diff options
Diffstat (limited to 'security')
| -rw-r--r-- | security/Kconfig | 40 | ||||
| -rw-r--r-- | security/keys/encrypted-keys/encrypted.c | 11 |
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); |