FEX-Emu/linux
1
0
Fork 0
mirror of https://github.com/FEX-Emu/linux.git synced 2024-12-29 04:45:05 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

arm64: alternative: Disallow patching instructions using literals

Browse Source 
The alternative code patching doesn't check if the replaced instruction
uses a pc relative literal. This could cause silent corruption in the
instruction stream as the instruction will be executed from a different
address than what it was compiled for. Catch all such cases.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Suzuki K Poulose 2016-09-09 14:07:11 +01:00 committed by Will Deacon
parent c47a1900ad
commit baa763b565
1 changed files with 6 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/arm64/kernel/alternative.c
View File

@ -79,6 +79,12 @@ static u32 get_alt_insn(struct alt_instr *alt, u32 *insnptr, u32 *altinsnptr)
offset = target - (unsigned long)insnptr;
insn = aarch64_set_branch_offset(insn, offset);
}
} else if (aarch64_insn_uses_literal(insn)) {
/*
* Disallow patching unhandled instructions using PC relative
* literal addresses
*/
BUG();
}
return insn;