This is a note to let you know that I've just added the patch titled
dm integrity: fix deadlock with overlapping I/O
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dm-integrity-fix-deadlock-with-overlapping-i-o.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4ed319c6ac08e9a28fca7ac188181ac122f4de84 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Date: Fri, 5 Apr 2019 15:26:39 -0400
Subject: dm integrity: fix deadlock with overlapping I/O
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx # v4.19+
Fixes: 724376a04d1a ("dm integrity: implement fair range locks")
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -908,7 +908,7 @@ 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)
@@ -954,8 +954,6 @@ 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)) {
Patches currently in stable-queue which might be from mpatocka@xxxxxxxxxx are
queue-4.19/dm-integrity-change-memcmp-to-strncmp-in-dm_integrity_ctr.patch
queue-4.19/dm-integrity-fix-deadlock-with-overlapping-i-o.patch
queue-4.19/dm-revert-8f50e358153d-dm-limit-the-max-bio-size-as-bio_max_pages-page_size.patch
