Commit Graph

13 Commits

Author SHA1 Message Date
Corinna Vinschen 7097b05eda Cygwin: select: revamp non-polling code for signalfd
Rather than waiting for signalfd_select_wait in a thread, which is racy,
create a global event "my_pendingsigs_evt" which is set and reset by
wait_sig depending only on the fact if blocked signals are pending or not.

This in turn allows to WFMO on this event in select as soon as signalfds
are present in the read descriptor set.  Select's peek and verify
will then check if one of the present signalfds is affected.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2019-08-18 14:02:01 +02:00
Corinna Vinschen f7566c83c6 Cygwin: tlsoffsets64.h: regenerate
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2019-01-15 12:25:12 +01:00
Corinna Vinschen f42776fa78 Cygwin: signalfd: implement non-polling select
Allow the signal thread to recognize we're called in consequence of
select on a signalfd.  If the signal is part of the wait mask, don't
call any signal handler and don't remove the signal from the queue,
so a subsequent read (or sigwaitinfo/sigtimedwait) still gets the
signal.  Instead, just signal the event object at
_cygtls::signalfd_select_wait for the thread running select.

The addition of signalfd_select_wait to _cygtls unearthed the alignment
problem of the context member again.  To make sure this doesn't get lost,
improve the related comment in the header file so that this (hopefully)
doesn't get lost (again).

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2019-01-14 17:19:37 +01:00
Corinna Vinschen 2cd7eb7f60 Fix original stack when running signal handler on alternate stack
* autoload.cc (SetThreadStackGuarantee): Import.
        * cygtls.h (struct _cygtls): Replace thread_context with a ucontext_t
        called context.
        * exceptions.cc (exception::handle): Exit from process via signal_exit
        in case sig_send returns from handling a stack overflow SIGSEGV.
        Explain why.
        (dumpstack_overflow_wrapper): Thread wrapper to create a stackdump
        from another thread.
        (signal_exit): Fix argument list to reflect three-arg signal handler.
        In case we have to create a stackdump for a stack overflow condition,
        do so from a separate thread.  Explain why.
        (sigpacket::process): Don't run signal_exit on alternate stack.
        (altstack_wrapper): Wrapper function to do stack correction when
        calling the signal handler on an alternate stack to handle a stack
        overflow.  Make sure to have lots of comments.
        (_cygtls::call_signal_handler): Drop local context variable to reduce
        stack pressure.  Use this->context instead.  Change inline assembler
        to call altstack_wrapper.
        (_cygtls::signal_debugger): Accommodate aforementioned change to
        struct _cygtls.
        * tlsoffset.h: Regenerate.
        * tlsoffset64.h: Regenerate.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2015-07-04 22:49:30 +02:00
Corinna Vinschen 22465796ed Preliminary infrastructure to implement alternate stack
* libc/include/sys/signal.h: Define SS_ONSTACK and SS_DISABLE
	unconditionally.
	(sigaltstack): Enable prototype on Cygwin.

	* common.din (sigaltstack): Export.
	* cygtls.cc (_cygtls::init_thread): Initialize altstack.
	* cygtls.h (__tlsstack_t): Rename from __stack_t to distinguish
	more clearly from stack_t.  Accommodate throughout.
	(_cygtls): Add altstack member.
	* exceptions.cc (exception::handle): Set SIGSEGV handler to SIG_DFL
	if we encounter a stack overflow, and no alternate stack has been
	defined.
	* include/cygwin/signal.h (MINSIGSTKSZ): Define
	(SIGSTKSZ): Define.
	(SA_ONSTACK): Define.
	* signal.cc (sigaltstack): New function.
	* tlsoffset.h: Regenerate.
	* tlsoffset64.h: Ditto.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2015-06-19 16:12:45 +02:00
Corinna Vinschen 3fb21f9143 Prepare to rename/reuse struct ucontext.
* cygtls.h (struct _cygtls): Convert thread_context to type CONTEXT.
	* exceptions.cc (_cygtls::signal_debugger): Use sizeof (CONTEXT) for
	size of CONTEXT copied for GDB's digestion.
	* include/cygwin/signal.h: Add a preliminary comment.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2015-04-23 21:57:07 +02:00
Corinna Vinschen 5578cc4b73 * cygtls.cc (_cygtls::remove): Revert previous patch.
*  cygtls.h (struct _local_storage): Move pathbufs back here.
	(class san/x86_64): Revert class.  Save and restore pathbufs counters
	only.
	(class san/i686): Revert saving and restoring pathbufs counters.
	(__try/x86_64): Add a san variable and call it's setup method.
	(__except/x86_64): Call san::leave to restore pathbufs counters.
	* gendef (_sigbe): Revert previous change.
	* thread.cc (verifyable_object_state): Remove gcc 4.7 workaround in
	forward declaration as well.
	* tls_pbuf.cc (tls_pbuf): Revert previous change.
	* tls_pbuf.h (class tmp_pathbuf): Accommodate reverting pathbufs to
	locals structure.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Regenerate.
2014-08-25 14:53:49 +00:00
Corinna Vinschen 3f3bd10104 * Throughout, use __try/__except/__endtry blocks, rather than myfault
handler.
	* cygtls.cc (_cygtls::remove): Accommodate the fact that pathbufs
	has been moved from _local_storage to _cygtls.
	* cygtls.h (class tls_pathbuf): Add comment to hint to gendef usage
	of counters.  Change type of counters to uint32_t for clarity.
	Remove _cygtls as friend class.
	(struct _local_storage): Move pathbufs from here...
	(struct _cygtls): ...to here, allowing to access it from _sigbe.
	(class san): Only define on 32 bit.  Remove errno, _c_cnt and _w_cnt
	members.
	(san::setup): Drop parameter.  Don't initialize removed members.
	(san::leave): Don't set removed members.
	(class myfault): Only define on 32 bit.
	(myfault::faulted): Only keep implementation not taking any parameter.
	Drop argument in call to sebastian.setup.
	(__try/__leave/__except/__endtry): Implement to support real SEH.  For
	now stick to SJLJ on 32 bit.
	* dcrt0.cc (dll_crt0_0): Drop 64 bit call to
	exception::install_myfault_handler.
	* exception.h (exception_handler): Define with EXCEPTION_DISPOSITION
	as return type.
	(PDISPATCHER_CONTEXT): Define as void * on 32 bit.  Define as pointer
	to _DISPATCHER_CONTEXT on 64 bit.
	(class exception): Define separately for 32 and 64 bit.
	(exception::myfault): Add handler for myfault SEH handling on 64 bit.
	(exception::exception): Fix mangled method name to account for change
	in type of last parameter.
	(exception::install_myfault_handler): Remove.
	* exceptions.cc (exception::myfault_handle): Remove.
	(exception::myfault): New SEH handler for 64 bit.
	* gendef (_sigbe): Set tls_pathbuf counters to 0 explicitely when
	returning to the caller.
	* ntdll.h: Move a comment to a better place.
	(struct _SCOPE_TABLE): Define on 64 bit.
	* thread.cc (verifyable_object_isvalid): Remove gcc 4.7 workaround.
	* tls_pbuf.cc (tls_pbuf): Fix to accommodate new place of pathbufs.
	(tls_pathbuf::destroy): Change type of loop variables to uint32_t.
	* tls_pbuf.h (class tmp_pathbuf): Change type of buffer counters to
	uint32_t.  Accommodate new place of pathbufs.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Regenerate.
2014-08-22 09:21:33 +00:00
Corinna Vinschen 7ae3e6b3d4 * cygtls.h (TP_NUM_C_BUFS): Raise to 50 to allow SYMLOOP_MAX recursions
path_conv <-> normalize_posix_path, plus a bit of buffer.
	(TP_NUM_W_BUFS): Ditto.
	(class san): Change type of _c_cnt and _w_cnt to unsigned.
	* path.cc (normalize_posix_path): Guard recursion into path_conv
	against tmp_pathbuf overflow.  Generate normalized path in call to
	path_conv.  If the path is valid, replace dst with the normalized_path
	from path_conv call.  Add comment to explain why we're doing this.
	* tls_pbuf.cc (tls_pathbuf::destroy): Only free buffers until the
	first buffer pointer is NULL.
	(tmp_pathbuf::c_get): Simplify error message.
	(tmp_pathbuf::w_get): Ditto.
	* tls_pbuf.h (class tmp_pathbuf): Change type of c_buf_old and w_buf_old
	to unsigned.
	(tmp_pathbuf::check_usage): New inline method to check if we have
	enough tmp_pathbuf buffers left to call a function using tmp_pathbuf
	buffers.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Regenerate.
2014-04-18 14:29:49 +00:00
Corinna Vinschen 29b7313d22 * cygheap.h (enum cygheap_pwdgrp::cache_t): Remove.
(cygheap_pwdgrp::caching): Convert to bool.
	(cygheap_pwdgrp::pwd_cache): Add cygserver member.
	(cygheap_pwdgrp::grp_cache): Ditto.
	(cygheap_pwdgrp::nss_db_caching): Drop.
	(cygheap_pwdgrp::nss_db_full_caching): Drop.
	(cygheap_pwdgrp::nss_cygserver_caching): New method.
	(cygheap_pwdgrp::nss_disable_cygserver_caching): New method.
	* cygserver.h (client_request::request_code_t): Add
	CYGSERVER_REQUEST_PWDGRP.
	* cygserver_pwdgrp.h: New file.
	* cygtls.h (struct _local_storage): Remove pwbuf and grbuf members.
	* grp.cc (pwdgrp::prep_tls_grbuf): Drop.
	(internal_getgrsid): Handle cygserver caching and rearrange to check
	the caches first.
	(internal_getgrnam): Ditto.
	(internal_getgrgid): Ditto.
	(gr_ent::enumerate_caches): Handle cygserver cache.
	* passwd.cc (pwdgrp::prep_tls_pwbuf): Drop.
	(internal_getpwsid): Handle cygserver caching and rearrange to check
	the caches first.
	(internal_getpwnam): Ditto.
	(internal_getpwuid): Ditto.
	(pw_ent::enumerate_caches): Handle cygserver cache.
	* pwdgrp.h (pwdgrp::add_account_from_cygserver): New method declaration.
	(pwdgrp::fetch_account_from_cygserver): New method declaration.
	(pwdgrp::prep_tls_pwbuf): Drop declaration.
	(pwdgrp::prep_tls_grbuf): Drop declaration.
	(pwdgrp::add_user_from_cygserver): New inline methods.
	(pwdgrp::add_group_from_cygserver): New inline methods.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Regenerate.
	* uinfo.cc (internal_getlogin): Call internal_getgroups if cygserver
	caching is not available.
	(cygheap_pwdgrp::init): Initialize pwd_cache.cygserver and
	grp_cache.cygserver.  Set caching to true.
	(cygheap_pwdgrp::nss_init_line): Drop db_cache handling entirely.
	(pwdgrp::add_account_from_windows): Drop no caching handling.
	(client_request_pwdgrp::client_request_pwdgrp): New method.
	(pwdgrp::fetch_account_from_cygserver): New method.
	(pwdgrp::add_account_from_cygserver): New method.

	* fhandler_disk_file.cc (fhandler_base::fstat_helper): Fix formatting.
	* include/sys/cygwin.h: Ditto.
2014-03-12 17:36:56 +00:00
Corinna Vinschen a8cf6887a2 * autoload.cc (ldap_abandon): Import.
(ldap_result): Import.
	(ldap_searchW): Import.
	(NetGroupEnum): Import.
	(NetLocalGroupEnum): Import.
	(NetUserEnum): Import.
	* cygheap.h (class cygheap_pwdgrp): Add members enums and enum_tdoms.
	(cygheap_pwdgrp::nss_db_enums): New inline method.
	(cygheap_pwdgrp::nss_db_enum_tdoms): Ditto.
	* cygtls.h (struct _local_storage): Drop unused members pw_pos and
	grp_pos.
	* grp.cc (grent): New static variable of class gr_ent.
	(gr_ent::enumerate_caches): New method.
	(gr_ent::enumerate_local): New method.
	(gr_ent::getgrent): New method.
	(setgrent): Call gr_ent method.
	(getgrent32): Ditto.
	(endgrent): Ditto.
	* ldap.cc (sid_attr): Rename from nfs_attr.
	(cyg_ldap::close): Abandon still running asynchronous search.
	(cyg_ldap::fetch_ad_account): Reduce filter buffer size.
	(cyg_ldap::enumerate_ad_accounts): New method.
	(cyg_ldap::next_account): New method.
	(cyg_ldap::fetch_posix_offset_for_domain): Reduce filter buffer size.
	(cyg_ldap::fetch_unix_sid_from_ad): Ditto.  Fix return value in case
	no value has been read.
	(cyg_ldap::fetch_unix_name_from_rfc2307): Reduce filter buffer size.
	* ldap.h (class cyg_ldap): Add msg_id member.
	(cyg_ldap::enumerate_ad_accounts): Declare.
	(cyg_ldap::next_account): Declare:
	* passwd.cc (pwent): New static variable of class pw_ent.
	(pg_ent::clear_cache): New method.
	(pg_ent::setent): New method.
	(pg_ent::getent): New method.
	(pg_ent::endent): New method.
	(pg_ent::enumerate_file): New method.
	(pg_ent::enumerate_builtin): New method.
	(pg_ent::enumerate_sam): New method.
	(pg_ent::enumerate_ad): New method.
	(pw_ent::enumerate_caches): New method.
	(pw_ent::enumerate_local): New method.
	(pw_ent::getpwent): New method.
	(setpwent): Call pw_ent method.
	(getpwent): Ditto.
	(endpwent): Ditto.
	* pwdgrp.h (class pwdgrp): Define pg_ent, pw_ent and gr_ent as friend
	classes.
	(pwdgrp::add_account_post_fetch): Declare with extra bool parameter.
	(pwdgrp::file_attr): New inline method.
	(enum nss_enum_t): Define.
	(class pg_ent): Define.
	(class pw_ent): Define.
	(class gr_ent): Define.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Ditto.
	* uinfo.cc (cygheap_pwdgrp::init): Initialize enums and enum_tdoms.
	(cygheap_pwdgrp::nss_init_line): Fix typo in preceeding comment.
	Handle new "db_enum" keyword.
	(pwdgrp::add_account_post_fetch): Take additional `bool lock' parameter
	and acquire pglock before adding element to array if lock is true.
	(pwdgrp::add_account_from_file): Call add_account_post_fetch with lock
	set to true.
	(pwdgrp::add_account_from_windows): Ditto in case of caching.
	(pwdgrp::fetch_account_from_windows): Handle builtin aliases only
	known to the domain controller.  Only call NetLocalGroupGetInfo for
	aliases.
2014-02-17 15:36:33 +00:00
Corinna Vinschen 1ca20a1cd2 Introduce reading passwd/group entries from SAM/AD. Introduce
/etc/nsswitch.conf file to configure it.
	* Makefile.in (DLL_OFILES): Add ldap.o.
	* autoload.cc: Import ldap functions from wldap32.dll.
	(DsEnumerateDomainTrustsW): Import.
	(NetGroupGetInfo): Import.
	* cygheap.h (class cygheap_domain_info): New class to keep global
	domain info.
	(class cygheap_pwdgrp): New class to keep passwd/group caches and
	configuration info from /etc/nssswitch.conf.
	(struct init_cygheap): Add cygheap_domain_info member "dom" and
	cygheap_pwdgrp member "pg".
	* cygtls.h (struct _local_storage): Remove unused member "res".
	Rearrange slightly, Add members pwbuf and grbuf to implement non-caching
	passwd/group fetching from SAM/AD.  Make pw_pos and pw_pos unsigned.
	* fhandler_disk_file.cc (fhandler_base::fstat_by_nfs_ea): Add RFC 2307
	uid/gid mapping.
	* fhandler_process.cc: Drop including pwdgrp.h.
	* fhandler_procsysvipc.cc: Ditto.
	* fhandler_registry.cc (fhandler_registry::fstat): Set key uid/gid
	to ILLEGAL_UID/ILLEGAL_GID rather than UNKNOWN_UID/UNKNOWN_GID.
	* grp.cc (group_buf): Drop.
	(gr): Drop.
	(pwdgrp::parse_group): Fill pg_grp.
	(pwdgrp::read_group): Remove.
	(pwdgrp::init_grp): New method.
	(pwdgrp::prep_tls_grbuf): New method.
	(pwdgrp::find_group): New methods.
	(internal_getgrsid): Convert to call new pwdgrp methods.
	(internal_getgrnam): Ditto.
	(internal_getgrgid): Ditto.
	(getgrgid_r): Drop 2nd parameter from internal_getgrgid call.
	(getgrgid32): Ditto.
	(getgrnam_r): Ditto for internal_getgrnam.
	(getgrnam32): Ditto.
	(getgrent32): Convert to call new pwdgrp methods.
	(internal_getgrent): Remove.
	(internal_getgroups): Simplify, especially drop calls to
	internal_getgrent.
	* ldap.cc: New file implementing cyg_ldap class for LDAP access to AD
	and RFC 2307 server.
	* ldap.h: New header, declaring cyg_ldap class.
	* passwd.cc (passwd_buf): Drop.
	(pr): Drop.
	(pwdgrp::parse_passwd): Fill pg_pwd.
	(pwdgrp::read_passwd): Remove.
	(pwdgrp::init_pwd): New method.
	(pwdgrp::prep_tls_pwbuf): New method.
	(find_user): New methods.
	(internal_getpwsid): Convert to call new pwdgrp methods.
	(internal_getpwnam): Ditto.
	(internal_getpwuid): Ditto.
	(getpwuid32): Drop 2nd parameter from internal_getpwuid call.
	(getpwuid_r): Ditto.
	(getpwnam): Ditto for internal_getpwnam.
	(getpwnam_r): Ditto.
	(getpwent): Convert to call new pwdgrp methods.
	* path.cc (class etc): Remove all methods.
	* path.h (class etc): Drop.
	* pinfo.cc (pinfo_basic::pinfo_basic): Set gid to ILLEGAL_GID rather
	than UNKNOWN_GID.
	(pinfo_init): Ditto.
	* pwdgrp.h (internal_getpwnam): Drop 2nd parameter from declaration.
	(internal_getpwuid): Ditto.
	(internal_getgrgid): Ditto.
	(internal_getgrnam): Ditto.
	(internal_getgrent): Drop declaration.
	(enum fetch_user_arg_type_t): New type.
	(struct fetch_user_arg_t): New type.
	(struct pg_pwd): New type.
	(struct pg_grp): New type.
	(class pwdgrp): Rework to provide functions for file and db requests
	and caching.
	(class ugid_cache_t): New class to provide RFC 2307 uid map caching.
	(ugid_cache): Declare.
	* sec_acl.cc: Drop including pwdgrp.h.
	* sec_auth.cc: Drop including dsgetdc.h and pwdgrp.h.
	(get_logon_server): Convert third parameter to ULONG flags argument
	to allow arbitrary flags values in DsGetDcNameW call and change calls
	to this function throughout.  Use cached account domain name rather
	than calling GetComputerNameW.
	(get_unix_group_sidlist): Remove.
	(get_server_groups): Drop call to get_unix_group_sidlist.
	(verify_token): Rework token group check without calling
	internal_getgrent.
	* sec_helper.cc (cygpsid::pstring): New methods, like string() but
	return pointer to end of string.
	(cygsid::getfromstr): Add wide character implementation.
	(get_sids_info): Add RFC 2307 uid/gid mapping for Samba shares.
	* security.cc: Drop including pwdgrp.h.
	* security.h (DEFAULT_UID): Remove.
	(UNKNOWN_UID): Remove.
	(UNKNOWN_GID): Remove.
	(uinfo_init): Move here from winsup.h.
	(ILLEGAL_UID): Ditto.
	(ILLEGAL_GID): Ditto.
	(UNIX_POSIX_OFFSET): Define.  Add lengthy comment.
	(UNIX_POSIX_MASK): Ditto.
	(MAP_UNIX_TO_CYGWIN_ID): Ditto.
	(ILLEGAL_UID16): Move here from winsup.h.
	(ILLEGAL_GID16): Ditto.
	(uid16touid32): Ditto.
	(gid16togid32): Ditto.
	(sid_id_auth): New convenience macro for SID component access.
	(sid_sub_auth_count): Ditto.
	(sid_sub_auth): Ditto.
	(sid_sub_auth_rid): Ditto.
	(cygpsid::pstring): Declare.
	(cygsid::getfromstr): Declare wide character variant.
	(cygsid::operator=): Ditto.
	(cygsid::operator*=): Ditto.
	(get_logon_server): Change declaration according to source code.
	* setlsapwd.cc (setlsapwd): Drop 2nd parameter from internal_getpwnam
	call.
	* shared.cc (memory_init): Call cygheap->pg.init in first process.
	* syscalls.cc: Drop including pwdgrp.h.
	* tlsoffsets.h: Regenerate.
	* tlsoffsets64.h: Ditto.
	* uinfo.cc (internal_getlogin): Drop gratuitious internal_getpwuid
	call.  Fix debug output.  Overwrite user gid in border case of a
	missing passwd file while a group file exists.
	(pwdgrp::add_line): Allocate memory on cygheap.
	(pwdgrp::load): Remove.
	(ugid_cache): Define.
	(cygheap_pwdgrp::init): New method.
	(cygheap_pwdgrp::nss_init_line): New method.
	(cygheap_pwdgrp::_nss_init): New method.
	(cygheap_domain_info::init): New method.
	(logon_sid): Define.
	(get_logon_sid): New function.
	(pwdgrp::add_account_post_fetch): New method.
	(pwdgrp::add_account_from_file): New methods.
	(pwdgrp::add_account_from_windows): New methods.
	(pwdgrp::check_file): New method.
	(pwdgrp::fetch_account_from_line): New method.
	(pwdgrp::fetch_account_from_file): New method.
	(pwdgrp::fetch_account_from_windows): New method.
	* winsup.h: Move aforementioned macros and declarations to security.h.
2014-02-09 19:44:56 +00:00
Corinna Vinschen 61522196c7 * Merge in cygwin-64bit-branch. 2013-04-23 09:44:36 +00:00