Re: [PATCH] tty: Fix TIOCGPTPEER ioctl definition

[Aleksa Sarai]

Sent: 11 July 2017 01:12
This ioctl does nothing to justify an _IOC_READ or _IOC_WRITE flag
because it doesn't copy anything from/to userspace to access the
argument.

Fixes: 54ebbfb1 ("tty: add TIOCGPTPEER ioctl")

...

-#define TIOCGPTPEER_IOR('T', 0x41, int) /* Safely open the slave */
+#define TIOCGPTPEER_IO('T', 0x41) /* Safely open the slave */


This is a user API change. When was the ioctl added?


It was just pulled this merge window (4.13-rc1).

 % git tag --contains 54ebbfb1603415d9953c150535850d30609ef077
 %

--
Aleksa Sarai
Software Engineer (Containers)
SUSE Linux GmbH
https://www.cyphar.com/

RE: [PATCH] tty: Fix TIOCGPTPEER ioctl definition

[David Laight]

From: Linuxppc-dev  Gleb Fotengauer-Malinovskiy
> Sent: 11 July 2017 01:12
> This ioctl does nothing to justify an _IOC_READ or _IOC_WRITE flag
> because it doesn't copy anything from/to userspace to access the
> argument.
> 
> Fixes: 54ebbfb1 ("tty: add TIOCGPTPEER ioctl")
...
> -#define TIOCGPTPEER  _IOR('T', 0x41, int) /* Safely open the slave */
> +#define TIOCGPTPEER  _IO('T', 0x41) /* Safely open the slave */

This is a user API change. When was the ioctl added?

David

Re: [PATCH] tty: Fix TIOCGPTPEER ioctl definition

[James Hogan]

On Tue, Jul 11, 2017 at 03:12:17AM +0300, Gleb Fotengauer-Malinovskiy wrote:
> This ioctl does nothing to justify an _IOC_READ or _IOC_WRITE flag
> because it doesn't copy anything from/to userspace to access the
> argument.
> 
> Fixes: 54ebbfb1 ("tty: add TIOCGPTPEER ioctl")

I think its recommended these days to include at least 12 nibbles of
commit hash, i.e.

Fixes: 54ebbfb16034 ("tty: add TIOCGPTPEER ioctl")

(consider setting your git default to 12 with this):
git config core.abbrev 12

Cheers
James

> Signed-off-by: Gleb Fotengauer-Malinovskiy 
> ---
>  arch/alpha/include/uapi/asm/ioctls.h   | 2 +-
>  arch/mips/include/uapi/asm/ioctls.h| 2 +-
>  arch/parisc/include/uapi/asm/ioctls.h  | 2 +-
>  arch/powerpc/include/uapi/asm/ioctls.h | 2 +-
>  arch/sh/include/uapi/asm/ioctls.h  | 2 +-
>  arch/sparc/include/uapi/asm/ioctls.h   | 2 +-
>  arch/xtensa/include/uapi/asm/ioctls.h  | 2 +-
>  include/uapi/asm-generic/ioctls.h  | 2 +-
>  8 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/alpha/include/uapi/asm/ioctls.h 
> b/arch/alpha/include/uapi/asm/ioctls.h
> index ff67b837..1cd7dc7 100644
> --- a/arch/alpha/include/uapi/asm/ioctls.h
> +++ b/arch/alpha/include/uapi/asm/ioctls.h
> @@ -100,7 +100,7 @@
>  #define TIOCGPKT _IOR('T', 0x38, int) /* Get packet mode state */
>  #define TIOCGPTLCK   _IOR('T', 0x39, int) /* Get Pty lock state */
>  #define TIOCGEXCL_IOR('T', 0x40, int) /* Get exclusive mode state */
> -#define TIOCGPTPEER  _IOR('T', 0x41, int) /* Safely open the slave */
> +#define TIOCGPTPEER  _IO('T', 0x41) /* Safely open the slave */
>  
>  #define TIOCSERCONFIG0x5453
>  #define TIOCSERGWILD 0x5454
> diff --git a/arch/mips/include/uapi/asm/ioctls.h 
> b/arch/mips/include/uapi/asm/ioctls.h
> index 68e19b6..1609cb0 100644
> --- a/arch/mips/include/uapi/asm/ioctls.h
> +++ b/arch/mips/include/uapi/asm/ioctls.h
> @@ -91,7 +91,7 @@
>  #define TIOCGPKT _IOR('T', 0x38, int) /* Get packet mode state */
>  #define TIOCGPTLCK   _IOR('T', 0x39, int) /* Get Pty lock state */
>  #define TIOCGEXCL_IOR('T', 0x40, int) /* Get exclusive mode state */
> -#define TIOCGPTPEER  _IOR('T', 0x41, int) /* Safely open the slave */
> +#define TIOCGPTPEER  _IO('T', 0x41) /* Safely open the slave */
>  
>  /* I hope the range from 0x5480 on is free ... */
>  #define TIOCSCTTY0x5480  /* become controlling tty */
> diff --git a/arch/parisc/include/uapi/asm/ioctls.h 
> b/arch/parisc/include/uapi/asm/ioctls.h
> index 674c68a..d0e3321 100644
> --- a/arch/parisc/include/uapi/asm/ioctls.h
> +++ b/arch/parisc/include/uapi/asm/ioctls.h
> @@ -60,7 +60,7 @@
>  #define TIOCGPKT _IOR('T', 0x38, int) /* Get packet mode state */
>  #define TIOCGPTLCK   _IOR('T', 0x39, int) /* Get Pty lock state */
>  #define TIOCGEXCL_IOR('T', 0x40, int) /* Get exclusive mode state */
> -#define TIOCGPTPEER  _IOR('T', 0x41, int) /* Safely open the slave */
> +#define TIOCGPTPEER  _IO('T', 0x41) /* Safely open the slave */
>  
>  #define FIONCLEX 0x5450  /* these numbers need to be adjusted. */
>  #define FIOCLEX  0x5451
> diff --git a/arch/powerpc/include/uapi/asm/ioctls.h 
> b/arch/powerpc/include/uapi/asm/ioctls.h
> index bfd609a..e3b1046 100644
> --- a/arch/powerpc/include/uapi/asm/ioctls.h
> +++ b/arch/powerpc/include/uapi/asm/ioctls.h
> @@ -100,7 +100,7 @@
>  #define TIOCGPKT _IOR('T', 0x38, int) /* Get packet mode state */
>  #define TIOCGPTLCK   _IOR('T', 0x39, int) /* Get Pty lock state */
>  #define TIOCGEXCL_IOR('T', 0x40, int) /* Get exclusive mode state */
> -#define TIOCGPTPEER  _IOR('T', 0x41, int) /* Safely open the slave */
> +#define TIOCGPTPEER  _IO('T', 0x41) /* Safely open the slave */
>  
>  #define TIOCSERCONFIG0x5453
>  #define TIOCSERGWILD 0x5454
> diff --git a/arch/sh/include/uapi/asm/ioctls.h 
> b/arch/sh/include/uapi/asm/ioctls.h
> index eec7901..787bac9 100644
> --- a/arch/sh/include/uapi/asm/ioctls.h
> +++ b/arch/sh/include/uapi/asm/ioctls.h
> @@ -93,7 +93,7 @@
>  #define TIOCGPKT _IOR('T', 0x38, int) /* Get packet mode state */
>  #define TIOCGPTLCK   _IOR('T', 0x39, int) /* Get Pty lock state */
>  #define TIOCGEXCL_IOR('T', 0x40, int) /* Get exclusive mode state */
> -#define TIOCGPTPEER  _IOR('T', 0x41, int) /* Safely open the slave */
> +#define TIOCGPTPEER  _IO('T', 0x41) /* Safely open the slave */
>  
>  #define TIOCSERCONFIG_IO('T', 83) /* 0x5453 */
>  #define TIOCSERGWILD _IOR('T', 84,  int) /* 0x5454 */
> diff --git a/arch/sparc/include/uapi/asm/ioctls.h 
> b/arch/sparc/include/uapi/asm/ioctls.h
> index 6d27398..f5df72b 100644
> --- a/arch/sparc/include/uapi/asm/ioctls.h
> +++ b/arch/sparc/include/uapi/asm/ioctls.h
> @@ -88,7 +88,7 @@
>  #define TIOCGPTN _IOR('t', 134, unsigned int) /* Get Pty Number */
>  #define TIOCSPTLCK   _IOW('t', 135, int) /* Lock/unlock PTY */
>  #define TIOCSIG  _IOW('t', 136, int) /* Generate signal on Pty 
> slave */
> -#define 

Re: [PATCH] tty: Fix TIOCGPTPEER ioctl definition

[Arnd Bergmann]

On Tue, Jul 11, 2017 at 2:12 AM, Gleb Fotengauer-Malinovskiy
 wrote:
> This ioctl does nothing to justify an _IOC_READ or _IOC_WRITE flag
> because it doesn't copy anything from/to userspace to access the
> argument.
>
> Fixes: 54ebbfb1 ("tty: add TIOCGPTPEER ioctl")
> Signed-off-by: Gleb Fotengauer-Malinovskiy 

Acked-by: Arnd Bergmann 

Re: [PATCH] tty: Fix TIOCGPTPEER ioctl definition

[Aleksa Sarai]

This ioctl does nothing to justify an _IOC_READ or _IOC_WRITE flag
because it doesn't copy anything from/to userspace to access the
argument.


  Acked-by: Aleksa Sarai 

Oops, I misunderstood what _IOR means semantically. TIL -- thanks!

--
Aleksa Sarai
Software Engineer (Containers)
SUSE Linux GmbH
https://www.cyphar.com/