https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=f6be372ace889afa12163bd2c8a9cb717d7eff85
commit f6be372ace889afa12163bd2c8a9cb717d7eff85 Author: Takashi Yano <[email protected]> Date: Sun Mar 3 13:44:17 2024 +0900 Cygwin: pipe: Give up to use query_hdl for non-cygwin apps. Non-cygwin app may call ReadFile() for empty pipe, which makes NtQueryObject() for ObjectNameInformation block in fhandler_pipe:: get_query_hdl_per_process. Therefore, do not to try to get query_hdl for non-cygwin apps. Addresses: https://github.com/msys2/msys2-runtime/issues/202 Fixes: b531d6b06eeb ("Cygwin: pipe: Introduce temporary query_hdl.") Reported-by: Alisa Sireneva, Johannes Schindelin <[email protected]> Reviewed-by: Corinna Vinschen <[email protected]> Signed-off-by: Takashi Yano <[email protected]> Diff: --- winsup/cygwin/fhandler/pipe.cc | 57 ++++++++++-------------------------------- winsup/cygwin/release/3.5.2 | 4 +++ 2 files changed, 17 insertions(+), 44 deletions(-) diff --git a/winsup/cygwin/fhandler/pipe.cc b/winsup/cygwin/fhandler/pipe.cc index 1a97108b5..c877d89d7 100644 --- a/winsup/cygwin/fhandler/pipe.cc +++ b/winsup/cygwin/fhandler/pipe.cc @@ -1197,53 +1197,24 @@ HANDLE fhandler_pipe::get_query_hdl_per_process (WCHAR *name, OBJECT_NAME_INFORMATION *ntfn) { - NTSTATUS status; - ULONG len; - DWORD n_process = 256; - PSYSTEM_PROCESS_INFORMATION spi; - do - { /* Enumerate processes */ - DWORD nbytes = n_process * sizeof (SYSTEM_PROCESS_INFORMATION); - spi = (PSYSTEM_PROCESS_INFORMATION) HeapAlloc (GetProcessHeap (), - 0, nbytes); - if (!spi) - return NULL; - status = NtQuerySystemInformation (SystemProcessInformation, - spi, nbytes, &len); - if (NT_SUCCESS (status)) - break; - HeapFree (GetProcessHeap (), 0, spi); - n_process *= 2; - } - while (n_process < (1L<<20) && status == STATUS_INFO_LENGTH_MISMATCH); - if (!NT_SUCCESS (status)) - return NULL; + winpids pids ((DWORD) 0); - /* In most cases, it is faster to check the processes in reverse order. - To do this, store PIDs into an array. */ - DWORD *proc_pids = (DWORD *) HeapAlloc (GetProcessHeap (), 0, - n_process * sizeof (DWORD)); - if (!proc_pids) + /* In most cases, it is faster to check the processes in reverse order. */ + for (LONG i = (LONG) pids.npids - 1; i >= 0; i--) { - HeapFree (GetProcessHeap (), 0, spi); - return NULL; - } - PSYSTEM_PROCESS_INFORMATION p = spi; - n_process = 0; - while (true) - { - proc_pids[n_process++] = (DWORD)(intptr_t) p->UniqueProcessId; - if (!p->NextEntryOffset) - break; - p = (PSYSTEM_PROCESS_INFORMATION) ((char *) p + p->NextEntryOffset); - } - HeapFree (GetProcessHeap (), 0, spi); + NTSTATUS status; + ULONG len; + + /* Non-cygwin app may call ReadFile() for empty pipe, which makes + NtQueryObject() for ObjectNameInformation block. Therefore, do + not try to get query_hdl for non-cygwin apps. */ + _pinfo *p = pids[i]; + if (!p || ISSTATE (p, PID_NOTCYGWIN)) + continue; - for (LONG i = (LONG) n_process - 1; i >= 0; i--) - { HANDLE proc = OpenProcess (PROCESS_DUP_HANDLE | PROCESS_QUERY_INFORMATION, - 0, proc_pids[i]); + 0, p->dwProcessId); if (!proc) continue; @@ -1307,7 +1278,6 @@ fhandler_pipe::get_query_hdl_per_process (WCHAR *name, query_hdl_proc = proc; query_hdl_value = (HANDLE)(intptr_t) phi->Handles[j].HandleValue; HeapFree (GetProcessHeap (), 0, phi); - HeapFree (GetProcessHeap (), 0, proc_pids); return h; } close_handle: @@ -1317,6 +1287,5 @@ close_handle: close_proc: CloseHandle (proc); } - HeapFree (GetProcessHeap (), 0, proc_pids); return NULL; } diff --git a/winsup/cygwin/release/3.5.2 b/winsup/cygwin/release/3.5.2 index fd3c768de..e6782c1c0 100644 --- a/winsup/cygwin/release/3.5.2 +++ b/winsup/cygwin/release/3.5.2 @@ -9,3 +9,7 @@ Fixes: - Fix a race issue between console open() and close() which is caused by state mismatch between con.owner and console attaching state. Addresses: https://cygwin.com/pipermail/cygwin/2024-March/255575.html + +- Fix a problem that select() call for write-side of a pipe possibly + hangs with non-cygwin reader. + Addresses: https://github.com/msys2/msys2-runtime/issues/202
