[PATCH tip/x86/x32] fs: fix close_on_exec pointer in alloc_fdtable

[PATCH tip/x86/x32] fs: fix close_on_exec pointer in alloc_fdtable

[Bobby Powers]

alloc_fdtable allocates space for the open_fds and close_on_exec
bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
BITS_PER_LONG, as introducted in 1fd36adc: Replace the fd_sets in
struct fdtable with an array of unsigned longs.

Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
---
 fs/file.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/file.c b/fs/file.c
index 2d479dd..171f6b4 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -179,7 +179,7 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
 	if (!data)
 		goto out_arr;
 	fdt->open_fds = data;
-	data += nr / BITS_PER_LONG;
+	data += nr / BITS_PER_BYTE;
 	fdt->close_on_exec = data;
 	fdt->next = NULL;
 
-- 
1.7.7.6

Re: [PATCH tip/x86/x32] fs: fix close_on_exec pointer in alloc_fdtable

[David Howells]

Bobby Powers <bobbypowers@gmail.com> wrote:

> alloc_fdtable allocates space for the open_fds and close_on_exec
> bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
> point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
> BITS_PER_LONG, as introducted in 1fd36adc: Replace the fd_sets in
> struct fdtable with an array of unsigned longs.
> 
> Signed-off-by: Bobby Powers <bobbypowers@gmail.com>

Yes, you're right.  At one point I changed data to be an unsigned long *.

Acked-by: David Howells <dhowells@redhat.com>

Re: [PATCH tip/x86/x32] fs: fix close_on_exec pointer in alloc_fdtable

[Bobby Powers]

On Wed, Feb 22, 2012 at 5:18 AM, David Howells <dhowells@redhat.com> wrote:
> Bobby Powers <bobbypowers@gmail.com> wrote:
>
>> alloc_fdtable allocates space for the open_fds and close_on_exec
>> bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
>> point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
>> BITS_PER_LONG, as introducted in 1fd36adc: Replace the fd_sets in
>> struct fdtable with an array of unsigned longs.
>>
>> Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
>
> Yes, you're right.  At one point I changed data to be an unsigned long *.
>
> Acked-by: David Howells <dhowells@redhat.com>

Thanks, its nice to have confirmation - I'm still pretty new at this.
Can this get pulled onto tip/x86/x32?  Desktop applications like
firefox and chrome don't work reliably without it.

Re: [PATCH tip/x86/x32] fs: fix close_on_exec pointer in alloc_fdtable

[H. Peter Anvin]

On 02/23/2012 06:40 AM, Bobby Powers wrote:
> On Wed, Feb 22, 2012 at 5:18 AM, David Howells<dhowells@redhat.com>  wrote:
>> Bobby Powers<bobbypowers@gmail.com>  wrote:
>>
>>> alloc_fdtable allocates space for the open_fds and close_on_exec
>>> bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
>>> point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
>>> BITS_PER_LONG, as introducted in 1fd36adc: Replace the fd_sets in
>>> struct fdtable with an array of unsigned longs.
>>>
>>> Signed-off-by: Bobby Powers<bobbypowers@gmail.com>
>>
>> Yes, you're right.  At one point I changed data to be an unsigned long *.
>>
>> Acked-by: David Howells<dhowells@redhat.com>
>
> Thanks, its nice to have confirmation - I'm still pretty new at this.
> Can this get pulled onto tip/x86/x32?  Desktop applications like
> firefox and chrome don't work reliably without it.
>

tip:core/types (and the updated core/types needs to be merged into 
x86/x32) but yes.

	-hpa

[tip:core/types] fs: Fix close_on_exec pointer in alloc_fdtable

[tip-bot for Bobby Powers]

Commit-ID:  f044db4cb4bf16893812d35b5fbeaaf3e30c9215
Gitweb:     http://git.kernel.org/tip/f044db4cb4bf16893812d35b5fbeaaf3e30c9215
Author:     Bobby Powers <bobbypowers@gmail.com>
AuthorDate: Wed, 22 Feb 2012 00:29:47 -0500
Committer:  H. Peter Anvin <hpa@zytor.com>
CommitDate: Thu, 23 Feb 2012 18:28:52 -0800

fs: Fix close_on_exec pointer in alloc_fdtable

alloc_fdtable allocates space for the open_fds and close_on_exec
bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
BITS_PER_LONG, as introducted in 1fd36adc: Replace the fd_sets in
struct fdtable with an array of unsigned longs.

Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
Link: http://lkml.kernel.org/r/1329888587-3087-1-git-send-email-bobbypowers@gmail.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
 fs/file.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/file.c b/fs/file.c
index 2d479dd..171f6b4 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -179,7 +179,7 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
 	if (!data)
 		goto out_arr;
 	fdt->open_fds = data;
-	data += nr / BITS_PER_LONG;
+	data += nr / BITS_PER_BYTE;
 	fdt->close_on_exec = data;
 	fdt->next = NULL;