56 lines
1.9 KiB
Diff
56 lines
1.9 KiB
Diff
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From 0ef562a4b5da6bc1f16b2ea801b228acafd033d8 Mon Sep 17 00:00:00 2001
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From: Alan Modra <amodra@gmail.com>
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Date: Tue, 10 Dec 2019 23:02:37 +1030
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Subject: [PATCH] ubsan: cr16: left shift cannot be represented in type 'int'
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This was:
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unsigned long mask = SBM (instruction->match_bits);
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with
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#define SBM(offs) ((((1 << (32 - offs)) -1) << (offs)))
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Well, there are a couple of problems. Firstly, the expression uses
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int values (1 rather than 1u or 1ul) resulting in the ubsan error, and
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secondly, a zero offs will result in a 32-bit shift which is undefined
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if ints are only 32 bits.
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* cr16-dis.c (EXTRACT, SBM): Rewrite.
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(cr16_match_opcode): Delete duplicate bcond test.
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---
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opcodes/ChangeLog | 5 +++++
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opcodes/cr16-dis.c | 11 ++++-------
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2 files changed, 9 insertions(+), 7 deletions(-)
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diff --git a/opcodes/cr16-dis.c b/opcodes/cr16-dis.c
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index 65cf91c..68fbe42 100644
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--- a/opcodes/cr16-dis.c
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+++ b/opcodes/cr16-dis.c
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@@ -30,11 +30,11 @@
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/* Extract 'n_bits' from 'a' starting from offset 'offs'. */
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#define EXTRACT(a, offs, n_bits) \
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- (n_bits == 32 ? (((a) >> (offs)) & 0xffffffffL) \
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- : (((a) >> (offs)) & ((1 << (n_bits)) -1)))
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+ (((a) >> (offs)) & ((1ul << ((n_bits) - 1) << 1) - 1))
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-/* Set Bit Mask - a mask to set all bits starting from offset 'offs'. */
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-#define SBM(offs) ((((1 << (32 - offs)) -1) << (offs)))
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+/* Set Bit Mask - a mask to set all bits in a 32-bit word starting
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+ from offset 'offs'. */
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+#define SBM(offs) ((1ul << 31 << 1) - (1ul << (offs)))
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typedef struct
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{
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@@ -329,9 +329,6 @@ cr16_match_opcode (void)
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while (instruction >= cr16_instruction)
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{
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mask = build_mask ();
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- /* Adjust mask for bcond with 32-bit size instruction */
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- if ((IS_INSN_MNEMONIC("b") && instruction->size == 2))
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- mask = 0xff0f0000;
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if ((doubleWord & mask) == BIN (instruction->match,
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instruction->match_bits))
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--
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2.9.3
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