misc: sgi-gru: fix use-after-free error in gru_set_context_option, gru_fault...

misc: sgi-gru: fix use-after-free error in gru_set_context_option, gru_fault and gru_handle_user_call_os

mainline inclusion
from mainline-v6.2-rc1
commit 643a16a0
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5UBUF
CVE: CVE-2022-3424

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=643a16a0eb1d6ac23744bb6e90a00fc21148a9dc



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In some bad situation, the gts may be freed gru_check_chiplet_assignment.
The call chain can be gru_unload_context->gru_free_gru_context->gts_drop
and kfree finally. However, the caller didn't know if the gts is freed
or not and use it afterwards. This will trigger a Use after Free bug.

Fix it by introducing a return value to see if it's in error path or not.
Free the gts in caller if gru_check_chiplet_assignment check failed.

Fixes: 55484c45 ("gru: allow users to specify gru chiplet 2")
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Acked-by: Dimitri Sivanich <sivanich@hpe.com>
Link: https://lore.kernel.org/r/20221110035033.19498-1-zyytlz.wz@163.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Reviewed-by: Kuohai Xu <xukuohai@huawei.com>
Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>