From c3ade30ac1dd8f4b54928309570ab3513905e65a Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 30 Aug 2024 18:34:50 +0100 Subject: hw/m68k/mcf5208: Avoid shifting off end of integer In m5208_sys_read(), we have a loop of n from 0 to 31, and we calculate (2u << n). For the n == 31 iteration this will shift off the top of the unsigned 32 bit integer. This is harmless, because we're going to stop the loop with n == 31 anyway, but we can avoid the error by using 64-bit arithmetic here. (The SDCS0 register is documented at https://www.nxp.com/docs/en/reference-manual/MCF5208RM.pdf section 18.4.5; we want the lower 5 bits to indicate the RAM size, where 31 == 4GB, 30 == 2GB, and so on down. As it happens, the layout of the mcf5208evb board memory map means it doesn't make sense to have more than 1GB of RAM in any case.) Resolves: Coverity CID 1547727 Signed-off-by: Peter Maydell Reviewed-by: Thomas Huth Message-ID: <20240830173452.2086140-2-peter.maydell@linaro.org> Signed-off-by: Thomas Huth --- hw/m68k/mcf5208.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'hw/m68k') diff --git a/hw/m68k/mcf5208.c b/hw/m68k/mcf5208.c index ec14096..0ad347d 100644 --- a/hw/m68k/mcf5208.c +++ b/hw/m68k/mcf5208.c @@ -158,7 +158,7 @@ static uint64_t m5208_sys_read(void *opaque, hwaddr addr, { int n; for (n = 0; n < 32; n++) { - if (current_machine->ram_size < (2u << n)) { + if (current_machine->ram_size < (2ULL << n)) { break; } } -- cgit v1.1