[PATCH] madvise() does not always return -EBADF on non-file mapped area

The madvise() system call returns -EBADF for areas which does not map to files, only for *behaviour* request MADV_WILLNEED. According to man pages, madvise returns : EBADF - the map exists, but the area maps something that isn't a file. Fixes bug 2995. Signed-off-by: Suzuki K P <suzuki@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] madvise() does not always return -EBADF on non-file mapped area
The madvise() system call returns -EBADF for areas which does not map to files, only for *behaviour* request MADV_WILLNEED. According to man pages, madvise returns : EBADF - the map exists, but the area maps something that isn't a file. Fixes bug 2995. Signed-off-by: Suzuki K P <suzuki@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
suzuki · Linus Torvalds
1 parent 4bfdf37830
Showing 1 changed file with 8 additions and 5 deletions Side-by-side Diff
mm/madvise.c
@@ -83,9 +83,6 @@
 {
 	struct file *file = vma->vm_file;
  
-	if (!file)
-		return -EBADF;
-
 	if (file->f_mapping->a_ops->get_xip_page) {
 		/* no bad return value, but ignore advice */
 		return 0;
  
  
@@ -140,11 +137,16 @@
 	return 0;
 }
  
-static long madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
-			unsigned long start, unsigned long end, int behavior)
+static long
+madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
+		unsigned long start, unsigned long end, int behavior)
 {
+	struct file *filp = vma->vm_file;
 	long error = -EBADF;
  
+	if (!filp)
+		goto  out;
+
 	switch (behavior) {
 	case MADV_NORMAL:
 	case MADV_SEQUENTIAL:
@@ -165,6 +167,7 @@
 		break;
 	}
  
+out:
 	return error;
 }
...	...	@@ -83,9 +83,6 @@
83	83	{
84	84	struct file *file = vma->vm_file;
85	85
86		- if (!file)
87		- return -EBADF;
88		-
89	86	if (file->f_mapping->a_ops->get_xip_page) {
90	87	/* no bad return value, but ignore advice */
91	88	return 0;
92	89
93	90
...	...	@@ -140,11 +137,16 @@
140	137	return 0;
141	138	}
142	139
143		-static long madvise_vma(struct vm_area_struct vma, struct vm_area_struct *prev,
144		- unsigned long start, unsigned long end, int behavior)
	140	+static long
	141	+madvise_vma(struct vm_area_struct vma, struct vm_area_struct *prev,
	142	+ unsigned long start, unsigned long end, int behavior)
145	143	{
	144	+ struct file *filp = vma->vm_file;
146	145	long error = -EBADF;
147	146
	147	+ if (!filp)
	148	+ goto out;
	149	+
148	150	switch (behavior) {
149	151	case MADV_NORMAL:
150	152	case MADV_SEQUENTIAL:
...	...	@@ -165,6 +167,7 @@
165	167	break;
166	168	}
167	169
	170	+out:
168	171	return error;
169	172	}
170	173