gistfile1.txt

From 0036429f2f7fd1dff7a9b80d52e58f2f791e6b2b Mon Sep 17 00:00:00 2001
From: Brendan Bates <-------------->
Date: Mon, 8 May 2017 15:19:30 -0400
Subject: [PATCH] DTECTIT-41 - Fix issue stemming from the improper cleanup of uncancelled file descriptors in Win32.

---
 libusb/io.c                   | 38 ++++++++++++++++++++++++++++++++++++--
 libusb/os/windows_nt_common.c | 10 +++++++---
 msvc/libusb_dll_2015.vcxproj  |  4 ++--
 3 files changed, 45 insertions(+), 7 deletions(-)

diff --git a/libusb/io.c b/libusb/io.c
index bf2b5fa..f01c8d5 100644
--- a/libusb/io.c
+++ b/libusb/io.c
@@ -1978,7 +1978,7 @@ int API_EXPORTED libusb_wait_for_event(libusb_context *ctx, struct timeval *tv)
 		return (r == ETIMEDOUT);
 }
 
-static void handle_timeout(struct usbi_transfer *itransfer)
+static int handle_timeout(struct usbi_transfer *itransfer)
 {
 	struct libusb_transfer *transfer =
 		USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
@@ -1991,6 +1991,8 @@ static void handle_timeout(struct usbi_transfer *itransfer)
 	else
 		usbi_warn(TRANSFER_CTX(transfer),
 			"async cancel failed %d errno=%d", r, errno);
+
+	return r;
 }
 
 static int handle_timeouts_locked(struct libusb_context *ctx)
@@ -2010,6 +2012,9 @@ static int handle_timeouts_locked(struct libusb_context *ctx)
 
 	TIMESPEC_TO_TIMEVAL(&systime, &systime_ts);
 
+	int remove_size = 0;
+	struct usbi_transfer **remove_list = 0;
+
 	/* iterate through flying transfers list, finding all transfers that
 	 * have expired timeouts */
 	list_for_each_entry(transfer, &ctx->flying_transfers, list, struct usbi_transfer) {
@@ -2030,8 +2035,37 @@ static int handle_timeouts_locked(struct libusb_context *ctx)
 			return 0;
 
 		/* otherwise, we've got an expired timeout to handle */
-		handle_timeout(transfer);
+		int result = handle_timeout(transfer);
+
+		// Edge Case
+		// 
+		// If the transfer returned "no device", add this transfer to list of transfers that
+		// are unable to be cancelled.
+		if (result == LIBUSB_ERROR_NO_DEVICE) {
+			// Increment size of the remove list.
+			remove_size++;
+				
+			// Reallocate memory.
+			if (!remove_list) {
+				remove_list = malloc(sizeof(struct usbi_transfer *));
+			} else {
+				remove_list = realloc(remove_list, sizeof(struct usbi_transfer *) * remove_size);
+			}
+
+			// Add to the list.
+			remove_list[remove_size - 1] = transfer;
+		}
 	}
+
+	// Iterate through transfers unable to be cancelled and complete them with an error.
+	if (remove_size) {
+		for (int i = 0; i < remove_size; ++i) {
+			usbi_handle_transfer_completion(remove_list[i], LIBUSB_TRANSFER_STALL);
+		}
+
+		free(remove_list);
+	}
+
 	return 0;
 }
 
diff --git a/libusb/os/windows_nt_common.c b/libusb/os/windows_nt_common.c
index 68eb4a7..da9a8e6 100644
--- a/libusb/os/windows_nt_common.c
+++ b/libusb/os/windows_nt_common.c
@@ -577,9 +577,13 @@ int windows_handle_events(struct libusb_context *ctx, struct pollfd *fds, POLL_N
 			// newly allocated wfd that took the place of the one from the transfer.
 			windows_handle_callback(transfer, io_result, io_size);
 		} else {
-			usbi_err(ctx, "could not find a matching transfer for fd %d", fds[i]);
-			r = LIBUSB_ERROR_NOT_FOUND;
-			break;
+			// Remove the offending FD.
+			usbi_remove_pollfd(ctx, fds[i].fd);
+
+			// Free the memory used by the FD.
+			struct winfd removing_fd;
+			removing_fd.fd = fds[i].fd;
+			usbi_free_fd(&removing_fd);
 		}
 	}
 	usbi_mutex_unlock(&ctx->open_devs_lock);
--
libgit2 0.26.0