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-rw-r--r--security/keys/Makefile1
-rw-r--r--security/keys/internal.h14
-rw-r--r--security/keys/key.c23
-rw-r--r--security/keys/keyctl.c12
-rw-r--r--security/keys/proc.c9
-rw-r--r--security/keys/sysctl.c50
6 files changed, 94 insertions, 15 deletions
diff --git a/security/keys/Makefile b/security/keys/Makefile
index 5145adfb6a0..747a464943a 100644
--- a/security/keys/Makefile
+++ b/security/keys/Makefile
@@ -14,3 +14,4 @@ obj-y := \
obj-$(CONFIG_KEYS_COMPAT) += compat.o
obj-$(CONFIG_PROC_FS) += proc.o
+obj-$(CONFIG_SYSCTL) += sysctl.o
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 2ab38854c47..8c05587f501 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -57,10 +57,6 @@ struct key_user {
int qnbytes; /* number of bytes allocated to this user */
};
-#define KEYQUOTA_MAX_KEYS 100
-#define KEYQUOTA_MAX_BYTES 10000
-#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
-
extern struct rb_root key_user_tree;
extern spinlock_t key_user_lock;
extern struct key_user root_key_user;
@@ -68,6 +64,16 @@ extern struct key_user root_key_user;
extern struct key_user *key_user_lookup(uid_t uid);
extern void key_user_put(struct key_user *user);
+/*
+ * key quota limits
+ * - root has its own separate limits to everyone else
+ */
+extern unsigned key_quota_root_maxkeys;
+extern unsigned key_quota_root_maxbytes;
+extern unsigned key_quota_maxkeys;
+extern unsigned key_quota_maxbytes;
+
+#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
extern struct rb_root key_serial_tree;
diff --git a/security/keys/key.c b/security/keys/key.c
index 46f125aa7fa..14948cf83ef 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -27,6 +27,11 @@ DEFINE_SPINLOCK(key_serial_lock);
struct rb_root key_user_tree; /* tree of quota records indexed by UID */
DEFINE_SPINLOCK(key_user_lock);
+unsigned int key_quota_root_maxkeys = 200; /* root's key count quota */
+unsigned int key_quota_root_maxbytes = 20000; /* root's key space quota */
+unsigned int key_quota_maxkeys = 200; /* general key count quota */
+unsigned int key_quota_maxbytes = 20000; /* general key space quota */
+
static LIST_HEAD(key_types_list);
static DECLARE_RWSEM(key_types_sem);
@@ -236,11 +241,16 @@ struct key *key_alloc(struct key_type *type, const char *desc,
/* check that the user's quota permits allocation of another key and
* its description */
if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+ unsigned maxkeys = (uid == 0) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = (uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
spin_lock(&user->lock);
if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
- if (user->qnkeys + 1 >= KEYQUOTA_MAX_KEYS ||
- user->qnbytes + quotalen >= KEYQUOTA_MAX_BYTES
- )
+ if (user->qnkeys + 1 >= maxkeys ||
+ user->qnbytes + quotalen >= maxbytes ||
+ user->qnbytes + quotalen < user->qnbytes)
goto no_quota;
}
@@ -345,11 +355,14 @@ int key_payload_reserve(struct key *key, size_t datalen)
/* contemplate the quota adjustment */
if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ unsigned maxbytes = (key->user->uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
spin_lock(&key->user->lock);
if (delta > 0 &&
- key->user->qnbytes + delta > KEYQUOTA_MAX_BYTES
- ) {
+ (key->user->qnbytes + delta >= maxbytes ||
+ key->user->qnbytes + delta < key->user->qnbytes)) {
ret = -EDQUOT;
}
else {
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 993be634a5e..acc9c89e40a 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -731,10 +731,16 @@ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
/* transfer the quota burden to the new user */
if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ unsigned maxkeys = (uid == 0) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = (uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
spin_lock(&newowner->lock);
- if (newowner->qnkeys + 1 >= KEYQUOTA_MAX_KEYS ||
- newowner->qnbytes + key->quotalen >=
- KEYQUOTA_MAX_BYTES)
+ if (newowner->qnkeys + 1 >= maxkeys ||
+ newowner->qnbytes + key->quotalen >= maxbytes ||
+ newowner->qnbytes + key->quotalen <
+ newowner->qnbytes)
goto quota_overrun;
newowner->qnkeys++;
diff --git a/security/keys/proc.c b/security/keys/proc.c
index e54679b848c..f619170da76 100644
--- a/security/keys/proc.c
+++ b/security/keys/proc.c
@@ -242,6 +242,10 @@ static int proc_key_users_show(struct seq_file *m, void *v)
{
struct rb_node *_p = v;
struct key_user *user = rb_entry(_p, struct key_user, node);
+ unsigned maxkeys = (user->uid == 0) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = (user->uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
user->uid,
@@ -249,10 +253,9 @@ static int proc_key_users_show(struct seq_file *m, void *v)
atomic_read(&user->nkeys),
atomic_read(&user->nikeys),
user->qnkeys,
- KEYQUOTA_MAX_KEYS,
+ maxkeys,
user->qnbytes,
- KEYQUOTA_MAX_BYTES
- );
+ maxbytes);
return 0;
diff --git a/security/keys/sysctl.c b/security/keys/sysctl.c
new file mode 100644
index 00000000000..b611d493c2d
--- /dev/null
+++ b/security/keys/sysctl.c
@@ -0,0 +1,50 @@
+/* Key management controls
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/key.h>
+#include <linux/sysctl.h>
+#include "internal.h"
+
+ctl_table key_sysctls[] = {
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "maxkeys",
+ .data = &key_quota_maxkeys,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "maxbytes",
+ .data = &key_quota_maxbytes,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "root_maxkeys",
+ .data = &key_quota_root_maxkeys,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "root_maxbytes",
+ .data = &key_quota_root_maxbytes,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ { .ctl_name = 0 }
+};
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-23 18:38:51 +0000