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| author | Peter Maydell | 2022-07-25 16:05:15 +0200 |
|---|---|---|
| committer | Alex Bennée | 2022-07-29 10:48:01 +0200 |
| commit | fed49cdf6a721d76f9ac1cf76fd05b3fbd8b4892 (patch) | |
| tree | 54c9a32c61e1edcf3f7d5c35ca721e1d1dccecec /semihosting | |
| parent | semihosting: Don't copy buffer after console_write() (diff) | |
| download | qemu-fed49cdf6a721d76f9ac1cf76fd05b3fbd8b4892.tar.gz qemu-fed49cdf6a721d76f9ac1cf76fd05b3fbd8b4892.tar.xz qemu-fed49cdf6a721d76f9ac1cf76fd05b3fbd8b4892.zip | |
semihosting: Check for errors on SET_ARG()
The SET_ARG() macro returns an error indication; we check this in the
TARGET_SYS_GET_CMDLINE case but not when we use it in implementing
TARGET_SYS_ELAPSED. Check for and handle the errors via the do_fault
codepath, and update the comment documenting the SET_ARG() and
GET_ARG() macros to note how they handle memory access errors.
Resolves: Coverity CID 1490287
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220719121110.225657-4-peter.maydell@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220725140520.515340-9-alex.bennee@linaro.org>
Diffstat (limited to 'semihosting')
| -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; |