From f069c7ab6cfb07edf9e3dc2071928225587794f1 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 13 Dec 2021 14:33:25 -0800 Subject: 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: Kees Cook Signed-off-by: Mike Snitzer --- drivers/md/dm-integrity.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'drivers/md/dm-integrity.c') diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 7af242de3202..eb4b5e52bd6f 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -121,8 +121,10 @@ struct journal_entry { #define JOURNAL_MAC_SIZE (JOURNAL_MAC_PER_SECTOR * JOURNAL_BLOCK_SECTORS) struct journal_sector { - __u8 entries[JOURNAL_SECTOR_DATA - JOURNAL_MAC_PER_SECTOR]; - __u8 mac[JOURNAL_MAC_PER_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++) { -- cgit