tree aa9ef26490a56a9b6fa973a30f2218a7783bfe8d
parent 81f70ba233d5f660e1ea5fe23260ee323af5d53a
author Martin Schwidefsky <schwidefsky@de.ibm.com> 1455889454 +0100
committer Martin Schwidefsky <schwidefsky@de.ibm.com> 1456129775 +0100

s390/compat: correct restore of high gprs on signal return

git commit 8070361799ae1e3f4ef347bd10f0a508ac10acfb
"s390: add support for vector extension"
broke 31-bit compat processes in regard to signal handling.

The restore_sigregs_ext32() function is used to restore the additional
elements from the user space signal frame. Among the additional elements
are the upper registers halves for 64-bit register support for 31-bit
processes. The copy_from_user that is used to retrieve the high-gprs
array from the user stack uses an incorrect length, 8 bytes instead of
64 bytes. This causes incorrect upper register halves to get loaded.

Cc: stable@vger.kernel.org # 3.8+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>