From 4ed319c6ac08e9a28fca7ac188181ac122f4de84 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 5 Apr 2019 15:26:39 -0400 Subject: [PATCH] dm integrity: fix deadlock with overlapping I/O dm-integrity will deadlock if overlapping I/O is issued to it, the bug was introduced by commit 724376a04d1a ("dm integrity: implement fair range locks"). Users rarely use overlapping I/O so this bug went undetected until now. Fix this bug by correcting, likely cut-n-paste, typos in ranges_overlap() and also remove a flawed ranges_overlap() check in remove_range_unlocked(). This condition could leave unprocessed bios hanging on wait_list forever. Cc: stable@vger.kernel.org # v4.19+ Fixes: 724376a04d1a ("dm integrity: implement fair range locks") Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer --- drivers/md/dm-integrity.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 94b865c5ce71..7c678f50aaa3 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -913,7 +913,7 @@ static void copy_from_journal(struct dm_integrity_c *ic, unsigned section, unsig static bool ranges_overlap(struct dm_integrity_range *range1, struct dm_integrity_range *range2) { return range1->logical_sector < range2->logical_sector + range2->n_sectors && - range2->logical_sector + range2->n_sectors > range2->logical_sector; + range1->logical_sector + range1->n_sectors > range2->logical_sector; } static bool add_new_range(struct dm_integrity_c *ic, struct dm_integrity_range *new_range, bool check_waiting) @@ -959,8 +959,6 @@ static void remove_range_unlocked(struct dm_integrity_c *ic, struct dm_integrity struct dm_integrity_range *last_range = list_first_entry(&ic->wait_list, struct dm_integrity_range, wait_entry); struct task_struct *last_range_task; - if (!ranges_overlap(range, last_range)) - break; last_range_task = last_range->task; list_del(&last_range->wait_entry); if (!add_new_range(ic, last_range, false)) {