提交 1d153a33 编写于 作者: P Peter Maydell

disas/microblaze: Avoid unintended sign extension

In read_insn_microblaze() we assemble 4 bytes into an 'unsigned
long'.  If 'unsigned long' is 64 bits and the high byte has its top
bit set, then C's implicit conversion from 'unsigned char' to 'int'
for the shift will result in an unintended sign extension which sets
the top 32 bits in 'inst'.  Add casts to prevent this.  (Spotted by
Coverity, CID 10054016.)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1488556233-31246-5-git-send-email-peter.maydell@linaro.org
上级 2e3883d0
...@@ -748,9 +748,11 @@ read_insn_microblaze (bfd_vma memaddr, ...@@ -748,9 +748,11 @@ read_insn_microblaze (bfd_vma memaddr,
} }
if (info->endian == BFD_ENDIAN_BIG) if (info->endian == BFD_ENDIAN_BIG)
inst = (ibytes[0] << 24) | (ibytes[1] << 16) | (ibytes[2] << 8) | ibytes[3]; inst = ((unsigned)ibytes[0] << 24) | (ibytes[1] << 16)
| (ibytes[2] << 8) | ibytes[3];
else if (info->endian == BFD_ENDIAN_LITTLE) else if (info->endian == BFD_ENDIAN_LITTLE)
inst = (ibytes[3] << 24) | (ibytes[2] << 16) | (ibytes[1] << 8) | ibytes[0]; inst = ((unsigned)ibytes[3] << 24) | (ibytes[2] << 16)
| (ibytes[1] << 8) | ibytes[0];
else else
abort (); abort ();
......
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