diff options
| author | Yufen Yu <yuyufen@huawei.com> | 2019-10-30 11:47:02 +0100 |
|---|---|---|
| committer | Song Liu <songliubraving@fb.com> | 2019-11-12 01:32:22 +0100 |
| commit | 228fc7d76db68732677230a3c64337908fd298e3 (patch) | |
| tree | 6c92664f7db4b1f0e5a687b7415a356e38c6c8ae | |
| parent | md/raid1: avoid soft lockup under high load (diff) | |
| download | linux-228fc7d76db68732677230a3c64337908fd298e3.tar.xz linux-228fc7d76db68732677230a3c64337908fd298e3.zip | |
md: avoid invalid memory access for array sb->dev_roles
we need to gurantee 'desc_nr' valid before access array
of sb->dev_roles.
In addition, we should avoid .load_super always return '0'
when level is LEVEL_MULTIPATH, which is not expected.
Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1487373 ("Memory - illegal accesses")
Fixes: 6a5cb53aaa4e ("md: no longer compare spare disk superblock events in super_load")
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
| -rw-r--r-- | drivers/md/md.c | 51 |
1 files changed, 20 insertions, 31 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 6f0ecfe8eab2..805b33e27496 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1105,6 +1105,7 @@ static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE]; mdp_super_t *sb; int ret; + bool spare_disk = true; /* * Calculate the position of the superblock (512byte sectors), @@ -1155,13 +1156,15 @@ static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor else rdev->desc_nr = sb->this_disk.number; + /* not spare disk, or LEVEL_MULTIPATH */ + if (sb->level == LEVEL_MULTIPATH || + (rdev->desc_nr >= 0 && + sb->disks[rdev->desc_nr].state & + ((1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))) + spare_disk = false; + if (!refdev) { - /* - * Insist on good event counter while assembling, except - * for spares (which don't need an event count) - */ - if (sb->disks[rdev->desc_nr].state & ( - (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE))) + if (!spare_disk) ret = 1; else ret = 0; @@ -1181,13 +1184,7 @@ static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor ev1 = md_event(sb); ev2 = md_event(refsb); - /* - * Insist on good event counter while assembling, except - * for spares (which don't need an event count) - */ - if (sb->disks[rdev->desc_nr].state & ( - (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)) && - (ev1 > ev2)) + if (!spare_disk && ev1 > ev2) ret = 1; else ret = 0; @@ -1547,7 +1544,7 @@ static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_ sector_t sectors; char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE]; int bmask; - __u64 role; + bool spare_disk = true; /* * Calculate the position of the superblock in 512byte sectors. @@ -1681,17 +1678,16 @@ static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_ sb->level != 0) return -EINVAL; - role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]); + /* not spare disk, or LEVEL_MULTIPATH */ + if (sb->level == cpu_to_le32(LEVEL_MULTIPATH) || + (rdev->desc_nr >= 0 && + rdev->desc_nr < le32_to_cpu(sb->max_dev) && + (le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < MD_DISK_ROLE_MAX || + le16_to_cpu(sb->dev_roles[rdev->desc_nr]) == MD_DISK_ROLE_JOURNAL))) + spare_disk = false; if (!refdev) { - /* - * Insist of good event counter while assembling, except for - * spares (which don't need an event count) - */ - if (rdev->desc_nr >= 0 && - rdev->desc_nr < le32_to_cpu(sb->max_dev) && - (role < MD_DISK_ROLE_MAX || - role == MD_DISK_ROLE_JOURNAL)) + if (!spare_disk) ret = 1; else ret = 0; @@ -1711,14 +1707,7 @@ static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_ ev1 = le64_to_cpu(sb->events); ev2 = le64_to_cpu(refsb->events); - /* - * Insist of good event counter while assembling, except for - * spares (which don't need an event count) - */ - if (rdev->desc_nr >= 0 && - rdev->desc_nr < le32_to_cpu(sb->max_dev) && - (role < MD_DISK_ROLE_MAX || - role == MD_DISK_ROLE_JOURNAL) && ev1 > ev2) + if (!spare_disk && ev1 > ev2) ret = 1; else ret = 0; |