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* UML/man: BLKGETSIZE takes a long, not an int
@ 2007-08-13 12:42 Nicolas George
  2007-08-15 17:12 ` Jeff Dike
  0 siblings, 1 reply; 5+ messages in thread
From: Nicolas George @ 2007-08-13 12:42 UTC (permalink / raw)
  To: linux-kernel, uml-devel


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Hi.

I found a type mismatch in UML that makes host block devices unusable as ubd
devices on x86_64 and other 64 bits systems (segfault of the mm subsystem):

In block/ioctl.c, the following lines show that the BLKGETSIZE ioctl expects
a pointer to a long:

	case BLKGETSIZE:
		if ((bdev->bd_inode->i_size >> 9) > ~0UL)
			return -EFBIG;
		return put_ulong(arg, bdev->bd_inode->i_size >> 9);

In arch/um/os-Linux/file.c, os_file_size calls it with an int.

The ioctl_list man page should be fixed as well.

Regards,

-- 
  Nicolas George

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diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index 6f92f73..c3ecc2a 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -320,7 +320,8 @@ int os_file_size(char *file, unsigned long long *size_out)
 	}
 
 	if(S_ISBLK(buf.ust_mode)){
-		int fd, blocks;
+		int fd;
+		long blocks;
 
 		fd = os_open_file(file, of_read(OPENFLAGS()), 0);
 		if(fd < 0){

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^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: UML/man: BLKGETSIZE takes a long, not an int
  2007-08-13 12:42 UML/man: BLKGETSIZE takes a long, not an int Nicolas George
@ 2007-08-15 17:12 ` Jeff Dike
  2007-08-15 21:38   ` [PATCH] UML: " Nicolas George
  0 siblings, 1 reply; 5+ messages in thread
From: Jeff Dike @ 2007-08-15 17:12 UTC (permalink / raw)
  To: Nicolas George; +Cc: linux-kernel, uml-devel

On Mon, Aug 13, 2007 at 02:42:47PM +0200, Nicolas George wrote:
> I found a type mismatch in UML that makes host block devices unusable as ubd
> devices on x86_64 and other 64 bits systems (segfault of the mm subsystem):

Looks sane, can I have a properly Signed-off-by: version of the patch?

				Jeff

-- 
Work email - jdike at linux dot intel dot com

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH] UML: BLKGETSIZE takes a long, not an int
  2007-08-15 17:12 ` Jeff Dike
@ 2007-08-15 21:38   ` Nicolas George
  2007-08-16 14:48     ` Jeff Dike
  0 siblings, 1 reply; 5+ messages in thread
From: Nicolas George @ 2007-08-15 21:38 UTC (permalink / raw)
  To: Jeff Dike; +Cc: linux-kernel, user-mode-linux-devel

The BLKGETSIZE ioctl expects a pointer to a long, os_file_size was providing
an int. Therefore, ubd access to host block devices caused a segmentation
fault on 64 bits systems.

Signed-off-by: Nicolas George <nicolas.george@normalesup.org>

---

Jeff Dike wrote:
> Looks sane, can I have a properly Signed-off-by: version of the patch?

Of course. I should have sent it correctly the first time. And I am terribly
sorry for the mess my mailer have done with my second mail.

Here is the hopefully correct patch, against current git.

Regards.

diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index 6f92f73..c3ecc2a 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -320,7 +320,8 @@ int os_file_size(char *file, unsigned long long *size_out)
 	}
 
 	if(S_ISBLK(buf.ust_mode)){
-		int fd, blocks;
+		int fd;
+		long blocks;
 
 		fd = os_open_file(file, of_read(OPENFLAGS()), 0);
 		if(fd < 0){

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH] UML: BLKGETSIZE takes a long, not an int
  2007-08-15 21:38   ` [PATCH] UML: " Nicolas George
@ 2007-08-16 14:48     ` Jeff Dike
  0 siblings, 0 replies; 5+ messages in thread
From: Jeff Dike @ 2007-08-16 14:48 UTC (permalink / raw)
  To: Nicolas George; +Cc: linux-kernel, user-mode-linux-devel

On Wed, Aug 15, 2007 at 11:38:25PM +0200, Nicolas George wrote:
> Here is the hopefully correct patch, against current git.

Thanks, I'll forward it upstream.

				Jeff

-- 
Work email - jdike at linux dot intel dot com

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: UML/man: BLKGETSIZE takes a long, not an int
  2007-08-14  9:29 Nicolas George
@ 2007-08-27 13:25 ` Michael Kerrisk
  0 siblings, 0 replies; 5+ messages in thread
From: Michael Kerrisk @ 2007-08-27 13:25 UTC (permalink / raw)
  To: Nicolas George; +Cc: linux-kernel, user-mode-linux-devel, jdike

Hello Nicolas,

> I fear that my bug-report yesterday was very badly written, with me writing
> to the wrong mailing-list and all.
> 
> I was saying:
> 
>> I found a type mismatch in UML that makes host block devices unusable as ubd
>> devices on x86_64 and other 64 bits systems (segfault of the mm subsystem):
>>
>> In block/ioctl.c, the following lines show that the BLKGETSIZE ioctl expects
>> a pointer to a long:
>>
>> 	case BLKGETSIZE:
>> 		if ((bdev->bd_inode->i_size >> 9) > ~0UL)
>> 			return -EFBIG;
>> 		return put_ulong(arg, bdev->bd_inode->i_size >> 9);
>>
>> In arch/um/os-Linux/file.c, os_file_size calls it with an int.
>>
>> The ioctl_list man page should be fixed as well.

manual page changed for 2.65:

--- ioctl_list.2
+++ ioctl_list.2        (working copy)
@@ -243,7 +243,7 @@
 0x0000125D  BLKROSET                   const int *
 0x0000125E  BLKROGET                   int *
 0x0000125F  BLKRRPART                  void
-0x00001260  BLKGETSIZE                 int *
+0x00001260  BLKGETSIZE                 unsigned long *
 0x00001261  BLKFLSBUF                  void
 0x00001262  BLKRASET                   int
 0x00001263  BLKRAGET                   int *

Thanks,

Michael

-- 
Michael Kerrisk
maintainer of Linux man pages Sections 2, 3, 4, 5, and 7

Want to help with man page maintenance?  Grab the latest tarball at
http://www.kernel.org/pub/linux/docs/manpages/
read the HOWTOHELP file and grep the source files for 'FIXME'.

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2007-08-27 13:27 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-08-13 12:42 UML/man: BLKGETSIZE takes a long, not an int Nicolas George
2007-08-15 17:12 ` Jeff Dike
2007-08-15 21:38   ` [PATCH] UML: " Nicolas George
2007-08-16 14:48     ` Jeff Dike
2007-08-14  9:29 Nicolas George
2007-08-27 13:25 ` UML/man: BLKGETSIZE takes a long, not an int Michael Kerrisk

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