mainline inclusion from mainline-v6.7-rc1 commit 4d18b5a57b16c21cf868369ca555068722c32b2d category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9195H CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
-------------------------------------------------
After running fsstress on ubifs for a long time, UBI(16384 blocks, fastmap takes 2 blocks) has an erase block with different erase counters displayed from two views:
From ubiscan view: PEB 8031 has erase counter 31581 ========================================================= from to count min avg max --------------------------------------------------------- 0 .. 9: 0 0 0 0 10 .. 99: 0 0 0 0 100 .. 999: 16383 290 315 781 1000 .. 9999: 0 0 0 0 10000 .. 99999: 1 31581 31581 31581 100000 .. inf: 0 0 0 0 --------------------------------------------------------- Total : 16384 290 317 31581
From detailed_erase_block_info view: PEB 8031 has erase counter 7 physical_block_number erase_count 8030 421 8031 7 # mem info is different from disk info 8032 434 8033 425 8034 431
Following process missed updating erase counter in wl_entry(in memory): ubi_update_fastmap for (i = 1; i < new_fm->used_blocks; i++) // update fastmap data if (!tmp_e) if (old_fm && old_fm->e[i]) erase_block(ubi, old_fm->e[i]->pnum) ret = ubi_io_sync_erase(ubi, pnum, 0) ec = be64_to_cpu(ec_hdr->ec) ec += ret ec_hdr->ec = cpu_to_be64(ec) ubi_io_write_ec_hdr(ubi, pnum, ec_hdr) // ec is updated on flash // ec is not updated in old_fm->e[i] (in memory)
Fix it by passing wl_enter into erase_block() and updating erase counter in erase_block().
Fixes: dbb7d2a88d2a ("UBI: Add fastmap core") Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Signed-off-by: Richard Weinberger richard@nod.at --- drivers/mtd/ubi/fastmap.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-)
diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c index 28c8151a0725..f8c230acc55e 100644 --- a/drivers/mtd/ubi/fastmap.c +++ b/drivers/mtd/ubi/fastmap.c @@ -1392,11 +1392,12 @@ static int ubi_write_fastmap(struct ubi_device *ubi, /** * erase_block - Manually erase a PEB. * @ubi: UBI device object - * @pnum: PEB to be erased + * @e: the physical eraseblock to erase * - * Returns the new EC value on success, < 0 indicates an internal error. + * This function returns zero in case of success and a negative error code in + * case of failure. */ -static int erase_block(struct ubi_device *ubi, int pnum) +static int erase_block(struct ubi_device *ubi, struct ubi_wl_entry *e) { int ret; struct ubi_ec_hdr *ec_hdr; @@ -1406,7 +1407,7 @@ static int erase_block(struct ubi_device *ubi, int pnum) if (!ec_hdr) return -ENOMEM;
- ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0); + ret = ubi_io_read_ec_hdr(ubi, e->pnum, ec_hdr, 0); if (ret < 0) goto out; else if (ret && ret != UBI_IO_BITFLIPS) { @@ -1414,7 +1415,7 @@ static int erase_block(struct ubi_device *ubi, int pnum) goto out; }
- ret = ubi_io_sync_erase(ubi, pnum, 0); + ret = ubi_io_sync_erase(ubi, e->pnum, 0); if (ret < 0) goto out;
@@ -1426,11 +1427,16 @@ static int erase_block(struct ubi_device *ubi, int pnum) }
ec_hdr->ec = cpu_to_be64(ec); - ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr); + ret = ubi_io_write_ec_hdr(ubi, e->pnum, ec_hdr); if (ret < 0) goto out;
- ret = ec; + e->ec = ec; + spin_lock(&ubi->wl_lock); + if (e->ec > ubi->max_ec) + ubi->max_ec = e->ec; + spin_unlock(&ubi->wl_lock); + out: kfree(ec_hdr); return ret; @@ -1576,7 +1582,7 @@ int ubi_update_fastmap(struct ubi_device *ubi)
if (!tmp_e) { if (old_fm && old_fm->e[i]) { - ret = erase_block(ubi, old_fm->e[i]->pnum); + ret = erase_block(ubi, old_fm->e[i]); if (ret < 0) { ubi_err(ubi, "could not erase old fastmap PEB");
@@ -1628,7 +1634,7 @@ int ubi_update_fastmap(struct ubi_device *ubi) if (old_fm) { /* no fresh anchor PEB was found, reuse the old one */ if (!tmp_e) { - ret = erase_block(ubi, old_fm->e[0]->pnum); + ret = erase_block(ubi, old_fm->e[0]); if (ret < 0) { ubi_err(ubi, "could not erase old anchor PEB");
@@ -1640,7 +1646,6 @@ int ubi_update_fastmap(struct ubi_device *ubi) goto err; } new_fm->e[0] = old_fm->e[0]; - new_fm->e[0]->ec = ret; old_fm->e[0] = NULL; } else { /* we've got a new anchor PEB, return the old one */