Issue18826 fix (#35137)

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Fixes mono/mono#18826

Co-authored-by: HinTak <HinTak@users.noreply.github.com>

diff --git a/src/mono/mono/mini/main.c b/src/mono/mono/mini/main.c
index b857ec3..7cc3fec 100644 (file)
--- a/src/mono/mono/mini/main.c
+++ b/src/mono/mono/mini/main.c
@@ -35,6 +35,9 @@
 #    include "buildver-boehm.h"
 #  endif
 #endif
+#ifdef TARGET_OSX
+#include <mach-o/loader.h>
+#endif
 
 //#define TEST_ICALL_SYMBOL_MAP 1
 
@@ -179,8 +182,68 @@ probe_embedded (const char *program, int *ref_argc, char **ref_argv [])
                goto doclose;
        if (read (fd, sigbuffer, sizeof (sigbuffer)) == -1)
                goto doclose;
-       if (memcmp (sigbuffer+sizeof(uint64_t), "xmonkeysloveplay", 16) != 0)
-               goto doclose;
+       // First, see if "xmonkeysloveplay" is at the end of file
+       if (memcmp (sigbuffer + sizeof (uint64_t), "xmonkeysloveplay", 16) == 0)
+               goto found;
+
+#ifdef TARGET_OSX
+       {
+               /*
+                * If "xmonkeysloveplay" is not at the end of file,
+                * on Mac OS X, we try a little harder, by actually
+                * reading the binary's header structure, to see
+                * if it is located at the end of a LC_SYMTAB section.
+                *
+                * This is because Apple code-signing appends a
+                * LC_CODE_SIGNATURE section to the binary, so
+                * for a signed binary, "xmonkeysloveplay" is no
+                * longer at the end of file.
+                *
+                * The rest is sanity-checks for the header and section structures.
+                */
+               struct mach_header_64 bin_header;
+               if ((sigstart = lseek (fd, 0, SEEK_SET)) == -1)
+                       goto doclose;
+               // Find and check binary header
+               if (read (fd, &bin_header, sizeof (bin_header)) == -1)
+                       goto doclose;
+               if (bin_header.magic != MH_MAGIC_64)
+                       goto doclose;
+
+               off_t total = bin_header.sizeofcmds;
+               uint32_t count = bin_header.ncmds;
+               while (total > 0 && count > 0) {
+                       struct load_command lc;
+                       off_t sig_stored = lseek (fd, 0, SEEK_CUR); // get current offset
+                       if (read (fd, &lc, sizeof (lc)) == -1)
+                               goto doclose;
+                       if (lc.cmd == LC_SYMTAB) {
+                               struct symtab_command stc;
+                               if ((sigstart = lseek (fd, -sizeof (lc), SEEK_CUR)) == -1)
+                                       goto doclose;
+                               if (read (fd, &stc, sizeof (stc)) == -1)
+                                       goto doclose;
+
+                               // Check the end of the LC_SYMTAB section for "xmonkeysloveplay"
+                               if ((sigstart = lseek (fd, -(16 + sizeof (uint64_t)) + stc.stroff + stc.strsize, SEEK_SET)) == -1)
+                                       goto doclose;
+                               if (read (fd, sigbuffer, sizeof (sigbuffer)) == -1)
+                                       goto doclose;
+                               if (memcmp (sigbuffer + sizeof (uint64_t), "xmonkeysloveplay", 16) == 0)
+                                       goto found;
+                       }
+                       if ((sigstart = lseek (fd, sig_stored + lc.cmdsize, SEEK_SET)) == -1)
+                               goto doclose;
+                       total -= sizeof (lc.cmdsize);
+                       count--;
+               }
+       }
+#endif
+
+       // did not find "xmonkeysloveplay" at end of file or end of LC_SYMTAB section
+       goto doclose;
+
+found:
        directory_location = GUINT64_FROM_LE ((*(uint64_t *) &sigbuffer [0]));
        if (lseek (fd, directory_location, SEEK_SET) == -1)
                goto doclose;