msync() and UMF_LINUX fiddling

modified:   p_lx_elf.cpp
	modified:   stub/src/amd64-linux.elf-entry.S
	modified:   stub/src/amd64-linux.elf-so_fold.S
	modified:   stub/src/arm.v4a-linux.elf-entry.S
	modified:   stub/src/arm.v4a-linux.elf-entry.lds
	modified:   stub/src/arm.v4a-linux.elf-fold.S
	modified:   stub/src/arm.v4a-linux.elf-so_entry.S
	modified:   stub/src/arm64-linux.elf-so_fold.S
	modified:   stub/src/mips.r3000-linux.elf-entry.lds
	modified:   stub/src/mipsel.r3000-linux.elf-entry.S
	modified:   stub/src/mipsel.r3000-linux.elf-entry.lds
	modified:   stub/src/mipsel.r3000-linux.elf-fold.S
	modified:   stub/src/upxfd_linux.c

src/p_lx_elf.cpp

@@ -1487,14 +1487,10 @@ PackLinuxElf32::buildLinuxLoader(
         len += snprintf(&sec[len], sizeof(sec) - len, ",%s", "EXP_TAIL");
         // End of daisy-chain fall-through.
 
-        if (this->e_machine==Elf32_Ehdr::EM_386
+        len += snprintf(&sec[len], sizeof(sec) - len, ",%s",
-        ||  this->e_machine==Elf32_Ehdr::EM_ARM) {
+            (sec_arm_attr || is_asl || opt->o_unix.android_shlib)
-            len += snprintf(&sec[len], sizeof(sec) - len, ",%s",
+                ? "UMF_ANDROID"
-                (opt->o_unix.android_old ? "UMF_ANDROID" : "UMF_LINUX"));
+                : "UMF_LINUX");
-        }
-        else {
-            len += snprintf(&sec[len], sizeof(sec) - len, ",%s", "UMF_LINUX");
-        }
         if (hasLoaderSection("STRCON")) {
             len += snprintf(&sec[len], sizeof(sec) - len, ",%s", "STRCON");
         }
@@ -1536,14 +1532,10 @@ PackLinuxElf32::buildLinuxLoader(
                 "LZMA_DAISY,LZMA_ELF00,LZMA_DEC20,LZMA_DEC30");
         }
         len += snprintf(&sec[len], sizeof(sec) - len, ",%s", "EXP_TAIL");
-        if (this->e_machine==Elf32_Ehdr::EM_386
+        len += snprintf(&sec[len], sizeof(sec) - len, ",%s",
-        ||  this->e_machine==Elf32_Ehdr::EM_ARM) {
+            (sec_arm_attr || is_asl || opt->o_unix.android_shlib)
-            len += snprintf(&sec[len], sizeof(sec) - len, ",%s",
+                ? "UMF_ANDROID"
-                (opt->o_unix.android_old ? "UMF_ANDROID" : "UMF_LINUX"));
+                : "UMF_LINUX");
-        }
-        else {
-            len += snprintf(&sec[len], sizeof(sec) - len, ",%s", "UMF_LINUX");
-        }
         if (hasLoaderSection("SYSCALLS")) {
             len += snprintf(&sec[len], sizeof(sec) - len, ",%s", "SYSCALLS");
         }
@@ -1605,13 +1597,9 @@ PackLinuxElf32::buildLinuxLoader(
           )
     ) { // shlib with ELF2 de-compressor
         addLoader("ELFMAINX");
-        if (this->e_machine==Elf32_Ehdr::EM_386
+        addLoader((sec_arm_attr || is_asl || opt->o_unix.android_shlib)
-        ||  this->e_machine==Elf32_Ehdr::EM_ARM) {
+            ? "UMF_ANDROID"
-            addLoader((opt->o_unix.android_old ? "UMF_ANDROID" : "UMF_LINUX"));
+            : "UMF_LINUX");
-        }
-        else {
-            addLoader("UMF_LINUX");
-        }
         addLoader("ELFMAINZ,FOLDEXEC,IDENTSTR");
     }
     else if (this->e_machine==Elf32_Ehdr::EM_NONE
@@ -1621,10 +1609,9 @@ PackLinuxElf32::buildLinuxLoader(
           || this->e_machine==Elf32_Ehdr::EM_MIPS
       ) { // main program with ELF2 de-compressor
         addLoader("ELFMAINX");
-        if (this->e_machine==Elf32_Ehdr::EM_386
+        addLoader((sec_arm_attr || is_asl || opt->o_unix.android_shlib)
-        ||  this->e_machine==Elf32_Ehdr::EM_ARM) {
+            ? "UMF_ANDROID"
-            addLoader((opt->o_unix.android_old ? "UMF_ANDROID" : "UMF_LINUX"));
+            : "UMF_LINUX");
-        }
         addLoader("ELFMAINZ,FOLDEXEC,IDENTSTR");
             defineSymbols(ft);
     }

src/stub/src/amd64-linux.elf-entry.S

@@ -42,6 +42,7 @@ __NR_ftruncate= 77
 __NR_exit=     60
 __NR_mprotect= 10
 __NR_mmap=      9
+__NR_msync=    26  // 0x1a
 __NR_close=     3
 __NR_open=      2
 __NR_write=     1

src/stub/src/amd64-linux.elf-so_fold.S

@@ -103,6 +103,7 @@ __NR_close= 3
 
 __NR_mmap=      9
 __NR_mprotect= 10
+__NR_msync=    26  // 0x1a
 __NR_munmap=   11
 __NR_mremap=  216
 __NR_memfd_create= 0x13f  // 319
@@ -169,6 +170,8 @@ ftruncate: .globl ftruncate
         push $__NR_ftruncate; 5: jmp 5f
 memfd_create: .globl memfd_create
         push $__NR_memfd_create; 5: jmp 5f
+msync: .globl msync
+        push $__NR_msync; 5: jmp 5f
 close: .globl close
         push $ __NR_close; 5: jmp 5f
 openat: .globl openat

src/stub/src/arm.v4a-linux.elf-entry.S

@@ -93,6 +93,7 @@ __NR_memfd_create= 385 + __NR_SYSCALL_BASE
 __NR_mkdir=    39 + __NR_SYSCALL_BASE
 __NR_mmap2=   192 + __NR_SYSCALL_BASE
 __NR_mprotect=125 + __NR_SYSCALL_BASE
+__NR_msync=   144 + __NR_SYSCALL_BASE  // 0x90
 __NR_open=      5 + __NR_SYSCALL_BASE
 __NR_read=      3 + __NR_SYSCALL_BASE
 __NR_stat=    106 + __NR_SYSCALL_BASE
@@ -377,6 +378,7 @@ mempcpy: .globl mempcpy  // (dst, src, n)
 .globl getpid;    getpid:    do_sys __NR_getpid; ret
 .globl lseek;     lseek:     do_sys __NR_lseek; ret
 .globl mkdir;     mkdir:     do_sys __NR_mkdir; ret
+.globl msync;     msync:     do_sys __NR_msync; ret
 .globl open;      open:      do_sys __NR_open; ret
 .globl read;      read:      do_sys __NR_read; ret
 .globl stat;      stat:      do_sys __NR_stat; ret

src/stub/src/arm.v4a-linux.elf-entry.lds

@@ -9,4 +9,7 @@ SECTIONS
     *(ELFMAINX)
     *(.text)
   }
+  ELFMAINZ : {
+    *(ELFMAINZ)
+  }
 }

src/stub/src/arm.v4a-linux.elf-fold.S

@@ -472,6 +472,7 @@ getpid:.globl getpid;do_sys __NR_getpid; ret
 lseek: .globl lseek; do_sys __NR_lseek; ret
 memfd_create: .globl memfd_create; do_sys2 __NR_memfd_create; ret
 mkdir: .globl mkdir; do_sys __NR_mkdir; ret
+msync: .globl msync; do_sys __NR_msync; ret
 munmap: .globl munmap; do_sys __NR_munmap; ret  // BEWARE: get_sys_munmap knows where 'svc' lives!
 open:  .globl open;  do_sys __NR_open; ret
 read:  .globl read;  do_sys __NR_read; ret

src/stub/src/arm.v4a-linux.elf-so_entry.S

@@ -246,6 +246,7 @@ f_decompress:
 //  MATCH_07  envp
 
 upx_mmap_and_fd: .globl upx_mmap_and_fd
+        // UMF_LINX or UMF_ANDROID goes here
 
 // IDENTSTR goes here
 

src/stub/src/arm64-linux.elf-so_fold.S

@@ -103,6 +103,7 @@ __NR_unlinkat = 0x23 + __NR_SYSCALL_BASE  // 35
 
 __NR_mmap     = 0xde + __NR_SYSCALL_BASE  // 222
 __NR_mprotect = 0xe2 + __NR_SYSCALL_BASE  // 226
+__NR_msync    = 0xe3 + __NR_SYSCALL_BASE  // 227
 __NR_munmap   = 0xd7 + __NR_SYSCALL_BASE  // 215
 __NR_memfd_create = 0x117 + __NR_SYSCALL_BASE  // 279
 __NR_ftruncate= 0x2e + __NR_SYSCALL_BASE  // 46
@@ -154,6 +155,9 @@ Punmap: .globl Punmap
 munmap: .globl munmap
         do_sys __NR_munmap; ret
 
+msync: .globl msync
+        do_sys __NR_msync; ret
+
 // Sometimes Linux enforces page-aligned address
 Pprotect: .globl Pprotect
 mprotect: .globl mprotect

src/stub/src/mips.r3000-linux.elf-entry.lds

@@ -9,4 +9,7 @@ SECTIONS
     *(ELFMAINX)
     *(.text)
   }
+  ELFMAINZ : {
+    *(ELFMAINZ)
+  }
 }

src/stub/src/mipsel.r3000-linux.elf-entry.S

@@ -114,9 +114,11 @@ M_NRV2E_LE32=8
 __NR_Linux = 4000
 __NR_close    =   6+ __NR_Linux
 __NR_exit     =   1+ __NR_Linux
-__NR_memfd_create= 354 + __NR_Linux
+__NR_ftruncate=  93+ __NR_Linux
+__NR_memfd_create= 354+ __NR_Linux
 __NR_mmap     =  90+ __NR_Linux
 __NR_mprotect = 125+ __NR_Linux
+__NR_msync    = 144+ __NR_LINUX
 __NR_open     =   5+ __NR_Linux
 __NR_write    =   4+ __NR_Linux
 __NR_cacheflush = 147+ __NR_Linux
@@ -185,10 +187,9 @@ eof_n2b:
           addiu sp,4
 
         .balign 4
-upx_mmap_and_fd:
+upx_mmap_and_fd: .globl upx_mmap_and_fd
-// section UMF_LINUX or UMF_ANDROID goes here
+        // section UMF_LINUX or UMF_ANDROID goes here
 
-  section ELFMAINZ
   section ELFMAINZ; .set noreorder
 L72:
         li a0,2  # fd stderr
@@ -261,6 +262,16 @@ unfold:  # IN: $r_fexp,$r_auxv,$r_PMASK,$r_FOLD
         jr ra
           addu $r_ADRX,$r_elfa,$r_ADRX  # compressed data
 
+memfd_create: .globl memfd_create
+        li v0,__NR_memfd_create; syscall
+        j ra
+          nop
+
+ftruncate: .globl ftruncate
+        li v0,__NR_ftruncate; syscall
+        j ra
+          nop
+
 zfind:  # result in $r_auxv
         lw v1,(a0); addiu a0,a0,NBPW
         bnez v1,zfind

src/stub/src/mipsel.r3000-linux.elf-entry.lds

@@ -9,4 +9,7 @@ SECTIONS
     *(ELFMAINX)
     *(.text)
   }
+  ELFMAINZ : {
+    *(ELFMAINZ)
+  }
 }

src/stub/src/mipsel.r3000-linux.elf-fold.S

@@ -391,7 +391,8 @@ mmap: .globl mmap
         b sysret
           addiu sp,sp,sp_frame
 
-sysgo:
+sysgo:  // src/mipsel.r3000-linux.elf-fold.S
+sysgo2:
         syscall
 sysret:
         bgez a3,sysOK

src/stub/src/upxfd_linux.c

@@ -30,7 +30,7 @@ extern void my_bkpt(void const *, ...);
 #define ANDROID_FRIEND 0
 #define addr_string(string) ({ \
     char const *str; \
-    asm("bal 0f; .asciz \"" string "\"; .balign 4\n0: move %0,$31" \
+    asm(".set noreorder; bal 0f; .asciz \"" string "\"; .balign 4\n0: move %0,$31; .set reorder" \
 /*out*/ : "=r"(str) \
 /* in*/ : \
 /*und*/ : "ra"); \