diff options
| -rw-r--r-- | semihosting/arm-compat-semi.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c index 1a1e2a6960..d12288fc80 100644 --- a/semihosting/arm-compat-semi.c +++ b/semihosting/arm-compat-semi.c @@ -171,6 +171,12 @@ static LayoutInfo common_semi_find_bases(CPUState *cs) * Read the input value from the argument block; fail the semihosting * call if the memory read fails. Eventually we could use a generic * CPUState helper function here. + * Note that GET_ARG() handles memory access errors by jumping to + * do_fault, so must be used as the first thing done in handling a + * semihosting call, to avoid accidentally leaking allocated resources. + * SET_ARG(), since it unavoidably happens late, instead returns an + * error indication (0 on success, non-0 for error) which the caller + * should check. */ #define GET_ARG(n) do { \ @@ -739,10 +745,14 @@ void do_common_semihosting(CPUState *cs) case TARGET_SYS_ELAPSED: elapsed = get_clock() - clock_start; if (sizeof(target_ulong) == 8) { - SET_ARG(0, elapsed); + if (SET_ARG(0, elapsed)) { + goto do_fault; + } } else { - SET_ARG(0, (uint32_t) elapsed); - SET_ARG(1, (uint32_t) (elapsed >> 32)); + if (SET_ARG(0, (uint32_t) elapsed) || + SET_ARG(1, (uint32_t) (elapsed >> 32))) { + goto do_fault; + } } common_semi_set_ret(cs, 0); break; |