diff options
authorJaegeuk Kim <jaegeuk.kim@samsung.com>2014-04-18 15:21:04 +0900
committerJaegeuk Kim <jaegeuk.kim@samsung.com>2014-05-07 10:21:55 +0900
commite8271fa3908de52937d298b339f9f7984c491cc6 (patch)
parent7ee0eeabcdbb1610d7bc75d1132a43e0c7f7ef28 (diff)
f2fs: avoid BUG_ON when mouting corrupted image having garbage blocks
If the disk has some garbage blocks, F2FS is able to face with BUG_ON when recovering direct node blocks. This patch detects the error case and avoids that prior to reaching BUG_ON. Alexey Khoroshilov addressed the potential security issues as follows. "An ability to trigger a BUG_ON assert by mounting a crafted image is usually considered as a local denial of service [1-3]. As far as I understand, the reason is that some kernel data may become inconsistent that can lead to further problems. [1] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-3353 [2] http://www.openwall.com/lists/oss-security/2011/06/24/4 [3] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-2928 etc." Reported-by: Andrey Tsyvarev <tsyvarev@ispras.ru> Cc: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 6ebdba1..64755f4 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1609,6 +1609,11 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
struct node_info old_ni, new_ni;
struct page *ipage;
+ get_node_info(sbi, ino, &old_ni);
+ if (unlikely(old_ni.blk_addr != NULL_ADDR))
+ return -EINVAL;
ipage = grab_cache_page(NODE_MAPPING(sbi), ino);
if (!ipage)
return -ENOMEM;
@@ -1616,7 +1621,6 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
/* Should not use this inode from free nid list */
remove_free_nid(NM_I(sbi), ino);
- get_node_info(sbi, ino, &old_ni);
fill_node_footer(ipage, ino, ino, 0, true);