Ocfs2 devel - Jul 2011 - [PATCH] fs/ocfs2/dlm/dlmlock.c: free kmem_cache_zalloc'd data using kmem_cache_free

From: Julia Lawall <julia at diku.dk>

Memory allocated using kmem_cache_zalloc should be freed using
kmem_cache_free, not kfree.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,e,e1,e2;
@@

x = kmem_cache_zalloc(e1,e2)
... when != x = e
?-kfree(x)
+kmem_cache_free(e1,x)
// </smpl>

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

---
 fs/ocfs2/dlm/dlmlock.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -u -p a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c
--- a/fs/ocfs2/dlm/dlmlock.c
+++ b/fs/ocfs2/dlm/dlmlock.c
@@ -440,7 +440,7 @@ struct dlm_lock * dlm_new_lock(int type,
 		/* zero memory only if kernel-allocated */
 		lksb = kzalloc(sizeof(*lksb), GFP_NOFS);
 		if (!lksb) {
-			kfree(lock);
+			kmem_cache_free(dlm_lock_cache, lock);
 			return NULL;
 		}
 		kernel_allocated = 1;

On Sat, Jul 9, 2011 at 7:04 PM, Julia Lawall <julia at diku.dk>
wrote:
> From: Julia Lawall <julia at diku.dk>
>
> Memory allocated using kmem_cache_zalloc should be freed using
> kmem_cache_free, not kfree.
>
> The semantic patch that fixes this problem is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@
> expression x,e,e1,e2;
> @@
>
> x = kmem_cache_zalloc(e1,e2)
> ... when != x = e
> ?-kfree(x)
> +kmem_cache_free(e1,x)
> // </smpl>
>
> Signed-off-by: Julia Lawall <julia at diku.dk>
Reviewed-by: Pekka Enberg <penberg at kernel.org>
> ---
> ?fs/ocfs2/dlm/dlmlock.c | ? ?2 +-
> ?1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff -u -p a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c
> --- a/fs/ocfs2/dlm/dlmlock.c
> +++ b/fs/ocfs2/dlm/dlmlock.c
> @@ -440,7 +440,7 @@ struct dlm_lock * dlm_new_lock(int type,
> ? ? ? ? ? ? ? ?/* zero memory only if kernel-allocated */
> ? ? ? ? ? ? ? ?lksb = kzalloc(sizeof(*lksb), GFP_NOFS);
> ? ? ? ? ? ? ? ?if (!lksb) {
> - ? ? ? ? ? ? ? ? ? ? ? kfree(lock);
> + ? ? ? ? ? ? ? ? ? ? ? kmem_cache_free(dlm_lock_cache, lock);
> ? ? ? ? ? ? ? ? ? ? ? ?return NULL;
> ? ? ? ? ? ? ? ?}
> ? ? ? ? ? ? ? ?kernel_allocated = 1;
>
> --
> To unsubscribe from this list: send the line "unsubscribe
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> the body of a message to majordomo at vger.kernel.org
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>

this patch is now in the fixes branch of ocfs2.git.

On Sat, Jul 09, 2011 at 06:04:39PM +0200, Julia Lawall
wrote:
> From: Julia Lawall <julia at diku.dk>
> 
> Memory allocated using kmem_cache_zalloc should be freed using
> kmem_cache_free, not kfree.
> 
> The semantic patch that fixes this problem is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@
> expression x,e,e1,e2;
> @@
> 
> x = kmem_cache_zalloc(e1,e2)
> ... when != x = e
> ?-kfree(x)
> +kmem_cache_free(e1,x)
> // </smpl>
> 
> Signed-off-by: Julia Lawall <julia at diku.dk>
> 
> ---
>  fs/ocfs2/dlm/dlmlock.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff -u -p a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c
> --- a/fs/ocfs2/dlm/dlmlock.c
> +++ b/fs/ocfs2/dlm/dlmlock.c
> @@ -440,7 +440,7 @@ struct dlm_lock * dlm_new_lock(int type,
>  		/* zero memory only if kernel-allocated */
>  		lksb = kzalloc(sizeof(*lksb), GFP_NOFS);
>  		if (!lksb) {
> -			kfree(lock);
> +			kmem_cache_free(dlm_lock_cache, lock);
>  			return NULL;
>  		}
>  		kernel_allocated = 1;
> 
> --
> To unsubscribe from this list: send the line "unsubscribe
linux-kernel" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
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