path: root/drivers/md
diff options
authorMichael Lass <bevan@bi-co.net>2019-05-21 21:58:07 +0200
committerMike Snitzer <snitzer@redhat.com>2019-05-21 19:15:20 -0400
commit51b86f9a8d1c4bb4e3862ee4b4c5f46072f7520d (patch)
tree3a37a21670c6d37acacda2de65022d4671dd35d6 /drivers/md
parent8454fca4f53bbe5e0a71613192674c8ce5c52318 (diff)
dm: make sure to obey max_io_len_target_boundary
Commit 61697a6abd24 ("dm: eliminate 'split_discard_bios' flag from DM target interface") incorrectly removed code from __send_changing_extent_only() that is required to impose a per-target IO boundary on IO that exceeds max_io_len_target_boundary(). Otherwise "special" IO (e.g. DISCARD, WRITE SAME, WRITE ZEROES) can write beyond where allowed. Fix this by restoring the max_io_len_target_boundary() limit in __send_changing_extent_only() Fixes: 61697a6abd24 ("dm: eliminate 'split_discard_bios' flag from DM target interface") Cc: stable@vger.kernel.org # 5.1+ Signed-off-by: Michael Lass <bevan@bi-co.net> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 1fb1333fefec..997385c1ca54 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1469,7 +1469,7 @@ static unsigned get_num_write_zeroes_bios(struct dm_target *ti)
static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti,
unsigned num_bios)
- unsigned len = ci->sector_count;
+ unsigned len;
* Even though the device advertised support for this type of
@@ -1480,6 +1480,8 @@ static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *
if (!num_bios)
+ len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti));
__send_duplicate_bios(ci, ti, num_bios, &len);
ci->sector += len;