[PATCH 1/3] arch/x86/kernel/cpu/mcheck/mce_amd.c: Avoid leaving freed data in a list

[PATCH 1/3] arch/x86/kernel/cpu/mcheck/mce_amd.c: Avoid leaving freed data in a list

[Julia Lawall]

b may be added to a list, but is not removed before being freed in the case
of an error.  This is done in the corresponding deallocation function, so
the code here has been changed to follow that.

The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E,E1,E2;
identifier l;
@@

*list_add(&E->l,E1);
... when != E1
    when != list_del(&E->l)
    when != list_del_init(&E->l)
    when != E = E2
*kfree(E);// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>

---
 arch/x86/kernel/cpu/mcheck/mce_amd.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 167f97b..bb0adad 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -509,6 +509,7 @@ recurse:
 out_free:
 	if (b) {
 		kobject_put(&b->kobj);
+		list_del(&b->miscj);
 		kfree(b);
 	}
 	return err;

Re: [PATCH 1/3] arch/x86/kernel/cpu/mcheck/mce_amd.c: Avoid leaving freed data in a list

[Borislav Petkov]

On Fri, May 13, 2011 at 09:52:09AM -0400, Julia Lawall wrote:
> b may be added to a list, but is not removed before being freed in the case
> of an error.  This is done in the corresponding deallocation function, so
> the code here has been changed to follow that.
> 
> The sematic match that finds this problem is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@
> expression E,E1,E2;
> identifier l;
> @@
> 
> *list_add(&E->l,E1);
> ... when != E1
>     when != list_del(&E->l)
>     when != list_del_init(&E->l)
>     when != E = E2
> *kfree(E);// </smpl>
> 
> Signed-off-by: Julia Lawall <julia@diku.dk>

Acked-by: Borislav Petkov <borislav.petkov@amd.com>

> 
> ---
>  arch/x86/kernel/cpu/mcheck/mce_amd.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> index 167f97b..bb0adad 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> @@ -509,6 +509,7 @@ recurse:
>  out_free:
>  	if (b) {
>  		kobject_put(&b->kobj);
> +		list_del(&b->miscj);
>  		kfree(b);
>  	}
>  	return err;
> 
> 

-- 
Regards/Gruss,
Boris.

Advanced Micro Devices GmbH
Einsteinring 24, 85609 Dornach
General Managers: Alberto Bozzo, Andrew Bowd
Registration: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632

[tip:x86/urgent] x86, mce, AMD: Fix leaving freed data in a list

[tip-bot for Julia Lawall]

Commit-ID:  d9a5ac9ef306eb5cc874f285185a15c303c50009
Gitweb:     http://git.kernel.org/tip/d9a5ac9ef306eb5cc874f285185a15c303c50009
Author:     Julia Lawall <julia@diku.dk>
AuthorDate: Fri, 13 May 2011 15:52:09 +0200
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 13 May 2011 17:11:02 +0200

x86, mce, AMD: Fix leaving freed data in a list

b may be added to a list, but is not removed before being freed
in the case of an error.  This is done in the corresponding
deallocation function, so the code here has been changed to
follow that.

The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E,E1,E2;
identifier l;
@@

*list_add(&E->l,E1);
... when != E1
    when != list_del(&E->l)
    when != list_del_init(&E->l)
    when != E = E2
*kfree(E);// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1305294731-12127-1-git-send-email-julia@diku.dk
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/kernel/cpu/mcheck/mce_amd.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 167f97b..bb0adad 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -509,6 +509,7 @@ recurse:
 out_free:
 	if (b) {
 		kobject_put(&b->kobj);
+		list_del(&b->miscj);
 		kfree(b);
 	}
 	return err;