Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull key subsystem fixes from James Morris:
 "Fixes for the keys subsystem, one of which addresses a use-after-free
  bug"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  PEFILE: Relax the check on the length of the PKCS#7 cert
  KEYS: Fix use-after-free in assoc_array_gc()
  KEYS: Fix public_key asymmetric key subtype name
  KEYS: Increase root_maxkeys and root_maxbytes sizes
This commit is contained in:
Linus Torvalds 2014-09-03 10:09:40 -07:00
commit 5a147c9f57
4 changed files with 37 additions and 19 deletions

View File

@ -121,6 +121,7 @@ static int public_key_verify_signature_2(const struct key *key,
struct asymmetric_key_subtype public_key_subtype = { struct asymmetric_key_subtype public_key_subtype = {
.owner = THIS_MODULE, .owner = THIS_MODULE,
.name = "public_key", .name = "public_key",
.name_len = sizeof("public_key") - 1,
.describe = public_key_describe, .describe = public_key_describe,
.destroy = public_key_destroy, .destroy = public_key_destroy,
.verify_signature = public_key_verify_signature_2, .verify_signature = public_key_verify_signature_2,

View File

@ -128,6 +128,7 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
{ {
struct win_certificate wrapper; struct win_certificate wrapper;
const u8 *pkcs7; const u8 *pkcs7;
unsigned len;
if (ctx->sig_len < sizeof(wrapper)) { if (ctx->sig_len < sizeof(wrapper)) {
pr_debug("Signature wrapper too short\n"); pr_debug("Signature wrapper too short\n");
@ -154,33 +155,49 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
return -ENOTSUPP; return -ENOTSUPP;
} }
/* Looks like actual pkcs signature length is in wrapper->length. /* It looks like the pkcs signature length in wrapper->length and the
* size obtained from data dir entries lists the total size of * size obtained from the data dir entries, which lists the total size
* certificate table which is also aligned to octawrod boundary. * of certificate table, are both aligned to an octaword boundary, so
* * we may have to deal with some padding.
* So set signature length field appropriately.
*/ */
ctx->sig_len = wrapper.length; ctx->sig_len = wrapper.length;
ctx->sig_offset += sizeof(wrapper); ctx->sig_offset += sizeof(wrapper);
ctx->sig_len -= sizeof(wrapper); ctx->sig_len -= sizeof(wrapper);
if (ctx->sig_len == 0) { if (ctx->sig_len < 4) {
pr_debug("Signature data missing\n"); pr_debug("Signature data missing\n");
return -EKEYREJECTED; return -EKEYREJECTED;
} }
/* What's left should a PKCS#7 cert */ /* What's left should be a PKCS#7 cert */
pkcs7 = pebuf + ctx->sig_offset; pkcs7 = pebuf + ctx->sig_offset;
if (pkcs7[0] == (ASN1_CONS_BIT | ASN1_SEQ)) { if (pkcs7[0] != (ASN1_CONS_BIT | ASN1_SEQ))
if (pkcs7[1] == 0x82 && goto not_pkcs7;
pkcs7[2] == (((ctx->sig_len - 4) >> 8) & 0xff) &&
pkcs7[3] == ((ctx->sig_len - 4) & 0xff)) switch (pkcs7[1]) {
return 0; case 0 ... 0x7f:
if (pkcs7[1] == 0x80) len = pkcs7[1] + 2;
return 0; goto check_len;
if (pkcs7[1] > 0x82) case ASN1_INDEFINITE_LENGTH:
return -EMSGSIZE; return 0;
case 0x81:
len = pkcs7[2] + 3;
goto check_len;
case 0x82:
len = ((pkcs7[2] << 8) | pkcs7[3]) + 4;
goto check_len;
case 0x83 ... 0xff:
return -EMSGSIZE;
default:
goto not_pkcs7;
} }
check_len:
if (len <= ctx->sig_len) {
/* There may be padding */
ctx->sig_len = len;
return 0;
}
not_pkcs7:
pr_debug("Signature data not PKCS#7\n"); pr_debug("Signature data not PKCS#7\n");
return -ELIBBAD; return -ELIBBAD;
} }

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@ -1735,7 +1735,7 @@ int assoc_array_gc(struct assoc_array *array,
gc_complete: gc_complete:
edit->set[0].to = new_root; edit->set[0].to = new_root;
assoc_array_apply_edit(edit); assoc_array_apply_edit(edit);
edit->array->nr_leaves_on_tree = nr_leaves_on_tree; array->nr_leaves_on_tree = nr_leaves_on_tree;
return 0; return 0;
enomem: enomem:

View File

@ -27,8 +27,8 @@ DEFINE_SPINLOCK(key_serial_lock);
struct rb_root key_user_tree; /* tree of quota records indexed by UID */ struct rb_root key_user_tree; /* tree of quota records indexed by UID */
DEFINE_SPINLOCK(key_user_lock); DEFINE_SPINLOCK(key_user_lock);
unsigned int key_quota_root_maxkeys = 200; /* root's key count quota */ unsigned int key_quota_root_maxkeys = 1000000; /* root's key count quota */
unsigned int key_quota_root_maxbytes = 20000; /* root's key space quota */ unsigned int key_quota_root_maxbytes = 25000000; /* root's key space quota */
unsigned int key_quota_maxkeys = 200; /* general key count quota */ unsigned int key_quota_maxkeys = 200; /* general key count quota */
unsigned int key_quota_maxbytes = 20000; /* general key space quota */ unsigned int key_quota_maxbytes = 20000; /* general key space quota */