From: Chao Yu yuchao0@huawei.com
[ Upstream commit 95978caa138948054e06d00bfc3432b518699f1b ]
In compress cluster, if physical block number is less than logic page number, race condition will cause use-after-free issue as described below:
- f2fs_write_compressed_pages - fio.page = cic->rpages[0]; - f2fs_outplace_write_data - f2fs_compress_write_end_io - kfree(cic->rpages); - kfree(cic); - fio.page = cic->rpages[1];
f2fs_write_multi_pages+0xfd0/0x1a98 f2fs_write_data_pages+0x74c/0xb5c do_writepages+0x64/0x108 __writeback_single_inode+0xdc/0x4b8 writeback_sb_inodes+0x4d0/0xa68 __writeback_inodes_wb+0x88/0x178 wb_writeback+0x1f0/0x424 wb_workfn+0x2f4/0x574 process_one_work+0x210/0x48c worker_thread+0x2e8/0x44c kthread+0x110/0x120 ret_from_fork+0x10/0x18
Fixes: 4c8ff7095bef ("f2fs: support data compression") Signed-off-by: Chao Yu yuchao0@huawei.com Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/compress.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c index c847523ab4a2e..927db1205bd81 100644 --- a/fs/f2fs/compress.c +++ b/fs/f2fs/compress.c @@ -845,7 +845,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
blkaddr = datablock_addr(dn.inode, dn.node_page, dn.ofs_in_node); - fio.page = cic->rpages[i]; + fio.page = cc->rpages[i]; fio.old_blkaddr = blkaddr;
/* cluster header */