Pull request: bluetooth-2.6 2010-03-21

Pull request: bluetooth-2.6 2010-03-21

[Marcel Holtmann]

Hi Dave,

these patches fix a potential remote denial of service in the L2CAP
layer and a potential bad memory access with some sysfs files.

As agreed with Linus, I fixed the sysfs issue in two steps. The first
patch just avoids the invalid memory access while accepting that the
content might be truncated. The second patch moves everything over to
debugfs (where these files belong anyway) and switches to seq_file.

This two step approach allows an easy backport to -stable kernel by
only picking the first patch.

Linus, feel free to pull directly since both patches are security
related and should be merged as quickly as possible.

Regards

Marcel


Please pull from

    git://git.kernel.org/pub/scm/linux/kernel/git/holtmann/bluetooth-2.6.git master

This will update the following files:

 include/net/bluetooth/bluetooth.h |    2 +-
 net/bluetooth/hci_sysfs.c         |    3 +-
 net/bluetooth/l2cap.c             |   48 +++++++++++++++++++++++++++----------
 net/bluetooth/rfcomm/core.c       |   41 ++++++++++++++++++++++---------
 net/bluetooth/rfcomm/sock.c       |   38 ++++++++++++++++++++--------
 net/bluetooth/sco.c               |   38 ++++++++++++++++++++---------
 6 files changed, 119 insertions(+), 51 deletions(-)

through these ChangeSets:

Andrei Emeltchenko (1):
    Bluetooth: Fix kernel crash on L2CAP stress tests

Marcel Holtmann (2):
    Bluetooth: Fix potential bad memory access with sysfs files
    Bluetooth: Convert debug files to actually use debugfs instead of sysfs

[PATCH 1/3] Bluetooth: Fix potential bad memory access with sysfs files

[Marcel Holtmann]

When creating a high number of Bluetooth sockets (L2CAP, SCO
and RFCOMM) it is possible to scribble repeatedly on arbitrary
pages of memory. Ensure that the content of these sysfs files is
always less than one page. Even if this means truncating. The
files in question are scheduled to be moved over to debugfs in
the future anyway.

Based on initial patches from Neil Brown and Linus Torvalds

Reported-by: Neil Brown <neilb@suse.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
---
 net/bluetooth/l2cap.c       |   10 +++++++++-
 net/bluetooth/rfcomm/core.c |   13 ++++++++++++-
 net/bluetooth/rfcomm/sock.c |   11 ++++++++++-
 net/bluetooth/sco.c         |   11 ++++++++++-
 4 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 4db7ae2..2755182 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -3944,16 +3944,24 @@ static ssize_t l2cap_sysfs_show(struct class *dev,
 	struct sock *sk;
 	struct hlist_node *node;
 	char *str = buf;
+	int size = PAGE_SIZE;
 
 	read_lock_bh(&l2cap_sk_list.lock);
 
 	sk_for_each(sk, node, &l2cap_sk_list.head) {
 		struct l2cap_pinfo *pi = l2cap_pi(sk);
+		int len;
 
-		str += sprintf(str, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d\n",
+		len = snprintf(str, size, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d\n",
 				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
 				sk->sk_state, __le16_to_cpu(pi->psm), pi->scid,
 				pi->dcid, pi->imtu, pi->omtu, pi->sec_level);
+
+		size -= len;
+		if (size <= 0)
+			break;
+
+		str += len;
 	}
 
 	read_unlock_bh(&l2cap_sk_list.lock);
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index db8a68e..cf16407 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -2105,6 +2105,7 @@ static ssize_t rfcomm_dlc_sysfs_show(struct class *dev,
 	struct rfcomm_session *s;
 	struct list_head *pp, *p;
 	char *str = buf;
+	int size = PAGE_SIZE;
 
 	rfcomm_lock();
 
@@ -2113,11 +2114,21 @@ static ssize_t rfcomm_dlc_sysfs_show(struct class *dev,
 		list_for_each(pp, &s->dlcs) {
 			struct sock *sk = s->sock->sk;
 			struct rfcomm_dlc *d = list_entry(pp, struct rfcomm_dlc, list);
+			int len;
 
-			str += sprintf(str, "%s %s %ld %d %d %d %d\n",
+			len = snprintf(str, size, "%s %s %ld %d %d %d %d\n",
 					batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
 					d->state, d->dlci, d->mtu, d->rx_credits, d->tx_credits);
+
+			size -= len;
+			if (size <= 0)
+				break;
+
+			str += len;
 		}
+
+		if (size <= 0)
+			break;
 	}
 
 	rfcomm_unlock();
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index ca87d6a..8d0ee0b 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -1068,13 +1068,22 @@ static ssize_t rfcomm_sock_sysfs_show(struct class *dev,
 	struct sock *sk;
 	struct hlist_node *node;
 	char *str = buf;
+	int size = PAGE_SIZE;
 
 	read_lock_bh(&rfcomm_sk_list.lock);
 
 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
-		str += sprintf(str, "%s %s %d %d\n",
+		int len;
+
+		len = snprintf(str, size, "%s %s %d %d\n",
 				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
 				sk->sk_state, rfcomm_pi(sk)->channel);
+
+		size -= len;
+		if (size <= 0)
+			break;
+
+		str += len;
 	}
 
 	read_unlock_bh(&rfcomm_sk_list.lock);
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index f93b939..967a751 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -960,13 +960,22 @@ static ssize_t sco_sysfs_show(struct class *dev,
 	struct sock *sk;
 	struct hlist_node *node;
 	char *str = buf;
+	int size = PAGE_SIZE;
 
 	read_lock_bh(&sco_sk_list.lock);
 
 	sk_for_each(sk, node, &sco_sk_list.head) {
-		str += sprintf(str, "%s %s %d\n",
+		int len;
+
+		len = snprintf(str, size, "%s %s %d\n",
 				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
 				sk->sk_state);
+
+		size -= len;
+		if (size <= 0)
+			break;
+
+		str += len;
 	}
 
 	read_unlock_bh(&sco_sk_list.lock);
-- 
1.6.6.1

[PATCH 2/3] Bluetooth: Convert debug files to actually use debugfs instead of sysfs

[Marcel Holtmann]

Some of the debug files ended up wrongly in sysfs, because at that point
of time, debugfs didn't exist. Convert these files to use debugfs and
also seq_file. This patch converts all of these files at once and then
removes the exported symbol for the Bluetooth sysfs class.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
---
 include/net/bluetooth/bluetooth.h |    2 +-
 net/bluetooth/hci_sysfs.c         |    3 +-
 net/bluetooth/l2cap.c             |   51 +++++++++++++++++++++---------------
 net/bluetooth/rfcomm/core.c       |   52 ++++++++++++++++++++----------------
 net/bluetooth/rfcomm/sock.c       |   47 +++++++++++++++++++--------------
 net/bluetooth/sco.c               |   47 ++++++++++++++++++---------------
 6 files changed, 114 insertions(+), 88 deletions(-)

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 04a6908..ff77e8f 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -176,6 +176,6 @@ extern void hci_sock_cleanup(void);
 extern int bt_sysfs_init(void);
 extern void bt_sysfs_cleanup(void);
 
-extern struct class *bt_class;
+extern struct dentry *bt_debugfs;
 
 #endif /* __BLUETOOTH_H */
diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index cafb55b..05fd125 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/net/bluetooth/hci_sysfs.c
@@ -8,8 +8,7 @@
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
 
-struct class *bt_class = NULL;
-EXPORT_SYMBOL_GPL(bt_class);
+static struct class *bt_class;
 
 struct dentry *bt_debugfs = NULL;
 EXPORT_SYMBOL_GPL(bt_debugfs);
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 2755182..43e17f7 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -40,6 +40,8 @@
 #include <linux/skbuff.h>
 #include <linux/list.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <linux/uaccess.h>
 #include <linux/crc16.h>
 #include <net/sock.h>
@@ -3937,39 +3939,42 @@ drop:
 	return 0;
 }
 
-static ssize_t l2cap_sysfs_show(struct class *dev,
-				struct class_attribute *attr,
-				char *buf)
+static int l2cap_debugfs_show(struct seq_file *f, void *p)
 {
 	struct sock *sk;
 	struct hlist_node *node;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	read_lock_bh(&l2cap_sk_list.lock);
 
 	sk_for_each(sk, node, &l2cap_sk_list.head) {
 		struct l2cap_pinfo *pi = l2cap_pi(sk);
-		int len;
-
-		len = snprintf(str, size, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d\n",
-				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
-				sk->sk_state, __le16_to_cpu(pi->psm), pi->scid,
-				pi->dcid, pi->imtu, pi->omtu, pi->sec_level);
-
-		size -= len;
-		if (size <= 0)
-			break;
 
-		str += len;
+		seq_printf(f, "%s %s %d %d 0x%4.4x 0x%4.4x %d %d %d\n",
+					batostr(&bt_sk(sk)->src),
+					batostr(&bt_sk(sk)->dst),
+					sk->sk_state, __le16_to_cpu(pi->psm),
+					pi->scid, pi->dcid,
+					pi->imtu, pi->omtu, pi->sec_level);
 	}
 
 	read_unlock_bh(&l2cap_sk_list.lock);
 
-	return str - buf;
+	return 0;
 }
 
-static CLASS_ATTR(l2cap, S_IRUGO, l2cap_sysfs_show, NULL);
+static int l2cap_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, l2cap_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations l2cap_debugfs_fops = {
+	.open		= l2cap_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *l2cap_debugfs;
 
 static const struct proto_ops l2cap_sock_ops = {
 	.family		= PF_BLUETOOTH,
@@ -4029,8 +4034,12 @@ static int __init l2cap_init(void)
 		goto error;
 	}
 
-	if (class_create_file(bt_class, &class_attr_l2cap) < 0)
-		BT_ERR("Failed to create L2CAP info file");
+	if (bt_debugfs) {
+		l2cap_debugfs = debugfs_create_file("l2cap", 0444,
+					bt_debugfs, NULL, &l2cap_debugfs_fops);
+		if (!l2cap_debugfs)
+			BT_ERR("Failed to create L2CAP debug file");
+	}
 
 	BT_INFO("L2CAP ver %s", VERSION);
 	BT_INFO("L2CAP socket layer initialized");
@@ -4044,7 +4053,7 @@ error:
 
 static void __exit l2cap_exit(void)
 {
-	class_remove_file(bt_class, &class_attr_l2cap);
+	debugfs_remove(l2cap_debugfs);
 
 	if (bt_sock_unregister(BTPROTO_L2CAP) < 0)
 		BT_ERR("L2CAP socket unregistration failed");
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index cf16407..13f114e 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -33,6 +33,8 @@
 #include <linux/init.h>
 #include <linux/wait.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <linux/net.h>
 #include <linux/mutex.h>
 #include <linux/kthread.h>
@@ -2098,14 +2100,10 @@ static struct hci_cb rfcomm_cb = {
 	.security_cfm	= rfcomm_security_cfm
 };
 
-static ssize_t rfcomm_dlc_sysfs_show(struct class *dev,
-				     struct class_attribute *attr,
-				     char *buf)
+static int rfcomm_dlc_debugfs_show(struct seq_file *f, void *x)
 {
 	struct rfcomm_session *s;
 	struct list_head *pp, *p;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	rfcomm_lock();
 
@@ -2114,29 +2112,33 @@ static ssize_t rfcomm_dlc_sysfs_show(struct class *dev,
 		list_for_each(pp, &s->dlcs) {
 			struct sock *sk = s->sock->sk;
 			struct rfcomm_dlc *d = list_entry(pp, struct rfcomm_dlc, list);
-			int len;
 
-			len = snprintf(str, size, "%s %s %ld %d %d %d %d\n",
-					batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
-					d->state, d->dlci, d->mtu, d->rx_credits, d->tx_credits);
-
-			size -= len;
-			if (size <= 0)
-				break;
-
-			str += len;
+			seq_printf(f, "%s %s %ld %d %d %d %d\n",
+						batostr(&bt_sk(sk)->src),
+						batostr(&bt_sk(sk)->dst),
+						d->state, d->dlci, d->mtu,
+						d->rx_credits, d->tx_credits);
 		}
-
-		if (size <= 0)
-			break;
 	}
 
 	rfcomm_unlock();
 
-	return (str - buf);
+	return 0;
+}
+
+static int rfcomm_dlc_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, rfcomm_dlc_debugfs_show, inode->i_private);
 }
 
-static CLASS_ATTR(rfcomm_dlc, S_IRUGO, rfcomm_dlc_sysfs_show, NULL);
+static const struct file_operations rfcomm_dlc_debugfs_fops = {
+	.open		= rfcomm_dlc_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *rfcomm_dlc_debugfs;
 
 /* ---- Initialization ---- */
 static int __init rfcomm_init(void)
@@ -2153,8 +2155,12 @@ static int __init rfcomm_init(void)
 		goto unregister;
 	}
 
-	if (class_create_file(bt_class, &class_attr_rfcomm_dlc) < 0)
-		BT_ERR("Failed to create RFCOMM info file");
+	if (bt_debugfs) {
+		rfcomm_dlc_debugfs = debugfs_create_file("rfcomm_dlc", 0444,
+				bt_debugfs, NULL, &rfcomm_dlc_debugfs_fops);
+		if (!rfcomm_dlc_debugfs)
+			BT_ERR("Failed to create RFCOMM debug file");
+	}
 
 	err = rfcomm_init_ttys();
 	if (err < 0)
@@ -2182,7 +2188,7 @@ unregister:
 
 static void __exit rfcomm_exit(void)
 {
-	class_remove_file(bt_class, &class_attr_rfcomm_dlc);
+	debugfs_remove(rfcomm_dlc_debugfs);
 
 	hci_unregister_cb(&rfcomm_cb);
 
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 8d0ee0b..7f43976 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -40,6 +40,8 @@
 #include <linux/skbuff.h>
 #include <linux/list.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <net/sock.h>
 
 #include <asm/system.h>
@@ -1061,37 +1063,38 @@ done:
 	return result;
 }
 
-static ssize_t rfcomm_sock_sysfs_show(struct class *dev,
-				      struct class_attribute *attr,
-				      char *buf)
+static int rfcomm_sock_debugfs_show(struct seq_file *f, void *p)
 {
 	struct sock *sk;
 	struct hlist_node *node;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	read_lock_bh(&rfcomm_sk_list.lock);
 
 	sk_for_each(sk, node, &rfcomm_sk_list.head) {
-		int len;
-
-		len = snprintf(str, size, "%s %s %d %d\n",
-				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
+		seq_printf(f, "%s %s %d %d\n",
+				batostr(&bt_sk(sk)->src),
+				batostr(&bt_sk(sk)->dst),
 				sk->sk_state, rfcomm_pi(sk)->channel);
-
-		size -= len;
-		if (size <= 0)
-			break;
-
-		str += len;
 	}
 
 	read_unlock_bh(&rfcomm_sk_list.lock);
 
-	return (str - buf);
+	return 0;
 }
 
-static CLASS_ATTR(rfcomm, S_IRUGO, rfcomm_sock_sysfs_show, NULL);
+static int rfcomm_sock_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, rfcomm_sock_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations rfcomm_sock_debugfs_fops = {
+	.open		= rfcomm_sock_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *rfcomm_sock_debugfs;
 
 static const struct proto_ops rfcomm_sock_ops = {
 	.family		= PF_BLUETOOTH,
@@ -1131,8 +1134,12 @@ int __init rfcomm_init_sockets(void)
 	if (err < 0)
 		goto error;
 
-	if (class_create_file(bt_class, &class_attr_rfcomm) < 0)
-		BT_ERR("Failed to create RFCOMM info file");
+	if (bt_debugfs) {
+		rfcomm_sock_debugfs = debugfs_create_file("rfcomm", 0444,
+				bt_debugfs, NULL, &rfcomm_sock_debugfs_fops);
+		if (!rfcomm_sock_debugfs)
+			BT_ERR("Failed to create RFCOMM debug file");
+	}
 
 	BT_INFO("RFCOMM socket layer initialized");
 
@@ -1146,7 +1153,7 @@ error:
 
 void rfcomm_cleanup_sockets(void)
 {
-	class_remove_file(bt_class, &class_attr_rfcomm);
+	debugfs_remove(rfcomm_sock_debugfs);
 
 	if (bt_sock_unregister(BTPROTO_RFCOMM) < 0)
 		BT_ERR("RFCOMM socket layer unregistration failed");
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index 967a751..e5b16b7 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -38,6 +38,8 @@
 #include <linux/socket.h>
 #include <linux/skbuff.h>
 #include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <linux/list.h>
 #include <net/sock.h>
 
@@ -953,37 +955,36 @@ drop:
 	return 0;
 }
 
-static ssize_t sco_sysfs_show(struct class *dev,
-				struct class_attribute *attr,
-				char *buf)
+static int sco_debugfs_show(struct seq_file *f, void *p)
 {
 	struct sock *sk;
 	struct hlist_node *node;
-	char *str = buf;
-	int size = PAGE_SIZE;
 
 	read_lock_bh(&sco_sk_list.lock);
 
 	sk_for_each(sk, node, &sco_sk_list.head) {
-		int len;
-
-		len = snprintf(str, size, "%s %s %d\n",
-				batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst),
-				sk->sk_state);
-
-		size -= len;
-		if (size <= 0)
-			break;
-
-		str += len;
+		seq_printf(f, "%s %s %d\n", batostr(&bt_sk(sk)->src),
+				batostr(&bt_sk(sk)->dst), sk->sk_state);
 	}
 
 	read_unlock_bh(&sco_sk_list.lock);
 
-	return (str - buf);
+	return 0;
 }
 
-static CLASS_ATTR(sco, S_IRUGO, sco_sysfs_show, NULL);
+static int sco_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, sco_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations sco_debugfs_fops = {
+	.open		= sco_debugfs_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static struct dentry *sco_debugfs;
 
 static const struct proto_ops sco_sock_ops = {
 	.family		= PF_BLUETOOTH,
@@ -1041,8 +1042,12 @@ static int __init sco_init(void)
 		goto error;
 	}
 
-	if (class_create_file(bt_class, &class_attr_sco) < 0)
-		BT_ERR("Failed to create SCO info file");
+	if (bt_debugfs) {
+		sco_debugfs = debugfs_create_file("sco", 0444,
+					bt_debugfs, NULL, &sco_debugfs_fops);
+		if (!sco_debugfs)
+			BT_ERR("Failed to create SCO debug file");
+	}
 
 	BT_INFO("SCO (Voice Link) ver %s", VERSION);
 	BT_INFO("SCO socket layer initialized");
@@ -1056,7 +1061,7 @@ error:
 
 static void __exit sco_exit(void)
 {
-	class_remove_file(bt_class, &class_attr_sco);
+	debugfs_remove(sco_debugfs);
 
 	if (bt_sock_unregister(BTPROTO_SCO) < 0)
 		BT_ERR("SCO socket unregistration failed");
-- 
1.6.6.1

[PATCH 3/3] Bluetooth: Fix kernel crash on L2CAP stress tests

[Marcel Holtmann]

From: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>

Added very simple check that req buffer has enough space to
fit configuration parameters. Shall be enough to reject packets
with configuration size more than req buffer.

Crash trace below

[ 6069.659393] Unable to handle kernel paging request at virtual address 02000205
[ 6069.673034] Internal error: Oops: 805 [#1] PREEMPT
...
[ 6069.727172] PC is at l2cap_add_conf_opt+0x70/0xf0 [l2cap]
[ 6069.732604] LR is at l2cap_recv_frame+0x1350/0x2e78 [l2cap]
...
[ 6070.030303] Backtrace:
[ 6070.032806] [<bf1c2880>] (l2cap_add_conf_opt+0x0/0xf0 [l2cap]) from
[<bf1c6624>] (l2cap_recv_frame+0x1350/0x2e78 [l2cap])
[ 6070.043823]  r8:dc5d3100 r7:df2a91d6 r6:00000001 r5:df2a8000 r4:00000200
[ 6070.050659] [<bf1c52d4>] (l2cap_recv_frame+0x0/0x2e78 [l2cap]) from
[<bf1c8408>] (l2cap_recv_acldata+0x2bc/0x350 [l2cap])
[ 6070.061798] [<bf1c814c>] (l2cap_recv_acldata+0x0/0x350 [l2cap]) from
[<bf0037a4>] (hci_rx_task+0x244/0x478 [bluetooth])
[ 6070.072631]  r6:dc647700 r5:00000001 r4:df2ab740
[ 6070.077362] [<bf003560>] (hci_rx_task+0x0/0x478 [bluetooth]) from
[<c006b9fc>] (tasklet_action+0x78/0xd8)
[ 6070.087005] [<c006b984>] (tasklet_action+0x0/0xd8) from [<c006c160>]

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: Gustavo F. Padovan <gustavo@padovan.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
---
 net/bluetooth/l2cap.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 43e17f7..7794a2e 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -2832,6 +2832,11 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr
 			int len = cmd->len - sizeof(*rsp);
 			char req[64];
 
+			if (len > sizeof(req) - sizeof(struct l2cap_conf_req)) {
+				l2cap_send_disconn_req(conn, sk);
+				goto done;
+			}
+
 			/* throw out any old stored conf requests */
 			result = L2CAP_CONF_SUCCESS;
 			len = l2cap_parse_conf_rsp(sk, rsp->data,
-- 
1.6.6.1

Re: Pull request: bluetooth-2.6 2010-03-21

[David Miller]

From: Marcel Holtmann <marcel@holtmann.org>
Date: Sun, 21 Mar 2010 06:41:34 +0100

> these patches fix a potential remote denial of service in the L2CAP
> layer and a potential bad memory access with some sysfs files.

I've pulled this in thanks Marcel.