[patch] 2.4.28 VMA Patch (Requires a.out patch)

2.4.28-vma.patch (text/plain), 7.95 KB, created by Tim Yamin (RETIRED) on 2004-12-24 16:25:32 UTC

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
#   2004/12/17 21:45:58-02:00 [e-mail] 
#   [PATCH] Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().  
#   
#   Backport of 2.6 fix to insert_vm_struct to make it return an error
#   rather than BUG().  This eliminates a user triggerable BUG() when user
#   created a large vma that overlapped with arg pages during exec (could be
#   triggered with a.out on i386 and x86_64 and elf on ia64).
#   
#   Signed-off-by: Chris Wright <[e-mail]>
#   
#   ===== arch/ia64/ia32/binfmt_elf32.c 1.13 vs edited =====
# 
# arch/ia64/ia32/binfmt_elf32.c
#   2004/12/17 17:22:06-02:00 [e-mail] +16 -4
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().
# 
# arch/ia64/mm/init.c
#   2004/12/17 15:25:47-02:00 [e-mail] +14 -2
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG(). 
# 
# arch/s390x/kernel/exec32.c
#   2004/12/17 15:32:42-02:00 [e-mail] +6 -2
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().  This eliminates a user triggerable BUG() when user
# 
# arch/x86_64/ia32/ia32_binfmt.c
#   2004/12/17 15:34:21-02:00 [e-mail] +6 -2
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().  This eliminates a user triggerable BUG() when user
# 
# fs/exec.c
#   2004/12/17 15:54:18-02:00 [e-mail] +6 -2
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().  
# 
# include/linux/mm.h
#   2004/12/16 20:38:37-02:00 [e-mail] +1 -1
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().  This eliminates a user triggerable BUG() when user
# 
# mm/mmap.c
#   2004/12/16 20:43:15-02:00 [e-mail] +3 -2
#   Backport of 2.6 fix to insert_vm_struct to make it return an error rather than BUG().
# 
diff -Nru a/arch/ia64/ia32/binfmt_elf32.c b/arch/ia64/ia32/binfmt_elf32.c
--- a/arch/ia64/ia32/binfmt_elf32.c	2004-12-19 07:39:49 -08:00
+++ b/arch/ia64/ia32/binfmt_elf32.c	2004-12-19 07:39:49 -08:00
@@ -95,7 +95,11 @@
 		vma->vm_private_data = NULL;
 		down_write(&current->mm->mmap_sem);
 		{
-			insert_vm_struct(current->mm, vma);
+			if (insert_vm_struct(current->mm, vma)) {
+				kmem_cache_free(vm_area_cachep, vma);
+				up_write(&current->mm->mmap_sem);
+				return;
+			}
 		}
 		up_write(&current->mm->mmap_sem);
 	}
@@ -117,7 +121,11 @@
 		vma->vm_private_data = NULL;
 		down_write(&current->mm->mmap_sem);
 		{
-			insert_vm_struct(current->mm, vma);
+			if (insert_vm_struct(current->mm, vma)) {
+				kmem_cache_free(vm_area_cachep, vma);
+				up_write(&current->mm->mmap_sem);
+				return;
+			}
 		}
 		up_write(&current->mm->mmap_sem);
 	}
@@ -164,7 +172,7 @@
 {
 	unsigned long stack_base;
 	struct vm_area_struct *mpnt;
-	int i;
+	int i, ret;
 
 	stack_base = IA32_STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE;
 
@@ -188,7 +196,11 @@
 		mpnt->vm_pgoff = 0;
 		mpnt->vm_file = NULL;
 		mpnt->vm_private_data = 0;
-		insert_vm_struct(current->mm, mpnt);
+		if ((ret = insert_vm_struct(current->mm, mpnt))) {
+			up_write(&current->mm->mmap_sem);
+			kmem_cache_free(vm_area_cachep, mpnt);
+			return ret;
+		}
 		current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
 	}
 
diff -Nru a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
--- a/arch/ia64/mm/init.c	2004-12-19 07:39:49 -08:00
+++ b/arch/ia64/mm/init.c	2004-12-19 07:39:49 -08:00
@@ -105,7 +105,13 @@
 		vma->vm_pgoff = 0;
 		vma->vm_file = NULL;
 		vma->vm_private_data = NULL;
-		insert_vm_struct(current->mm, vma);
+		down_write(&current->mm->mmap_sem);
+		if (insert_vm_struct(current->mm, vma)) {
+			up_write(&current->mm->mmap_sem);
+			kmem_cache_free(vm_area_cachep, vma);
+			return;
+		}
+		up_write(&current->mm->mmap_sem);
 	}
 
 	/* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
@@ -117,7 +123,13 @@
 			vma->vm_end = PAGE_SIZE;
 			vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
 			vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | VM_RESERVED;
-			insert_vm_struct(current->mm, vma);
+			down_write(&current->mm->mmap_sem);
+			if (insert_vm_struct(current->mm, vma)) {
+				up_write(&current->mm->mmap_sem);
+				kmem_cache_free(vm_area_cachep, vma);
+				return;
+			}
+			up_write(&current->mm->mmap_sem);
 		}
 	}
 }
diff -Nru a/arch/s390x/kernel/exec32.c b/arch/s390x/kernel/exec32.c
--- a/arch/s390x/kernel/exec32.c	2004-12-19 07:39:49 -08:00
+++ b/arch/s390x/kernel/exec32.c	2004-12-19 07:39:49 -08:00
@@ -41,7 +41,7 @@
 {
 	unsigned long stack_base;
 	struct vm_area_struct *mpnt;
-	int i;
+	int i, ret;
 
 	stack_base = STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE;
 
@@ -65,7 +65,11 @@
 		mpnt->vm_pgoff = 0;
 		mpnt->vm_file = NULL;
 		mpnt->vm_private_data = (void *) 0;
-		insert_vm_struct(current->mm, mpnt);
+		if ((ret = insert_vm_struct(current->mm, mpnt))) {
+			up_write(&current->mm->mmap_sem);
+			kmem_cache_free(vm_area_cachep, mpnt);
+			return ret;
+		}
 		current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
 	} 
 
diff -Nru a/arch/x86_64/ia32/ia32_binfmt.c b/arch/x86_64/ia32/ia32_binfmt.c
--- a/arch/x86_64/ia32/ia32_binfmt.c	2004-12-19 07:39:49 -08:00
+++ b/arch/x86_64/ia32/ia32_binfmt.c	2004-12-19 07:39:49 -08:00
@@ -225,7 +225,7 @@
 {
 	unsigned long stack_base;
 	struct vm_area_struct *mpnt;
-	int i;
+	int i, ret;
 
 	stack_base = IA32_STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE;
 
@@ -250,7 +250,11 @@
 		mpnt->vm_pgoff = 0;
 		mpnt->vm_file = NULL;
 		mpnt->vm_private_data = (void *) 0;
-		insert_vm_struct(current->mm, mpnt);
+		if ((ret = insert_vm_struct(current->mm, mpnt))) {
+			up_write(&current->mm->mmap_sem);
+			kmem_cache_free(vm_area_cachep, mpnt);
+			return ret;
+		}
 		current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
 	} 
 
diff -Nru a/fs/exec.c b/fs/exec.c
--- a/fs/exec.c	2004-12-19 07:39:49 -08:00
+++ b/fs/exec.c	2004-12-19 07:39:49 -08:00
@@ -327,7 +327,7 @@
 {
 	unsigned long stack_base;
 	struct vm_area_struct *mpnt;
-	int i;
+	int i, ret;
 
 	stack_base = STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE;
 
@@ -387,7 +387,6 @@
 
 	down_write(&current->mm->mmap_sem);
 	{
-		struct vm_area_struct *vma;
 		mpnt->vm_mm = current->mm;
 		mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
 		mpnt->vm_end = STACK_TOP;
@@ -402,13 +401,11 @@
 		mpnt->vm_pgoff = 0;
 		mpnt->vm_file = NULL;
 		mpnt->vm_private_data = (void *) 0;
-		vma = find_vma(current->mm, mpnt->vm_start);
-		if (vma) {
+		if ((ret = insert_vm_struct(current->mm, mpnt))) {
 			up_write(&current->mm->mmap_sem);
 			kmem_cache_free(vm_area_cachep, mpnt);
-			return -ENOMEM;
+			return ret;
 		}
-		insert_vm_struct(current->mm, mpnt);
 		current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
 	} 
 
diff -Nru a/include/linux/mm.h b/include/linux/mm.h
--- a/include/linux/mm.h	2004-12-19 07:39:49 -08:00
+++ b/include/linux/mm.h	2004-12-19 07:39:49 -08:00
@@ -548,7 +548,7 @@
 /* mmap.c */
 extern void lock_vma_mappings(struct vm_area_struct *);
 extern void unlock_vma_mappings(struct vm_area_struct *);
-extern void insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
+extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
 extern void __insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
 extern void build_mmap_rb(struct mm_struct *);
 extern void exit_mmap(struct mm_struct *);
diff -Nru a/mm/mmap.c b/mm/mmap.c
--- a/mm/mmap.c	2004-12-19 07:39:49 -08:00
+++ b/mm/mmap.c	2004-12-19 07:39:49 -08:00
@@ -1193,14 +1193,15 @@
 	validate_mm(mm);
 }
 
-void insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
+int insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
 {
 	struct vm_area_struct * __vma, * prev;
 	rb_node_t ** rb_link, * rb_parent;
 
 	__vma = find_vma_prepare(mm, vma->vm_start, &prev, &rb_link, &rb_parent);
 	if (__vma && __vma->vm_start < vma->vm_end)
-		BUG();
+		return -ENOMEM;
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 	validate_mm(mm);
+	return 0;
 }