Messages in this thread Patch in this message | | | From | Borislav Petkov <> | Subject | [PATCH] x86/sev-es: Remove subtraction of res variable | Date | Tue, 23 Feb 2021 12:11:30 +0100 |
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From: Borislav Petkov <bp@suse.de>
vc_decode_insn() calls copy_from_kernel_nofault() by way of vc_fetch_insn_kernel() to fetch 15 bytes max of opcodes to decode.
copy_from_kernel_nofault() returns negative on error and 0 on success. The error case is handled by returning ES_EXCEPTION.
In the success case, the ret variable which contains the return value is 0 so there's no need to subtract it from MAX_INSN_SIZE when initializing the insn buffer for further decoding. Remove it.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de> --- arch/x86/kernel/sev-es.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 84c1821819af..1e78f4bd7bf2 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -267,7 +267,7 @@ static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) return ES_EXCEPTION; } - insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE - res, 1); + insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE, 1); insn_get_length(&ctxt->insn); } -- 2.29.2
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