The patch below does not apply to the 6.2-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.2.y git checkout FETCH_HEAD git cherry-pick -x f7b58a69fad9d2c4c90cab0247811155dd0d48e7 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023040332-dodgy-chamomile-54f5@gregkh' --subject-prefix 'PATCH 6.2.y' HEAD^..

Possible dependencies:

f7b58a69fad9 ("dm: fix improper splitting for abnormal bios") 86a3238c7b9b ("dm: change "unsigned" to "unsigned int"") 7533afa1d27b ("dm: send just one event on resize, not two") 5cd6d1d53a1f ("dm integrity: Remove bi_sector that's only used by commented debug code") 22c40e134c4c ("dm cache: Add some documentation to dm-cache-background-tracker.h")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f7b58a69fad9d2c4c90cab0247811155dd0d48e7 Mon Sep 17 00:00:00 2001 From: Mike Snitzer snitzer@kernel.org Date: Thu, 30 Mar 2023 14:56:38 -0400 Subject: [PATCH] dm: fix improper splitting for abnormal bios

"Abnormal" bios include discards, write zeroes and secure erase. By no longer passing the calculated 'len' pointer, commit 7dd06a2548b2 ("dm: allow dm_accept_partial_bio() for dm_io without duplicate bios") took a senseless approach to disallowing dm_accept_partial_bio() from working for duplicate bios processed using __send_duplicate_bios().

It inadvertently and incorrectly stopped the use of 'len' when initializing a target's io (in alloc_tio). As such the resulting tio could address more area of a device than it should.

For example, when discarding an entire DM striped device with the following DM table: vg-lvol0: 0 159744 striped 2 128 7:0 2048 7:1 2048 vg-lvol0: 159744 45056 striped 2 128 7:2 2048 7:3 2048

Before this fix:

device-mapper: striped: target_stripe=0, bdev=7:0, start=2048 len=102400 blkdiscard: attempt to access beyond end of device loop0: rw=2051, sector=2048, nr_sectors = 102400 limit=81920

device-mapper: striped: target_stripe=1, bdev=7:1, start=2048 len=102400 blkdiscard: attempt to access beyond end of device loop1: rw=2051, sector=2048, nr_sectors = 102400 limit=81920

After this fix;

device-mapper: striped: target_stripe=0, bdev=7:0, start=2048 len=79872 device-mapper: striped: target_stripe=1, bdev=7:1, start=2048 len=79872

Fixes: 7dd06a2548b2 ("dm: allow dm_accept_partial_bio() for dm_io without duplicate bios") Cc: stable@vger.kernel.org Reported-by: Orange Kao orange@aiven.io Signed-off-by: Mike Snitzer snitzer@kernel.org

diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 2d0f934ba6e6..e67a2757c53e 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1467,7 +1467,8 @@ static void setup_split_accounting(struct clone_info *ci, unsigned int len) }

static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, - struct dm_target *ti, unsigned int num_bios) + struct dm_target *ti, unsigned int num_bios, + unsigned *len) { struct bio *bio; int try; @@ -1478,7 +1479,7 @@ static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, if (try) mutex_lock(&ci->io->md->table_devices_lock); for (bio_nr = 0; bio_nr < num_bios; bio_nr++) { - bio = alloc_tio(ci, ti, bio_nr, NULL, + bio = alloc_tio(ci, ti, bio_nr, len, try ? GFP_NOIO : GFP_NOWAIT); if (!bio) break; @@ -1514,7 +1515,7 @@ static int __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, break; default: /* dm_accept_partial_bio() is not supported with shared tio->len_ptr */ - alloc_multiple_bios(&blist, ci, ti, num_bios); + alloc_multiple_bios(&blist, ci, ti, num_bios, len); while ((clone = bio_list_pop(&blist))) { dm_tio_set_flag(clone_to_tio(clone), DM_TIO_IS_DUPLICATE_BIO); __map_bio(clone);