ext2/3: use prandom_u32() instead of get_random_bytes() (e878167a) · Commits · 戴 / test

Many of the uses of get_random_bytes() do not actually need cryptographically secure random numbers. Replace those uses with a call to prandom_u32(), which is faster and which doesn't consume entropy from the /dev/random driver. The commit has made that for ext4, and i did the same for ext2/3. Signed-off-by:

Zhang Zhen <zhenzhang.zhang@huawei.com> Signed-off-by:

Jan Kara <jack@suse.cz>

fs/ext2/ialloc.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -284,7 +284,7 @@ static int find_group_orlov(struct super_block sb, struct inode parent)
		int best_ndir = inodes_per_group;
		int best_group = -1;

		get_random_bytes(&group, sizeof(group));
		group = prandom_u32();
		parent_group = (unsigned)group % ngroups;
		for (i = 0; i < ngroups; i++) {
		group = (parent_group + i) % ngroups;

fs/ext3/ialloc.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -215,7 +215,7 @@ static int find_group_orlov(struct super_block sb, struct inode parent)
		int best_ndir = inodes_per_group;
		int best_group = -1;

		get_random_bytes(&group, sizeof(group));
		group = prandom_u32();
		parent_group = (unsigned)group % ngroups;
		for (i = 0; i < ngroups; i++) {
		group = (parent_group + i) % ngroups;

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