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s390/nospec: Correct modules thunk offset calculation

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Fix offset calculation when branch target is more then 2Gb away.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
This commit is contained in:
Vasily Gorbik 2024-01-17 11:50:46 +01:00 committed by Alexander Gordeev
parent 236d70f82b
commit ea84f14d2a
1 changed files with 2 additions and 2 deletions
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4
arch/s390/kernel/nospec-branch.c
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@ -114,10 +114,10 @@ static void __init_or_module __nospec_revert(s32 *start, s32 *end)
type = BRASL_EXPOLINE; /* brasl instruction */
else
continue;
thunk = instr + (*(int *)(instr + 2)) * 2;
thunk = instr + (long)(*(int *)(instr + 2)) * 2;
if (thunk[0] == 0xc6 && thunk[1] == 0x00)
/* exrl %r0,<target-br> */
br = thunk + (*(int *)(thunk + 2)) * 2;
br = thunk + (long)(*(int *)(thunk + 2)) * 2;
else
continue;
if (br[0] != 0x07 || (br[1] & 0xf0) != 0xf0)