On 17.08.21 12:45, Christian Storm wrote: > Hi Jan, > >>> buffer is AllocatePool()'d but not FreePool()'d on error >>> conditions, resulting in a memory leak. Fix it by calling >>> FreePool() on error exit paths. >>> >>> Signed-off-by: Christian Storm <[email protected]> >>> --- >>> utils.c | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/utils.c b/utils.c >>> index 6238c8b..42ff741 100644 >>> --- a/utils.c >>> +++ b/utils.c >>> @@ -89,10 +89,12 @@ CHAR16 *get_volume_custom_label(EFI_FILE_HANDLE fh) >>> fh->Open, 5, fh, &tmp, L"EFILABEL", EFI_FILE_MODE_READ, >>> EFI_FILE_ARCHIVE | EFI_FILE_HIDDEN | EFI_FILE_SYSTEM); >>> if (status != EFI_SUCCESS) { >>> + (VOID)FreePool(buffer); >>> return NULL; >>> } >>> status = uefi_call_wrapper(tmp->Read, 3, tmp, &buffsize, buffer); >>> if (status != EFI_SUCCESS) { >>> + (VOID)FreePool(buffer); >>> return NULL; >>> } >>> buffer[buffsize/sizeof(CHAR16)] = L'\0'; >>> >> >> Why "(VOID)"? > > Since I'm ignoring the return code and want to make this fact explicit. > There are two possible return codes from FreePool(): > EFI_SUCCESS → The memory was returned to the system. > EFI_INVALID_PARAMETER → Buffer was invalid. > The first one is not interesting, and the second one does not happen, > so I've opted for ignoring it altogether. > >> We are not doing this so far. > > We are, in fact in several places, grep for "(void)" or look at your > commit d6875df in which you fixed up lowercase (void) → (VOID). > > That said, I can drop the prefixing (VOID), I don't care too much but > I do think explicitness helps, particular in critical components such > as a bootloader. >
FreePool() is so far handled like free(), thus without voiding any return value. I'll drop it here for now. If we want it back, it has to be done consistently. Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "EFI Boot Guard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/efibootguard-dev/ece110e2-6a5c-d097-257e-d75e3b5cde27%40siemens.com.
