[PATCH 5.18 716/879] f2fs: fix to do sanity check for inline inode

Greg Kroah-Hartman
2022-06-08T00:18:41Z

From: Chao Yu <chao@kernel.org>

commit 677a82b44ebf263d4f9a0cfbd576a6ade797a07b upstream.

Yanming reported a kernel bug in Bugzilla kernel [1], which can be
reproduced. The bug message is:

The kernel message is shown below:

kernel BUG at fs/inode.c:611!
Call Trace:
evict+0x282/0x4e0
__dentry_kill+0x2b2/0x4d0
dput+0x2dd/0x720
do_renameat2+0x596/0x970
__x64_sys_rename+0x78/0x90
do_syscall_64+0x3b/0x90

[1] https://bugzilla.kernel.org/show_bug.cgi?id=215895

The bug is due to fuzzed inode has both inline_data and encrypted flags.
During f2fs_evict_inode(), as the inode was deleted by rename(), it
will cause inline data conversion due to conflicting flags. The page
cache will be polluted and the panic will be triggered in clear_inode().

Try fixing the bug by doing more sanity checks for inline data inode in
sanity_check_inode().

Cc: stable@vger.kernel.org
Reported-by: Ming Yan <yanming@tju.edu.cn>
Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/f2fs/f2fs.h | 1 +
fs/f2fs/inline.c | 29 ++++++++++++++++++++++++-----
fs/f2fs/inode.c | 3 +--
3 files changed, 26 insertions(+), 7 deletions(-)

--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4052,6 +4052,7 @@ extern struct kmem_cache *f2fs_inode_ent
* inline.c
*/
bool f2fs_may_inline_data(struct inode *inode);
+bool f2fs_sanity_check_inline_data(struct inode *inode);
bool f2fs_may_inline_dentry(struct inode *inode);
void f2fs_do_read_inline_data(struct page *page, struct page *ipage);
void f2fs_truncate_inline_inode(struct inode *inode,
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -14,21 +14,40 @@
#include "node.h"
#include <trace/events/f2fs.h>

-bool f2fs_may_inline_data(struct inode *inode)
+static bool support_inline_data(struct inode *inode)
{
if (f2fs_is_atomic_file(inode))
return false;
-
if (!S_ISREG(inode->i_mode) && !S_ISLNK(inode->i_mode))
return false;
-
if (i_size_read(inode) > MAX_INLINE_DATA(inode))
return false;
+ return true;
+}
+
+bool f2fs_may_inline_data(struct inode *inode)
+{
+ if (!support_inline_data(inode))
+ return false;
+
+ return !f2fs_post_read_required(inode);
+}

- if (f2fs_post_read_required(inode))
+bool f2fs_sanity_check_inline_data(struct inode *inode)
+{
+ if (!f2fs_has_inline_data(inode))
return false;

- return true;
+ if (!support_inline_data(inode))
+ return true;
+
+ /*
+ * used by sanity_check_inode(), when disk layout fields has not
+ * been synchronized to inmem fields.
+ */
+ return (S_ISREG(inode->i_mode) &&
+ (file_is_encrypt(inode) || file_is_verity(inode) ||
+ (F2FS_I(inode)->i_flags & F2FS_COMPR_FL)));
}

bool f2fs_may_inline_dentry(struct inode *inode)
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -276,8 +276,7 @@ static bool sanity_check_inode(struct in
}
}

- if (f2fs_has_inline_data(inode) &&
- (!S_ISREG(inode->i_mode) && !S_ISLNK(inode->i_mode))) {
+ if (f2fs_sanity_check_inline_data(inode)) {
set_sbi_flag(sbi, SBI_NEED_FSCK);
f2fs_warn(sbi, "%s: inode (ino=%lx, mode=%u) should not have inline_data, run fsck to fix",
__func__, inode->i_ino, inode->i_mode);