From: Wang YanQing udknight@gmail.com
commit 31a149d5c13c4cbcf97de3435817263a2d8c9d6e upstream.
The commit 2d78aee426d8 ("UBI: simplify LEB write and atomic LEB change code") adds helper function, try_write_vid_and_data(), to simplify the code, but this helper function has bug, it will return 0 (success) when ubi_io_write_vid_hdr() or the ubi_io_write_data() return error number (-EIO, etc), because the return value of ubi_wl_put_peb() will overwrite the original return value.
This issue will cause unexpected data loss issue, because the caller of this function and UBIFS willn't know the data is lost.
Fixes: 2d78aee426d8 ("UBI: simplify LEB write and atomic LEB change code") Cc: stable@vger.kernel.org Signed-off-by: Wang YanQing udknight@gmail.com Reviewed-by: Zhihao Cheng chengzhihao1@huawei.com Signed-off-by: Richard Weinberger richard@nod.at Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/mtd/ubi/eba.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-)
--- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -943,7 +943,7 @@ static int try_write_vid_and_data(struct int offset, int len) { struct ubi_device *ubi = vol->ubi; - int pnum, opnum, err, vol_id = vol->vol_id; + int pnum, opnum, err, err2, vol_id = vol->vol_id;
pnum = ubi_wl_get_peb(ubi); if (pnum < 0) { @@ -978,10 +978,19 @@ static int try_write_vid_and_data(struct out_put: up_read(&ubi->fm_eba_sem);
- if (err && pnum >= 0) - err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); - else if (!err && opnum >= 0) - err = ubi_wl_put_peb(ubi, vol_id, lnum, opnum, 0); + if (err && pnum >= 0) { + err2 = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); + if (err2) { + ubi_warn(ubi, "failed to return physical eraseblock %d, error %d", + pnum, err2); + } + } else if (!err && opnum >= 0) { + err2 = ubi_wl_put_peb(ubi, vol_id, lnum, opnum, 0); + if (err2) { + ubi_warn(ubi, "failed to return physical eraseblock %d, error %d", + opnum, err2); + } + }
return err; }