[PATCH] fuse: fix error case in fuse_readpages

Don't let fuse_readpages leave the @pages list not empty when exiting on error. [akpm@osdl.org: kernel-doc fixes] Signed-off-by: Alexander Zarochentsev <zam@namesys.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] fuse: fix error case in fuse_readpages
Don't let fuse_readpages leave the @pages list not empty when exiting on error. [akpm@osdl.org: kernel-doc fixes] Signed-off-by: Alexander Zarochentsev <zam@namesys.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alexander Zarochentsev · Greg Kroah-Hartman
1 parent 9b41ea7289
Showing 3 changed files with 29 additions and 2 deletions Side-by-side Diff
fs/fuse/file.c
include/linux/mm.h
mm/swap.c
@@ -395,14 +395,16 @@
 	struct fuse_readpages_data data;
 	int err;
  
+	err = -EIO;
 	if (is_bad_inode(inode))
-		return -EIO;
+		goto clean_pages_up;
  
 	data.file = file;
 	data.inode = inode;
 	data.req = fuse_get_req(fc);
+	err = PTR_ERR(data.req);
 	if (IS_ERR(data.req))
-		return PTR_ERR(data.req);
+		goto clean_pages_up;
  
 	err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
 	if (!err) {
@@ -411,6 +413,10 @@
 		else
 			fuse_put_request(fc, data.req);
 	}
+	return err;
+
+clean_pages_up:
+	put_pages_list(pages);
 	return err;
 }
  
@@ -336,6 +336,7 @@
 }
  
 void put_page(struct page *page);
+void put_pages_list(struct list_head *pages);
  
 void split_page(struct page *page, unsigned int order);
  
@@ -54,6 +54,26 @@
 }
 EXPORT_SYMBOL(put_page);
  
+/**
+ * put_pages_list(): release a list of pages
+ *
+ * Release a list of pages which are strung together on page.lru.  Currently
+ * used by read_cache_pages() and related error recovery code.
+ *
+ * @pages: list of pages threaded on page->lru
+ */
+void put_pages_list(struct list_head *pages)
+{
+	while (!list_empty(pages)) {
+		struct page *victim;
+
+		victim = list_entry(pages->prev, struct page, lru);
+		list_del(&victim->lru);
+		page_cache_release(victim);
+	}
+}
+EXPORT_SYMBOL(put_pages_list);
+
 /*
  * Writeback is about to end against a page which has been marked for immediate
  * reclaim.  If it still appears to be reclaimable, move it to the tail of the
...	...	@@ -395,14 +395,16 @@
395	395	struct fuse_readpages_data data;
396	396	int err;
397	397
	398	+ err = -EIO;
398	399	if (is_bad_inode(inode))
399		- return -EIO;
	400	+ goto clean_pages_up;
400	401
401	402	data.file = file;
402	403	data.inode = inode;
403	404	data.req = fuse_get_req(fc);
	405	+ err = PTR_ERR(data.req);
404	406	if (IS_ERR(data.req))
405		- return PTR_ERR(data.req);
	407	+ goto clean_pages_up;
406	408
407	409	err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
408	410	if (!err) {
...	...	@@ -411,6 +413,10 @@
411	413	else
412	414	fuse_put_request(fc, data.req);
413	415	}
	416	+ return err;
	417	+
	418	+clean_pages_up:
	419	+ put_pages_list(pages);
414	420	return err;
415	421	}
416	422
...	...	@@ -336,6 +336,7 @@
336	336	}
337	337
338	338	void put_page(struct page *page);
	339	+void put_pages_list(struct list_head *pages);
339	340
340	341	void split_page(struct page *page, unsigned int order);
341	342
...	...	@@ -54,6 +54,26 @@
54	54	}
55	55	EXPORT_SYMBOL(put_page);
56	56
	57	+/**
	58	+ * put_pages_list(): release a list of pages
	59	+ *
	60	+ * Release a list of pages which are strung together on page.lru. Currently
	61	+ * used by read_cache_pages() and related error recovery code.
	62	+ *
	63	+ * @pages: list of pages threaded on page->lru
	64	+ */
	65	+void put_pages_list(struct list_head *pages)
	66	+{
	67	+ while (!list_empty(pages)) {
	68	+ struct page *victim;
	69	+
	70	+ victim = list_entry(pages->prev, struct page, lru);
	71	+ list_del(&victim->lru);
	72	+ page_cache_release(victim);
	73	+ }
	74	+}
	75	+EXPORT_SYMBOL(put_pages_list);
	76	+
57	77	/*
58	78	* Writeback is about to end against a page which has been marked for immediate
59	79	* reclaim. If it still appears to be reclaimable, move it to the tail of the