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| author |   Artem Savkov <asavkov@redhat.com> | 2016-07-21 13:32:04 +0200 |
|---|---|---|
| committer |   Trond Myklebust <trond.myklebust@primarydata.com> | 2016-07-22 15:14:21 -0400 |
| commit | 297fae4d0bee5d683533f3324baf1b363e7b48bf (patch) | |
| tree | dcb38bff8298ea9cb0dd8bfcccb42d05c83372ba /fs/nfs/blocklayout | |
| parent | nfs/blocklayout: Check max uuids and devices before decoding (diff) | |
| download | linux-dev-297fae4d0bee5d683533f3324baf1b363e7b48bf.tar.xz linux-dev-297fae4d0bee5d683533f3324baf1b363e7b48bf.zip | |
Fix NULL pointer dereference in bl_free_device().
When bl_parse_deviceid() fails in bl_alloc_deviceid_node() on
blkdev_get_by_*() step we get an pnfs_block_dev struct that is
uninitialized except for bdev field which is set to whatever error
blkdev_get_by_*() returns. bl_free_device() then tries to call
blkdev_put() if bdev is not 0 resulting in a wrong pointer dereference.
Fixing this by setting bdev in struct pnfs_block_dev only if we didn't
get an error from blkdev_get_by_*().
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'fs/nfs/blocklayout')
| -rw-r--r-- | fs/nfs/blocklayout/dev.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c index 118252fd1d64..a69ef4e9c24c 100644 --- a/fs/nfs/blocklayout/dev.c +++ b/fs/nfs/blocklayout/dev.c @@ -235,18 +235,20 @@ bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d, struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) { struct pnfs_block_volume *v = &volumes[idx]; + struct block_device *bdev; dev_t dev; dev = bl_resolve_deviceid(server, v, gfp_mask); if (!dev) return -EIO; - d->bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL); - if (IS_ERR(d->bdev)) { + bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL); + if (IS_ERR(bdev)) { printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n", - MAJOR(dev), MINOR(dev), PTR_ERR(d->bdev)); - return PTR_ERR(d->bdev); + MAJOR(dev), MINOR(dev), PTR_ERR(bdev)); + return PTR_ERR(bdev); } + d->bdev = bdev; d->len = i_size_read(d->bdev->bd_inode); @@ -350,17 +352,19 @@ bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d, struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask) { struct pnfs_block_volume *v = &volumes[idx]; + struct block_device *bdev; const struct pr_ops *ops; int error; if (!bl_validate_designator(v)) return -EINVAL; - d->bdev = bl_open_dm_mpath_udev_path(v); - if (IS_ERR(d->bdev)) - d->bdev = bl_open_udev_path(v); - if (IS_ERR(d->bdev)) - return PTR_ERR(d->bdev); + bdev = bl_open_dm_mpath_udev_path(v); + if (IS_ERR(bdev)) + bdev = bl_open_udev_path(v); + if (IS_ERR(bdev)) + return PTR_ERR(bdev); + d->bdev = bdev; d->len = i_size_read(d->bdev->bd_inode); d->map = bl_map_simple; |