Merge branch 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem fixes from James Morris:
- keys fixes via David Howells:
"A collection of fixes for Linux keyrings, mostly thanks to Eric
Biggers:
- Fix some PKCS#7 verification issues.
- Fix handling of unsupported crypto in X.509.
- Fix too-large allocation in big_key"
- Seccomp updates via Kees Cook:
"These are fixes for the get_metadata interface that landed during
-rc1. While the new selftest is strictly not a bug fix, I think
it's in the same spirit of avoiding bugs"
- an IMA build fix from Randy Dunlap
* 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
integrity/security: fix digsig.c build error with header file
KEYS: Use individual pages in big_key for crypto buffers
X.509: fix NULL dereference when restricting key with unsupported_sig
X.509: fix BUG_ON() when hash algorithm is unsupported
PKCS#7: fix direct verification of SignerInfo signature
PKCS#7: fix certificate blacklisting
PKCS#7: fix certificate chain verification
seccomp: add a selftest for get_metadata
ptrace, seccomp: tweak get_metadata behavior slightly
seccomp, ptrace: switch get_metadata types to arch independent
diff --git a/crypto/asymmetric_keys/pkcs7_trust.c b/crypto/asymmetric_keys/pkcs7_trust.c
index 1f4e25f..598906b 100644
--- a/crypto/asymmetric_keys/pkcs7_trust.c
+++ b/crypto/asymmetric_keys/pkcs7_trust.c
@@ -106,6 +106,7 @@
pr_devel("sinfo %u: Direct signer is key %x\n",
sinfo->index, key_serial(key));
x509 = NULL;
+ sig = sinfo->sig;
goto matched;
}
if (PTR_ERR(key) != -ENOKEY)
diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c
index 39e6de0..97c77f6 100644
--- a/crypto/asymmetric_keys/pkcs7_verify.c
+++ b/crypto/asymmetric_keys/pkcs7_verify.c
@@ -270,7 +270,7 @@
sinfo->index);
return 0;
}
- ret = public_key_verify_signature(p->pub, p->sig);
+ ret = public_key_verify_signature(p->pub, x509->sig);
if (ret < 0)
return ret;
x509->signer = p;
@@ -366,8 +366,7 @@
*
* (*) -EBADMSG if some part of the message was invalid, or:
*
- * (*) 0 if no signature chains were found to be blacklisted or to contain
- * unsupported crypto, or:
+ * (*) 0 if a signature chain passed verification, or:
*
* (*) -EKEYREJECTED if a blacklisted key was encountered, or:
*
@@ -423,8 +422,11 @@
for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) {
ret = pkcs7_verify_one(pkcs7, sinfo);
- if (sinfo->blacklisted && actual_ret == -ENOPKG)
- actual_ret = -EKEYREJECTED;
+ if (sinfo->blacklisted) {
+ if (actual_ret == -ENOPKG)
+ actual_ret = -EKEYREJECTED;
+ continue;
+ }
if (ret < 0) {
if (ret == -ENOPKG) {
sinfo->unsupported_crypto = true;
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index de99658..e929fe1 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -79,9 +79,11 @@
BUG_ON(!pkey);
BUG_ON(!sig);
- BUG_ON(!sig->digest);
BUG_ON(!sig->s);
+ if (!sig->digest)
+ return -ENOPKG;
+
alg_name = sig->pkey_algo;
if (strcmp(sig->pkey_algo, "rsa") == 0) {
/* The data wangled by the RSA algorithm is typically padded
diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c
index 86fb685..7c93c77 100644
--- a/crypto/asymmetric_keys/restrict.c
+++ b/crypto/asymmetric_keys/restrict.c
@@ -67,8 +67,9 @@
*
* Returns 0 if the new certificate was accepted, -ENOKEY if we couldn't find a
* matching parent certificate in the trusted list, -EKEYREJECTED if the
- * signature check fails or the key is blacklisted and some other error if
- * there is a matching certificate but the signature check cannot be performed.
+ * signature check fails or the key is blacklisted, -ENOPKG if the signature
+ * uses unsupported crypto, or some other error if there is a matching
+ * certificate but the signature check cannot be performed.
*/
int restrict_link_by_signature(struct key *dest_keyring,
const struct key_type *type,
@@ -88,6 +89,8 @@
return -EOPNOTSUPP;
sig = payload->data[asym_auth];
+ if (!sig)
+ return -ENOPKG;
if (!sig->auth_ids[0] && !sig->auth_ids[1])
return -ENOKEY;
@@ -139,6 +142,8 @@
return -EOPNOTSUPP;
sig = payload->data[asym_auth];
+ if (!sig)
+ return -ENOPKG;
if (!sig->auth_ids[0] && !sig->auth_ids[1])
return -ENOKEY;
@@ -222,9 +227,9 @@
*
* Returns 0 if the new certificate was accepted, -ENOKEY if we
* couldn't find a matching parent certificate in the trusted list,
- * -EKEYREJECTED if the signature check fails, and some other error if
- * there is a matching certificate but the signature check cannot be
- * performed.
+ * -EKEYREJECTED if the signature check fails, -ENOPKG if the signature uses
+ * unsupported crypto, or some other error if there is a matching certificate
+ * but the signature check cannot be performed.
*/
int restrict_link_by_key_or_keyring(struct key *dest_keyring,
const struct key_type *type,
@@ -249,9 +254,9 @@
*
* Returns 0 if the new certificate was accepted, -ENOKEY if we
* couldn't find a matching parent certificate in the trusted list,
- * -EKEYREJECTED if the signature check fails, and some other error if
- * there is a matching certificate but the signature check cannot be
- * performed.
+ * -EKEYREJECTED if the signature check fails, -ENOPKG if the signature uses
+ * unsupported crypto, or some other error if there is a matching certificate
+ * but the signature check cannot be performed.
*/
int restrict_link_by_key_or_keyring_chain(struct key *dest_keyring,
const struct key_type *type,
diff --git a/include/uapi/linux/ptrace.h b/include/uapi/linux/ptrace.h
index e46d82b..d5a1b8a 100644
--- a/include/uapi/linux/ptrace.h
+++ b/include/uapi/linux/ptrace.h
@@ -69,8 +69,8 @@
#define PTRACE_SECCOMP_GET_METADATA 0x420d
struct seccomp_metadata {
- unsigned long filter_off; /* Input: which filter */
- unsigned int flags; /* Output: filter's flags */
+ __u64 filter_off; /* Input: which filter */
+ __u64 flags; /* Output: filter's flags */
};
/* Read signals from a shared (process wide) queue */
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 940fa40..dc77548 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -1076,14 +1076,16 @@
size = min_t(unsigned long, size, sizeof(kmd));
- if (copy_from_user(&kmd, data, size))
+ if (size < sizeof(kmd.filter_off))
+ return -EINVAL;
+
+ if (copy_from_user(&kmd.filter_off, data, sizeof(kmd.filter_off)))
return -EFAULT;
filter = get_nth_filter(task, kmd.filter_off);
if (IS_ERR(filter))
return PTR_ERR(filter);
- memset(&kmd, 0, sizeof(kmd));
if (filter->log)
kmd.flags |= SECCOMP_FILTER_FLAG_LOG;
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index 6f9e4ce..9bb0a7f 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -18,6 +18,7 @@
#include <linux/cred.h>
#include <linux/key-type.h>
#include <linux/digsig.h>
+#include <linux/vmalloc.h>
#include <crypto/public_key.h>
#include <keys/system_keyring.h>
diff --git a/security/keys/big_key.c b/security/keys/big_key.c
index 929e149..fa728f6 100644
--- a/security/keys/big_key.c
+++ b/security/keys/big_key.c
@@ -22,6 +22,13 @@
#include <keys/big_key-type.h>
#include <crypto/aead.h>
+struct big_key_buf {
+ unsigned int nr_pages;
+ void *virt;
+ struct scatterlist *sg;
+ struct page *pages[];
+};
+
/*
* Layout of key payload words.
*/
@@ -91,10 +98,9 @@
/*
* Encrypt/decrypt big_key data
*/
-static int big_key_crypt(enum big_key_op op, u8 *data, size_t datalen, u8 *key)
+static int big_key_crypt(enum big_key_op op, struct big_key_buf *buf, size_t datalen, u8 *key)
{
int ret;
- struct scatterlist sgio;
struct aead_request *aead_req;
/* We always use a zero nonce. The reason we can get away with this is
* because we're using a different randomly generated key for every
@@ -109,8 +115,7 @@
return -ENOMEM;
memset(zero_nonce, 0, sizeof(zero_nonce));
- sg_init_one(&sgio, data, datalen + (op == BIG_KEY_ENC ? ENC_AUTHTAG_SIZE : 0));
- aead_request_set_crypt(aead_req, &sgio, &sgio, datalen, zero_nonce);
+ aead_request_set_crypt(aead_req, buf->sg, buf->sg, datalen, zero_nonce);
aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
aead_request_set_ad(aead_req, 0);
@@ -130,21 +135,81 @@
}
/*
+ * Free up the buffer.
+ */
+static void big_key_free_buffer(struct big_key_buf *buf)
+{
+ unsigned int i;
+
+ if (buf->virt) {
+ memset(buf->virt, 0, buf->nr_pages * PAGE_SIZE);
+ vunmap(buf->virt);
+ }
+
+ for (i = 0; i < buf->nr_pages; i++)
+ if (buf->pages[i])
+ __free_page(buf->pages[i]);
+
+ kfree(buf);
+}
+
+/*
+ * Allocate a buffer consisting of a set of pages with a virtual mapping
+ * applied over them.
+ */
+static void *big_key_alloc_buffer(size_t len)
+{
+ struct big_key_buf *buf;
+ unsigned int npg = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ unsigned int i, l;
+
+ buf = kzalloc(sizeof(struct big_key_buf) +
+ sizeof(struct page) * npg +
+ sizeof(struct scatterlist) * npg,
+ GFP_KERNEL);
+ if (!buf)
+ return NULL;
+
+ buf->nr_pages = npg;
+ buf->sg = (void *)(buf->pages + npg);
+ sg_init_table(buf->sg, npg);
+
+ for (i = 0; i < buf->nr_pages; i++) {
+ buf->pages[i] = alloc_page(GFP_KERNEL);
+ if (!buf->pages[i])
+ goto nomem;
+
+ l = min_t(size_t, len, PAGE_SIZE);
+ sg_set_page(&buf->sg[i], buf->pages[i], l, 0);
+ len -= l;
+ }
+
+ buf->virt = vmap(buf->pages, buf->nr_pages, VM_MAP, PAGE_KERNEL);
+ if (!buf->virt)
+ goto nomem;
+
+ return buf;
+
+nomem:
+ big_key_free_buffer(buf);
+ return NULL;
+}
+
+/*
* Preparse a big key
*/
int big_key_preparse(struct key_preparsed_payload *prep)
{
+ struct big_key_buf *buf;
struct path *path = (struct path *)&prep->payload.data[big_key_path];
struct file *file;
u8 *enckey;
- u8 *data = NULL;
ssize_t written;
- size_t datalen = prep->datalen;
+ size_t datalen = prep->datalen, enclen = datalen + ENC_AUTHTAG_SIZE;
int ret;
- ret = -EINVAL;
if (datalen <= 0 || datalen > 1024 * 1024 || !prep->data)
- goto error;
+ return -EINVAL;
/* Set an arbitrary quota */
prep->quotalen = 16;
@@ -157,13 +222,12 @@
*
* File content is stored encrypted with randomly generated key.
*/
- size_t enclen = datalen + ENC_AUTHTAG_SIZE;
loff_t pos = 0;
- data = kmalloc(enclen, GFP_KERNEL);
- if (!data)
+ buf = big_key_alloc_buffer(enclen);
+ if (!buf)
return -ENOMEM;
- memcpy(data, prep->data, datalen);
+ memcpy(buf->virt, prep->data, datalen);
/* generate random key */
enckey = kmalloc(ENC_KEY_SIZE, GFP_KERNEL);
@@ -176,7 +240,7 @@
goto err_enckey;
/* encrypt aligned data */
- ret = big_key_crypt(BIG_KEY_ENC, data, datalen, enckey);
+ ret = big_key_crypt(BIG_KEY_ENC, buf, datalen, enckey);
if (ret)
goto err_enckey;
@@ -187,7 +251,7 @@
goto err_enckey;
}
- written = kernel_write(file, data, enclen, &pos);
+ written = kernel_write(file, buf->virt, enclen, &pos);
if (written != enclen) {
ret = written;
if (written >= 0)
@@ -202,7 +266,7 @@
*path = file->f_path;
path_get(path);
fput(file);
- kzfree(data);
+ big_key_free_buffer(buf);
} else {
/* Just store the data in a buffer */
void *data = kmalloc(datalen, GFP_KERNEL);
@@ -220,7 +284,7 @@
err_enckey:
kzfree(enckey);
error:
- kzfree(data);
+ big_key_free_buffer(buf);
return ret;
}
@@ -298,15 +362,15 @@
return datalen;
if (datalen > BIG_KEY_FILE_THRESHOLD) {
+ struct big_key_buf *buf;
struct path *path = (struct path *)&key->payload.data[big_key_path];
struct file *file;
- u8 *data;
u8 *enckey = (u8 *)key->payload.data[big_key_data];
size_t enclen = datalen + ENC_AUTHTAG_SIZE;
loff_t pos = 0;
- data = kmalloc(enclen, GFP_KERNEL);
- if (!data)
+ buf = big_key_alloc_buffer(enclen);
+ if (!buf)
return -ENOMEM;
file = dentry_open(path, O_RDONLY, current_cred());
@@ -316,26 +380,26 @@
}
/* read file to kernel and decrypt */
- ret = kernel_read(file, data, enclen, &pos);
+ ret = kernel_read(file, buf->virt, enclen, &pos);
if (ret >= 0 && ret != enclen) {
ret = -EIO;
goto err_fput;
}
- ret = big_key_crypt(BIG_KEY_DEC, data, enclen, enckey);
+ ret = big_key_crypt(BIG_KEY_DEC, buf, enclen, enckey);
if (ret)
goto err_fput;
ret = datalen;
/* copy decrypted data to user */
- if (copy_to_user(buffer, data, datalen) != 0)
+ if (copy_to_user(buffer, buf->virt, datalen) != 0)
ret = -EFAULT;
err_fput:
fput(file);
error:
- kzfree(data);
+ big_key_free_buffer(buf);
} else {
ret = datalen;
if (copy_to_user(buffer, key->payload.data[big_key_data],
diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 0b457e8..5df6099 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -141,6 +141,15 @@
#define SECCOMP_FILTER_FLAG_LOG 2
#endif
+#ifndef PTRACE_SECCOMP_GET_METADATA
+#define PTRACE_SECCOMP_GET_METADATA 0x420d
+
+struct seccomp_metadata {
+ __u64 filter_off; /* Input: which filter */
+ __u64 flags; /* Output: filter's flags */
+};
+#endif
+
#ifndef seccomp
int seccomp(unsigned int op, unsigned int flags, void *args)
{
@@ -2845,6 +2854,58 @@
EXPECT_EQ(errno, EOPNOTSUPP);
}
+TEST(get_metadata)
+{
+ pid_t pid;
+ int pipefd[2];
+ char buf;
+ struct seccomp_metadata md;
+
+ ASSERT_EQ(0, pipe(pipefd));
+
+ pid = fork();
+ ASSERT_GE(pid, 0);
+ if (pid == 0) {
+ struct sock_filter filter[] = {
+ BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
+ };
+ struct sock_fprog prog = {
+ .len = (unsigned short)ARRAY_SIZE(filter),
+ .filter = filter,
+ };
+
+ /* one with log, one without */
+ ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
+ SECCOMP_FILTER_FLAG_LOG, &prog));
+ ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));
+
+ ASSERT_EQ(0, close(pipefd[0]));
+ ASSERT_EQ(1, write(pipefd[1], "1", 1));
+ ASSERT_EQ(0, close(pipefd[1]));
+
+ while (1)
+ sleep(100);
+ }
+
+ ASSERT_EQ(0, close(pipefd[1]));
+ ASSERT_EQ(1, read(pipefd[0], &buf, 1));
+
+ ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
+ ASSERT_EQ(pid, waitpid(pid, NULL, 0));
+
+ md.filter_off = 0;
+ ASSERT_EQ(sizeof(md), ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md));
+ EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
+ EXPECT_EQ(md.filter_off, 0);
+
+ md.filter_off = 1;
+ ASSERT_EQ(sizeof(md), ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md));
+ EXPECT_EQ(md.flags, 0);
+ EXPECT_EQ(md.filter_off, 1);
+
+ ASSERT_EQ(0, kill(pid, SIGKILL));
+}
+
/*
* TODO:
* - add microbenchmarks
