Le 03/03/2017 à 16:50, Peter Maydell a écrit : > In get_field(), we take an 'unsigned char' value and shift it left, > which implicitly promotes it to 'signed int', before ORing it into an > 'unsigned long' type. If 'unsigned long' is 64 bits then this will > result in a sign extension and the top 32 bits of the result will be > 1s. Add explicit casts to unsigned long before shifting to prevent > this. > > (Spotted by Coverity, CID 715697.) > > Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
Reviewed-by: Laurent Vivier <laur...@vivier.eu> > --- > disas/m68k.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/disas/m68k.c b/disas/m68k.c > index 073abb9..61b689e 100644 > --- a/disas/m68k.c > +++ b/disas/m68k.c > @@ -4685,10 +4685,11 @@ get_field (const unsigned char *data, enum > floatformat_byteorders order, > /* This is the last byte; zero out the bits which are not part of > this field. */ > result |= > - (*(data + cur_byte) & ((1 << (len - cur_bitshift)) - 1)) > + (unsigned long)(*(data + cur_byte) > + & ((1 << (len - cur_bitshift)) - 1)) > << cur_bitshift; > else > - result |= *(data + cur_byte) << cur_bitshift; > + result |= (unsigned long)*(data + cur_byte) << cur_bitshift; > cur_bitshift += FLOATFORMAT_CHAR_BIT; > if (order == floatformat_little) > ++cur_byte; >
