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, 74 insertions, 0 deletions

diff --git a/fs/smb/server/Kconfig b/fs/smb/server/Kconfig
new file mode 100644
index 000000000..08d8b7a96
--- /dev/null
+++ b/fs/smb/server/Kconfig
@@ -0,0 +1,74 @@
+config SMB_SERVER
+	tristate "SMB3 server support"
+	depends on INET
+	depends on MULTIUSER
+	depends on FILE_LOCKING
+	select NLS
+	select NLS_UTF8
+	select NLS_UCS2_UTILS
+	select CRYPTO
+	select CRYPTO_LIB_AES_CBC_MACS
+	select CRYPTO_LIB_ARC4
+	select CRYPTO_LIB_DES
+	select CRYPTO_LIB_MD5
+	select CRYPTO_LIB_SHA256
+	select CRYPTO_LIB_SHA512
+	select CRYPTO_LIB_UTILS
+	select CRYPTO_AEAD2
+	select CRYPTO_CCM
+	select CRYPTO_GCM
+	select ASN1
+	select OID_REGISTRY
+	select CRC32
+	default n
+	help
+	  Choose Y here if you want to allow SMB3 compliant clients
+	  to access files residing on this system using SMB3 protocol.
+	  To compile the SMB3 server support as a module,
+	  choose M here: the module will be called ksmbd.
+
+	  You may choose to use a samba server instead, in which
+	  case you can choose N here.
+
+	  You also need to install user space programs which can be found
+	  in ksmbd-tools, available from
+	  https://github.com/cifsd-team/ksmbd-tools.
+	  More detail about how to run the ksmbd kernel server is
+	  available via the README file
+	  (https://github.com/cifsd-team/ksmbd-tools/blob/master/README).
+
+	  ksmbd kernel server includes support for auto-negotiation,
+	  Secure negotiate, Pre-authentication integrity, oplock/lease,
+	  compound requests, multi-credit, packet signing, RDMA(smbdirect),
+	  smb3 encryption, copy-offload, secure per-user session
+	  establishment via Kerberos or NTLMv2.
+
+if SMB_SERVER
+
+config SMB_SERVER_SMBDIRECT
+	bool "Support for SMB Direct protocol"
+	depends on SMB_SERVER && INFINIBAND && INFINIBAND_ADDR_TRANS
+	depends on SMB_SERVER=m || INFINIBAND=y
+	select SMBDIRECT
+	default n
+
+	help
+	  Enables SMB Direct support for SMB 3.0, 3.02 and 3.1.1.
+
+	  SMB Direct allows transferring SMB packets over RDMA. If unsure,
+	  say N.
+
+endif
+
+config SMB_SERVER_CHECK_CAP_NET_ADMIN
+	bool "Enable check network administration capability"
+	depends on SMB_SERVER
+	default y
+
+	help
+	  Prevent unprivileged processes to start the ksmbd kernel server.
+
+config SMB_SERVER_KERBEROS5
+	bool "Support for Kerberos 5"
+	depends on SMB_SERVER
+	default y