diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-03 15:48:01 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-03 15:48:01 -0800 |
| commit | b65a0e0c84cf489bfa00d6aa6c48abc5a237100f (patch) | |
| tree | 3ed9d7b094e003a7b0d98234cb5b490d671bf3a9 /net | |
| parent | 4438a02fc4956f5f61918095708f183f5c63a9d3 (diff) | |
| parent | 1362fa078dae16776cd439791c6605b224ea6171 (diff) | |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
DNS: Fix a NULL pointer deref when trying to read an error key [CVE-2011-1076]
Diffstat (limited to 'net')
| -rw-r--r-- | net/dns_resolver/dns_key.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c index 739435a6af3..cfa7a5e1c5c 100644 --- a/net/dns_resolver/dns_key.c +++ b/net/dns_resolver/dns_key.c @@ -67,8 +67,9 @@ dns_resolver_instantiate(struct key *key, const void *_data, size_t datalen) size_t result_len = 0; const char *data = _data, *end, *opt; - kenter("%%%d,%s,'%s',%zu", - key->serial, key->description, data, datalen); + kenter("%%%d,%s,'%*.*s',%zu", + key->serial, key->description, + (int)datalen, (int)datalen, data, datalen); if (datalen <= 1 || !data || data[datalen - 1] != '\0') return -EINVAL; @@ -217,6 +218,19 @@ static void dns_resolver_describe(const struct key *key, struct seq_file *m) seq_printf(m, ": %u", key->datalen); } +/* + * read the DNS data + * - the key's semaphore is read-locked + */ +static long dns_resolver_read(const struct key *key, + char __user *buffer, size_t buflen) +{ + if (key->type_data.x[0]) + return key->type_data.x[0]; + + return user_read(key, buffer, buflen); +} + struct key_type key_type_dns_resolver = { .name = "dns_resolver", .instantiate = dns_resolver_instantiate, @@ -224,7 +238,7 @@ struct key_type key_type_dns_resolver = { .revoke = user_revoke, .destroy = user_destroy, .describe = dns_resolver_describe, - .read = user_read, + .read = dns_resolver_read, }; static int __init init_dns_resolver(void) |