From e1b6935d60a00405e6b5b455a3426d2248cc926c Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Fri, 11 Jun 2010 21:43:28 +0300 Subject: Fix string to uint64_t conversion. Thanks to Denis Excoffier for the bug report. --- src/xzdec/xzdec.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'src/xzdec') diff --git a/src/xzdec/xzdec.c b/src/xzdec/xzdec.c index 8518d362..7f2e0fdc 100644 --- a/src/xzdec/xzdec.c +++ b/src/xzdec/xzdec.c @@ -153,6 +153,9 @@ memlimit_init(void) /// \brief Convert a string to uint64_t /// /// This is rudely copied from src/xz/util.c and modified a little. :-( +/// Since this function is used only for parsing the memory usage limit, +/// this cheats a little and saturates too big values to UINT64_MAX instead +/// of giving an error. /// /// \param max Return value when the string "max" was specified. /// @@ -173,11 +176,17 @@ str_to_uint64(const char *value, uint64_t max) do { // Don't overflow. - if (result > (UINT64_MAX - 9) / 10) + if (result > UINT64_MAX / 10) return UINT64_MAX; result *= 10; - result += *value - '0'; + + // Another overflow check + const uint32_t add = *value - '0'; + if (UINT64_MAX - add < result) + return UINT64_MAX; + + result += add; ++value; } while (*value >= '0' && *value <= '9'); -- cgit v1.2.3