| Message ID | 156096287188.28733.15342608110117616221.stgit@warthog.procyon.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | keys: Namespacing [ver #4] | expand |
On Wed, Jun 19, 2019 at 12:49 PM David Howells <dhowells@redhat.com> wrote: > > Create key domain tags for network namespaces and make it possible to > automatically tag keys that are used by networked services (e.g. AF_RXRPC, > AFS, DNS) with the default network namespace if not set by the caller. > > This allows keys with the same description but in different namespaces to > coexist within a keyring. > > Signed-off-by: David Howells <dhowells@redhat.com> > cc: netdev@vger.kernel.org > cc: linux-nfs@vger.kernel.org > cc: linux-cifs@vger.kernel.org > cc: linux-afs@lists.infradead.org > --- > diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c > index 711b161505ac..076a75c73c9e 100644 > --- a/net/core/net_namespace.c > +++ b/net/core/net_namespace.c > @@ -38,9 +38,16 @@ EXPORT_SYMBOL_GPL(net_namespace_list); > DECLARE_RWSEM(net_rwsem); > EXPORT_SYMBOL_GPL(net_rwsem); > > +#ifdef CONFIG_KEYS > +static struct key_tag init_net_key_domain = { .usage = REFCOUNT_INIT(1) }; > +#endif > + > struct net init_net = { > .count = REFCOUNT_INIT(1), > .dev_base_head = LIST_HEAD_INIT(init_net.dev_base_head), > +#ifdef CONFIG_KEYS > + .key_domain = &init_net_key_domain, > +#endif > }; > EXPORT_SYMBOL(init_net); > > @@ -386,10 +393,21 @@ static struct net *net_alloc(void) > if (!net) > goto out_free; > > +#ifdef CONFIG_KEYS > + net->key_domain = kzalloc(sizeof(struct key_tag), GFP_KERNEL); > + if (!net->key_domain) > + goto out_free_2; > + refcount_set(&net->key_domain->usage, 1); > +#endif > + > rcu_assign_pointer(net->gen, ng); > out: > return net; > > +#ifdef CONFIG_KEYS > +out_free_2: > + kmem_cache_free(net_cachep, net); needs net = NULL; to signal failure > +#endif > out_free: > kfree(ng); > goto out; Reported-by: syzbot <syzkaller@googlegroups.com> BUG: KASAN: use-after-free in atomic_set include/asm-generic/atomic-instrumented.h:44 [inline] BUG: KASAN: use-after-free in refcount_set include/linux/refcount.h:32 [inline] BUG: KASAN: use-after-free in copy_net_ns+0x1e8/0x431 net/core/net_namespace.c:466 Write of size 4 at addr ffff88809c9de080 by task syz-executor.1/12624 CPU: 1 PID: 12624 Comm: syz-executor.1 Not tainted 5.2.0-rc6-next-20190626 #23 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:614 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_write+0x14/0x20 mm/kasan/common.c:100 atomic_set include/asm-generic/atomic-instrumented.h:44 [inline] refcount_set include/linux/refcount.h:32 [inline] copy_net_ns+0x1e8/0x431 net/core/net_namespace.c:466 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202 ksys_unshare+0x444/0x980 kernel/fork.c:2828 __do_sys_unshare kernel/fork.c:2896 [inline] __se_sys_unshare kernel/fork.c:2894 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2894 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459519 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2202261c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f2202261c90 RCX: 0000000000459519 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f22022626d4 R13: 00000000004c8a2c R14: 00000000004df7d0 R15: 0000000000000006 Allocated by task 12624: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:520 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x121/0x710 mm/slab.c:3484 kmem_cache_zalloc include/linux/slab.h:737 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0xf1/0x431 net/core/net_namespace.c:461 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202 ksys_unshare+0x444/0x980 kernel/fork.c:2828 __do_sys_unshare kernel/fork.c:2896 [inline] __se_sys_unshare kernel/fork.c:2894 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2894 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 12624: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x86/0x320 mm/slab.c:3694 net_alloc net/core/net_namespace.c:427 [inline] copy_net_ns+0x3b1/0x431 net/core/net_namespace.c:461 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202 ksys_unshare+0x444/0x980 kernel/fork.c:2828 __do_sys_unshare kernel/fork.c:2896 [inline] __se_sys_unshare kernel/fork.c:2894 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2894 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote: > > +#ifdef CONFIG_KEYS > > +out_free_2: > > + kmem_cache_free(net_cachep, net); > > needs > net = NULL; > > to signal failure > > > +#endif I've folded that into the patch and retagged, remerged and repushed. David
diff --git a/include/linux/key-type.h b/include/linux/key-type.h index e49d1de0614e..2148a6bf58f1 100644 --- a/include/linux/key-type.h +++ b/include/linux/key-type.h @@ -74,6 +74,9 @@ struct key_type { */ size_t def_datalen; + unsigned int flags; +#define KEY_TYPE_NET_DOMAIN 0x00000001 /* Keys of this type have a net namespace domain */ + /* vet a description */ int (*vet_description)(const char *description); diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 12689ddfc24c..a56bf7fc7c2b 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -71,6 +71,9 @@ struct net { */ struct llist_node cleanup_list; /* namespaces on death row */ +#ifdef CONFIG_KEYS + struct key_tag *key_domain; /* Key domain of operation tag */ +#endif struct user_namespace *user_ns; /* Owning user namespace */ struct ucounts *ucounts; spinlock_t nsid_lock; diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 711b161505ac..076a75c73c9e 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -38,9 +38,16 @@ EXPORT_SYMBOL_GPL(net_namespace_list); DECLARE_RWSEM(net_rwsem); EXPORT_SYMBOL_GPL(net_rwsem); +#ifdef CONFIG_KEYS +static struct key_tag init_net_key_domain = { .usage = REFCOUNT_INIT(1) }; +#endif + struct net init_net = { .count = REFCOUNT_INIT(1), .dev_base_head = LIST_HEAD_INIT(init_net.dev_base_head), +#ifdef CONFIG_KEYS + .key_domain = &init_net_key_domain, +#endif }; EXPORT_SYMBOL(init_net); @@ -386,10 +393,21 @@ static struct net *net_alloc(void) if (!net) goto out_free; +#ifdef CONFIG_KEYS + net->key_domain = kzalloc(sizeof(struct key_tag), GFP_KERNEL); + if (!net->key_domain) + goto out_free_2; + refcount_set(&net->key_domain->usage, 1); +#endif + rcu_assign_pointer(net->gen, ng); out: return net; +#ifdef CONFIG_KEYS +out_free_2: + kmem_cache_free(net_cachep, net); +#endif out_free: kfree(ng); goto out; @@ -566,6 +584,7 @@ static void cleanup_net(struct work_struct *work) list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) { list_del_init(&net->exit_list); dec_net_namespaces(net->ucounts); + key_remove_domain(net->key_domain); put_user_ns(net->user_ns); net_drop_ns(net); } diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c index a65d553e730d..3e1a90669006 100644 --- a/net/dns_resolver/dns_key.c +++ b/net/dns_resolver/dns_key.c @@ -314,6 +314,7 @@ static long dns_resolver_read(const struct key *key, struct key_type key_type_dns_resolver = { .name = "dns_resolver", + .flags = KEY_TYPE_NET_DOMAIN, .preparse = dns_resolver_preparse, .free_preparse = dns_resolver_free_preparse, .instantiate = generic_key_instantiate, diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c index e7f6b8823eb6..2722189ec273 100644 --- a/net/rxrpc/key.c +++ b/net/rxrpc/key.c @@ -43,6 +43,7 @@ static long rxrpc_read(const struct key *, char __user *, size_t); */ struct key_type key_type_rxrpc = { .name = "rxrpc", + .flags = KEY_TYPE_NET_DOMAIN, .preparse = rxrpc_preparse, .free_preparse = rxrpc_free_preparse, .instantiate = generic_key_instantiate, @@ -58,6 +59,7 @@ EXPORT_SYMBOL(key_type_rxrpc); */ struct key_type key_type_rxrpc_s = { .name = "rxrpc_s", + .flags = KEY_TYPE_NET_DOMAIN, .vet_description = rxrpc_vet_description_s, .preparse = rxrpc_preparse_s, .free_preparse = rxrpc_free_preparse_s, diff --git a/security/keys/keyring.c b/security/keys/keyring.c index d3c86fda1510..bca070f6ab46 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -17,10 +17,12 @@ #include <linux/seq_file.h> #include <linux/err.h> #include <linux/user_namespace.h> +#include <linux/nsproxy.h> #include <keys/keyring-type.h> #include <keys/user-type.h> #include <linux/assoc_array_priv.h> #include <linux/uaccess.h> +#include <net/net_namespace.h> #include "internal.h" /* @@ -220,7 +222,10 @@ void key_set_index_key(struct keyring_index_key *index_key) memcpy(index_key->desc, index_key->description, n); - index_key->domain_tag = &default_domain_tag; + if (index_key->type->flags & KEY_TYPE_NET_DOMAIN) + index_key->domain_tag = current->nsproxy->net_ns->key_domain; + else + index_key->domain_tag = &default_domain_tag; hash_key_type_and_desc(index_key); }
Create key domain tags for network namespaces and make it possible to automatically tag keys that are used by networked services (e.g. AF_RXRPC, AFS, DNS) with the default network namespace if not set by the caller. This allows keys with the same description but in different namespaces to coexist within a keyring. Signed-off-by: David Howells <dhowells@redhat.com> cc: netdev@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-afs@lists.infradead.org --- include/linux/key-type.h | 3 +++ include/net/net_namespace.h | 3 +++ net/core/net_namespace.c | 19 +++++++++++++++++++ net/dns_resolver/dns_key.c | 1 + net/rxrpc/key.c | 2 ++ security/keys/keyring.c | 7 ++++++- 6 files changed, 34 insertions(+), 1 deletion(-)