iommu/vt-d: Check for allocation failure in aux_detach_device()

mainline inclusion
from mainline-v5.13-rc4
commit 1a590a1c
category: bugfix
bugzilla: 108082
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1a590a1c8bf46bf80ea12b657ca44c345531ac80



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In current kernels small allocations never fail, but checking for
allocation failure is the correct thing to do.

Fixes: 18abda7a ("iommu/vt-d: Fix general protection fault in aux_detach_device()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/YJuobKuSn81dOPLd@mwanda
Link: https://lore.kernel.org/r/20210519015027.108468-2-baolu.lu@linux.intel.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>