6.6-stable review patch. If anyone has any objections, please let me know.
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From: Chao Yu chao@kernel.org
[ Upstream commit d3876e34e7e789e2cbdd782360fef2a777391082 ]
In below race condition, dst page may become writeback status in __clone_blkaddrs(), it needs to wait writeback before update, fix it.
Thread A GC Thread - f2fs_move_file_range - filemap_write_and_wait_range(dst) - gc_data_segment - f2fs_down_write(dst) - move_data_page - set_page_writeback(dst_page) - f2fs_submit_page_write - f2fs_up_write(dst) - f2fs_down_write(dst) - __exchange_data_block - __clone_blkaddrs - f2fs_get_new_data_page - memcpy_page
Fixes: 0a2aa8fbb969 ("f2fs: refactor __exchange_data_block for speed up") Signed-off-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/file.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index ee5df9adaf775..7f631a617ee99 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1305,6 +1305,9 @@ static int __clone_blkaddrs(struct inode *src_inode, struct inode *dst_inode, f2fs_put_page(psrc, 1); return PTR_ERR(pdst); } + + f2fs_wait_on_page_writeback(pdst, DATA, true, true); + memcpy_page(pdst, 0, psrc, 0, PAGE_SIZE); set_page_dirty(pdst); set_page_private_gcing(pdst);