From c9c5d92211883e9ae22394d1f157ab0d3a7ec895 Mon Sep 17 00:00:00 2001 From: Sukadev Bhattiprolu Date: Thu, 18 Oct 2007 23:40:12 -0700 Subject: [PATCH] pid namespaces: create a slab-cache for 'struct pid_namespace' This will help fixing memory leaks due to bad reference counting. Signed-off-by: Sukadev Bhattiprolu Cc: Oleg Nesterov Cc: Sukadev Bhattiprolu Cc: Paul Menage Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/pid.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/pid.c b/kernel/pid.c index f76097c60475..d88b83eb703e 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -40,6 +40,7 @@ static struct hlist_head *pid_hash; static int pidhash_shift; struct pid init_struct_pid = INIT_STRUCT_PID; +static struct kmem_cache *pid_ns_cachep; int pid_max = PID_MAX_DEFAULT; @@ -486,7 +487,7 @@ static struct pid_namespace *create_pid_namespace(int level) struct pid_namespace *ns; int i; - ns = kmalloc(sizeof(struct pid_namespace), GFP_KERNEL); + ns = kmem_cache_alloc(pid_ns_cachep, GFP_KERNEL); if (ns == NULL) goto out; @@ -516,7 +517,7 @@ static struct pid_namespace *create_pid_namespace(int level) out_free_map: kfree(ns->pidmap[0].page); out_free: - kfree(ns); + kmem_cache_free(pid_ns_cachep, ns); out: return ERR_PTR(-ENOMEM); } @@ -527,7 +528,7 @@ static void destroy_pid_namespace(struct pid_namespace *ns) for (i = 0; i < PIDMAP_ENTRIES; i++) kfree(ns->pidmap[i].page); - kfree(ns); + kmem_cache_free(pid_ns_cachep, ns); } struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *old_ns) @@ -601,4 +602,6 @@ void __init pidmap_init(void) init_pid_ns.pid_cachep = create_pid_cachep(1); if (init_pid_ns.pid_cachep == NULL) panic("Can't create pid_1 cachep\n"); + + pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC); } -- GitLab