diff options
| author | Gary Lockyer <gary@catalyst.net.nz> | 2020-04-08 10:46:44 +1200 |
|---|---|---|
| committer | Karolin Seeger <kseeger@samba.org> | 2020-04-21 13:20:31 +0200 |
| commit | 40a58a973c0cfb7b259198c8f5df15ada39240ab (patch) | |
| tree | 18a373107f0a1629679e1902b0e68dc663fb4094 | |
| parent | 458b014a4d10e89f99cc0b54a815b50d6c817dce (diff) | |
| download | samba-40a58a973c0cfb7b259198c8f5df15ada39240ab.tar.gz | |
CVE-2020-10704 libcli ldap: Check search request lengths.
Check the search request lengths against the limits passed to
ldap_decode.
Credit to OSS-Fuzz
REF: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=20454
BUG: https://bugzilla.samba.org/show_bug.cgi?id=14334
Signed-off-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
| -rw-r--r-- | lib/util/asn1.c | 7 | ||||
| -rw-r--r-- | lib/util/asn1.h | 1 | ||||
| -rw-r--r-- | libcli/ldap/ldap_message.c | 4 |
3 files changed, 12 insertions, 0 deletions
diff --git a/lib/util/asn1.c b/lib/util/asn1.c index ee3cff9cb65..32d7981d28f 100644 --- a/lib/util/asn1.c +++ b/lib/util/asn1.c @@ -1159,3 +1159,10 @@ int asn1_peek_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size) *packet_size = size; return 0; } + +/* + * Get the length of the ASN.1 data + */ +size_t asn1_get_length(const struct asn1_data *asn1) { + return asn1->length; +} diff --git a/lib/util/asn1.h b/lib/util/asn1.h index fc365724e93..de92a767f14 100644 --- a/lib/util/asn1.h +++ b/lib/util/asn1.h @@ -106,5 +106,6 @@ bool asn1_extract_blob(struct asn1_data *asn1, TALLOC_CTX *mem_ctx, DATA_BLOB *pblob); void asn1_load_nocopy(struct asn1_data *data, uint8_t *buf, size_t len); int asn1_peek_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size); +size_t asn1_get_length(const struct asn1_data *asn1); #endif /* _ASN_1_H */ diff --git a/libcli/ldap/ldap_message.c b/libcli/ldap/ldap_message.c index d38fa0b3b61..69a48279532 100644 --- a/libcli/ldap/ldap_message.c +++ b/libcli/ldap/ldap_message.c @@ -1259,7 +1259,11 @@ _PUBLIC_ NTSTATUS ldap_decode(struct asn1_data *data, struct ldap_SearchRequest *r = &msg->r.SearchRequest; int sizelimit, timelimit; const char **attrs = NULL; + size_t request_size = asn1_get_length(data); msg->type = LDAP_TAG_SearchRequest; + if (request_size > limits->max_search_size) { + goto prot_err; + } if (!asn1_start_tag(data, tag)) goto prot_err; if (!asn1_read_OctetString_talloc(msg, data, &r->basedn)) goto prot_err; if (!asn1_read_enumerated(data, (int *)(void *)&(r->scope))) goto prot_err; |