[PATCH] f2fs: avoid GC causing encrypted file corrupted

From: Chao Yu
Date: Mon Nov 12 2018 - 22:16:39 EST


Jaegeuk,

On 2018/9/18 21:21, Chao Yu wrote:
> On 2018/9/18 20:39, Yunlong Song wrote:
>> The encrypted file may be corrupted by GC in following case:
>>
>> Time 1: | segment 1 blkaddr = A | GC -> | segment 2 blkaddr = B |
>> Encrypted block 1 is moved from blkaddr A of segment 1 to blkaddr B of
>> segment 2,
>>
>> Time 2: | segment 1 blkaddr = B | GC -> | segment 3 blkaddr = C |
>>
>> Before page 1 is written back and if segment 2 become a victim, then
>> page 1 is moved from blkaddr B of segment 2 to blkaddr Cof segment 3,
>> during the GC process of Time 2, f2fs should wait for page 1 written back
>> before reading it, or move_data_block will read a garbage block from
>> blkaddr B since page is not written back to blkaddr B yet.
>>
>> Commit 6aa58d8a ("f2fs: readahead encrypted block during GC") introduce
>> ra_data_block to read encrypted block, but it forgets to add
>> f2fs_wait_on_page_writeback to avoid racing between GC and flush.
>>
>> Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
>
> Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>

I've reviewed this patch, could you add missing tag in the patch located in
dev-test branch?

Thanks,

>
> Thanks,
>
> .
>