diff mbox series

[V4,2/4] xen: irqfd: Use _IOW instead of the internal _IOC() macro

Message ID 599ca6f1b9dd2f0e6247ea37bee3ea6827404b6d.1697439990.git.viresh.kumar@linaro.org
State New
Headers
Series xen: privcmd: Add ioeventfd and fix irqfd support |

Commit Message

Viresh Kumar Oct. 16, 2023, 7:11 a.m. UTC 
  _IOC() an internal helper that we should not use in driver code.  In
particular, we got the data direction wrong here, which breaks a number
of tools, as having "_IOC_NONE" should never be paired with a nonzero
size.

Use _IOW() instead.

Fixes: f8941e6c4c71 ("xen: privcmd: Add support for irqfd")
Reported-by: Arnd Bergmann <arnd@kernel.org>
Closes: https://lore.kernel.org/all/268a2031-63b8-4c7d-b1e5-8ab83ca80b4a@app.fastmail.com/
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 include/uapi/xen/privcmd.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Juergen Gross Oct. 16, 2023, 7:14 a.m. UTC | #1 
On 16.10.23 09:11, Viresh Kumar wrote:
> _IOC() an internal helper that we should not use in driver code.  In
> particular, we got the data direction wrong here, which breaks a number
> of tools, as having "_IOC_NONE" should never be paired with a nonzero
> size.
> 
> Use _IOW() instead.
> 
> Fixes: f8941e6c4c71 ("xen: privcmd: Add support for irqfd")
> Reported-by: Arnd Bergmann <arnd@kernel.org>
> Closes: https://lore.kernel.org/all/268a2031-63b8-4c7d-b1e5-8ab83ca80b4a@app.fastmail.com/
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Juergen Gross <jgross@suse.com>


Juergen
diff mbox series

Patch

diff --git a/include/uapi/xen/privcmd.h b/include/uapi/xen/privcmd.h
index b143fafce84d..e145bca5105c 100644
--- a/include/uapi/xen/privcmd.h
+++ b/include/uapi/xen/privcmd.h
@@ -138,6 +138,6 @@  struct privcmd_irqfd {
 #define IOCTL_PRIVCMD_MMAP_RESOURCE				\
 	_IOC(_IOC_NONE, 'P', 7, sizeof(struct privcmd_mmap_resource))
 #define IOCTL_PRIVCMD_IRQFD					\
-	_IOC(_IOC_NONE, 'P', 8, sizeof(struct privcmd_irqfd))
+	_IOW('P', 8, struct privcmd_irqfd)
 
 #endif /* __LINUX_PUBLIC_PRIVCMD_H__ */