From c14dcd878afe5227f92ad787974c94d2870b9bac Mon Sep 17 00:00:00 2001 From: corinna Date: Tue, 5 Dec 2006 10:59:20 +0000 Subject: [PATCH] * dcrt0.cc (get_cygwin_startup_info): Change zeros to DWORD array. Expect first DWORD in child_info struct being set to non-zero if wincap.needs_count_in_si_lpres2 is set. Add comment to explain why. * fork.cc (frok::parent): Set ch.zero[0] to a sensible count value if wincap.needs_count_in_si_lpres2 is set. * spawn.cc (spawn_guts): Ditto. Add filler bytes after ch on stack to accomodate needs_count_in_si_lpres2. * wincap.h: Define needs_count_in_si_lpres2 throughout. * wincap.cc: Ditto. --- winsup/cygwin/ChangeLog | 12 ++++++++++++ winsup/cygwin/dcrt0.cc | 28 +++++++++++++++++++++++++++- winsup/cygwin/fork.cc | 5 +++++ winsup/cygwin/spawn.cc | 13 ++++++++++++- winsup/cygwin/wincap.cc | 13 +++++++++++++ winsup/cygwin/wincap.h | 2 ++ 6 files changed, 71 insertions(+), 2 deletions(-) diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog index 8e7781469a..8da34acaa6 100644 --- a/winsup/cygwin/ChangeLog +++ b/winsup/cygwin/ChangeLog @@ -1,3 +1,15 @@ +2006-12-04 Corinna Vinschen + + * dcrt0.cc (get_cygwin_startup_info): Change zeros to DWORD array. + Expect first DWORD in child_info struct being set to non-zero if + wincap.needs_count_in_si_lpres2 is set. Add comment to explain why. + * fork.cc (frok::parent): Set ch.zero[0] to a sensible count value + if wincap.needs_count_in_si_lpres2 is set. + * spawn.cc (spawn_guts): Ditto. Add filler bytes after ch on stack + to accomodate needs_count_in_si_lpres2. + * wincap.h: Define needs_count_in_si_lpres2 throughout. + * wincap.cc: Ditto. + 2006-11-29 Corinna Vinschen * dir.cc (mkdir): Check last path component for "..". diff --git a/winsup/cygwin/dcrt0.cc b/winsup/cygwin/dcrt0.cc index 2a7b672113..023f7682c6 100644 --- a/winsup/cygwin/dcrt0.cc +++ b/winsup/cygwin/dcrt0.cc @@ -590,10 +590,36 @@ child_info * get_cygwin_startup_info () { STARTUPINFO si; - char zeros[sizeof (child_proc_info->zero)] = {0}; + DWORD zeros[sizeof (child_proc_info->zero) + / sizeof (child_proc_info->zero[0])] = {0}; GetStartupInfo (&si); child_info *res = (child_info *) si.lpReserved2; + + /* It appears that when running under WOW64 on Vista 64, the first DWORD + value in the datastructure lpReserved2 is pointing to (zero[0] in + Cygwin), has to reflect the size of that datastructure as used in the + Microsoft C runtime (a count value, counting the number of elements in + two subsequent arrays, BYTE[count and HANDLE[count]), even though the C + runtime isn't used. Otherwise, if zero[0] is 0 or too small, the + datastructure gets overwritten. + + This seems to be a bug in Vista's WOW64, which apparently copies the + lpReserved2 datastructure not using the cbReserved2 size information, + but using the information given in the first DWORD within lpReserved2 + instead. Funny enough, 32 bit Vista doesn't care if zero[0] is 0 or a + non-0 count value, while older versions of Windows might crash if + zero[0] is set to a non-zero value, as observed at least on XP 64. + + exec/spawn as well as fork write an appropriate value into zero[0] now, + depending on the wincap.needs_count_in_si_lpres2 flag. The value is + sizeof (child_info_*) / 5 which results in a count which covers the + full datastructure, plus not more than 4 extra bytes. This is ok as + long as the child_info structure is cosily stored within a bigger + datastructure. */ + if (wincap.needs_count_in_si_lpres2 ()) + zeros[0] = si.cbReserved2 / 5; + if (si.cbReserved2 < EXEC_MAGIC_SIZE || !res || memcmp (res->zero, zeros, sizeof (res->zero)) != 0) res = NULL; diff --git a/winsup/cygwin/fork.cc b/winsup/cygwin/fork.cc index ed85e74cf0..cc5beceb73 100644 --- a/winsup/cygwin/fork.cc +++ b/winsup/cygwin/fork.cc @@ -280,9 +280,14 @@ frok::parent (void *stack_here) memset (&si, 0, sizeof (si)); si.cb = sizeof (STARTUPINFO); + si.lpReserved2 = (LPBYTE) &ch; si.cbReserved2 = sizeof (ch); + /* See comment in dcrt0.cc, function get_cygwin_startup_info. */ + if (wincap.needs_count_in_si_lpres2 ()) + ch.zero[0] = sizeof (ch) / 5; + syscall_printf ("CreateProcess (%s, %s, 0, 0, 1, %p, 0, 0, %p, %p)", myself->progname, myself->progname, c_flags, &si, &pi); bool locked = __malloc_lock (); diff --git a/winsup/cygwin/spawn.cc b/winsup/cygwin/spawn.cc index d1750f744a..12418df926 100644 --- a/winsup/cygwin/spawn.cc +++ b/winsup/cygwin/spawn.cc @@ -298,7 +298,13 @@ spawn_guts (const char * prog_arg, const char *const *argv, pthread_cleanup_push (do_cleanup, (void *) &cleanup); av newargv; linebuf one_line; - child_info_spawn ch; + /* Allocate slightly bigger for call to CreateProcess to accomodate + needs_count_in_si_lpres2. */ + struct { + child_info_spawn ch; + char filler[4]; + } _ch; +#define ch _ch.ch char *envblock = NULL; path_conv real_path; @@ -481,6 +487,10 @@ spawn_guts (const char * prog_arg, const char *const *argv, si.lpReserved2 = (LPBYTE) &ch; si.cbReserved2 = sizeof (ch); + /* See comment in dcrt0.cc, function get_cygwin_startup_info. */ + if (wincap.needs_count_in_si_lpres2 ()) + ch.zero[0] = sizeof (ch) / 5; + /* When ruid != euid we create the new process under the current original account and impersonate in child, this way maintaining the different effective vs. real ids. @@ -724,6 +734,7 @@ out: free (envblock); pthread_cleanup_pop (1); return (int) res; +#undef ch } extern "C" int diff --git a/winsup/cygwin/wincap.cc b/winsup/cygwin/wincap.cc index 85405bae1e..2df00624fc 100644 --- a/winsup/cygwin/wincap.cc +++ b/winsup/cygwin/wincap.cc @@ -70,6 +70,7 @@ static NO_COPY wincaps wincap_unknown = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_95 = { @@ -131,6 +132,7 @@ static NO_COPY wincaps wincap_95 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_95osr2 = { @@ -192,6 +194,7 @@ static NO_COPY wincaps wincap_95osr2 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_98 = { @@ -253,6 +256,7 @@ static NO_COPY wincaps wincap_98 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_98se = { @@ -314,6 +318,7 @@ static NO_COPY wincaps wincap_98se = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_me = { @@ -375,6 +380,7 @@ static NO_COPY wincaps wincap_me = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_nt3 = { @@ -436,6 +442,7 @@ static NO_COPY wincaps wincap_nt3 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:true, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_nt4 = { @@ -497,6 +504,7 @@ static NO_COPY wincaps wincap_nt4 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:true, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_nt4sp4 = { @@ -558,6 +566,7 @@ static NO_COPY wincaps wincap_nt4sp4 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:true, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_2000 = { @@ -619,6 +628,7 @@ static NO_COPY wincaps wincap_2000 = { has_buggy_restart_scan:true, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:true, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_xp = { @@ -680,6 +690,7 @@ static NO_COPY wincaps wincap_xp = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_2003 = { @@ -741,6 +752,7 @@ static NO_COPY wincaps wincap_2003 = { has_buggy_restart_scan:false, has_mandatory_integrity_control:false, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:false, }; static NO_COPY wincaps wincap_vista = { @@ -802,6 +814,7 @@ static NO_COPY wincaps wincap_vista = { has_buggy_restart_scan:false, has_mandatory_integrity_control:true, needs_logon_sid_in_sid_list:false, + needs_count_in_si_lpres2:true, }; wincapc wincap __attribute__((section (".cygwin_dll_common"), shared)); diff --git a/winsup/cygwin/wincap.h b/winsup/cygwin/wincap.h index d40d12c1a2..2928f8d625 100644 --- a/winsup/cygwin/wincap.h +++ b/winsup/cygwin/wincap.h @@ -71,6 +71,7 @@ struct wincaps unsigned has_buggy_restart_scan : 1; unsigned has_mandatory_integrity_control : 1; unsigned needs_logon_sid_in_sid_list : 1; + unsigned needs_count_in_si_lpres2 : 1; }; class wincapc @@ -148,6 +149,7 @@ public: bool IMPLEMENT (has_buggy_restart_scan) bool IMPLEMENT (has_mandatory_integrity_control) bool IMPLEMENT (needs_logon_sid_in_sid_list) + bool IMPLEMENT (needs_count_in_si_lpres2) #undef IMPLEMENT }; -- 2.11.0