linux/crypto
Eric Biggers d2890c3778 crypto: rsa - fix buffer overread when stripping leading zeroes
In rsa_get_n(), if the buffer contained all 0's and "FIPS mode" is
enabled, we would read one byte past the end of the buffer while
scanning the leading zeroes.  Fix it by checking 'n_sz' before '!*ptr'.

This bug was reachable by adding a specially crafted key of type
"asymmetric" (requires CONFIG_RSA and CONFIG_X509_CERTIFICATE_PARSER).

KASAN report:

    BUG: KASAN: slab-out-of-bounds in rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33
    Read of size 1 at addr ffff88003501a708 by task keyctl/196

    CPU: 1 PID: 196 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
    Call Trace:
     rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33
     asn1_ber_decoder+0x82a/0x1fd0 lib/asn1_decoder.c:328
     rsa_set_pub_key+0xd3/0x320 crypto/rsa.c:278
     crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline]
     pkcs1pad_set_pub_key+0xae/0x200 crypto/rsa-pkcs1pad.c:117
     crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline]
     public_key_verify_signature+0x270/0x9d0 crypto/asymmetric_keys/public_key.c:106
     x509_check_for_self_signed+0x2ea/0x480 crypto/asymmetric_keys/x509_public_key.c:141
     x509_cert_parse+0x46a/0x620 crypto/asymmetric_keys/x509_cert_parser.c:129
     x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
     asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
     key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
     SYSC_add_key security/keys/keyctl.c:122 [inline]
     SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
     entry_SYSCALL_64_fastpath+0x1f/0x96

    Allocated by task 196:
     __do_kmalloc mm/slab.c:3711 [inline]
     __kmalloc_track_caller+0x118/0x2e0 mm/slab.c:3726
     kmemdup+0x17/0x40 mm/util.c:118
     kmemdup ./include/linux/string.h:414 [inline]
     x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106
     x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
     asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
     key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
     SYSC_add_key security/keys/keyctl.c:122 [inline]
     SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
     entry_SYSCALL_64_fastpath+0x1f/0x96

Fixes: 5a7de97309 ("crypto: rsa - return raw integers for the ASN.1 parser")
Cc: <stable@vger.kernel.org> # v4.8+
Cc: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-29 13:39:14 +11:00
..
asymmetric_keys pkcs7: Set the module licence to prevent tainting 2017-11-15 16:38:45 +00:00
async_tx License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
.gitignore crypto: rsa - add .gitignore for crypto/*.-asn1.[ch] files 2015-06-25 23:29:24 +08:00
842.c crypto: acomp - add support for 842 via scomp 2016-10-25 11:08:33 +08:00
ablk_helper.c crypto: ablk_helper - Fix cryptd reordering 2016-06-23 18:29:53 +08:00
ablkcipher.c crypto: Replaced gcc specific attributes with macros from compiler.h 2017-01-13 00:24:39 +08:00
acompress.c crypto: acomp - allow registration of multiple acomps 2017-04-21 20:30:50 +08:00
aead.c crypto: Replaced gcc specific attributes with macros from compiler.h 2017-01-13 00:24:39 +08:00
aes_generic.c crypto: aes-generic - drop alignment requirement 2017-02-11 17:50:43 +08:00
aes_ti.c crypto: aes_ti - fix comment for MixColumns step 2017-06-19 14:11:53 +08:00
af_alg.c crypto: algif - move to generic async completion 2017-11-03 22:11:18 +08:00
ahash.c crypto: remove redundant backlog checks on EBUSY 2017-11-03 22:11:17 +08:00
akcipher.c crypto: Replaced gcc specific attributes with macros from compiler.h 2017-01-13 00:24:39 +08:00
algapi.c crypto: change transient busy return code to -ENOSPC 2017-11-03 22:11:16 +08:00
algboss.c crypto: algboss - remove redundant setting of len to zero 2017-10-07 12:10:34 +08:00
algif_aead.c crypto: algif - move to generic async completion 2017-11-03 22:11:18 +08:00
algif_hash.c crypto: algif - move to generic async completion 2017-11-03 22:11:18 +08:00
algif_rng.c crypto: algif_rng - Remove obsolete const-removal cast 2015-04-22 09:30:21 +08:00
algif_skcipher.c crypto: algif - move to generic async completion 2017-11-03 22:11:18 +08:00
ansi_cprng.c crypto: ansi_cprng - Convert to new rng interface 2015-04-22 09:30:18 +08:00
anubis.c
api.c crypto: introduce crypto wait for async op 2017-11-03 22:11:18 +08:00
arc4.c
authenc.c crypto: skcipher - Get rid of crypto_spawn_skcipher2() 2016-11-01 08:37:17 +08:00
authencesn.c crypto: authencesn - Fix digest_null crash 2017-07-18 17:01:11 +08:00
blkcipher.c crypto: Replaced gcc specific attributes with macros from compiler.h 2017-01-13 00:24:39 +08:00
blowfish_common.c
blowfish_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
camellia_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
cast5_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
cast6_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
cast_common.c
cbc.c crypto: cbc - Propagate NEED_FALLBACK bit 2017-03-09 18:34:39 +08:00
ccm.c crypto: ccm - preserve the IV buffer 2017-11-03 21:35:35 +08:00
chacha20_generic.c crypto: chacha20 - fix handling of chunked input 2017-08-22 14:45:47 +08:00
chacha20poly1305.c crypto: skcipher - Get rid of crypto_spawn_skcipher2() 2016-11-01 08:37:17 +08:00
cipher.c crypto: api - Remove no-op exit_ops code 2016-10-21 11:03:42 +08:00
cmac.c crypto: algapi - make crypto_xor() and crypto_inc() alignment agnostic 2017-02-11 17:52:28 +08:00
compress.c crypto: api - Remove no-op exit_ops code 2016-10-21 11:03:42 +08:00
crc32_generic.c crypto: crc32 - Rename generic implementation 2016-01-30 22:11:22 +08:00
crc32c_generic.c crypto: crc32c - Fix crc32c soft dependency 2016-01-19 15:52:10 +08:00
crct10dif_common.c
crct10dif_generic.c crypto: squash lines for simple wrapper functions 2016-09-13 20:27:26 +08:00
cryptd.c crypto: change transient busy return code to -ENOSPC 2017-11-03 22:11:16 +08:00
crypto_engine.c crypto: engine - replace pr_xxx by dev_xxx 2017-06-19 14:19:54 +08:00
crypto_null.c crypto: null - Remove default null blkcipher 2016-07-18 17:35:44 +08:00
crypto_user.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-05-02 16:40:27 -07:00
crypto_wq.c
ctr.c crypto: algapi - make crypto_xor() take separate dst and src arguments 2017-08-04 09:27:15 +08:00
cts.c crypto: remove redundant backlog checks on EBUSY 2017-11-03 22:11:17 +08:00
deflate.c crypto: scomp - add support for deflate rfc1950 (zlib) 2017-04-24 18:11:08 +08:00
des_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
dh_helper.c crypto: dh - Don't permit 'key' or 'g' size longer than 'p' 2017-11-10 19:20:17 +08:00
dh.c crypto: dh - Remove pointless checks for NULL 'p' and 'g' 2017-11-10 19:20:22 +08:00
drbg.c crypto: drbg - move to generic async completion 2017-11-03 22:11:19 +08:00
ecb.c
ecc_curve_defs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ecc.c crypto: ecdh - add privkey generation support 2017-06-10 12:04:35 +08:00
ecc.h crypto: ecdh - add privkey generation support 2017-06-10 12:04:35 +08:00
ecdh_helper.c crypto: ecdh - return unsigned value for crypto_ecdh_key_len() 2017-10-12 22:55:00 +08:00
ecdh.c crypto: ecdh - remove empty exit() 2017-11-06 14:45:04 +08:00
echainiv.c crypto: echainiv - Replace chaining with multiplication 2016-09-13 18:44:57 +08:00
fcrypt.c
fips.c crypto: fips - Move fips_enabled sysctl into fips.c 2015-04-23 14:18:09 +08:00
gcm.c crypto: gcm - move to generic async completion 2017-11-03 22:11:19 +08:00
gf128mul.c crypto: gf128mul - The x8_ble multiplication functions 2017-11-03 21:50:43 +08:00
ghash-generic.c crypto: ghash-generic - move common definitions to a new header file 2016-10-02 22:26:40 +08:00
hash_info.c keys, trusted: select hash algorithm for TPM2 chips 2015-12-20 15:27:12 +02:00
hmac.c crypto: hmac - add hmac IPAD/OPAD constant 2017-05-23 12:52:05 +08:00
internal.h crypto: api - Remove no-op exit_ops code 2016-10-21 11:03:42 +08:00
jitterentropy-kcapi.c crypto: jitterentropy - drop duplicate header module.h 2016-11-17 23:34:52 +08:00
jitterentropy.c crypto: jitterentropy - Delete unnecessary checks before the function call "kzfree" 2015-06-25 23:18:33 +08:00
Kconfig Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-11-14 10:52:09 -08:00
keywrap.c crypto: keywrap - simplify code 2017-10-12 22:55:06 +08:00
khazad.c
kpp.c crypto: Replaced gcc specific attributes with macros from compiler.h 2017-01-13 00:24:39 +08:00
lrw.c crypto: remove redundant backlog checks on EBUSY 2017-11-03 22:11:17 +08:00
lz4.c crypto: lz4 - fixed decompress function to return error code 2017-04-10 19:17:27 +08:00
lz4hc.c crypto: lz4 - fixed decompress function to return error code 2017-04-10 19:17:27 +08:00
lzo.c treewide: use kv[mz]alloc* rather than opencoded variants 2017-05-08 17:15:13 -07:00
Makefile Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-11-14 10:52:09 -08:00
mcryptd.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/stat.h> 2017-03-02 08:42:34 +01:00
md4.c
md5.c md5: remove from lib and only live in crypto 2017-03-24 22:02:56 +08:00
memneq.c
michael_mic.c
pcbc.c crypto: algapi - make crypto_xor() take separate dst and src arguments 2017-08-04 09:27:15 +08:00
pcrypt.c crypto: aead - Remove CRYPTO_ALG_AEAD_NEW flag 2015-08-17 16:53:53 +08:00
poly1305_generic.c crypto: poly1305 - Use unaligned access where required 2016-11-13 17:45:03 +08:00
proc.c crypto: fips - Move fips_enabled sysctl into fips.c 2015-04-23 14:18:09 +08:00
ripemd.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rmd128.c crypto: drop unnecessary return statements 2017-09-22 17:43:28 +08:00
rmd160.c crypto: drop unnecessary return statements 2017-09-22 17:43:28 +08:00
rmd256.c crypto: drop unnecessary return statements 2017-09-22 17:43:28 +08:00
rmd320.c crypto: drop unnecessary return statements 2017-09-22 17:43:28 +08:00
rng.c crypto: rng - ensure that the RNG is ready before using 2017-07-28 17:56:00 +08:00
rsa_helper.c crypto: rsa - fix buffer overread when stripping leading zeroes 2017-11-29 13:39:14 +11:00
rsa-pkcs1pad.c crypto: remove redundant backlog checks on EBUSY 2017-11-03 22:11:17 +08:00
rsa.c crypto: rsa - comply with crypto_akcipher_maxsize() 2017-06-10 12:04:30 +08:00
rsaprivkey.asn1 crypto: rsa - Store rest of the private key components 2016-07-05 23:05:26 +08:00
rsapubkey.asn1 crypto: akcipher - Changes to asymmetric key API 2015-10-14 22:23:16 +08:00
salsa20_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
scatterwalk.c crypto: scatterwalk - Remove unnecessary aliasing check in map_and_copy 2016-11-22 15:02:25 +08:00
scompress.c crypto: scompress - defer allocation of scratch buffer to first use 2017-08-03 13:52:44 +08:00
seed.c
seqiv.c crypto: algapi - make crypto_xor() and crypto_inc() alignment agnostic 2017-02-11 17:52:28 +08:00
serpent_generic.c crypto: serpent - improve __serpent_setkey with UBSAN 2017-08-09 20:17:54 +08:00
sha1_generic.c crypto: hash - add zero length message hash for shax and md5 2015-12-22 20:43:35 +08:00
sha3_generic.c crypto: sha3 - Add missing ULL suffixes for 64-bit constants 2016-08-08 23:43:46 +08:00
sha256_generic.c crypto: hash - add zero length message hash for shax and md5 2015-12-22 20:43:35 +08:00
sha512_generic.c crypto: sha512-generic - move to generic glue implementation 2015-04-10 21:39:41 +08:00
shash.c crypto: shash - Fix zero-length shash ahash digest crash 2017-10-11 00:34:07 +08:00
simd.c crypto: simd - Add simd skcipher helper 2016-11-28 21:23:18 +08:00
skcipher.c crypto: skcipher - Fix crash on zero-length input 2017-10-07 12:04:32 +08:00
sm3_generic.c crypto: sm3 - add OSCCA SM3 secure hash 2017-09-22 17:43:07 +08:00
tcrypt.c crypto: tcrypt - move to generic async completion 2017-11-03 22:11:22 +08:00
tcrypt.h crypto: tcrypt - Add ChaCha20/Poly1305 speed tests 2015-07-17 21:20:20 +08:00
tea.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
testmgr.c crypto: testmgr - move to generic async completion 2017-11-03 22:11:19 +08:00
testmgr.h crypto: sm3 - add SM3 test vectors 2017-09-22 17:43:08 +08:00
tgr192.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
twofish_common.c
twofish_generic.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
vmac.c
wp512.c crypto: add missing crypto module aliases 2015-01-13 22:29:11 +11:00
xcbc.c
xor.c kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2017-11-15 18:21:04 -08:00
xts.c Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-11-14 10:52:09 -08:00