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| author | Chao Yu <yuchao0@huawei.com> | 2019-04-15 15:28:35 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2019-05-08 21:23:08 -0700 |
| commit | b42b179bda9ff11075a6fc2bac4d9e400513679a (patch) | |
| tree | 3f07e4e19355788d65115f42fb62cf53c25a6be7 | |
| parent | 8b6810f8acfe429fde7c7dad4714692cc5f75651 (diff) | |
| download | linux-b42b179bda9ff11075a6fc2bac4d9e400513679a.tar.gz linux-b42b179bda9ff11075a6fc2bac4d9e400513679a.tar.bz2 linux-b42b179bda9ff11075a6fc2bac4d9e400513679a.zip | |
f2fs: fix to do checksum even if inode page is uptodate
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203221
- Overview
When mounting the attached crafted image and running program, this error is reported.
The image is intentionally fuzzed from a normal f2fs image for testing and I enabled option CONFIG_F2FS_CHECK_FS on.
- Reproduces
cc poc_07.c
mkdir test
mount -t f2fs tmp.img test
cp a.out test
cd test
sudo ./a.out
- Messages
kernel BUG at fs/f2fs/node.c:1279!
RIP: 0010:read_node_page+0xcf/0xf0
Call Trace:
__get_node_page+0x6b/0x2f0
f2fs_iget+0x8f/0xdf0
f2fs_lookup+0x136/0x320
__lookup_slow+0x92/0x140
lookup_slow+0x30/0x50
walk_component+0x1c1/0x350
path_lookupat+0x62/0x200
filename_lookup+0xb3/0x1a0
do_fchmodat+0x3e/0xa0
__x64_sys_chmod+0x12/0x20
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
On below paths, we can have opportunity to readahead inode page
- gc_node_segment -> f2fs_ra_node_page
- gc_data_segment -> f2fs_ra_node_page
- f2fs_fill_dentries -> f2fs_ra_node_page
Unlike synchronized read, on readahead path, we can set page uptodate
before verifying page's checksum, then read_node_page() will trigger
kernel panic once it encounters a uptodated page w/ incorrect checksum.
So considering readahead scenario, we have to do checksum each time
when loading inode page even if it is uptodated.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| -rw-r--r-- | fs/f2fs/inode.c | 4 | ||||
| -rw-r--r-- | fs/f2fs/node.c | 7 |
2 files changed, 6 insertions, 5 deletions
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 4edd6f2bb491..b53952a15ffa 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -177,8 +177,8 @@ bool f2fs_inode_chksum_verify(struct f2fs_sb_info *sbi, struct page *page) if (provided != calculated) f2fs_msg(sbi->sb, KERN_WARNING, - "checksum invalid, ino = %x, %x vs. %x", - ino_of_node(page), provided, calculated); + "checksum invalid, nid = %lu, ino_of_node = %x, %x vs. %x", + page->index, ino_of_node(page), provided, calculated); return provided == calculated; } diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index d45ecef75116..5452a6e340da 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1281,9 +1281,10 @@ static int read_node_page(struct page *page, int op_flags) int err; if (PageUptodate(page)) { -#ifdef CONFIG_F2FS_CHECK_FS - f2fs_bug_on(sbi, !f2fs_inode_chksum_verify(sbi, page)); -#endif + if (!f2fs_inode_chksum_verify(sbi, page)) { + ClearPageUptodate(page); + return -EBADMSG; + } return LOCKED_PAGE; } |