system/musl: update to latest version. fixes #444.

5 files changed, 39 insertions, 411 deletions

diff --git a/system/musl/APKBUILD b/system/musl/APKBUILD
index 735541e51..56fadc5e2 100644
--- a/system/musl/APKBUILD
+++ b/system/musl/APKBUILD
@@ -1,7 +1,8 @@
 # Maintainer: A. Wilcox <awilfox@adelielinux.org>
 pkgname=musl
-pkgver=1.2.0
-pkgrel=2
+pkgver=1.2.3_pre1
+pkgrel=0
+pkgdate=20211129
 pkgdesc="System library (libc) implementation"
 url="https://www.musl-libc.org/"
 arch="all"
@@ -21,18 +22,17 @@ nolibc) ;;
 	triggers="$pkgname-utils.trigger=/etc/ld.so.conf.d"
 	;;
 esac
-source="https://musl.libc.org/releases/$pkgname-$pkgver.tar.gz
+source="https://distfiles.adelielinux.org/source/$pkgname-$pkgver-$pkgdate.tar.xz
 	amalgamation.patch
 	3001-make-real-lastlog-h.patch
 	handle-aux-at_base.patch
 	fgetspent_r.patch
-	threads_minus_1.patch
-	CVE-2020-28928.patch
 
 	ldconfig
 	getent.c
 	iconv.c
 	"
+builddir="$srcdir/$pkgname-$pkgver-$pkgdate"
 
 # secfixes:
 #   1.1.15-r4:
@@ -120,13 +120,11 @@ utils() {
 	install -D -m755 "$srcdir"/ldconfig "$subpkgdir"/sbin
 }
 
-sha512sums="58bd88189a6002356728cea1c6f6605a893fe54f7687595879add4eab283c8692c3b031eb9457ad00d1edd082cfe62fcc0eb5eb1d3bf4f1d749c0efa2a95fec1  musl-1.2.0.tar.gz
-f01ab92b9d385c15369c0bb7d95e1bc06a009c8851e363517d0ba1bae3fc2647af69fc2f363b5d962d376c5d9a1994b5728fd88ccbfff5f0d3d0970a02df1512  amalgamation.patch
+sha512sums="b8a9790a79571854a0a95cb4fcc2dcc9f705879fafdb9c3ec7088dd72649b60449a8370df9337a734af7198a39337684a7662d2ce411d284ca435ad597b900fc  musl-1.2.3_pre1-20211129.tar.xz
+f7b05d8c5f804ba3ad6998b3de5fa4d9dfceac4aca63dd67298c2d5f27cdd28a91eba74f6e428c258323da80635dd333bae2c47ff918894797cba92bd5700909  amalgamation.patch
 88ae443dbb8e0a4368235bdc3a1c5c7b718495afa75e06deb8e01becc76cb1f0d6964589e2204fc749c9c1b3190b8b9ac1ae2c0099cab8e2ce3ec877103d4332  3001-make-real-lastlog-h.patch
-6a7ff16d95b5d1be77e0a0fbb245491817db192176496a57b22ab037637d97a185ea0b0d19da687da66c2a2f5578e4343d230f399d49fe377d8f008410974238  handle-aux-at_base.patch
+1f4e9aea5a546015c75f77aa0dec10d56fc14831ccc15cf71ff27fc15ac5230ffeadb382ebe1c87c1ea07a462620e16ed01cd36252d997d1a9c2af11cb5c9ff3  handle-aux-at_base.patch
 ded41235148930f8cf781538f7d63ecb0c65ea4e8ce792565f3649ee2523592a76b2a166785f0b145fc79f5852fd1fb1729a7a09110b3b8f85cba3912e790807  fgetspent_r.patch
-68830961e297d9a499f3b609be84848ad5d3326a1af56e9e54a40ecd972c48da11532c51da572d45e0df3574d63191e7ae0d3a1b84a029365f8d00691de96952  threads_minus_1.patch
-343ac5e5365cf98a5d5b7bc192c671733fdba27f06b83484f1ac7647154228745415f62dd676029de538460f8b35e0a70ca453a0f8b73226ed1c420099b1cf90  CVE-2020-28928.patch
 cb71d29a87f334c75ecbc911becde7be825ab30d8f39fa6d64cb53812a7c9abaf91d9804c72540e5be3ddd3c84cfe7fd9632274309005cb8bcdf9a9b09b4b923  ldconfig
 378d70e65bcc65bb4e1415354cecfa54b0c1146dfb24474b69e418cdbf7ad730472cd09f6f103e1c99ba6c324c9560bccdf287f5889bbc3ef0bdf0e08da47413  getent.c
 9d42d66fb1facce2b85dad919be5be819ee290bd26ca2db00982b2f8e055a0196290a008711cbe2b18ec9eee8d2270e3b3a4692c5a1b807013baa5c2b70a2bbf  iconv.c"
diff --git a/system/musl/CVE-2020-28928.patch b/system/musl/CVE-2020-28928.patch
deleted file mode 100644
index cc668e149..000000000
--- a/system/musl/CVE-2020-28928.patch
+++ /dev/null
@@ -1,112 +0,0 @@
-From 3ab2a4e02682df1382955071919d8aa3c3ec40d4 Mon Sep 17 00:00:00 2001
-From: Rich Felker <dalias@aerifal.cx>
-Date: Thu, 19 Nov 2020 17:12:43 -0500
-Subject: [PATCH] rewrite wcsnrtombs to fix buffer overflow and other bugs
-
-the original wcsnrtombs implementation, which has been largely
-untouched since 0.5.0, attempted to build input-length-limiting
-conversion on top of wcsrtombs, which only limits output length. as
-best I recall, this choice was made out of a mix of disdain over
-having yet another variant function to implement (added in POSIX 2008;
-not standard C) and preference not to switch things around and
-implement the wcsrtombs in terms of the more general new function,
-probably over namespace issues. the strategy employed was to impose
-output limits that would ensure the input limit wasn't exceeded, then
-finish up the tail character-at-a-time. unfortunately, none of that
-worked correctly.
-
-first, the logic in the wcsrtombs loop was wrong in that it could
-easily get stuck making no forward progress, by imposing an output
-limit too small to convert even one character.
-
-the character-at-a-time loop that followed was even worse. it made no
-effort to ensure that the converted multibyte character would fit in
-the remaining output space, only that there was a nonzero amount of
-output space remaining. it also employed an incorrect interpretation
-of wcrtomb's interface contract for converting the null character,
-thereby failing to act on end of input, and remaining space accounting
-was subject to unsigned wrap-around. together these errors allow
-unbounded overflow of the destination buffer, controlled by input
-length limit and input wchar_t string contents.
-
-given the extent to which this function was broken, it's plausible
-that most applications that would have been rendered exploitable were
-sufficiently broken not to be usable in the first place. however, it's
-also plausible that common (especially ASCII-only) inputs succeeded in
-the wcsrtombs loop, which mostly worked, while leaving the wildly
-erroneous code in the second loop exposed to particular non-ASCII
-inputs.
-
-CVE-2020-28928 has been assigned for this issue.
----
- src/multibyte/wcsnrtombs.c | 46 ++++++++++++++++----------------------
- 1 file changed, 19 insertions(+), 27 deletions(-)
-
-diff --git a/src/multibyte/wcsnrtombs.c b/src/multibyte/wcsnrtombs.c
-index 676932b5..95e25e70 100644
---- a/src/multibyte/wcsnrtombs.c
-+++ b/src/multibyte/wcsnrtombs.c
-@@ -1,41 +1,33 @@
- #include <wchar.h>
-+#include <limits.h>
-+#include <string.h>
- 
- size_t wcsnrtombs(char *restrict dst, const wchar_t **restrict wcs, size_t wn, size_t n, mbstate_t *restrict st)
- {
--	size_t l, cnt=0, n2;
--	char *s, buf[256];
- 	const wchar_t *ws = *wcs;
--	const wchar_t *tmp_ws;
--
--	if (!dst) s = buf, n = sizeof buf;
--	else s = dst;
--
--	while ( ws && n && ( (n2=wn)>=n || n2>32 ) ) {
--		if (n2>=n) n2=n;
--		tmp_ws = ws;
--		l = wcsrtombs(s, &ws, n2, 0);
--		if (!(l+1)) {
--			cnt = l;
--			n = 0;
-+	size_t cnt = 0;
-+	if (!dst) n=0;
-+	while (ws && wn) {
-+		char tmp[MB_LEN_MAX];
-+		size_t l = wcrtomb(n<MB_LEN_MAX ? tmp : dst, *ws, 0);
-+		if (l==-1) {
-+			cnt = -1;
- 			break;
- 		}
--		if (s != buf) {
--			s += l;
-+		if (dst) {
-+			if (n<MB_LEN_MAX) {
-+				if (l>n) break;
-+				memcpy(dst, tmp, l);
-+			}
-+			dst += l;
- 			n -= l;
- 		}
--		wn = ws ? wn - (ws - tmp_ws) : 0;
--		cnt += l;
--	}
--	if (ws) while (n && wn) {
--		l = wcrtomb(s, *ws, 0);
--		if ((l+1)<=1) {
--			if (!l) ws = 0;
--			else cnt = l;
-+		if (!*ws) {
-+			ws = 0;
- 			break;
- 		}
--		ws++; wn--;
--		/* safe - this loop runs fewer than sizeof(buf) times */
--		s+=l; n-=l;
-+		ws++;
-+		wn--;
- 		cnt += l;
- 	}
- 	if (dst) *wcs = ws;
--- 
-2.25.4
-
diff --git a/system/musl/amalgamation.patch b/system/musl/amalgamation.patch
index 5918c3be6..5e273ce7f 100644
--- a/system/musl/amalgamation.patch
+++ b/system/musl/amalgamation.patch
@@ -8,14 +8,14 @@ index e9ca94cb..b39b12ee 100644
  #include <time.h>
  #include <errno.h>
 diff --git a/include/stdlib.h b/include/stdlib.h
-index 194c2033..5734b1f0 100644
+index b507ca33..5e14b07c 100644
 --- a/include/stdlib.h
 +++ b/include/stdlib.h
-@@ -39,14 +39,18 @@ void *malloc (size_t);
+@@ -41,14 +41,18 @@ void *malloc (size_t);
  void *calloc (size_t, size_t);
  void *realloc (void *, size_t);
  void free (void *);
-+#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L
++#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L || defined(_BSD_SOURCE) || defined(_GNU_SOURCE)
  void *aligned_alloc(size_t, size_t);
 +#endif
  
@@ -23,14 +23,14 @@ index 194c2033..5734b1f0 100644
  int atexit (void (*) (void));
  _Noreturn void exit (int);
  _Noreturn void _Exit (int);
-+#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L
++#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L || defined(_BSD_SOURCE) || defined(_GNU_SOURCE)
  int at_quick_exit (void (*) (void));
  _Noreturn void quick_exit (int);
 +#endif
  
  char *getenv (const char *);
  
-@@ -100,7 +104,6 @@ int posix_memalign (void **, size_t, size_t);
+@@ -102,7 +106,6 @@ int posix_memalign (void **, size_t, size_t);
  int setenv (const char *, const char *, int);
  int unsetenv (const char *);
  int mkstemp (char *);
@@ -38,7 +38,7 @@ index 194c2033..5734b1f0 100644
  char *mkdtemp (char *);
  int getsubopt (char **, char *const *, char **);
  int rand_r (unsigned *);
-@@ -138,6 +141,7 @@ void lcong48 (unsigned short [7]);
+@@ -140,6 +143,7 @@ void lcong48 (unsigned short [7]);
  #include <alloca.h>
  char *mktemp (char *);
  int mkstemps (char *, int);
@@ -59,10 +59,10 @@ index cdc67ef6..fd773896 100644
  struct itimerval {
  	struct timeval it_interval;
 diff --git a/include/time.h b/include/time.h
-index 5494df18..2412fe22 100644
+index 3d948372..deb4a450 100644
 --- a/include/time.h
 +++ b/include/time.h
-@@ -58,11 +58,14 @@ struct tm *gmtime (const time_t *);
+@@ -60,11 +60,14 @@ struct tm *gmtime (const time_t *);
  struct tm *localtime (const time_t *);
  char *asctime (const struct tm *);
  char *ctime (const time_t *);
@@ -79,7 +79,7 @@ index 5494df18..2412fe22 100644
  
  #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
   || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
-@@ -137,7 +140,10 @@ __REDIR(mktime, __mktime64);
+@@ -139,7 +142,10 @@ __REDIR(mktime, __mktime64);
  __REDIR(gmtime, __gmtime64);
  __REDIR(localtime, __localtime64);
  __REDIR(ctime, __ctime64);
@@ -91,10 +91,10 @@ index 5494df18..2412fe22 100644
   || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
   || defined(_BSD_SOURCE)
 diff --git a/include/unistd.h b/include/unistd.h
-index 7bcbff94..6fd67160 100644
+index ee2dbe8a..ed75e578 100644
 --- a/include/unistd.h
 +++ b/include/unistd.h
-@@ -33,16 +33,23 @@ extern "C" {
+@@ -35,16 +35,23 @@ extern "C" {
  #include <bits/alltypes.h>
  
  int pipe(int [2]);
@@ -121,7 +121,7 @@ index 7bcbff94..6fd67160 100644
  ssize_t read(int, void *, size_t);
  ssize_t write(int, const void *, size_t);
  ssize_t pread(int, void *, size_t, off_t);
-@@ -202,8 +209,6 @@ ssize_t copy_file_range(int, off_t *, int, off_t *, size_t, unsigned);
+@@ -206,8 +213,6 @@ pid_t gettid(void);
  #define off64_t off_t
  #endif
  
@@ -130,7 +130,7 @@ index 7bcbff94..6fd67160 100644
  #define _XOPEN_VERSION          700
  #define _XOPEN_UNIX             1
  #define _XOPEN_ENH_I18N         1
-@@ -276,6 +281,7 @@ ssize_t copy_file_range(int, off_t *, int, off_t *, size_t, unsigned);
+@@ -280,6 +285,7 @@ pid_t gettid(void);
  #define _PC_ALLOC_SIZE_MIN	18
  #define _PC_SYMLINK_MAX	19
  #define _PC_2_SYMLINKS	20
@@ -138,7 +138,7 @@ index 7bcbff94..6fd67160 100644
  
  #define _SC_ARG_MAX	0
  #define _SC_CHILD_MAX	1
-@@ -419,6 +425,7 @@ ssize_t copy_file_range(int, off_t *, int, off_t *, size_t, unsigned);
+@@ -423,6 +429,7 @@ pid_t gettid(void);
  #define _SC_XOPEN_STREAMS	246
  #define _SC_THREAD_ROBUST_PRIO_INHERIT	247
  #define _SC_THREAD_ROBUST_PRIO_PROTECT	248
@@ -146,7 +146,7 @@ index 7bcbff94..6fd67160 100644
  
  #define _CS_PATH	0
  #define _CS_POSIX_V6_WIDTH_RESTRICTED_ENVS	1
-@@ -461,6 +468,8 @@ ssize_t copy_file_range(int, off_t *, int, off_t *, size_t, unsigned);
+@@ -465,6 +472,8 @@ pid_t gettid(void);
  #define _CS_POSIX_V7_LPBIG_OFFBIG_LINTFLAGS	1147
  #define _CS_V6_ENV	1148
  #define _CS_V7_ENV	1149
@@ -208,18 +208,27 @@ index 3baaed32..04369596 100644
  
  	if (name >= sizeof(values)/sizeof(values[0]) || !values[name]) {
 diff --git a/src/locale/setlocale.c b/src/locale/setlocale.c
-index 2bc7b500..4a601eaf 100644
+index 360c4437..76dbfc37 100644
 --- a/src/locale/setlocale.c
 +++ b/src/locale/setlocale.c
-@@ -14,6 +14,8 @@ char *setlocale(int cat, const char *name)
+@@ -13,6 +13,8 @@ char *setlocale(int cat, const char *name)
  
  	if ((unsigned)cat > LC_ALL) return 0;
  
 +	if (name && (!strncmp(name, "VSX4L", 5))) return 0;
 +
- 	LOCK(lock);
+ 	LOCK(__locale_lock);
  
  	/* For LC_ALL, setlocale is required to return a string which
+diff --git a/src/malloc/posix_memalign.c b/src/malloc/posix_memalign.c
+index ad4d8f47..3318f86a 100644
+--- a/src/malloc/posix_memalign.c
++++ b/src/malloc/posix_memalign.c
+@@ -1,3 +1,4 @@
++#define _BSD_SOURCE
+ #include <stdlib.h>
+ #include <errno.h>
+ 
 diff --git a/src/misc/forkpty.c b/src/misc/forkpty.c
 index caf13adb..43494b96 100644
 --- a/src/misc/forkpty.c
@@ -331,7 +340,7 @@ index 5af59b80..3f61d278 100644
  	sigaction(SIGINT, &sa, &oldint);
  	sigaction(SIGQUIT, &sa, &oldquit);
 diff --git a/src/stdio/popen.c b/src/stdio/popen.c
-index 92cb57ee..70c5d6ec 100644
+index 3ec83394..58883b11 100644
 --- a/src/stdio/popen.c
 +++ b/src/stdio/popen.c
 @@ -1,3 +1,4 @@
@@ -387,7 +396,7 @@ index 40ea9c1c..e396da09 100644
  
  /* There is no other implemented value than TIME_UTC; all other values
 diff --git a/src/unistd/faccessat.c b/src/unistd/faccessat.c
-index 76bbd4c7..0b4564f9 100644
+index 557503eb..756a7bc4 100644
 --- a/src/unistd/faccessat.c
 +++ b/src/unistd/faccessat.c
 @@ -1,3 +1,4 @@
diff --git a/system/musl/handle-aux-at_base.patch b/system/musl/handle-aux-at_base.patch
index c16463824..697c82bbb 100644
--- a/system/musl/handle-aux-at_base.patch
+++ b/system/musl/handle-aux-at_base.patch
@@ -2,7 +2,7 @@ diff --git a/src/env/__init_tls.c b/src/env/__init_tls.c
 index b125eb1..616c6a6 100644
 --- a/src/env/__init_tls.c
 +++ b/src/env/__init_tls.c
-@@ -66,8 +66,10 @@ void *__copy_tls(unsigned char *mem)
+@@ -72,8 +72,10 @@ void *__copy_tls(unsigned char *mem)
  }
  
  #if ULONG_MAX == 0xffffffff
@@ -13,7 +13,7 @@ index b125eb1..616c6a6 100644
  typedef Elf64_Phdr Phdr;
  #endif
  
-@@ -77,15 +79,23 @@ extern const size_t _DYNAMIC[];
+@@ -82,15 +84,23 @@ extern const size_t _DYNAMIC[];
  static void static_init_tls(size_t *aux)
  {
  	unsigned char *p;
diff --git a/system/musl/threads_minus_1.patch b/system/musl/threads_minus_1.patch
deleted file mode 100644
index 05307d97c..000000000
--- a/system/musl/threads_minus_1.patch
+++ /dev/null
@@ -1,267 +0,0 @@
-https://www.openwall.com/lists/musl/2020/05/22/10
-
-From 4d5aa20a94a2d3fae3e69289dc23ecafbd0c16c4 Mon Sep 17 00:00:00 2001
-From: Rich Felker <dalias@aerifal.cx>
-Date: Fri, 22 May 2020 17:35:14 -0400
-Subject: [PATCH 1/4] reorder thread list unlink in pthread_exit after all
- locks
-
-since the backend for LOCK() skips locking if single-threaded, it's
-unsafe to make the process appear single-threaded before the last use
-of lock.
-
-this fixes potential unsynchronized access to a linked list via
-__dl_thread_cleanup.
----
- src/thread/pthread_create.c | 19 +++++++++++--------
- 1 file changed, 11 insertions(+), 8 deletions(-)
-
-diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
-index 5f491092..6a3b0c21 100644
---- a/src/thread/pthread_create.c
-+++ b/src/thread/pthread_create.c
-@@ -90,14 +90,7 @@ _Noreturn void __pthread_exit(void *result)
- 		exit(0);
- 	}
- 
--	/* At this point we are committed to thread termination. Unlink
--	 * the thread from the list. This change will not be visible
--	 * until the lock is released, which only happens after SYS_exit
--	 * has been called, via the exit futex address pointing at the lock. */
--	libc.threads_minus_1--;
--	self->next->prev = self->prev;
--	self->prev->next = self->next;
--	self->prev = self->next = self;
-+	/* At this point we are committed to thread termination. */
- 
- 	/* Process robust list in userspace to handle non-pshared mutexes
- 	 * and the detached thread case where the robust list head will
-@@ -121,6 +114,16 @@ _Noreturn void __pthread_exit(void *result)
- 	__do_orphaned_stdio_locks();
- 	__dl_thread_cleanup();
- 
-+	/* Last, unlink thread from the list. This change will not be visible
-+	 * until the lock is released, which only happens after SYS_exit
-+	 * has been called, via the exit futex address pointing at the lock.
-+	 * This needs to happen after any possible calls to LOCK() that might
-+	 * skip locking if libc.threads_minus_1 is zero. */
-+	libc.threads_minus_1--;
-+	self->next->prev = self->prev;
-+	self->prev->next = self->next;
-+	self->prev = self->next = self;
-+
- 	/* This atomic potentially competes with a concurrent pthread_detach
- 	 * call; the loser is responsible for freeing thread resources. */
- 	int state = a_cas(&self->detach_state, DT_JOINABLE, DT_EXITING);
--- 
-2.21.0
-
-From e01b5939b38aea5ecbe41670643199825874b26c Mon Sep 17 00:00:00 2001
-From: Rich Felker <dalias@aerifal.cx>
-Date: Thu, 21 May 2020 23:32:45 -0400
-Subject: [PATCH 2/4] don't use libc.threads_minus_1 as relaxed atomic for
- skipping locks
-
-after all but the last thread exits, the next thread to observe
-libc.threads_minus_1==0 and conclude that it can skip locking fails to
-synchronize with any changes to memory that were made by the
-last-exiting thread. this can produce data races.
-
-on some archs, at least x86, memory synchronization is unlikely to be
-a problem; however, with the inline locks in malloc, skipping the lock
-also eliminated the compiler barrier, and caused code that needed to
-re-check chunk in-use bits after obtaining the lock to reuse a stale
-value, possibly from before the process became single-threaded. this
-in turn produced corruption of the heap state.
-
-some uses of libc.threads_minus_1 remain, especially for allocation of
-new TLS in the dynamic linker; otherwise, it could be removed
-entirely. it's made non-volatile to reflect that the remaining
-accesses are only made under lock on the thread list.
-
-instead of libc.threads_minus_1, libc.threaded is now used for
-skipping locks. the difference is that libc.threaded is permanently
-true once an additional thread has been created. this will produce
-some performance regression in processes that are mostly
-single-threaded but occasionally creating threads. in the future it
-may be possible to bring back the full lock-skipping, but more care
-needs to be taken to produce a safe design.
----
- src/internal/libc.h | 2 +-
- src/malloc/malloc.c | 2 +-
- src/thread/__lock.c | 2 +-
- 3 files changed, 3 insertions(+), 3 deletions(-)
-
-diff --git a/src/internal/libc.h b/src/internal/libc.h
-index ac97dc7e..c0614852 100644
---- a/src/internal/libc.h
-+++ b/src/internal/libc.h
-@@ -21,7 +21,7 @@ struct __libc {
- 	int can_do_threads;
- 	int threaded;
- 	int secure;
--	volatile int threads_minus_1;
-+	int threads_minus_1;
- 	size_t *auxv;
- 	struct tls_module *tls_head;
- 	size_t tls_size, tls_align, tls_cnt;
-diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
-index 96982596..2553a62e 100644
---- a/src/malloc/malloc.c
-+++ b/src/malloc/malloc.c
-@@ -26,7 +26,7 @@ int __malloc_replaced;
- 
- static inline void lock(volatile int *lk)
- {
--	if (libc.threads_minus_1)
-+	if (libc.threaded)
- 		while(a_swap(lk, 1)) __wait(lk, lk+1, 1, 1);
- }
- 
-diff --git a/src/thread/__lock.c b/src/thread/__lock.c
-index 45557c88..5b9b144e 100644
---- a/src/thread/__lock.c
-+++ b/src/thread/__lock.c
-@@ -18,7 +18,7 @@
- 
- void __lock(volatile int *l)
- {
--	if (!libc.threads_minus_1) return;
-+	if (!libc.threaded) return;
- 	/* fast path: INT_MIN for the lock, +1 for the congestion */
- 	int current = a_cas(l, 0, INT_MIN + 1);
- 	if (!current) return;
--- 
-2.21.0
-
-From f12888e9eb9eed60cc266b899dcafecb4752964a Mon Sep 17 00:00:00 2001
-From: Rich Felker <dalias@aerifal.cx>
-Date: Fri, 22 May 2020 17:25:38 -0400
-Subject: [PATCH 3/4] cut down size of some libc struct members
-
-these are all flags that can be single-byte values.
----
- src/internal/libc.h | 6 +++---
- 1 file changed, 3 insertions(+), 3 deletions(-)
-
-diff --git a/src/internal/libc.h b/src/internal/libc.h
-index c0614852..d47f58e0 100644
---- a/src/internal/libc.h
-+++ b/src/internal/libc.h
-@@ -18,9 +18,9 @@ struct tls_module {
- };
- 
- struct __libc {
--	int can_do_threads;
--	int threaded;
--	int secure;
-+	char can_do_threads;
-+	char threaded;
-+	char secure;
- 	int threads_minus_1;
- 	size_t *auxv;
- 	struct tls_module *tls_head;
--- 
-2.21.0
-
-From 8d81ba8c0bc6fe31136cb15c9c82ef4c24965040 Mon Sep 17 00:00:00 2001
-From: Rich Felker <dalias@aerifal.cx>
-Date: Fri, 22 May 2020 17:45:47 -0400
-Subject: [PATCH 4/4] restore lock-skipping for processes that return to
- single-threaded state
-
-the design used here relies on the barrier provided by the first lock
-operation after the process returns to single-threaded state to
-synchronize with actions by the last thread that exited. by storing
-the intent to change modes in the same object used to detect whether
-locking is needed, it's possible to avoid an extra (possibly costly)
-memory load after the lock is taken.
----
- src/internal/libc.h         | 1 +
- src/malloc/malloc.c         | 5 ++++-
- src/thread/__lock.c         | 4 +++-
- src/thread/pthread_create.c | 8 ++++----
- 4 files changed, 12 insertions(+), 6 deletions(-)
-
-diff --git a/src/internal/libc.h b/src/internal/libc.h
-index d47f58e0..619bba86 100644
---- a/src/internal/libc.h
-+++ b/src/internal/libc.h
-@@ -21,6 +21,7 @@ struct __libc {
- 	char can_do_threads;
- 	char threaded;
- 	char secure;
-+	volatile signed char need_locks;
- 	int threads_minus_1;
- 	size_t *auxv;
- 	struct tls_module *tls_head;
-diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
-index 2553a62e..a803d4c9 100644
---- a/src/malloc/malloc.c
-+++ b/src/malloc/malloc.c
-@@ -26,8 +26,11 @@ int __malloc_replaced;
- 
- static inline void lock(volatile int *lk)
- {
--	if (libc.threaded)
-+	int need_locks = libc.need_locks;
-+	if (need_locks) {
- 		while(a_swap(lk, 1)) __wait(lk, lk+1, 1, 1);
-+		if (need_locks < 0) libc.need_locks = 0;
-+	}
- }
- 
- static inline void unlock(volatile int *lk)
-diff --git a/src/thread/__lock.c b/src/thread/__lock.c
-index 5b9b144e..60eece49 100644
---- a/src/thread/__lock.c
-+++ b/src/thread/__lock.c
-@@ -18,9 +18,11 @@
- 
- void __lock(volatile int *l)
- {
--	if (!libc.threaded) return;
-+	int need_locks = libc.need_locks;
-+	if (!need_locks) return;
- 	/* fast path: INT_MIN for the lock, +1 for the congestion */
- 	int current = a_cas(l, 0, INT_MIN + 1);
-+	if (need_locks < 0) libc.need_locks = 0;
- 	if (!current) return;
- 	/* A first spin loop, for medium congestion. */
- 	for (unsigned i = 0; i < 10; ++i) {
-diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
-index 6a3b0c21..6bdfb44f 100644
---- a/src/thread/pthread_create.c
-+++ b/src/thread/pthread_create.c
-@@ -118,8 +118,8 @@ _Noreturn void __pthread_exit(void *result)
- 	 * until the lock is released, which only happens after SYS_exit
- 	 * has been called, via the exit futex address pointing at the lock.
- 	 * This needs to happen after any possible calls to LOCK() that might
--	 * skip locking if libc.threads_minus_1 is zero. */
--	libc.threads_minus_1--;
-+	 * skip locking if process appears single-threaded. */
-+	if (!--libc.threads_minus_1) libc.need_locks = -1;
- 	self->next->prev = self->prev;
- 	self->prev->next = self->next;
- 	self->prev = self->next = self;
-@@ -339,7 +339,7 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att
- 		~(1UL<<((SIGCANCEL-1)%(8*sizeof(long))));
- 
- 	__tl_lock();
--	libc.threads_minus_1++;
-+	if (!libc.threads_minus_1++) libc.need_locks = 1;
- 	ret = __clone((c11 ? start_c11 : start), stack, flags, args, &new->tid, TP_ADJ(new), &__thread_list_lock);
- 
- 	/* All clone failures translate to EAGAIN. If explicit scheduling
-@@ -363,7 +363,7 @@ int __pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict att
- 		new->next->prev = new;
- 		new->prev->next = new;
- 	} else {
--		libc.threads_minus_1--;
-+		if (!--libc.threads_minus_1) libc.need_locks = 0;
- 	}
- 	__tl_unlock();
- 	__restore_sigs(&set);
--- 
-2.21.0
-