Commit f069c7ab authored by Kees Cook's avatar Kees Cook Committed by Mike Snitzer
Browse files

dm integrity: Use struct_group() to zero struct journal_sector 



In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.

Add struct_group() to mark region of struct journal_sector that should be
initialized to zero.

Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent cba23ac1

drivers/md/dm-integrity.c

+6 −3
Original line number Diff line number Diff line
@@ -121,8 +121,10 @@ struct journal_entry { 
#define JOURNAL_MAC_SIZE		(JOURNAL_MAC_PER_SECTOR * JOURNAL_BLOCK_SECTORS)



struct journal_sector {

	struct_group(sectors,

		__u8 entries[JOURNAL_SECTOR_DATA - JOURNAL_MAC_PER_SECTOR];

		__u8 mac[JOURNAL_MAC_PER_SECTOR];

	);

	commit_id_t commit_id;

};
@@ -2870,7 +2872,8 @@ static void init_journal(struct dm_integrity_c *ic, unsigned start_section, 
		wraparound_section(ic, &i);

		for (j = 0; j < ic->journal_section_sectors; j++) {

			struct journal_sector *js = access_journal(ic, i, j);

			memset(&js->entries, 0, JOURNAL_SECTOR_DATA);

			BUILD_BUG_ON(sizeof(js->sectors) != JOURNAL_SECTOR_DATA);

			memset(&js->sectors, 0, sizeof(js->sectors));

			js->commit_id = dm_integrity_commit_id(ic, i, j, commit_seq);

		}

		for (j = 0; j < ic->journal_section_entries; j++) {