diff options
author | Adam Vartanian <flooey@google.com> | 2017-04-10 15:51:16 +0100 |
---|---|---|
committer | JP Sugarbroad <jpsugar@google.com> | 2017-05-19 00:25:07 -0700 |
commit | 47a7077d951fbc7b2c77f1859c00beb6ab5e0a74 (patch) | |
tree | f7665dd7b34aa5368957a3874d165272f2075ff3 | |
parent | 900d60440b97cb9bcad231e0095b8518475c04be (diff) | |
download | boringssl-nougat-mr1.8-release.tar.gz |
CVE 2016-2109 fixandroid-7.1.1_r61android-7.1.1_r60android-7.1.1_r59nougat-mr1.8-releasenougat-mr1-security-release
Read ASN.1 data in chunks to prevent invalid inputs from allocating
excessive amounts of data.
Bug: 35443725
Test: run cts -m CtsLibcoreTestCases
Test: manually ran testcase from OpenSSL
Change-Id: Ia9d6aa40726c0cba26e2060108112f33e00e8270
Merged-In: Ie00536d7ad815464b2b031f7bcd1b683e12c1623
Merged-In: If087a69ee075b3c5323abb8d7d740e92bd703bb1
Merged-In: If77e23607fc77f724f50ad0e0b94eef4beae57ea
Merged-In: Ia8d0370ece1d5c1750a4331810c610ed5c813224
Merged-In: Ia945d5ce50335919b0783fe909892703213454ef
(cherry picked from commit ea156ae109eac7b7cf7d4f6a76f3c4590734789b)
-rw-r--r-- | src/crypto/asn1/a_d2i_fp.c | 46 |
1 files changed, 31 insertions, 15 deletions
diff --git a/src/crypto/asn1/a_d2i_fp.c b/src/crypto/asn1/a_d2i_fp.c index 97ec75b5..af03bc0c 100644 --- a/src/crypto/asn1/a_d2i_fp.c +++ b/src/crypto/asn1/a_d2i_fp.c @@ -140,6 +140,7 @@ void *ASN1_item_d2i_fp(const ASN1_ITEM *it, FILE *in, void *x) #endif #define HEADER_SIZE 8 +#define ASN1_CHUNK_INITIAL_SIZE (16 * 1024) static int asn1_d2i_read_bio(BIO *in, BUF_MEM **pb) { BUF_MEM *b; @@ -231,6 +232,7 @@ static int asn1_d2i_read_bio(BIO *in, BUF_MEM **pb) want=c.slen; if (want > (len-off)) { + size_t chunk_max = ASN1_CHUNK_INITIAL_SIZE; want-=(len-off); if (want > INT_MAX /* BIO_read takes an int length */ || len+want < len) @@ -238,23 +240,37 @@ static int asn1_d2i_read_bio(BIO *in, BUF_MEM **pb) OPENSSL_PUT_ERROR(ASN1, ASN1_R_TOO_LONG); goto err; } - if (!BUF_MEM_grow_clean(b,len+want)) - { - OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE); - goto err; - } while (want > 0) { - i=BIO_read(in,&(b->data[len]),want); - if (i <= 0) - { - OPENSSL_PUT_ERROR(ASN1, ASN1_R_NOT_ENOUGH_DATA); - goto err; - } - /* This can't overflow because - * |len+want| didn't overflow. */ - len+=i; - want-=i; + + /* + * Read content in chunks of increasing size + * so we can return an error for EOF without + * having to allocate the entire content length + * in one go. + */ + size_t chunk = want > chunk_max ? chunk_max : want; + + if (!BUF_MEM_grow_clean(b, len + chunk)) { + OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE); + goto err; + } + want -= chunk; + while (chunk > 0) { + i = BIO_read(in, &(b->data[len]), chunk); + if (i <= 0) { + OPENSSL_PUT_ERROR(ASN1, ASN1_R_NOT_ENOUGH_DATA); + goto err; + } + /* + * This can't overflow because |len+want| didn't + * overflow. + */ + len += i; + chunk -= i; + } + if (chunk_max < INT_MAX/2) + chunk_max *= 2; } } if (off + c.slen < off) |