openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted

sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user
pointers, v1 and v2, and swaps the words they point to in hand-written
assembly.

    l.lwz   r29,0(r4)
    l.lwz   r27,0(r5)
    l.sw    0(r4),r27
    l.sw    0(r5),r29

The pointers are not checked with access_ok(). The four memory
accesses also have no exception table entries.

A caller passes a kernel address as either pointer, and the syscall
reads from and writes to it directly.

This gives an unprivileged process a kernel read/write primitive. It
overwrites kernel data such as the sys_call_table, gaining code
execution in kernel context.

Check both pointers before entering the critical section. Add fixups
for the four memory accesses so faults on valid but unmapped user
addresses return -EFAULT.

[shorne@gmail.com: fix comment style]
Fixes: 9d02a4283e9c ("OpenRISC: Boot code")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>

1 files changed, 333 insertions, 0 deletions

diff --git a/fs/smb/server/smb2ops.c b/fs/smb/server/smb2ops.c
new file mode 100644
index 000000000..c9a32ee09
--- /dev/null
+++ b/fs/smb/server/smb2ops.c
@@ -0,0 +1,333 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
+ *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/slab.h>
+#include "glob.h"
+
+#include "auth.h"
+#include "connection.h"
+#include "smb_common.h"
+#include "server.h"
+#include "stats.h"
+
+static struct smb_version_values smb21_server_values = {
+	.version_string = SMB21_VERSION_STRING,
+	.protocol_id = SMB21_PROT_ID,
+	.req_capabilities = SMB2_GLOBAL_CAP_LARGE_MTU,
+	.max_read_size = SMB21_DEFAULT_IOSIZE,
+	.max_write_size = SMB21_DEFAULT_IOSIZE,
+	.max_trans_size = SMB21_DEFAULT_IOSIZE,
+	.max_credits = SMB2_MAX_CREDITS,
+	.large_lock_type = 0,
+	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
+	.shared_lock_type = SMB2_LOCKFLAG_SHARED,
+	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
+	.header_size = sizeof(struct smb2_hdr),
+	.max_header_size = MAX_SMB2_HDR_SIZE,
+	.read_rsp_size = sizeof(struct smb2_read_rsp),
+	.lock_cmd = SMB2_LOCK,
+	.cap_unix = 0,
+	.cap_nt_find = SMB2_NT_FIND,
+	.cap_large_files = SMB2_LARGE_FILES,
+	.create_lease_size = sizeof(struct create_lease),
+	.create_durable_size = sizeof(struct create_durable_rsp),
+	.create_mxac_size = sizeof(struct create_mxac_rsp),
+	.create_disk_id_size = sizeof(struct create_disk_id_rsp),
+	.create_posix_size = sizeof(struct create_posix_rsp),
+};
+
+static struct smb_version_values smb30_server_values = {
+	.version_string = SMB30_VERSION_STRING,
+	.protocol_id = SMB30_PROT_ID,
+	.req_capabilities = SMB2_GLOBAL_CAP_LARGE_MTU,
+	.max_read_size = SMB3_DEFAULT_IOSIZE,
+	.max_write_size = SMB3_DEFAULT_IOSIZE,
+	.max_trans_size = SMB3_DEFAULT_TRANS_SIZE,
+	.max_credits = SMB2_MAX_CREDITS,
+	.large_lock_type = 0,
+	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
+	.shared_lock_type = SMB2_LOCKFLAG_SHARED,
+	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
+	.header_size = sizeof(struct smb2_hdr),
+	.max_header_size = MAX_SMB2_HDR_SIZE,
+	.read_rsp_size = sizeof(struct smb2_read_rsp),
+	.lock_cmd = SMB2_LOCK,
+	.cap_unix = 0,
+	.cap_nt_find = SMB2_NT_FIND,
+	.cap_large_files = SMB2_LARGE_FILES,
+	.create_lease_size = sizeof(struct create_lease_v2),
+	.create_durable_size = sizeof(struct create_durable_rsp),
+	.create_durable_v2_size = sizeof(struct create_durable_rsp_v2),
+	.create_mxac_size = sizeof(struct create_mxac_rsp),
+	.create_disk_id_size = sizeof(struct create_disk_id_rsp),
+	.create_posix_size = sizeof(struct create_posix_rsp),
+};
+
+static struct smb_version_values smb302_server_values = {
+	.version_string = SMB302_VERSION_STRING,
+	.protocol_id = SMB302_PROT_ID,
+	.req_capabilities = SMB2_GLOBAL_CAP_LARGE_MTU,
+	.max_read_size = SMB3_DEFAULT_IOSIZE,
+	.max_write_size = SMB3_DEFAULT_IOSIZE,
+	.max_trans_size = SMB3_DEFAULT_TRANS_SIZE,
+	.max_credits = SMB2_MAX_CREDITS,
+	.large_lock_type = 0,
+	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
+	.shared_lock_type = SMB2_LOCKFLAG_SHARED,
+	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
+	.header_size = sizeof(struct smb2_hdr),
+	.max_header_size = MAX_SMB2_HDR_SIZE,
+	.read_rsp_size = sizeof(struct smb2_read_rsp),
+	.lock_cmd = SMB2_LOCK,
+	.cap_unix = 0,
+	.cap_nt_find = SMB2_NT_FIND,
+	.cap_large_files = SMB2_LARGE_FILES,
+	.create_lease_size = sizeof(struct create_lease_v2),
+	.create_durable_size = sizeof(struct create_durable_rsp),
+	.create_durable_v2_size = sizeof(struct create_durable_rsp_v2),
+	.create_mxac_size = sizeof(struct create_mxac_rsp),
+	.create_disk_id_size = sizeof(struct create_disk_id_rsp),
+	.create_posix_size = sizeof(struct create_posix_rsp),
+};
+
+static struct smb_version_values smb311_server_values = {
+	.version_string = SMB311_VERSION_STRING,
+	.protocol_id = SMB311_PROT_ID,
+	.req_capabilities = SMB2_GLOBAL_CAP_LARGE_MTU,
+	.max_read_size = SMB3_DEFAULT_IOSIZE,
+	.max_write_size = SMB3_DEFAULT_IOSIZE,
+	.max_trans_size = SMB3_DEFAULT_TRANS_SIZE,
+	.max_credits = SMB2_MAX_CREDITS,
+	.large_lock_type = 0,
+	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
+	.shared_lock_type = SMB2_LOCKFLAG_SHARED,
+	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
+	.header_size = sizeof(struct smb2_hdr),
+	.max_header_size = MAX_SMB2_HDR_SIZE,
+	.read_rsp_size = sizeof(struct smb2_read_rsp),
+	.lock_cmd = SMB2_LOCK,
+	.cap_unix = 0,
+	.cap_nt_find = SMB2_NT_FIND,
+	.cap_large_files = SMB2_LARGE_FILES,
+	.create_lease_size = sizeof(struct create_lease_v2),
+	.create_durable_size = sizeof(struct create_durable_rsp),
+	.create_durable_v2_size = sizeof(struct create_durable_rsp_v2),
+	.create_mxac_size = sizeof(struct create_mxac_rsp),
+	.create_disk_id_size = sizeof(struct create_disk_id_rsp),
+	.create_posix_size = sizeof(struct create_posix_rsp),
+};
+
+static struct smb_version_ops smb2_0_server_ops = {
+	.get_cmd_val		=	get_smb2_cmd_val,
+	.inc_reqs		=	ksmbd_counter_inc_reqs,
+	.init_rsp_hdr		=	init_smb2_rsp_hdr,
+	.set_rsp_status		=	set_smb2_rsp_status,
+	.allocate_rsp_buf       =       smb2_allocate_rsp_buf,
+	.set_rsp_credits	=	smb2_set_rsp_credits,
+	.check_user_session	=	smb2_check_user_session,
+	.get_ksmbd_tcon		=	smb2_get_ksmbd_tcon,
+	.is_sign_req		=	smb2_is_sign_req,
+	.check_sign_req		=	smb2_check_sign_req,
+	.set_sign_rsp		=	smb2_set_sign_rsp
+};
+
+static struct smb_version_ops smb3_0_server_ops = {
+	.get_cmd_val		=	get_smb2_cmd_val,
+	.inc_reqs		=	ksmbd_counter_inc_reqs,
+	.init_rsp_hdr		=	init_smb2_rsp_hdr,
+	.set_rsp_status		=	set_smb2_rsp_status,
+	.allocate_rsp_buf       =       smb2_allocate_rsp_buf,
+	.set_rsp_credits	=	smb2_set_rsp_credits,
+	.check_user_session	=	smb2_check_user_session,
+	.get_ksmbd_tcon		=	smb2_get_ksmbd_tcon,
+	.is_sign_req		=	smb2_is_sign_req,
+	.check_sign_req		=	smb3_check_sign_req,
+	.set_sign_rsp		=	smb3_set_sign_rsp,
+	.generate_signingkey	=	ksmbd_gen_smb30_signingkey,
+	.generate_encryptionkey	=	ksmbd_gen_smb30_encryptionkey,
+	.is_transform_hdr	=	smb3_is_transform_hdr,
+	.decrypt_req		=	smb3_decrypt_req,
+	.encrypt_resp		=	smb3_encrypt_resp
+};
+
+static struct smb_version_ops smb3_11_server_ops = {
+	.get_cmd_val		=	get_smb2_cmd_val,
+	.inc_reqs		=	ksmbd_counter_inc_reqs,
+	.init_rsp_hdr		=	init_smb2_rsp_hdr,
+	.set_rsp_status		=	set_smb2_rsp_status,
+	.allocate_rsp_buf       =       smb2_allocate_rsp_buf,
+	.set_rsp_credits	=	smb2_set_rsp_credits,
+	.check_user_session	=	smb2_check_user_session,
+	.get_ksmbd_tcon		=	smb2_get_ksmbd_tcon,
+	.is_sign_req		=	smb2_is_sign_req,
+	.check_sign_req		=	smb3_check_sign_req,
+	.set_sign_rsp		=	smb3_set_sign_rsp,
+	.generate_signingkey	=	ksmbd_gen_smb311_signingkey,
+	.generate_encryptionkey	=	ksmbd_gen_smb311_encryptionkey,
+	.is_transform_hdr	=	smb3_is_transform_hdr,
+	.decrypt_req		=	smb3_decrypt_req,
+	.encrypt_resp		=	smb3_encrypt_resp
+};
+
+static struct smb_version_cmds smb2_0_server_cmds[NUMBER_OF_SMB2_COMMANDS] = {
+	[SMB2_NEGOTIATE_HE]	=	{ .proc = smb2_negotiate_request, },
+	[SMB2_SESSION_SETUP_HE] =	{ .proc = smb2_sess_setup, },
+	[SMB2_TREE_CONNECT_HE]  =	{ .proc = smb2_tree_connect,},
+	[SMB2_TREE_DISCONNECT_HE]  =	{ .proc = smb2_tree_disconnect,},
+	[SMB2_LOGOFF_HE]	=	{ .proc = smb2_session_logoff,},
+	[SMB2_CREATE_HE]	=	{ .proc = smb2_open},
+	[SMB2_QUERY_INFO_HE]	=	{ .proc = smb2_query_info},
+	[SMB2_QUERY_DIRECTORY_HE] =	{ .proc = smb2_query_dir},
+	[SMB2_CLOSE_HE]		=	{ .proc = smb2_close},
+	[SMB2_ECHO_HE]		=	{ .proc = smb2_echo},
+	[SMB2_SET_INFO_HE]      =       { .proc = smb2_set_info},
+	[SMB2_READ_HE]		=	{ .proc = smb2_read},
+	[SMB2_WRITE_HE]		=	{ .proc = smb2_write},
+	[SMB2_FLUSH_HE]		=	{ .proc = smb2_flush},
+	[SMB2_CANCEL_HE]	=	{ .proc = smb2_cancel},
+	[SMB2_LOCK_HE]		=	{ .proc = smb2_lock},
+	[SMB2_IOCTL_HE]		=	{ .proc = smb2_ioctl},
+	[SMB2_OPLOCK_BREAK_HE]	=	{ .proc = smb2_oplock_break},
+	[SMB2_CHANGE_NOTIFY_HE]	=	{ .proc = smb2_notify},
+};
+
+/**
+ * init_smb2_1_server() - initialize a smb server connection with smb2.1
+ *			command dispatcher
+ * @conn:	connection instance
+ */
+void init_smb2_1_server(struct ksmbd_conn *conn)
+{
+	conn->vals = &smb21_server_values;
+	conn->ops = &smb2_0_server_ops;
+	conn->cmds = smb2_0_server_cmds;
+	conn->max_cmds = ARRAY_SIZE(smb2_0_server_cmds);
+	conn->signing_algorithm = SIGNING_ALG_HMAC_SHA256_LE;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_LEASING;
+}
+
+/**
+ * init_smb3_0_server() - initialize a smb server connection with smb3.0
+ *			command dispatcher
+ * @conn:	connection instance
+ */
+void init_smb3_0_server(struct ksmbd_conn *conn)
+{
+	conn->vals = &smb30_server_values;
+	conn->ops = &smb3_0_server_ops;
+	conn->cmds = smb2_0_server_cmds;
+	conn->max_cmds = ARRAY_SIZE(smb2_0_server_cmds);
+	conn->signing_algorithm = SIGNING_ALG_AES_CMAC_LE;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_LEASING |
+			SMB2_GLOBAL_CAP_DIRECTORY_LEASING;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION &&
+	    conn->cli_cap & SMB2_GLOBAL_CAP_ENCRYPTION)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_ENCRYPTION;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION ||
+	    (!(server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION_OFF) &&
+	     conn->cli_cap & SMB2_GLOBAL_CAP_ENCRYPTION))
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_ENCRYPTION;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;
+}
+
+/**
+ * init_smb3_02_server() - initialize a smb server connection with smb3.02
+ *			command dispatcher
+ * @conn:	connection instance
+ */
+void init_smb3_02_server(struct ksmbd_conn *conn)
+{
+	conn->vals = &smb302_server_values;
+	conn->ops = &smb3_0_server_ops;
+	conn->cmds = smb2_0_server_cmds;
+	conn->max_cmds = ARRAY_SIZE(smb2_0_server_cmds);
+	conn->signing_algorithm = SIGNING_ALG_AES_CMAC_LE;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_LEASING |
+			SMB2_GLOBAL_CAP_DIRECTORY_LEASING;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION ||
+	    (!(server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION_OFF) &&
+	     conn->cli_cap & SMB2_GLOBAL_CAP_ENCRYPTION))
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_ENCRYPTION;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_PERSISTENT_HANDLES;
+}
+
+/**
+ * init_smb3_11_server() - initialize a smb server connection with smb3.11
+ *			command dispatcher
+ * @conn:	connection instance
+ */
+int init_smb3_11_server(struct ksmbd_conn *conn)
+{
+	conn->vals = &smb311_server_values;
+	conn->ops = &smb3_11_server_ops;
+	conn->cmds = smb2_0_server_cmds;
+	conn->max_cmds = ARRAY_SIZE(smb2_0_server_cmds);
+	conn->signing_algorithm = SIGNING_ALG_AES_CMAC_LE;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_LEASING |
+			SMB2_GLOBAL_CAP_DIRECTORY_LEASING;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;
+
+	if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE)
+		conn->vals->req_capabilities |= SMB2_GLOBAL_CAP_PERSISTENT_HANDLES;
+
+	INIT_LIST_HEAD(&conn->preauth_sess_table);
+	return 0;
+}
+
+void init_smb2_max_read_size(unsigned int sz)
+{
+	sz = clamp_val(sz, SMB3_MIN_IOSIZE, SMB3_MAX_IOSIZE);
+	smb21_server_values.max_read_size = sz;
+	smb30_server_values.max_read_size = sz;
+	smb302_server_values.max_read_size = sz;
+	smb311_server_values.max_read_size = sz;
+}
+
+void init_smb2_max_write_size(unsigned int sz)
+{
+	sz = clamp_val(sz, SMB3_MIN_IOSIZE, SMB3_MAX_IOSIZE);
+	smb21_server_values.max_write_size = sz;
+	smb30_server_values.max_write_size = sz;
+	smb302_server_values.max_write_size = sz;
+	smb311_server_values.max_write_size = sz;
+}
+
+void init_smb2_max_trans_size(unsigned int sz)
+{
+	sz = clamp_val(sz, SMB3_MIN_IOSIZE, SMB3_MAX_IOSIZE);
+	smb21_server_values.max_trans_size = sz;
+	smb30_server_values.max_trans_size = sz;
+	smb302_server_values.max_trans_size = sz;
+	smb311_server_values.max_trans_size = sz;
+}
+
+void init_smb2_max_credits(unsigned int sz)
+{
+	smb21_server_values.max_credits = sz;
+	smb30_server_values.max_credits = sz;
+	smb302_server_values.max_credits = sz;
+	smb311_server_values.max_credits = sz;
+}