On 2022/5/17 8:46, Jaegeuk Kim wrote:

On 05/15, Chao Yu wrote:

...

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

---

v3:

• clean up commit message suggested by Bagas Sanjaya. fs/f2fs/f2fs.h | 8 ++++++++ fs/f2fs/inode.c | 3 +-- 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 492af5b96de1..0dc2461ef02c 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -4126,6 +4126,14 @@ static inline void f2fs_set_encrypted_inode(struct inode *inode) */ static inline bool f2fs_post_read_required(struct inode *inode) {

• /*

• * used by sanity_check_inode(), when disk layout fields has not
  

• * been synchronized to inmem fields.
  

• */
  

• if (S_ISREG(inode->i_mode) && (file_is_encrypt(inode) ||

• F2FS_I(inode)->i_flags & F2FS_COMPR_FL ||
  

• file_is_verity(inode)))
  

• return true;
  

Again, I prefer to check this in sanity_check_inode(), since we don't need to check all the time here.

Sure, how about adding a new parameter for f2fs_may_inline_data() to indicate its caller is sanity_check_inode(), and do the checks here only for such path?

Thanks,

...

return f2fs_encrypted_file(inode) || fsverity_active(inode) || f2fs_compressed_file(inode); } diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 2fce8fa0dac8..5e494c98e3c2 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -276,8 +276,7 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page) } }

• if (f2fs_has_inline_data(inode) &&

• 	(!S_ISREG(inode->i_mode) && !S_ISLNK(inode->i_mode))) {
  

• if (f2fs_has_inline_data(inode) && !f2fs_may_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);

-- 2.32.0