Description: Invalid pointer dereference in btrfs_root_node() when mounting a crafted btrfs image
References:
 https://bugzilla.kernel.org/show_bug.cgi?id=199847
 https://patchwork.kernel.org/patch/10503403/
 https://patchwork.kernel.org/patch/10503413/
Notes:
 carnil> For 4.18.x branch first commit landed in 4.18.8 but unsure
 carnil> what happened for the second one, resp. not yet checked if
 carnil> that applies.
Bugs:
upstream: released (4.19-rc1) [ba480dd4db9f1798541eb2d1c423fc95feee8d36, 7ef49515fa6727cb4b6f2f5b0ffbc5fc20a9f8c6]
4.19-upstream-stable: N/A "Fixed before branch point"
4.9-upstream-stable: released (4.9.144) [6f33d3d8dca8683a4df94e9944296a1a1a2a6f10, 23eb2f435a07e1e09d48ea10c4a22bc96e16fde6]
3.16-upstream-stable: released (3.16.83) [e3f6c37c31522cc99cea96e0f0f6f536026fb058, b84f82bdb43676854de8c5196bd8738805b892ee]
sid: released (4.18.8-1)
4.19-buster-security: N/A "Fixed before branching point"
4.9-stretch-security: released (4.9.144-1)
3.16-jessie-security: released (3.16.84-1)