[PATCH 8/12] openssh-4.3p2 return code check bugs

[Kylene Jo Hall]

The get_handle function can return a negative value.  The variable that
value is assigned to is eventually passed to handle_close which uses the
value as an array index thus not being able to handle negative values.
This patch adds the return code check and provides an appropriate error
exit in the event of a negative return code.  This entire set of patches
passed the regression tests on my system. Bugs found by Coverity.

Signed-off-by: Kylene Hall <kjhall at us.ibm.com>
---
sftp-server.c |   27 +++++++++++++++++++++++++--
1 files changed, 25 insertions(+), 2 deletions(-) 
diff -uprN openssh-4.3p2/sftp-server.c openssh-4.3p2-kylie/sftp-server.c
--- openssh-4.3p2/sftp-server.c	2006-01-02 06:40:51.000000000 -0600
+++ openssh-4.3p2-kylie/sftp-server.c	2006-05-08 15:42:04.795120304 -0500
@@ -408,9 +408,12 @@ process_close(void)
 
 	id = get_int();
 	handle = get_handle();
+	if (handle < 0)
+		goto out;
 	TRACE("close id %u handle %d", id, handle);
 	ret = handle_close(handle);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
+out:
 	send_status(id, status);
 }
 
@@ -424,6 +427,8 @@ process_read(void)
 
 	id = get_int();
 	handle = get_handle();
+	if (handle < 0)
+		goto out;
 	off = get_int64();
 	len = get_int();
 
@@ -450,6 +455,7 @@ process_read(void)
 			}
 		}
 	}
+out:
 	if (status != SSH2_FX_OK)
 		send_status(id, status);
 }
@@ -461,10 +467,12 @@ process_write(void)
 	u_int64_t off;
 	u_int len;
 	int handle, fd, ret, status = SSH2_FX_FAILURE;
-	char *data;
+	char *data = NULL;
 
 	id = get_int();
 	handle = get_handle();
+	if (handle < 0) 
+		goto out;
 	off = get_int64();
 	data = get_string(&len);
 
@@ -488,8 +496,10 @@ process_write(void)
 			}
 		}
 	}
+out:
 	send_status(id, status);
-	xfree(data);
+	if (data)
+		xfree(data);
 }
 
 static void
@@ -539,6 +549,8 @@ process_fstat(void)
 
 	id = get_int();
 	handle = get_handle();
+	if (handle < 0)
+		goto out;
 	TRACE("fstat id %u handle %d", id, handle);
 	fd = handle_to_fd(handle);
 	if (fd  >= 0) {
@@ -551,6 +563,7 @@ process_fstat(void)
 			status = SSH2_FX_OK;
 		}
 	}
+out:
 	if (status != SSH2_FX_OK)
 		send_status(id, status);
 }
@@ -614,6 +627,10 @@ process_fsetstat(void)
 
 	id = get_int();
 	handle = get_handle();
+	if (handle < 0) {
+		status = SSH2_FX_FAILURE;
+		goto out;
+	}
 	a = get_attrib();
 	TRACE("fsetstat id %u handle %d", id, handle);
 	fd = handle_to_fd(handle);
@@ -654,6 +671,7 @@ process_fsetstat(void)
 				status = errno_to_portable(errno);
 		}
 	}
+out:
 	send_status(id, status);
 }
 
@@ -697,6 +715,11 @@ process_readdir(void)
 
 	id = get_int();
 	handle = get_handle();
+	if (handle < 0) {
+		send_status(id, SSH2_FX_FAILURE);
+		return;
+	}
+
 	TRACE("readdir id %u handle %d", id, handle);
 	dirp = handle_to_dir(handle);
 	path = handle_to_name(handle);