| From 4ed319c6ac08e9a28fca7ac188181ac122f4de84 Mon Sep 17 00:00:00 2001 |
| From: Mikulas Patocka <mpatocka@redhat.com> |
| Date: Fri, 5 Apr 2019 15:26:39 -0400 |
| Subject: dm integrity: fix deadlock with overlapping I/O |
| |
| From: Mikulas Patocka <mpatocka@redhat.com> |
| |
| commit 4ed319c6ac08e9a28fca7ac188181ac122f4de84 upstream. |
| |
| 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 <mpatocka@redhat.com> |
| Signed-off-by: Mike Snitzer <snitzer@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/md/dm-integrity.c | 4 +--- |
| 1 file changed, 1 insertion(+), 3 deletions(-) |
| |
| --- a/drivers/md/dm-integrity.c |
| +++ b/drivers/md/dm-integrity.c |
| @@ -913,7 +913,7 @@ static void copy_from_journal(struct dm_ |
| 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 |
| 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)) { |