From dac0b6826bef8c637866c60d15ffd8461b361f50 Mon Sep 17 00:00:00 2001 From: Michael Haubenwallner Date: Wed, 7 Dec 2016 11:58:26 +0100 Subject: [PATCH] dll_list: Track main executable and cygwin1.dll. Even for the main executable and cygwin1.dll store the file name as full NT path. Create the child process using the main executable's file name converted from the full NT path stored before. * dll_init.cc (dll_list::alloc): Search for DLL_SELF type entry with module name like for DLL_LINK, use full NT path to search for DLL_LOAD type only. For DLL_SELF type do not indicate having a destructor to be called. (dll_list::find): Ignore DLL_SELF type entries. (dll_list::init): Ditto. Call track_self method. (dll_list::track_self): New. (dll_list::load_after_fork): Call track_self method. * dll_init.h (enum dll_type): Add DLL_SELF, for the main executable and cygwin1.dll. (struct dll_list): Declare private method track_self. Declare member variable main_executable. * fork.cc (frok::parent): Use ntname from dlls.main_executable to create child process, converted to short path using dll_list::buffered_shortname. --- winsup/cygwin/dll_init.cc | 26 ++++++++++++++++++++------ winsup/cygwin/dll_init.h | 4 ++++ winsup/cygwin/fork.cc | 15 ++++++++++++--- 3 files changed, 36 insertions(+), 9 deletions(-) diff --git a/winsup/cygwin/dll_init.cc b/winsup/cygwin/dll_init.cc index f94c6698d..2204533c6 100644 --- a/winsup/cygwin/dll_init.cc +++ b/winsup/cygwin/dll_init.cc @@ -306,8 +306,9 @@ dll_list::alloc (HINSTANCE h, per_process *p, dll_type type) guard (true); /* Already loaded? For linked DLLs, only compare the basenames. Linked DLLs are loaded using just the basename and the default DLL search path. - The Windows loader picks up the first one it finds. */ - dll *d = (type == DLL_LINK) ? dlls.find_by_modname (modname) : dlls[ntname]; + The Windows loader picks up the first one it finds. + This also applies to cygwin1.dll and the main-executable (DLL_SELF). */ + dll *d = (type != DLL_LOAD) ? dlls.find_by_modname (modname) : dlls[ntname]; if (d) { /* We only get here in the forkee. */ @@ -339,7 +340,8 @@ dll_list::alloc (HINSTANCE h, per_process *p, dll_type type) d->modname = d->ntname + (modname - ntname); d->handle = h; d->count = 0; /* Reference counting performed in dlopen/dlclose. */ - d->has_dtors = true; + /* DLL_SELF dtors (main-executable, cygwin1.dll) are run elsewhere */ + d->has_dtors = type != DLL_SELF; d->p = p; d->ndeps = 0; d->deps = NULL; @@ -526,7 +528,7 @@ dll_list::find (void *retaddr) dll *d = &start; while ((d = d->next)) - if (d->handle == h) + if (d->type != DLL_SELF && d->handle == h) break; return d; } @@ -566,11 +568,22 @@ dll_list::detach (void *retaddr) void dll_list::init () { + track_self (); + /* Walk the dll chain, initializing each dll */ dll *d = &start; dll_global_dtors_recorded = d->next != NULL; while ((d = d->next)) - d->init (); + if (d->type != DLL_SELF) /* linked and early loaded dlls */ + d->init (); +} + +void +dll_list::track_self () +{ + /* for cygwin1.dll and main-executable: maintain hardlinks only */ + alloc (cygwin_hmodule, user_data, DLL_SELF); + main_executable = alloc (GetModuleHandle (NULL), user_data, DLL_SELF); } #define A64K (64 * 1024) @@ -637,7 +650,7 @@ dll_list::reserve_space () /* Reload DLLs after a fork. Iterates over the list of dynamically loaded DLLs and attempts to load them in the same place as they were loaded in the - parent. */ + parent. Updates main-executable and cygwin1.dll tracking. */ void dll_list::load_after_fork (HANDLE parent) { @@ -647,6 +660,7 @@ dll_list::load_after_fork (HANDLE parent) in_load_after_fork = true; if (reload_on_fork) load_after_fork_impl (parent, dlls.istart (DLL_LOAD), 0); + track_self (); in_load_after_fork = false; } diff --git a/winsup/cygwin/dll_init.h b/winsup/cygwin/dll_init.h index 4897c420f..369fc5427 100644 --- a/winsup/cygwin/dll_init.h +++ b/winsup/cygwin/dll_init.h @@ -40,6 +40,7 @@ struct per_module typedef enum { DLL_NONE, + DLL_SELF, /* main-program.exe, cygwin1.dll */ DLL_LINK, DLL_LOAD, DLL_ANY @@ -75,6 +76,8 @@ struct dll class dll_list { + void track_self (); + dll *end; dll *hold; dll_type hold_type; @@ -94,6 +97,7 @@ public: return nt_max_path_buffer; } + dll *main_executable; dll start; int loaded_dlls; int reload_on_fork; diff --git a/winsup/cygwin/fork.cc b/winsup/cygwin/fork.cc index c78e5cf3b..adcd1d7ad 100644 --- a/winsup/cygwin/fork.cc +++ b/winsup/cygwin/fork.cc @@ -175,7 +175,7 @@ frok::child (volatile char * volatile here) if (fixup_shms_after_fork ()) api_fatal ("recreate_shm areas after fork failed"); - /* load dynamic dlls, if any */ + /* load dynamic dlls, if any, re-track main-executable and cygwin1.dll */ dlls.load_after_fork (hParent); cygheap->fdtab.fixup_after_fork (hParent); @@ -310,11 +310,20 @@ frok::parent (volatile char * volatile stack_here) while (1) { + PCWCHAR forking_progname = NULL; + if (dlls.main_executable) + forking_progname = dll_list::buffered_shortname + (dlls.main_executable->ntname); + if (!forking_progname || !*forking_progname) + forking_progname = myself->progname; + syscall_printf ("CreateProcessW (%W, %W, 0, 0, 1, %y, 0, 0, %p, %p)", - myself->progname, myself->progname, c_flags, &si, &pi); + forking_progname, myself->progname, c_flags, &si, &pi); hchild = NULL; - rc = CreateProcessW (myself->progname, /* image to run */ + /* cygwin1.dll may reuse the forking_progname buffer, even + in case of failure: don't reuse forking_progname later */ + rc = CreateProcessW (forking_progname, /* image to run */ GetCommandLineW (), /* Take same space for command line as in parent to make sure child stack is allocated -- 2.43.5