From: Wang YanQing udknight@gmail.com

mainline inclusion from mainline-v6.2-rc1 commit 31a149d5c13c4cbcf97de3435817263a2d8c9d6e category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7JO2R CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id...

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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: ZhaoLong Wang wangzhaolong1@huawei.com --- drivers/mtd/ubi/eba.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c index 0edecfdbd01f..b4cdf2351cac 100644 --- a/drivers/mtd/ubi/eba.c +++ b/drivers/mtd/ubi/eba.c @@ -947,7 +947,7 @@ static int try_write_vid_and_data(struct ubi_volume *vol, int lnum, 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) { @@ -982,10 +982,19 @@ static int try_write_vid_and_data(struct ubi_volume *vol, int lnum, 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; }