFLOW;

		return -EOVERFLOW;

	}

	dirent = buf->previous;

	if (dirent) {

		if (signal_pending(current))

	prev_reclen = buf->prev_reclen;

	if (prev_reclen && signal_pending(current))

		return -EINTR;

		if (__put_user(offset, &dirent->d_off))

			goto efault;

	}

	dirent = buf->current_dir;

	if (__put_user(d_ino, &dirent->d_ino))

		goto efault;

	if (__put_user(reclen, &dirent->d_reclen))

		goto efault;

	if (copy_to_user(dirent->d_name, name, namlen))

		goto efault;

	if (__put_user(0, dirent->d_name + namlen))

		goto efault;

	if (__put_user(d_type, (char  __user *) dirent + reclen - 1))

	prev = (void __user *) dirent - prev_reclen;

	if (!user_write_access_begin(prev, reclen + prev_reclen))

		goto efault;

	buf->previous = dirent;

	dirent = (void __user *)dirent + reclen;

	buf->current_dir = dirent;



	unsafe_put_user(offset, &prev->d_off, efault_end);

	unsafe_put_user(d_ino, &dirent->d_ino, efault_end);

	unsafe_put_user(reclen, &dirent->d_reclen, efault_end);

	unsafe_put_user(d_type, (char __user *) dirent + reclen - 1, efault_end);

	unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end);

	user_write_access_end();



	buf->prev_reclen = reclen;

	buf->current_dir = (void __user *)dirent + reclen;

	buf->count -= reclen;

	return 0;

efault_end:

	user_write_access_end();

efault:

	buf->error = -EFAULT;

	return -EFAULT;
@@ -526,7 +524,6 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, 
		struct compat_linux_dirent __user *, dirent, unsigned int, count)

{

	struct fd f;

	struct compat_linux_dirent __user * lastdirent;

	struct compat_getdents_callback buf = {

		.ctx.actor = compat_filldir,

		.current_dir = dirent,
@@ -534,9 +531,6 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, 
	};

	int error;



	if (!access_ok(dirent, count))

		return -EFAULT;



	f = fdget_pos(fd);

	if (!f.file)

		return -EBADF;
@@ -544,8 +538,10 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, 
	error = iterate_dir(f.file, &buf.ctx);

	if (error >= 0)

		error = buf.error;

	lastdirent = buf.previous;

	if (lastdirent) {

	if (buf.prev_reclen) {

		struct compat_linux_dirent __user * lastdirent;

		lastdirent = (void __user *)buf.current_dir - buf.prev_reclen;



		if (put_user(buf.ctx.pos, &lastdirent->d_off))

			error = -EFAULT;

		else

include/linux/uaccess.h

+8 −0
Original line number Diff line number Diff line
@@ -378,6 +378,14 @@ extern long strnlen_unsafe_user(const void __user *unsafe_addr, long count); 
static inline unsigned long user_access_save(void) { return 0UL; }

static inline void user_access_restore(unsigned long flags) { }

#endif

#ifndef user_write_access_begin

#define user_write_access_begin user_access_begin

#define user_write_access_end user_access_end

#endif

#ifndef user_read_access_begin

#define user_read_access_begin user_access_begin

#define user_read_access_end user_access_end

#endif



#ifdef CONFIG_HARDENED_USERCOPY

void usercopy_warn(const char *name, const char *detail, bool to_user,

kernel/compat.c

+6 −6
Original line number Diff line number Diff line
@@ -199,7 +199,7 @@ long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask, 
	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);

	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);



	if (!user_access_begin(umask, bitmap_size / 8))

	if (!user_read_access_begin(umask, bitmap_size / 8))

		return -EFAULT;



	while (nr_compat_longs > 1) {
@@ -211,11 +211,11 @@ long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask, 
	}

	if (nr_compat_longs)

		unsafe_get_user(*mask, umask++, Efault);

	user_access_end();

	user_read_access_end();

	return 0;



Efault:

	user_access_end();

	user_read_access_end();

	return -EFAULT;

}
@@ -228,7 +228,7 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask, 
	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);

	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);



	if (!user_access_begin(umask, bitmap_size / 8))

	if (!user_write_access_begin(umask, bitmap_size / 8))

		return -EFAULT;



	while (nr_compat_longs > 1) {
@@ -239,10 +239,10 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask, 
	}

	if (nr_compat_longs)

		unsafe_put_user((compat_ulong_t)*mask, umask++, Efault);

	user_access_end();

	user_write_access_end();

	return 0;

Efault:

	user_access_end();

	user_write_access_end();

	return -EFAULT;

}

kernel/exit.c

+6 −6
Original line number Diff line number Diff line
@@ -1558,7 +1558,7 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *, 
	if (!infop)

		return err;



	if (!user_access_begin(infop, sizeof(*infop)))

	if (!user_write_access_begin(infop, sizeof(*infop)))

		return -EFAULT;



	unsafe_put_user(signo, &infop->si_signo, Efault);
@@ -1567,10 +1567,10 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *, 
	unsafe_put_user(info.pid, &infop->si_pid, Efault);

	unsafe_put_user(info.uid, &infop->si_uid, Efault);

	unsafe_put_user(info.status, &infop->si_status, Efault);

	user_access_end();

	user_write_access_end();

	return err;

Efault:

	user_access_end();

	user_write_access_end();

	return -EFAULT;

}
@@ -1685,7 +1685,7 @@ COMPAT_SYSCALL_DEFINE5(waitid, 
	if (!infop)

		return err;



	if (!user_access_begin(infop, sizeof(*infop)))

	if (!user_write_access_begin(infop, sizeof(*infop)))

		return -EFAULT;



	unsafe_put_user(signo, &infop->si_signo, Efault);
@@ -1694,10 +1694,10 @@ COMPAT_SYSCALL_DEFINE5(waitid, 
	unsafe_put_user(info.pid, &infop->si_pid, Efault);

	unsafe_put_user(info.uid, &infop->si_uid, Efault);

	unsafe_put_user(info.status, &infop->si_status, Efault);

	user_access_end();

	user_write_access_end();

	return err;

Efault:

	user_access_end();

	user_write_access_end();

	return -EFAULT;

}

#endif

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