Commit 6da67de6 authored by Ladi Prosek's avatar Ladi Prosek Committed by Paolo Bonzini

memory: don't sign-extend 32-bit writes

ldl_p has a signed return type so assigning it to uint64_t implicitly
sign-extends the value. This results in devices with min_access_size = 8
seeing unexpected values passed to their write handlers.

Example: guest performs a 32-bit write of 0x80000000 to an mmio region
and the handler receives 0xFFFFFFFF80000000 in its value argument.
Signed-off-by: 's avatarLadi Prosek <lprosek@redhat.com>
Message-Id: <1485440557-10384-1-git-send-email-lprosek@redhat.com>
Signed-off-by: 's avatarPaolo Bonzini <pbonzini@redhat.com>
parent 777357d7
......@@ -2630,7 +2630,7 @@ static MemTxResult address_space_write_continue(AddressSpace *as, hwaddr addr,
break;
case 4:
/* 32 bit write access */
val = ldl_p(buf);
val = (uint32_t)ldl_p(buf);
result |= memory_region_dispatch_write(mr, addr1, val, 4,
attrs);
break;
......
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