From b78049831ffed65f0b4e61f69df14f3ab17922cb Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Tue, 20 Sep 2011 11:23:49 -0400 Subject: [PATCH 1/4] lib: add error checking to hex2bin hex2bin converts a hexadecimal string to its binary representation. The original version of hex2bin did not do any error checking. This patch adds error checking and returns the result. Changelog v1: - removed unpack_hex_byte() - changed return code from boolean to int Changelog: - use the new unpack_hex_byte() - add __must_check compiler option (Andy Shevchenko's suggestion) - change function API to return error checking result (based on Tetsuo Handa's initial patch) Signed-off-by: Mimi Zohar Acked-by: Andy Shevchenko --- include/linux/kernel.h | 2 +- lib/hexdump.c | 15 +++++++++++---- 2 files changed, 12 insertions(+), 5 deletions(-) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 46ac9a50528d..8eefcf7e95eb 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -382,7 +382,7 @@ static inline char *pack_hex_byte(char *buf, u8 byte) } extern int hex_to_bin(char ch); -extern void hex2bin(u8 *dst, const char *src, size_t count); +extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); /* * General tracing related utility functions - trace_printk(), diff --git a/lib/hexdump.c b/lib/hexdump.c index f5fe6ba7a3ab..51d5ae210244 100644 --- a/lib/hexdump.c +++ b/lib/hexdump.c @@ -38,14 +38,21 @@ EXPORT_SYMBOL(hex_to_bin); * @dst: binary result * @src: ascii hexadecimal string * @count: result length + * + * Return 0 on success, -1 in case of bad input. */ -void hex2bin(u8 *dst, const char *src, size_t count) +int hex2bin(u8 *dst, const char *src, size_t count) { while (count--) { - *dst = hex_to_bin(*src++) << 4; - *dst += hex_to_bin(*src++); - dst++; + int hi = hex_to_bin(*src++); + int lo = hex_to_bin(*src++); + + if ((hi < 0) || (lo < 0)) + return -1; + + *dst++ = (hi << 4) | lo; } + return 0; } EXPORT_SYMBOL(hex2bin); From 2684bf7f29cfb13ef2c60f3b3a53ee47d0db7022 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Tue, 20 Sep 2011 11:23:52 -0400 Subject: [PATCH 2/4] trusted-keys: check hex2bin result For each hex2bin call in trusted keys, check that the ascii hex string is valid. On failure, return -EINVAL. Changelog v1: - hex2bin now returns an int Signed-off-by: Mimi Zohar Acked-by: Andy Shevchenko --- security/keys/trusted.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/security/keys/trusted.c b/security/keys/trusted.c index 0c33e2ea1f3c..0964fc236946 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -779,7 +779,10 @@ static int getoptions(char *c, struct trusted_key_payload *pay, opt->pcrinfo_len = strlen(args[0].from) / 2; if (opt->pcrinfo_len > MAX_PCRINFO_SIZE) return -EINVAL; - hex2bin(opt->pcrinfo, args[0].from, opt->pcrinfo_len); + res = hex2bin(opt->pcrinfo, args[0].from, + opt->pcrinfo_len); + if (res < 0) + return -EINVAL; break; case Opt_keyhandle: res = strict_strtoul(args[0].from, 16, &handle); @@ -791,12 +794,18 @@ static int getoptions(char *c, struct trusted_key_payload *pay, case Opt_keyauth: if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE) return -EINVAL; - hex2bin(opt->keyauth, args[0].from, SHA1_DIGEST_SIZE); + res = hex2bin(opt->keyauth, args[0].from, + SHA1_DIGEST_SIZE); + if (res < 0) + return -EINVAL; break; case Opt_blobauth: if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE) return -EINVAL; - hex2bin(opt->blobauth, args[0].from, SHA1_DIGEST_SIZE); + res = hex2bin(opt->blobauth, args[0].from, + SHA1_DIGEST_SIZE); + if (res < 0) + return -EINVAL; break; case Opt_migratable: if (*args[0].from == '0') @@ -860,7 +869,9 @@ static int datablob_parse(char *datablob, struct trusted_key_payload *p, p->blob_len = strlen(c) / 2; if (p->blob_len > MAX_BLOB_SIZE) return -EINVAL; - hex2bin(p->blob, c, p->blob_len); + ret = hex2bin(p->blob, c, p->blob_len); + if (ret < 0) + return -EINVAL; ret = getoptions(datablob, p, o); if (ret < 0) return ret; From 2b3ff6319e2312656fbefe0209bef02d58b6836a Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Tue, 20 Sep 2011 11:23:55 -0400 Subject: [PATCH 3/4] encrypted-keys: check hex2bin result For each hex2bin call in encrypted keys, check that the ascii hex string is valid. On failure, return -EINVAL. Changelog v1: - hex2bin now returns an int Signed-off-by: Mimi Zohar Acked-by: Andy Shevchenko --- security/keys/encrypted-keys/encrypted.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index 3f577954b85a..f33804c1b4c8 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -667,11 +667,19 @@ static int encrypted_key_decrypt(struct encrypted_key_payload *epayload, return -EINVAL; hex_encoded_data = hex_encoded_iv + (2 * ivsize) + 2; - hex2bin(epayload->iv, hex_encoded_iv, ivsize); - hex2bin(epayload->encrypted_data, hex_encoded_data, encrypted_datalen); + ret = hex2bin(epayload->iv, hex_encoded_iv, ivsize); + if (ret < 0) + return -EINVAL; + ret = hex2bin(epayload->encrypted_data, hex_encoded_data, + encrypted_datalen); + if (ret < 0) + return -EINVAL; hmac = epayload->format + epayload->datablob_len; - hex2bin(hmac, hex_encoded_data + (encrypted_datalen * 2), HASH_SIZE); + ret = hex2bin(hmac, hex_encoded_data + (encrypted_datalen * 2), + HASH_SIZE); + if (ret < 0) + return -EINVAL; mkey = request_master_key(epayload, &master_key, &master_keylen); if (IS_ERR(mkey)) From 8c35ad20270de91d0f3bfe521daa3b7983ee8db7 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Fri, 16 Sep 2011 08:50:30 -0400 Subject: [PATCH 4/4] target: check hex2bin result Now that hex2bin does error checking, on error add debugging error msg. Changelog v1 (update): - fixed definition of 'ret' - hex2bin now returns an int Signed-off-by: Mimi Zohar Acked-by: Andy Shevchenko --- drivers/target/target_core_fabric_lib.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/target/target_core_fabric_lib.c b/drivers/target/target_core_fabric_lib.c index c4ea3a9a555b..39f021b855ef 100644 --- a/drivers/target/target_core_fabric_lib.c +++ b/drivers/target/target_core_fabric_lib.c @@ -63,6 +63,7 @@ u32 sas_get_pr_transport_id( unsigned char *buf) { unsigned char *ptr; + int ret; /* * Set PROTOCOL IDENTIFIER to 6h for SAS @@ -74,7 +75,9 @@ u32 sas_get_pr_transport_id( */ ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */ - hex2bin(&buf[4], ptr, 8); + ret = hex2bin(&buf[4], ptr, 8); + if (ret < 0) + pr_debug("sas transport_id: invalid hex string\n"); /* * The SAS Transport ID is a hardcoded 24-byte length @@ -156,8 +159,9 @@ u32 fc_get_pr_transport_id( unsigned char *buf) { unsigned char *ptr; - int i; + int i, ret; u32 off = 8; + /* * PROTOCOL IDENTIFIER is 0h for FCP-2 * @@ -174,7 +178,9 @@ u32 fc_get_pr_transport_id( i++; continue; } - hex2bin(&buf[off++], &ptr[i], 1); + ret = hex2bin(&buf[off++], &ptr[i], 1); + if (ret < 0) + pr_debug("fc transport_id: invalid hex string\n"); i += 2; } /*