From 7e56b5d698707a9934833c47b24d78fb0bcaf764 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 21 Nov 2008 16:45:22 -0800 Subject: [PATCH] net: Fix memory leak in the proto_register function If the slub allocator is used, kmem_cache_create() may merge two or more kmem_cache's into one but the cache name pointer is not updated and kmem_cache_name() is no longer guaranteed to return the pointer passed to the former function. This patch stores the kmalloc'ed pointers in the corresponding request_sock_ops and timewait_sock_ops structures. Signed-off-by: Catalin Marinas Acked-by: Arnaldo Carvalho de Melo Reviewed-by: Christoph Lameter Signed-off-by: David S. Miller --- include/net/request_sock.h | 1 + include/net/timewait_sock.h | 1 + net/core/sock.c | 31 ++++++++++++------------------- 3 files changed, 14 insertions(+), 19 deletions(-) diff --git a/include/net/request_sock.h b/include/net/request_sock.h index cac811e51f6d..c7190846e128 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h @@ -31,6 +31,7 @@ struct request_sock_ops { int family; int obj_size; struct kmem_cache *slab; + char *slab_name; int (*rtx_syn_ack)(struct sock *sk, struct request_sock *req); void (*send_ack)(struct sock *sk, struct sk_buff *skb, diff --git a/include/net/timewait_sock.h b/include/net/timewait_sock.h index 1e1ee3253fd8..97c3b14da55d 100644 --- a/include/net/timewait_sock.h +++ b/include/net/timewait_sock.h @@ -16,6 +16,7 @@ struct timewait_sock_ops { struct kmem_cache *twsk_slab; + char *twsk_slab_name; unsigned int twsk_obj_size; int (*twsk_unique)(struct sock *sk, struct sock *sktw, void *twp); diff --git a/net/core/sock.c b/net/core/sock.c index 341e39456952..edf7220889a4 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2035,9 +2035,6 @@ static inline void release_proto_idx(struct proto *prot) int proto_register(struct proto *prot, int alloc_slab) { - char *request_sock_slab_name = NULL; - char *timewait_sock_slab_name; - if (alloc_slab) { prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, SLAB_HWCACHE_ALIGN, NULL); @@ -2051,12 +2048,12 @@ int proto_register(struct proto *prot, int alloc_slab) if (prot->rsk_prot != NULL) { static const char mask[] = "request_sock_%s"; - request_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL); - if (request_sock_slab_name == NULL) + prot->rsk_prot->slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL); + if (prot->rsk_prot->slab_name == NULL) goto out_free_sock_slab; - sprintf(request_sock_slab_name, mask, prot->name); - prot->rsk_prot->slab = kmem_cache_create(request_sock_slab_name, + sprintf(prot->rsk_prot->slab_name, mask, prot->name); + prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, prot->rsk_prot->obj_size, 0, SLAB_HWCACHE_ALIGN, NULL); @@ -2070,14 +2067,14 @@ int proto_register(struct proto *prot, int alloc_slab) if (prot->twsk_prot != NULL) { static const char mask[] = "tw_sock_%s"; - timewait_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL); + prot->twsk_prot->twsk_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL); - if (timewait_sock_slab_name == NULL) + if (prot->twsk_prot->twsk_slab_name == NULL) goto out_free_request_sock_slab; - sprintf(timewait_sock_slab_name, mask, prot->name); + sprintf(prot->twsk_prot->twsk_slab_name, mask, prot->name); prot->twsk_prot->twsk_slab = - kmem_cache_create(timewait_sock_slab_name, + kmem_cache_create(prot->twsk_prot->twsk_slab_name, prot->twsk_prot->twsk_obj_size, 0, SLAB_HWCACHE_ALIGN, NULL); @@ -2093,14 +2090,14 @@ int proto_register(struct proto *prot, int alloc_slab) return 0; out_free_timewait_sock_slab_name: - kfree(timewait_sock_slab_name); + kfree(prot->twsk_prot->twsk_slab_name); out_free_request_sock_slab: if (prot->rsk_prot && prot->rsk_prot->slab) { kmem_cache_destroy(prot->rsk_prot->slab); prot->rsk_prot->slab = NULL; } out_free_request_sock_slab_name: - kfree(request_sock_slab_name); + kfree(prot->rsk_prot->slab_name); out_free_sock_slab: kmem_cache_destroy(prot->slab); prot->slab = NULL; @@ -2123,18 +2120,14 @@ void proto_unregister(struct proto *prot) } if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { - const char *name = kmem_cache_name(prot->rsk_prot->slab); - kmem_cache_destroy(prot->rsk_prot->slab); - kfree(name); + kfree(prot->rsk_prot->slab_name); prot->rsk_prot->slab = NULL; } if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { - const char *name = kmem_cache_name(prot->twsk_prot->twsk_slab); - kmem_cache_destroy(prot->twsk_prot->twsk_slab); - kfree(name); + kfree(prot->twsk_prot->twsk_slab_name); prot->twsk_prot->twsk_slab = NULL; } }