On Wed, Feb 04, 2026 at 04:57:14PM +0300, Dmitry Antipov wrote:
> Since '_parse_integer_limit()' (and so 'simple_strtoull()') is now
> capable to handle overflow, adjust 'memparse()' to handle overflow
> (denoted by ULLONG_MAX) returned from 'simple_strtoull()'. Also
> use 'check_shl_overflow()' to catch an overflow possibly caused
> by processing size suffix and denote it with ULLONG_MAX as well.
Do we have already test cases to cover this?
...
> unsigned long long memparse(const char *ptr, char **retptr)
> {
> char *endptr; /* local pointer to end of parsed string */
>
Shouldn't be an empty line in the definition block.
> + unsigned int shl = 0;
> unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
and it would be better to preserve reversed xmas tree order (to some extent).
char *endptr; /* local pointer to end of parsed string */
unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
unsigned int shl = 0;
> + /* Consume valid suffix even in case of overflow. */
> switch (*endptr) {
> case 'E':
> case 'e':
> - ret <<= 10;
> + shl += 10;
> fallthrough;
> case 'P':
> case 'p':
> - ret <<= 10;
> + shl += 10;
> fallthrough;
> case 'T':
> case 't':
> - ret <<= 10;
> + shl += 10;
> fallthrough;
> case 'G':
> case 'g':
> - ret <<= 10;
> + shl += 10;
> fallthrough;
> case 'M':
> case 'm':
> - ret <<= 10;
> + shl += 10;
> fallthrough;
> case 'K':
> case 'k':
> - ret <<= 10;
> + shl += 10;
> endptr++;
> fallthrough;
> default:
> break;
> }
> + /* If no overflow, apply suffix if any. */
> + if (likely(ret != ULLONG_MAX) && shl) {
Do we need to check for shl? Yes, it will be an additional check below,
but do we care?
> + unsigned long long val;
> + ret = (unlikely(check_shl_overflow(ret, shl, &val))
> + ? ULLONG_MAX : val);
Unneeded parentheses, and ? should be on the previous line.
With that said, I prefer to see the regular conditional instead:
ret = check_shl_overflow(...);
if (unlikely(ret))
ret = ...
else
ret = val;
> + }
> +
> if (retptr)
> *retptr = endptr;
--
With Best Regards,
Andy Shevchenko
