patch-2.4.17 linux/fs/binfmt_elf.c

• Lines: 123
• Date: Fri Dec 21 16:40:32 2001
• Orig file: linux-2.4.16/fs/binfmt_elf.c
• Orig date: Sun Oct 21 02:16:59 2001

diff -Naur -X /home/marcelo/lib/dontdiff linux-2.4.16/fs/binfmt_elf.c linux/fs/binfmt_elf.c
@@ -32,7 +32,7 @@
 #include <linux/highuid.h>
 #include <linux/smp_lock.h>
 #include <linux/compiler.h>
-#include <linux/limits.h>
+#include <linux/highmem.h>
 
 #include <asm/uaccess.h>
 #include <asm/param.h>
@@ -1032,6 +1032,25 @@
 	elf_fpregset_t fpu;		/* NT_PRFPREG */
 	struct elf_prpsinfo psinfo;	/* NT_PRPSINFO */
 
+	/* first copy the parameters from user space */
+	memset(&psinfo, 0, sizeof(psinfo));
+	{
+		int i, len;
+
+		len = current->mm->arg_end - current->mm->arg_start;
+		if (len >= ELF_PRARGSZ)
+			len = ELF_PRARGSZ-1;
+		copy_from_user(&psinfo.pr_psargs,
+			      (const char *)current->mm->arg_start, len);
+		for(i = 0; i < len; i++)
+			if (psinfo.pr_psargs[i] == 0)
+				psinfo.pr_psargs[i] = ' ';
+		psinfo.pr_psargs[len] = 0;
+
+	}
+
+	/* now stop all vm operations */
+	down_write(&current->mm->mmap_sem);
 	segs = current->mm->map_count;
 
 #ifdef DEBUG
@@ -1073,7 +1092,6 @@
 	 * Set up the notes in similar form to SVR4 core dumps made
 	 * with info from their /proc.
 	 */
-	memset(&psinfo, 0, sizeof(psinfo));
 	memset(&prstatus, 0, sizeof(prstatus));
 
 	notes[0].name = "CORE";
@@ -1129,23 +1147,6 @@
 	psinfo.pr_flag = current->flags;
 	psinfo.pr_uid = NEW_TO_OLD_UID(current->uid);
 	psinfo.pr_gid = NEW_TO_OLD_GID(current->gid);
-	{
-		int i, len;
-
-		set_fs(fs);
-
-		len = current->mm->arg_end - current->mm->arg_start;
-		if (len >= ELF_PRARGSZ)
-			len = ELF_PRARGSZ-1;
-		copy_from_user(&psinfo.pr_psargs,
-			      (const char *)current->mm->arg_start, len);
-		for(i = 0; i < len; i++)
-			if (psinfo.pr_psargs[i] == 0)
-				psinfo.pr_psargs[i] = ' ';
-		psinfo.pr_psargs[len] = 0;
-
-		set_fs(KERNEL_DS);
-	}
 	strncpy(psinfo.pr_fname, current->comm, sizeof(psinfo.pr_fname));
 
 	notes[2].name = "CORE";
@@ -1217,8 +1218,6 @@
 		if (!writenote(&notes[i], file))
 			goto end_coredump;
 
-	set_fs(fs);
-
 	DUMP_SEEK(dataoff);
 
 	for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
@@ -1232,22 +1231,24 @@
 		for (addr = vma->vm_start;
 		     addr < vma->vm_end;
 		     addr += PAGE_SIZE) {
-			pgd_t *pgd;
-			pmd_t *pmd;
-			pte_t *pte;
-
-			pgd = pgd_offset(vma->vm_mm, addr);
-			if (pgd_none(*pgd))
-				goto nextpage_coredump;
-			pmd = pmd_offset(pgd, addr);
-			if (pmd_none(*pmd))
-				goto nextpage_coredump;
-			pte = pte_offset(pmd, addr);
-			if (pte_none(*pte)) {
-nextpage_coredump:
+			struct page* page;
+			struct vm_area_struct *vma;
+
+			if (get_user_pages(current, current->mm, addr, 1, 0, 1,
+						&page, &vma) <= 0) {
 				DUMP_SEEK (file->f_pos + PAGE_SIZE);
 			} else {
-				DUMP_WRITE((void*)addr, PAGE_SIZE);
+				if (page == ZERO_PAGE(addr)) {
+					DUMP_SEEK (file->f_pos + PAGE_SIZE);
+				} else {
+					void *kaddr;
+					flush_cache_page(vma, addr);
+					kaddr = kmap(page);
+					DUMP_WRITE(kaddr, PAGE_SIZE);
+					flush_page_to_ram(page);
+					kunmap(page);
+				}
+				put_page(page);
 			}
 		}
 	}
@@ -1260,6 +1261,7 @@
 
  end_coredump:
 	set_fs(fs);
+	up_write(&current->mm->mmap_sem);
 	return has_dumped;
 }
 #endif		/* USE_ELF_CORE_DUMP */