Description: NULL pointer dereference in xfs_bmap_extents_to_btree() when mounting and operating a crafted image
References:
 https://bugzilla.kernel.org/show_bug.cgi?id=199915
 https://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git/commit/?h=for-next&id=23fcb3340d033d9f081e21e6c12c2db7eaa541d3
Notes:
 bwh> Upstream fix depends on (at least) commit 71493b839e29
 bwh> "xfs: move inode fork verifiers to xfs_dinode_verify".  I think
 bwh> this is more trouble than it's worth to backport.
Bugs:
upstream: released (4.18-rc3) [23fcb3340d033d9f081e21e6c12c2db7eaa541d3]
5.10-upstream-stable: N/A "Fixed before branch point"
4.19-upstream-stable: N/A "Fixed before branch point"
4.9-upstream-stable: needed
3.16-upstream-stable: ignored "Too risky to backport"
sid: released (4.18.6-1)
5.10-bullseye-security: N/A "Fixed before branching point"
4.19-buster-security: N/A "Fixed before branching point"
4.9-stretch-security: ignored "EOL"
3.16-jessie-security: ignored "Too risky to backport"