experiment

gpkg/glibc/build.sh

@@ -16,7 +16,7 @@ termux_step_pre_configure() {
 		termux_error_exit "Compilation is only possible based on glibc"
 	fi
 
-	for i in shmem-android.h ignore-syscall.h mprotect.c; do
+	for i in shmem-android.h ignore-syscall.h; do
 		install -Dm644 "${TERMUX_PKG_BUILDER_DIR}/${i}" "${TERMUX_PKG_SRCDIR}/sysdeps/unix/sysv/linux/${i}"
 	done
 

gpkg/glibc/dl-load.c.patch

@@ -0,0 +1,13 @@
+--- src/elf/dl-load.c	2023-07-31 20:54:16.000000000 +0300
++++ src/elf/dl-load.c.patch	2023-12-24 17:48:46.238884735 +0300
+@@ -90,9 +90,7 @@
+
+
+ int __stack_prot attribute_hidden attribute_relro
+-#if _STACK_GROWS_DOWN && defined PROT_GROWSDOWN
+-  = PROT_GROWSDOWN;
+-#elif _STACK_GROWS_UP && defined PROT_GROWSUP
++#if _STACK_GROWS_UP && defined PROT_GROWSUP
+   = PROT_GROWSUP;
+ #else
+   = 0;

gpkg/glibc/mprotect.c

@@ -82,15 +82,12 @@ int __mprotect(void *addr, size_t len, int prot) {
 	if (res == -1 && errno == EACCES && prot & PROT_EXEC && !__is_mmaped(addr)) {
 		size_t saddr = strlen(addr)+1;
 		void *caddr;
-		int mmap_flags = MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED;
-		if (prot & PROT_GROWSDOWN)
-			mmap_flags |= MAP_GROWSDOWN;
 		if (saddr > 1) {
 			caddr = malloc(saddr);
 			memcpy(caddr, addr, saddr);
 		}
 		free(addr);
-		addr = mmap(addr, len, PROT_READ|PROT_WRITE|PROT_EXEC, mmap_flags, -1, 0);
+		addr = mmap(addr, len, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED, -1, 0);
 		if (saddr > 1)
 			memcpy(addr, caddr, saddr);
 		return INLINE_SYSCALL_CALL(mprotect, addr, len, prot);

gpkg/glibc/rtld.c.patch

@@ -0,0 +1,11 @@
+--- src/elf/rtld.c	2023-12-13 09:28:35.942403098 +0300
++++ src/elf/rtld.c.patch	2023-12-24 17:46:54.788884778 +0300
+@@ -486,7 +486,7 @@
+ #endif
+
+   /* Initialize the stack end variable.  */
+-  __libc_stack_end = __builtin_frame_address (0);
++  __libc_stack_end = mmap(NULL, GLRO(dl_pagesize), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+
+   /* Call the OS-dependent function to set up life so we can do things like
+      file access.  It will call `dl_main' (below) to do all the real work