Commit 702a779e authored May 23, 2023 by Ray Chin

Fix overflow issue when computing ideal size of scratch partition

The type of f_frsize is `unsigned long` which is 32 bit for some system so it will overflow after multiplied by f_bfree. This solution adds one more type casting to ensure the type is 64 bit unsigned integer during the computing.

Bug: 281599020
Test: adb root; adb shell disable-verity
Change-Id: I377ed722d5e245c235c3ae12ff66ac7e91d1d6e8

parent 34de7475

fs_mgr/fs_mgr_overlayfs.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -1083,7 +1083,7 @@ static inline uint64_t GetIdealDataScratchSize() {
		return 0;
		}

		auto ideal_size = std::min(super_info.size, uint64_t(s.f_frsize * s.f_bfree * 0.85));
		auto ideal_size = std::min(super_info.size, uint64_t(uint64_t(s.f_frsize) * s.f_bfree * 0.85));

		// Align up to the filesystem block size.
		if (auto remainder = ideal_size % s.f_bsize; remainder > 0) {