If device is readonly, make f2fs_convert_inline_inode() return EROFS instead of zero, otherwise it may trigger panic during writeback of inline inode's dirty page as below:

f2fs_write_single_data_page+0xbb6/0x1e90 fs/f2fs/data.c:2888 f2fs_write_cache_pages fs/f2fs/data.c:3187 [inline] __f2fs_write_data_pages fs/f2fs/data.c:3342 [inline] f2fs_write_data_pages+0x1efe/0x3a90 fs/f2fs/data.c:3369 do_writepages+0x359/0x870 mm/page-writeback.c:2634 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397 __filemap_fdatawrite_range mm/filemap.c:430 [inline] file_write_and_wait_range+0x1aa/0x290 mm/filemap.c:788 f2fs_do_sync_file+0x68a/0x1ae0 fs/f2fs/file.c:276 generic_write_sync include/linux/fs.h:2806 [inline] f2fs_file_write_iter+0x7bd/0x24e0 fs/f2fs/file.c:4977 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Cc: stable@vger.kernel.org Reported-by: syzbot+848062ba19c8782ca5c8@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-f2fs-devel/000000000000d103ce06174d7ec3@google... Signed-off-by: Chao Yu chao@kernel.org --- fs/f2fs/inline.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c index 0203c3baabb6..1fba5728be70 100644 --- a/fs/f2fs/inline.c +++ b/fs/f2fs/inline.c @@ -221,8 +221,10 @@ int f2fs_convert_inline_inode(struct inode *inode) struct page *ipage, *page; int err = 0;

- if (!f2fs_has_inline_data(inode) || - f2fs_hw_is_readonly(sbi) || f2fs_readonly(sbi->sb)) + if (f2fs_hw_is_readonly(sbi) || f2fs_readonly(sbi->sb)) + return -EROFS; + + if (!f2fs_has_inline_data(inode)) return 0;

err = f2fs_dquot_initialize(inode);