From: Takashi Iwai <tiwai(a)suse.de>
Subject: resource: fix integer overflow at reallocation
We've got a bug report indicating a kernel panic at booting on an x86-32
system, and it turned out to be the invalid PCI resource assigned after
reallocation. __find_resource() first aligns the resource start address
and resets the end address with start+size-1 accordingly, then checks
whether it's contained. Here the end address may overflow the integer,
although resource_contains() still returns true because the function
validates only start and end address. So this ends up with returning an
invalid resource (start > end).
There was already an attempt to cover such a problem in the commit
47ea91b4052d ("Resource: fix wrong resource window calculation"), but this
case is an overseen one.
This patch adds the validity check of the newly calculated resource for
avoiding the integer overflow problem.
Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=1086739
Link: http://lkml.kernel.org/r/s5hpo37d5l8.wl-tiwai@suse.de
Fixes: 23c570a67448 ("resource: ability to resize an allocated resource")
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Reported-by: Michael Henders <hendersm(a)shaw.ca>
Tested-by: Michael Henders <hendersm(a)shaw.ca>
Reviewed-by: Andrew Morton <akpm(a)linux-foundation.org>
Cc: Ram Pai <linuxram(a)us.ibm.com>
Cc: Bjorn Helgaas <bhelgaas(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
kernel/resource.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff -puN kernel/resource.c~resource-fix-integer-overflow-at-reallocation-v1 kernel/resource.c
--- a/kernel/resource.c~resource-fix-integer-overflow-at-reallocation-v1
+++ a/kernel/resource.c
@@ -651,7 +651,8 @@ static int __find_resource(struct resour
alloc.start = constraint->alignf(constraint->alignf_data, &avail,
size, constraint->align);
alloc.end = alloc.start + size - 1;
- if (resource_contains(&avail, &alloc)) {
+ if (alloc.start <= alloc.end &&
+ resource_contains(&avail, &alloc)) {
new->start = alloc.start;
new->end = alloc.end;
return 0;
_
The patch titled
Subject: mm-gup_benchmark-handle-gup-failures-fix
has been removed from the -mm tree. Its filename was
mm-gup_benchmark-handle-gup-failures-fix.patch
This patch was dropped because it was folded into mm-gup_benchmark-handle-gup-failures.patch
------------------------------------------------------
From: Andrew Morton <akpm(a)linux-foundation.org>
Subject: mm-gup_benchmark-handle-gup-failures-fix
Cc: Huang Ying <ying.huang(a)intel.com>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: "Michael S. Tsirkin" <mst(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: <stable(a)vger.kernel.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Thorsten Leemhuis <regressions(a)leemhuis.info>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/gup_benchmark.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff -puN mm/gup_benchmark.c~mm-gup_benchmark-handle-gup-failures-fix mm/gup_benchmark.c
--- a/mm/gup_benchmark.c~mm-gup_benchmark-handle-gup-failures-fix
+++ a/mm/gup_benchmark.c
@@ -41,8 +41,9 @@ static int __gup_benchmark_ioctl(unsigne
}
nr = get_user_pages_fast(addr, nr, gup->flags & 1, pages + i);
- if (nr > 0)
- i += nr;
+ if (nr <= 0)
+ break;
+ i += nr;
}
end_time = ktime_get();
_
Patches currently in -mm which might be from akpm(a)linux-foundation.org are
i-need-old-gcc.patch
mm-gup_benchmark-handle-gup-failures.patch
mm-pagemap-fix-swap-offset-value-for-pmd-migration-entry-fix.patch
writeback-safer-lock-nesting-fix.patch
arm-arch-arm-include-asm-pageh-needs-personalityh.patch
ocfs2-without-quota-support-try-to-avoid-calling-quota-recovery-checkpatch-fixes.patch
mm.patch
list_lru-prefetch-neighboring-list-entries-before-acquiring-lock-fix.patch
mm-oom-cgroup-aware-oom-killer-fix.patch
mm-oom-docs-describe-the-cgroup-aware-oom-killer-fix-2-fix.patch
linux-next-rejects.patch
fs-fsnotify-account-fsnotify-metadata-to-kmemcg-fix.patch
kernel-forkc-export-kernel_thread-to-modules.patch
slab-leaks3-default-y.patch
The patch titled
Subject: autofs: mount point create should honour passed in mode
has been added to the -mm tree. Its filename is
autofs-mount-point-create-should-honour-passed-in-mode.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/autofs-mount-point-create-should-h…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/autofs-mount-point-create-should-h…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Ian Kent <raven(a)themaw.net>
Subject: autofs: mount point create should honour passed in mode
The autofs file system mkdir inode operation blindly sets the created
directory mode to S_IFDIR | 0555, ingoring the passed in mode, which can
cause selinux dac_override denials.
But the function also checks if the caller is the daemon (as no-one else
should be able to do anything here) so there's no point in not honouring
the passed in mode, allowing the daemon to set appropriate mode when
required.
Link: http://lkml.kernel.org/r/152361593601.8051.14014139124905996173.stgit@pluto…
Signed-off-by: Ian Kent <raven(a)themaw.net>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
fs/autofs4/root.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN fs/autofs4/root.c~autofs-mount-point-create-should-honour-passed-in-mode fs/autofs4/root.c
--- a/fs/autofs4/root.c~autofs-mount-point-create-should-honour-passed-in-mode
+++ a/fs/autofs4/root.c
@@ -749,7 +749,7 @@ static int autofs4_dir_mkdir(struct inod
autofs4_del_active(dentry);
- inode = autofs4_get_inode(dir->i_sb, S_IFDIR | 0555);
+ inode = autofs4_get_inode(dir->i_sb, S_IFDIR | mode);
if (!inode)
return -ENOMEM;
d_add(dentry, inode);
_
Patches currently in -mm which might be from raven(a)themaw.net are
autofs-mount-point-create-should-honour-passed-in-mode.patch
From: Josef Bacik <jbacik(a)fb.com>
This fixes a use after free bug, we need to do the del_gendisk after we
cleanup the queue on the device.
Fixes: c6a4759ea0c9 ("nbd: add device refcounting")
cc: stable(a)vger.kernel.org
Signed-off-by: Josef Bacik <jbacik(a)fb.com>
---
drivers/block/nbd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 86258b00a1d4..e33da3e6aa20 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -174,8 +174,8 @@ static void nbd_dev_remove(struct nbd_device *nbd)
{
struct gendisk *disk = nbd->disk;
if (disk) {
- del_gendisk(disk);
blk_cleanup_queue(disk->queue);
+ del_gendisk(disk);
blk_mq_free_tag_set(&nbd->tag_set);
disk->private_data = NULL;
put_disk(disk);
--
2.14.3
The normal request completion can be done before or during handling
BLK_EH_RESET_TIMER, and this race may cause the request to never
be completed since driver's .timeout() may always return
BLK_EH_RESET_TIMER.
This issue can't be fixed completely by driver, since the normal
completion can be done between returning .timeout() and handing
BLK_EH_RESET_TIMER.
This patch fixes this race by introducing rq state of MQ_RQ_COMPLETE_IN_RESET,
and reading/writing rq's state by holding queue lock, which can be
per-request actually, but just not necessary to introduce one lock for
so unusual event.
Cc: Bart Van Assche <bart.vanassche(a)wdc.com>
Cc: Tejun Heo <tj(a)kernel.org>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Ming Lei <ming.lei(a)redhat.com>
Cc: Sagi Grimberg <sagi(a)grimberg.me>
Cc: Israel Rukshin <israelr(a)mellanox.com>,
Cc: Max Gurtovoy <maxg(a)mellanox.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Ming Lei <ming.lei(a)redhat.com>
---
This is another way to fix this long-time issue, and turns out this
solution is much simpler.
block/blk-mq.c | 44 +++++++++++++++++++++++++++++++++++++++-----
block/blk-mq.h | 1 +
2 files changed, 40 insertions(+), 5 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 0dc9e341c2a7..12e8850e3905 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -630,10 +630,27 @@ void blk_mq_complete_request(struct request *rq)
* However, that would complicate paths which want to synchronize
* against us. Let stay in sync with the issue path so that
* hctx_lock() covers both issue and completion paths.
+ *
+ * Cover complete vs BLK_EH_RESET_TIMER race in slow path with
+ * helding queue lock.
*/
hctx_lock(hctx, &srcu_idx);
if (blk_mq_rq_aborted_gstate(rq) != rq->gstate)
__blk_mq_complete_request(rq);
+ else {
+ unsigned long flags;
+ bool need_complete = false;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (!blk_mq_rq_aborted_gstate(rq))
+ need_complete = true;
+ else
+ blk_mq_rq_update_state(rq, MQ_RQ_COMPLETE_IN_RESET);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ if (need_complete)
+ __blk_mq_complete_request(rq);
+ }
hctx_unlock(hctx, srcu_idx);
}
EXPORT_SYMBOL(blk_mq_complete_request);
@@ -814,24 +831,41 @@ static void blk_mq_rq_timed_out(struct request *req, bool reserved)
{
const struct blk_mq_ops *ops = req->q->mq_ops;
enum blk_eh_timer_return ret = BLK_EH_RESET_TIMER;
+ unsigned long flags;
req->rq_flags |= RQF_MQ_TIMEOUT_EXPIRED;
if (ops->timeout)
ret = ops->timeout(req, reserved);
+again:
switch (ret) {
case BLK_EH_HANDLED:
__blk_mq_complete_request(req);
break;
case BLK_EH_RESET_TIMER:
/*
- * As nothing prevents from completion happening while
- * ->aborted_gstate is set, this may lead to ignored
- * completions and further spurious timeouts.
+ * The normal completion may happen during handling the
+ * timeout, or even after returning from .timeout(), so
+ * once the request has been completed, we can't reset
+ * timer any more since this request may be handled as
+ * BLK_EH_RESET_TIMER in next timeout handling too, and
+ * it has to be completed in this situation.
+ *
+ * Holding the queue lock to cover read/write rq's
+ * aborted_gstate and normal state, so the race can be
+ * avoided completely.
*/
- blk_mq_rq_update_aborted_gstate(req, 0);
- blk_add_timer(req);
+ spin_lock_irqsave(req->q->queue_lock, flags);
+ if (blk_mq_rq_state(req) != MQ_RQ_COMPLETE_IN_RESET) {
+ blk_mq_rq_update_aborted_gstate(req, 0);
+ blk_add_timer(req);
+ } else {
+ blk_mq_rq_update_state(req, MQ_RQ_IN_FLIGHT);
+ ret = BLK_EH_HANDLED;
+ goto again;
+ }
+ spin_unlock_irqrestore(req->q->queue_lock, flags);
break;
case BLK_EH_NOT_HANDLED:
break;
diff --git a/block/blk-mq.h b/block/blk-mq.h
index 88c558f71819..6dc242fc785a 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -35,6 +35,7 @@ enum mq_rq_state {
MQ_RQ_IDLE = 0,
MQ_RQ_IN_FLIGHT = 1,
MQ_RQ_COMPLETE = 2,
+ MQ_RQ_COMPLETE_IN_RESET = 3,
MQ_RQ_STATE_BITS = 2,
MQ_RQ_STATE_MASK = (1 << MQ_RQ_STATE_BITS) - 1,
--
2.9.5