f2fs: CVE-2018-13099

f2fs: fix to do sanity check with reserved blkaddr of inline inode

References:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-4.14.y&id=7fb2b50ee59689578d5a712633d1e6755fc98933

Change-Id: I98429a8a2f47bed9486b5ab8e8419bfc0cbb5a5a
Signed-off-by: Andreas Wellving <andreas.wellving@enea.com>

1 files changed, 159 insertions, 0 deletions

diff --git a/patches/cve/CVE-2018-13099-f2fs-fix-to-do-sanity-check-with-reserved-blkaddr-of.patch b/patches/cve/CVE-2018-13099-f2fs-fix-to-do-sanity-check-with-reserved-blkaddr-of.patch
new file mode 100644
index 0000000..c3a750d
--- /dev/null
+++ b/patches/cve/CVE-2018-13099-f2fs-fix-to-do-sanity-check-with-reserved-blkaddr-of.patch
@@ -0,0 +1,159 @@
+From 4dbe38dc386910c668c75ae616b99b823b59f3eb Mon Sep 17 00:00:00 2001
+From: Chao Yu <yuchao0@huawei.com>
+Date: Sat, 30 Jun 2018 18:13:40 +0800
+Subject: [PATCH] f2fs: fix to do sanity check with reserved blkaddr of inline
+ inode
+
+As Wen Xu reported in bugzilla, after image was injected with random data
+by fuzzing, inline inode would contain invalid reserved blkaddr, then
+during inline conversion, we will encounter illegal memory accessing
+reported by KASAN, the root cause of this is when writing out converted
+inline page, we will use invalid reserved blkaddr to update sit bitmap,
+result in accessing memory beyond sit bitmap boundary.
+
+In order to fix this issue, let's do sanity check with reserved block
+address of inline inode to avoid above condition.
+
+https://bugzilla.kernel.org/show_bug.cgi?id=200179
+
+[ 1428.846352] BUG: KASAN: use-after-free in update_sit_entry+0x80/0x7f0
+[ 1428.846618] Read of size 4 at addr ffff880194483540 by task a.out/2741
+
+[ 1428.846855] CPU: 0 PID: 2741 Comm: a.out Tainted: G        W         4.17.0+ #1
+[ 1428.846858] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
+[ 1428.846860] Call Trace:
+[ 1428.846868]  dump_stack+0x71/0xab
+[ 1428.846875]  print_address_description+0x6b/0x290
+[ 1428.846881]  kasan_report+0x28e/0x390
+[ 1428.846888]  ? update_sit_entry+0x80/0x7f0
+[ 1428.846898]  update_sit_entry+0x80/0x7f0
+[ 1428.846906]  f2fs_allocate_data_block+0x6db/0xc70
+[ 1428.846914]  ? f2fs_get_node_info+0x14f/0x590
+[ 1428.846920]  do_write_page+0xc8/0x150
+[ 1428.846928]  f2fs_outplace_write_data+0xfe/0x210
+[ 1428.846935]  ? f2fs_do_write_node_page+0x170/0x170
+[ 1428.846941]  ? radix_tree_tag_clear+0xff/0x130
+[ 1428.846946]  ? __mod_node_page_state+0x22/0xa0
+[ 1428.846951]  ? inc_zone_page_state+0x54/0x100
+[ 1428.846956]  ? __test_set_page_writeback+0x336/0x5d0
+[ 1428.846964]  f2fs_convert_inline_page+0x407/0x6d0
+[ 1428.846971]  ? f2fs_read_inline_data+0x3b0/0x3b0
+[ 1428.846978]  ? __get_node_page+0x335/0x6b0
+[ 1428.846987]  f2fs_convert_inline_inode+0x41b/0x500
+[ 1428.846994]  ? f2fs_convert_inline_page+0x6d0/0x6d0
+[ 1428.847000]  ? kasan_unpoison_shadow+0x31/0x40
+[ 1428.847005]  ? kasan_kmalloc+0xa6/0xd0
+[ 1428.847024]  f2fs_file_mmap+0x79/0xc0
+[ 1428.847029]  mmap_region+0x58b/0x880
+[ 1428.847037]  ? arch_get_unmapped_area+0x370/0x370
+[ 1428.847042]  do_mmap+0x55b/0x7a0
+[ 1428.847048]  vm_mmap_pgoff+0x16f/0x1c0
+[ 1428.847055]  ? vma_is_stack_for_current+0x50/0x50
+[ 1428.847062]  ? __fsnotify_update_child_dentry_flags.part.1+0x160/0x160
+[ 1428.847068]  ? do_sys_open+0x206/0x2a0
+[ 1428.847073]  ? __fget+0xb4/0x100
+[ 1428.847079]  ksys_mmap_pgoff+0x278/0x360
+[ 1428.847085]  ? find_mergeable_anon_vma+0x50/0x50
+[ 1428.847091]  do_syscall_64+0x73/0x160
+[ 1428.847098]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
+[ 1428.847102] RIP: 0033:0x7fb1430766ba
+[ 1428.847103] Code: 89 f5 41 54 49 89 fc 55 53 74 35 49 63 e8 48 63 da 4d 89 f9 49 89 e8 4d 63 d6 48 89 da 4c 89 ee 4c 89 e7 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 56 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 00
+[ 1428.847162] RSP: 002b:00007ffc651d9388 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
+[ 1428.847167] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fb1430766ba
+[ 1428.847170] RDX: 0000000000000001 RSI: 0000000000001000 RDI: 0000000000000000
+[ 1428.847173] RBP: 0000000000000003 R08: 0000000000000003 R09: 0000000000000000
+[ 1428.847176] R10: 0000000000008002 R11: 0000000000000246 R12: 0000000000000000
+[ 1428.847179] R13: 0000000000001000 R14: 0000000000008002 R15: 0000000000000000
+
+[ 1428.847252] Allocated by task 2683:
+[ 1428.847372]  kasan_kmalloc+0xa6/0xd0
+[ 1428.847380]  kmem_cache_alloc+0xc8/0x1e0
+[ 1428.847385]  getname_flags+0x73/0x2b0
+[ 1428.847390]  user_path_at_empty+0x1d/0x40
+[ 1428.847395]  vfs_statx+0xc1/0x150
+[ 1428.847401]  __do_sys_newlstat+0x7e/0xd0
+[ 1428.847405]  do_syscall_64+0x73/0x160
+[ 1428.847411]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
+
+[ 1428.847466] Freed by task 2683:
+[ 1428.847566]  __kasan_slab_free+0x137/0x190
+[ 1428.847571]  kmem_cache_free+0x85/0x1e0
+[ 1428.847575]  filename_lookup+0x191/0x280
+[ 1428.847580]  vfs_statx+0xc1/0x150
+[ 1428.847585]  __do_sys_newlstat+0x7e/0xd0
+[ 1428.847590]  do_syscall_64+0x73/0x160
+[ 1428.847596]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
+
+[ 1428.847648] The buggy address belongs to the object at ffff880194483300
+                which belongs to the cache names_cache of size 4096
+[ 1428.847946] The buggy address is located 576 bytes inside of
+                4096-byte region [ffff880194483300, ffff880194484300)
+[ 1428.848234] The buggy address belongs to the page:
+[ 1428.848366] page:ffffea0006512000 count:1 mapcount:0 mapping:ffff8801f3586380 index:0x0 compound_mapcount: 0
+[ 1428.848606] flags: 0x17fff8000008100(slab|head)
+[ 1428.848737] raw: 017fff8000008100 dead000000000100 dead000000000200 ffff8801f3586380
+[ 1428.848931] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
+[ 1428.849122] page dumped because: kasan: bad access detected
+
+[ 1428.849305] Memory state around the buggy address:
+[ 1428.849436]  ffff880194483400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+[ 1428.849620]  ffff880194483480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+[ 1428.849804] >ffff880194483500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+[ 1428.849985]                                            ^
+[ 1428.850120]  ffff880194483580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+[ 1428.850303]  ffff880194483600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
+[ 1428.850498] ==================================================================
+
+CVE: CVE-2018-13099
+Upstream-Status: Backport
+
+Reported-by: Wen Xu <wen.xu@gatech.edu>
+Signed-off-by: Chao Yu <yuchao0@huawei.com>
+Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
+Signed-off-by: Andreas Wellving <andreas.wellving@enea.com>
+---
+ fs/f2fs/inline.c | 21 +++++++++++++++++++++
+ 1 file changed, 21 insertions(+)
+
+diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
+index 9a245d2..2bcb2d3 100644
+--- a/fs/f2fs/inline.c
++++ b/fs/f2fs/inline.c
+@@ -130,6 +130,16 @@ int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page)
+        if (err)
+                return err;
+ 
++       if (unlikely(dn->data_blkaddr != NEW_ADDR)) {
++               f2fs_put_dnode(dn);
++               set_sbi_flag(fio.sbi, SBI_NEED_FSCK);
++               f2fs_msg(fio.sbi->sb, KERN_WARNING,
++                       "%s: corrupted inline inode ino=%lx, i_addr[0]:0x%x, "
++                       "run fsck to fix.",
++                       __func__, dn->inode->i_ino, dn->data_blkaddr);
++               return -EINVAL;
++       }
++
+        f2fs_bug_on(F2FS_P_SB(page), PageWriteback(page));
+ 
+        f2fs_do_read_inline_data(page, dn->inode_page);
+@@ -363,6 +373,17 @@ static int f2fs_move_inline_dirents(struct inode *dir, struct page *ipage,
+        if (err)
+                goto out;
+ 
++       if (unlikely(dn.data_blkaddr != NEW_ADDR)) {
++               f2fs_put_dnode(&dn);
++               set_sbi_flag(F2FS_P_SB(page), SBI_NEED_FSCK);
++               f2fs_msg(F2FS_P_SB(page)->sb, KERN_WARNING,
++                       "%s: corrupted inline inode ino=%lx, i_addr[0]:0x%x, "
++                       "run fsck to fix.",
++                       __func__, dir->i_ino, dn.data_blkaddr);
++               err = -EINVAL;
++               goto out;
++       }
++
+        f2fs_wait_on_page_writeback(page, DATA, true);
+ 
+        dentry_blk = page_address(page);
+-- 
+
+