PenTest/nmap
1
0
Fork 0
mirror of https://github.com/nmap/nmap.git synced 2026-01-03 13:19:04 +00:00
Code Issues Projects Releases Wiki Activity

Correctly handle all cases for canceling IO in iocp engine

Browse Source
This commit is contained in:
dmiller
2024-10-08 21:14:43 +00:00
parent f765af4070
commit 167fafe65c
1 changed files with 40 additions and 22 deletions
Download Patch File Download Diff File Expand all files Collapse all files

62
nsock/src/engine_iocp.c
View File

@@ -574,8 +574,6 @@ static void free_eov(struct npool *nsp, struct extended_overlapped *eov) {
eov->readbuf = NULL;
}
eov->nse = NULL;
eov->nse_id = 0;
if (nse)
@@ -801,28 +799,48 @@ static void initiate_overlapped_event(struct npool *nsp, struct nevent *nse) {
/* Terminate an overlapped I/O operation that expired */
static void terminate_overlapped_event(struct npool *nsp, struct nevent *nse) {
struct extended_overlapped *eov = nse->eov;
DWORD dwCancelError = 0;
if (nse->eov) {
assert(nse->eov->nse_id != NSEID_FREED);
if (nse->eov->nse_id != NSEID_CANCELED && !HasOverlappedIoCompleted((LPOVERLAPPED)nse->eov)) {
assert(nse->eov->forced_operation == IOCP_NOT_FORCED);
nse->eov->nse_id = NSEID_CANCELED;
nse->eov->nse = NULL;
CancelIoEx((HANDLE)nse->iod->sd, (LPOVERLAPPED)nse->eov);
}
else {
if (nse->eov->forced_operation == IOCP_FORCED_POSTED) {
// forced operation already posted again.
// Mark it to be freed in iterate_through_event_lists.
nse->eov->nse_id = NSEID_CANCELED;
nse->eov->nse = NULL;
}
else {
free_eov(nsp, nse->eov);
}
}
nse->eov = NULL;
// If there's no I/O or it's already been canceled, just return.
if (!eov || eov->nse_id == NSEID_CANCELED) {
return;
}
assert(eov->nse_id != NSEID_FREED);
// Mark this as canceled
eov->nse_id = NSEID_CANCELED;
eov->nse = NULL;
nse->eov = NULL;
// If this is a forced operation that's been posted to the queue, we can't
// delete it yet and there's nothing left to cancel. Let
// iterate_through_event_lists free it next time through the loop.
if (eov->forced_operation == IOCP_FORCED_POSTED) {
return;
}
// If there's a pending I/O, cancel it.
if (!HasOverlappedIoCompleted((LPOVERLAPPED)eov)) {
// forced operations are never pending
assert(eov->forced_operation == IOCP_NOT_FORCED);
// If CancelIoEx succeeds, there will be a completion packet
if (CancelIoEx((HANDLE)nse->iod->sd, (LPOVERLAPPED)eov) != 0) {
return;
}
// If it failed, it could be there wasn't anything to cancel.
dwCancelError = GetLastError();
if (dwCancelError != ERROR_NOT_FOUND) {
fatal("Unexpected error from CancelIoEx: %08x", dwCancelError);
}
}
else if (eov->forced_operation == IOCP_NOT_FORCED) {
// real (not forced) IO completed, so this eov is referenced in the queue.
return;
}
// Now there are no more references to this eov, so we can free it.
free_eov(nsp, eov);
}
/* Retrieve the amount of bytes transferred or set the appropriate error */