Merge tag 'v4.8' into patchwork

Linux 4.8

* tag 'v4.8': (1761 commits)
  Linux 4.8
  ARM: 8618/1: decompressor: reset ttbcr fields to use TTBR0 on ARMv7
  MIPS: CM: Fix mips_cm_max_vp_width for non-MT kernels on MT systems
  include/linux/property.h: fix typo/compile error
  ocfs2: fix deadlock on mmapped page in ocfs2_write_begin_nolock()
  mm: workingset: fix crash in shadow node shrinker caused by replace_page_cache_page()
  MAINTAINERS: Switch to kernel.org email address for Javi Merino
  x86/entry/64: Fix context tracking state warning when load_gs_index fails
  x86/boot: Initialize FPU and X86_FEATURE_ALWAYS even if we don't have CPUID
  x86/vdso: Fix building on big endian host
  x86/boot: Fix another __read_cr4() case on 486
  sctp: fix the issue sctp_diag uses lock_sock in rcu_read_lock
  sctp: change to check peer prsctp_capable when using prsctp polices
  sctp: remove prsctp_param from sctp_chunk
  sctp: move sent_count to the memory hole in sctp_chunk
  tg3: Avoid NULL pointer dereference in tg3_io_error_detected()
  x86/init: Fix cr4_init_shadow() on CR4-less machines
  MIPS: Fix detection of unsupported highmem with cache aliases
  MIPS: Malta: Fix IOCU disable switch read for MIPS64
  MIPS: Fix BUILD_ROLLBACK_PROLOGUE for microMIPS
  ...

2 files changed, 47 insertions, 4 deletions

diff --git a/security/Kconfig b/security/Kconfig
index 176758cdfa57..118f4549404e 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -118,6 +118,46 @@ config LSM_MMAP_MIN_ADDR
 	  this low address space will need the permission specific to the
 	  systems running LSM.
 
+config HAVE_HARDENED_USERCOPY_ALLOCATOR
+	bool
+	help
+	  The heap allocator implements __check_heap_object() for
+	  validating memory ranges against heap object sizes in
+	  support of CONFIG_HARDENED_USERCOPY.
+
+config HAVE_ARCH_HARDENED_USERCOPY
+	bool
+	help
+	  The architecture supports CONFIG_HARDENED_USERCOPY by
+	  calling check_object_size() just before performing the
+	  userspace copies in the low level implementation of
+	  copy_to_user() and copy_from_user().
+
+config HARDENED_USERCOPY
+	bool "Harden memory copies between kernel and userspace"
+	depends on HAVE_ARCH_HARDENED_USERCOPY
+	depends on HAVE_HARDENED_USERCOPY_ALLOCATOR
+	select BUG
+	help
+	  This option checks for obviously wrong memory regions when
+	  copying memory to/from the kernel (via copy_to_user() and
+	  copy_from_user() functions) by rejecting memory ranges that
+	  are larger than the specified heap object, span multiple
+	  separately allocates pages, are not on the process stack,
+	  or are part of the kernel text. This kills entire classes
+	  of heap overflow exploits and similar kernel memory exposures.
+
+config HARDENED_USERCOPY_PAGESPAN
+	bool "Refuse to copy allocations that span multiple pages"
+	depends on HARDENED_USERCOPY
+	depends on EXPERT
+	help
+	  When a multi-page allocation is done without __GFP_COMP,
+	  hardened usercopy will reject attempts to copy it. There are,
+	  however, several cases of this in the kernel that have not all
+	  been removed. This config is intended to be used only while
+	  trying to find such users.
+
 source security/selinux/Kconfig
 source security/smack/Kconfig
 source security/tomoyo/Kconfig
diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index 5adbfc32242f..17a06105ccb6 100644
--- a/security/keys/encrypted-keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -29,6 +29,7 @@
 #include <linux/rcupdate.h>
 #include <linux/scatterlist.h>
 #include <linux/ctype.h>
+#include <crypto/aes.h>
 #include <crypto/hash.h>
 #include <crypto/sha.h>
 #include <crypto/skcipher.h>
@@ -478,6 +479,7 @@ static int derived_key_encrypt(struct encrypted_key_payload *epayload,
 	struct crypto_skcipher *tfm;
 	struct skcipher_request *req;
 	unsigned int encrypted_datalen;
+	u8 iv[AES_BLOCK_SIZE];
 	unsigned int padlen;
 	char pad[16];
 	int ret;
@@ -500,8 +502,8 @@ static int derived_key_encrypt(struct encrypted_key_payload *epayload,
 	sg_init_table(sg_out, 1);
 	sg_set_buf(sg_out, epayload->encrypted_data, encrypted_datalen);
 
-	skcipher_request_set_crypt(req, sg_in, sg_out, encrypted_datalen,
-				   epayload->iv);
+	memcpy(iv, epayload->iv, sizeof(iv));
+	skcipher_request_set_crypt(req, sg_in, sg_out, encrypted_datalen, iv);
 	ret = crypto_skcipher_encrypt(req);
 	tfm = crypto_skcipher_reqtfm(req);
 	skcipher_request_free(req);
@@ -581,6 +583,7 @@ static int derived_key_decrypt(struct encrypted_key_payload *epayload,
 	struct crypto_skcipher *tfm;
 	struct skcipher_request *req;
 	unsigned int encrypted_datalen;
+	u8 iv[AES_BLOCK_SIZE];
 	char pad[16];
 	int ret;
 
@@ -599,8 +602,8 @@ static int derived_key_decrypt(struct encrypted_key_payload *epayload,
 		   epayload->decrypted_datalen);
 	sg_set_buf(&sg_out[1], pad, sizeof pad);
 
-	skcipher_request_set_crypt(req, sg_in, sg_out, encrypted_datalen,
-				   epayload->iv);
+	memcpy(iv, epayload->iv, sizeof(iv));
+	skcipher_request_set_crypt(req, sg_in, sg_out, encrypted_datalen, iv);
 	ret = crypto_skcipher_decrypt(req);
 	tfm = crypto_skcipher_reqtfm(req);
 	skcipher_request_free(req);