File 0009-Fix-three-memory-leaks.patch of Package krb5

Overview Repositories Revisions Requests Users Attributes Meta

File 0009-Fix-three-memory-leaks.patch of Package krb5 (Revision 56ec846140e6ff939fc9f7c7193bc484)

Currently displaying revision 56ec846140e6ff939fc9f7c7193bc484 , Show latest

From 2aaffa96269b56fe09abf81851c40c9c4a3587f0 Mon Sep 17 00:00:00 2001
From: Greg Hudson <ghudson@mit.edu>
Date: Tue, 5 Mar 2024 17:38:49 -0500
Subject: [PATCH 1/2] Fix leak in KDC NDR encoding

If the KDC tries to encode a principal containing encode invalid UTF-8
sequences for inclusion in a PAC delegation info buffer, it will leak
a small amount of memory in enc_wchar_pointer() before failing.  Fix
the leak.

ticket: 9115 (new)
tags: pullup
target_version: 1.21-next

(cherry picked from commit 7d0d85bf99caf60c0afd4dcf91b0c4c683b983fe)
---
 src/kdc/ndr.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/kdc/ndr.c b/src/kdc/ndr.c
index 48395abe52..d438408ee2 100644
--- a/src/kdc/ndr.c
+++ b/src/kdc/ndr.c
@@ -96,14 +96,13 @@ enc_wchar_pointer(const char *utf8, struct encoded_wchars *encoded_out)
     size_t utf16len, num_wchars;
     uint8_t *utf16;
 
-    k5_buf_init_dynamic(&b);
-
     ret = k5_utf8_to_utf16le(utf8, &utf16, &utf16len);
     if (ret)
         return ret;
 
     num_wchars = utf16len / 2;
 
+    k5_buf_init_dynamic(&b);
     k5_buf_add_uint32_le(&b, num_wchars + 1);
     k5_buf_add_uint32_le(&b, 0);
     k5_buf_add_uint32_le(&b, num_wchars);
-- 
2.44.0

From 489deee29f427f22e2a26de729319bdb70819c37 Mon Sep 17 00:00:00 2001
From: Greg Hudson <ghudson@mit.edu>
Date: Tue, 5 Mar 2024 19:53:07 -0500
Subject: [PATCH 2/2] Fix two unlikely memory leaks

In gss_krb5int_make_seal_token_v3(), one of the bounds checks (which
could probably never be triggered) leaks plain.data.  Fix this leak
and use current practices for cleanup throughout the function.

In xmt_rmtcallres() (unused within the tree and likely elsewhere),
store port_ptr into crp->port_ptr as soon as it is allocated;
otherwise it could leak if the subsequent xdr_u_int32() operation
fails.

(cherry picked from commit c5f9c816107f70139de11b38aa02db2f1774ee0d)
---
 src/lib/gssapi/krb5/k5sealv3.c | 56 +++++++++++++++-------------------
 src/lib/rpc/pmap_rmt.c         |  9 +++---
 2 files changed, 29 insertions(+), 36 deletions(-)

diff --git a/src/lib/gssapi/krb5/k5sealv3.c b/src/lib/gssapi/krb5/k5sealv3.c
index 3b4f8cb837..e881eee835 100644
--- a/src/lib/gssapi/krb5/k5sealv3.c
+++ b/src/lib/gssapi/krb5/k5sealv3.c
@@ -65,7 +65,7 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
                                 int conf_req_flag, int toktype)
 {
     size_t bufsize = 16;
-    unsigned char *outbuf = 0;
+    unsigned char *outbuf = NULL;
     krb5_error_code err;
     int key_usage;
     unsigned char acceptor_flag;
@@ -75,9 +75,13 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
 #endif
     size_t ec;
     unsigned short tok_id;
-    krb5_checksum sum;
+    krb5_checksum sum = { 0 };
     krb5_key key;
     krb5_cksumtype cksumtype;
+    krb5_data plain = empty_data();
+
+    token->value = NULL;
+    token->length = 0;
 
     acceptor_flag = ctx->initiate ? 0 : FLAG_SENDER_IS_ACCEPTOR;
     key_usage = (toktype == KG_TOK_WRAP_MSG
@@ -107,14 +111,15 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
 #endif
 
     if (toktype == KG_TOK_WRAP_MSG && conf_req_flag) {
-        krb5_data plain;
         krb5_enc_data cipher;
         size_t ec_max;
         size_t encrypt_size;
 
         /* 300: Adds some slop.  */
-        if (SIZE_MAX - 300 < message->length)
-            return ENOMEM;
+        if (SIZE_MAX - 300 < message->length) {
+            err = ENOMEM;
+            goto cleanup;
+        }
         ec_max = SIZE_MAX - message->length - 300;
         if (ec_max > 0xffff)
             ec_max = 0xffff;
@@ -126,20 +131,20 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
 #endif
         err = alloc_data(&plain, message->length + 16 + ec);
         if (err)
-            return err;
+            goto cleanup;
 
         /* Get size of ciphertext.  */
         encrypt_size = krb5_encrypt_size(plain.length, key->keyblock.enctype);
         if (encrypt_size > SIZE_MAX / 2) {
             err = ENOMEM;
-            goto error;
+            goto cleanup;
         }
         bufsize = 16 + encrypt_size;
         /* Allocate space for header plus encrypted data.  */
         outbuf = gssalloc_malloc(bufsize);
         if (outbuf == NULL) {
-            free(plain.data);
-            return ENOMEM;
+            err = ENOMEM;
+            goto cleanup;
         }
 
         /* TOK_ID */
@@ -164,11 +169,8 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
         cipher.ciphertext.length = bufsize - 16;
         cipher.enctype = key->keyblock.enctype;
         err = krb5_k_encrypt(context, key, key_usage, 0, &plain, &cipher);
-        zap(plain.data, plain.length);
-        free(plain.data);
-        plain.data = 0;
         if (err)
-            goto error;
+            goto cleanup;
 
         /* Now that we know we're returning a valid token....  */
         ctx->seq_send++;
@@ -181,7 +183,6 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
         /* If the rotate fails, don't worry about it.  */
 #endif
     } else if (toktype == KG_TOK_WRAP_MSG && !conf_req_flag) {
-        krb5_data plain;
         size_t cksumsize;
 
         /* Here, message is the application-supplied data; message2 is
@@ -193,21 +194,19 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
     wrap_with_checksum:
         err = alloc_data(&plain, message->length + 16);
         if (err)
-            return err;
+            goto cleanup;
 
         err = krb5_c_checksum_length(context, cksumtype, &cksumsize);
         if (err)
-            goto error;
+            goto cleanup;
 
         assert(cksumsize <= 0xffff);
 
         bufsize = 16 + message2->length + cksumsize;
         outbuf = gssalloc_malloc(bufsize);
         if (outbuf == NULL) {
-            free(plain.data);
-            plain.data = 0;
             err = ENOMEM;
-            goto error;
+            goto cleanup;
         }
 
         /* TOK_ID */
@@ -239,23 +238,15 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
         if (message2->length)
             memcpy(outbuf + 16, message2->value, message2->length);
 
-        sum.contents = outbuf + 16 + message2->length;
-        sum.length = cksumsize;
-
         err = krb5_k_make_checksum(context, cksumtype, key,
                                    key_usage, &plain, &sum);
-        zap(plain.data, plain.length);
-        free(plain.data);
-        plain.data = 0;
         if (err) {
             zap(outbuf,bufsize);
-            goto error;
+            goto cleanup;
         }
         if (sum.length != cksumsize)
             abort();
         memcpy(outbuf + 16 + message2->length, sum.contents, cksumsize);
-        krb5_free_checksum_contents(context, &sum);
-        sum.contents = 0;
         /* Now that we know we're actually generating the token...  */
         ctx->seq_send++;
 
@@ -285,12 +276,13 @@ gss_krb5int_make_seal_token_v3 (krb5_context context,
 
     token->value = outbuf;
     token->length = bufsize;
-    return 0;
+    outbuf = NULL;
+    err = 0;
 
-error:
+cleanup:
+    krb5_free_checksum_contents(context, &sum);
+    zapfree(plain.data, plain.length);
     gssalloc_free(outbuf);
-    token->value = NULL;
-    token->length = 0;
     return err;
 }
 
diff --git a/src/lib/rpc/pmap_rmt.c b/src/lib/rpc/pmap_rmt.c
index 8c7e30c21a..0748af34a7 100644
--- a/src/lib/rpc/pmap_rmt.c
+++ b/src/lib/rpc/pmap_rmt.c
@@ -160,11 +160,12 @@ xdr_rmtcallres(
 	caddr_t port_ptr;
 
 	port_ptr = (caddr_t)(void *)crp->port_ptr;
-	if (xdr_reference(xdrs, &port_ptr, sizeof (uint32_t),
-	    xdr_u_int32) && xdr_u_int32(xdrs, &crp->resultslen)) {
-		crp->port_ptr = (uint32_t *)(void *)port_ptr;
+	if (!xdr_reference(xdrs, &port_ptr, sizeof (uint32_t),
+			   (xdrproc_t)xdr_u_int32))
+		return (FALSE);
+	crp->port_ptr = (uint32_t *)(void *)port_ptr;
+	if (xdr_u_int32(xdrs, &crp->resultslen))
 		return ((*(crp->xdr_results))(xdrs, crp->results_ptr));
-	}
 	return (FALSE);
 }
 
-- 
2.44.0

Places

File 0009-Fix-three-memory-leaks.patch of Package krb5 (Revision 56ec846140e6ff939fc9f7c7193bc484)

Places