Change the way text_addr and data_addr are computed to use the

executable status of segments instead of detecting the main text segment
by which segment contains the program entry point. This affects
obreak() and is required for correct operation of that function
on 64-bit PowerPC systems. The previous behavior was apparently
required only for the Alpha, which is no longer supported.

Reviewed by:	jhb
Tested on:	amd64, sparc64, powerpc

1 files changed, 6 insertions, 11 deletions

diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 0fffb9f..47e1f64 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -832,13 +832,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 			    phdr[i].p_vaddr + et_dyn_addr - seg_addr);
 
 			/*
-			 * Is this .text or .data?  We can't use
-			 * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the
-			 * alpha terribly and possibly does other bad
-			 * things so we stick to the old way of figuring
-			 * it out:  If the segment contains the program
-			 * entry point, it's a text segment, otherwise it
-			 * is a data segment.
+			 * Make the largest executable segment the official
+			 * text segment and all others data.
 			 *
 			 * Note that obreak() assumes that data_addr + 
 			 * data_size == end of data load area, and the ELF
@@ -846,12 +841,10 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 			 * address.  If multiple data segments exist, the
 			 * last one will be used.
 			 */
-			if (hdr->e_entry >= phdr[i].p_vaddr &&
-			    hdr->e_entry < (phdr[i].p_vaddr +
-			    phdr[i].p_memsz)) {
+
+			if (phdr[i].p_flags & PF_X && text_size < seg_size) {
 				text_size = seg_size;
 				text_addr = seg_addr;
-				entry = (u_long)hdr->e_entry + et_dyn_addr;
 			} else {
 				data_size = seg_size;
 				data_addr = seg_addr;
@@ -871,6 +864,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 		data_size = text_size;
 	}
 
+	entry = (u_long)hdr->e_entry + et_dyn_addr;
+
 	/*
 	 * Check limits.  It should be safe to check the
 	 * limits after loading the segments since we do