ieee80211_handle_wake_tx_queue must not run concurrent multiple times.
It calls ieee80211_txq_schedule_start() and the drivers migrated to iTXQ
do not expect overlapping drv_tx() calls.
This fixes 'c850e31f79f0 ("wifi: mac80211: add internal handler for
wake_tx_queue")', which introduced ieee80211_handle_wake_tx_queue.
Drivers started to use it with 'a790cc3a4fad ("wifi: mac80211: add
wake_tx_queue callback to drivers")'.
But only after fixing an independent bug with
'4444bc2116ae ("wifi: mac80211: Proper mark iTXQs for resumption")'
problematic concurrent calls really happened and exposed the initial
issue.
Fixes: c850e31f79f0 ("wifi: mac80211: add internal handler for wake_tx_queue")
Reported-by: Thomas Mann <rauchwolke(a)gmx.net>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217119
Link: https://lore.kernel.org/r/b8efebc6-4399-d0b8-b2a0-66843314616b@leemhuis.inf…
Link: https://lore.kernel.org/r/b7445607128a6b9ed7c17fcdcf3679bfaf4aaea.camel@sip…>
CC: <stable(a)vger.kernel.org>
Signed-off-by: Alexander Wetzel <alexander(a)wetzel-home.de>
---
@Thomas
Would be good when you can test that patch again.
But it would be really strange if it's not working, too...
@Johannes
Based on your last mail you prefer to hard serialize it and not use a
spin lock per AC. So I kept that part from the first patch.
Alexander
---
net/mac80211/ieee80211_i.h | 3 +++
net/mac80211/util.c | 3 +++
2 files changed, 6 insertions(+)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index ecc232eb1ee8..e082582e0aa2 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1284,6 +1284,9 @@ struct ieee80211_local {
struct list_head active_txqs[IEEE80211_NUM_ACS];
u16 schedule_round[IEEE80211_NUM_ACS];
+ /* serializes ieee80211_handle_wake_tx_queue */
+ spinlock_t handle_wake_tx_queue_lock;
+
u16 airtime_flags;
u32 aql_txq_limit_low[IEEE80211_NUM_ACS];
u32 aql_txq_limit_high[IEEE80211_NUM_ACS];
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 1a28fe5cb614..3aceb3b731bf 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -314,6 +314,8 @@ void ieee80211_handle_wake_tx_queue(struct ieee80211_hw *hw,
struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);
struct ieee80211_txq *queue;
+ spin_lock(&local->handle_wake_tx_queue_lock);
+
/* Use ieee80211_next_txq() for airtime fairness accounting */
ieee80211_txq_schedule_start(hw, txq->ac);
while ((queue = ieee80211_next_txq(hw, txq->ac))) {
@@ -321,6 +323,7 @@ void ieee80211_handle_wake_tx_queue(struct ieee80211_hw *hw,
ieee80211_return_txq(hw, queue, false);
}
ieee80211_txq_schedule_end(hw, txq->ac);
+ spin_unlock(&local->handle_wake_tx_queue_lock);
}
EXPORT_SYMBOL(ieee80211_handle_wake_tx_queue);
--
2.39.2
From: Eric Biggers <ebiggers(a)google.com>
Once all I/O using a blk_crypto_key has completed, filesystems can call
blk_crypto_evict_key(). However, the block layer currently doesn't call
blk_crypto_put_keyslot() until the request is being freed, which happens
after upper layers have been told (via bio_endio()) the I/O has
completed. This causes a race condition where blk_crypto_evict_key()
can see 'slot_refs != 0' without there being an actual bug.
This makes __blk_crypto_evict_key() hit the
'WARN_ON_ONCE(atomic_read(&slot->slot_refs) != 0)' and return without
doing anything, eventually causing a use-after-free in
blk_crypto_reprogram_all_keys(). (This is a very rare bug and has only
been seen when per-file keys are being used with fscrypt.)
There are two options to fix this: either release the keyslot before
bio_endio() is called on the request's last bio, or make
__blk_crypto_evict_key() ignore slot_refs. Let's go with the first
solution, since it preserves the ability to report bugs (via
WARN_ON_ONCE) where a key is evicted while still in-use.
Fixes: a892c8d52c02 ("block: Inline encryption support for blk-mq")
Cc: stable(a)vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers(a)google.com>
---
block/blk-crypto-internal.h | 25 +++++++++++++++++++++----
block/blk-crypto.c | 24 ++++++++++++------------
block/blk-merge.c | 2 ++
block/blk-mq.c | 15 ++++++++++++++-
4 files changed, 49 insertions(+), 17 deletions(-)
diff --git a/block/blk-crypto-internal.h b/block/blk-crypto-internal.h
index a8cdaf26851e..4f1de2495f0c 100644
--- a/block/blk-crypto-internal.h
+++ b/block/blk-crypto-internal.h
@@ -65,6 +65,11 @@ static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
return rq->crypt_ctx;
}
+static inline bool blk_crypto_rq_has_keyslot(struct request *rq)
+{
+ return rq->crypt_keyslot;
+}
+
blk_status_t blk_crypto_get_keyslot(struct blk_crypto_profile *profile,
const struct blk_crypto_key *key,
struct blk_crypto_keyslot **slot_ptr);
@@ -119,6 +124,11 @@ static inline bool blk_crypto_rq_is_encrypted(struct request *rq)
return false;
}
+static inline bool blk_crypto_rq_has_keyslot(struct request *rq)
+{
+ return false;
+}
+
#endif /* CONFIG_BLK_INLINE_ENCRYPTION */
void __bio_crypt_advance(struct bio *bio, unsigned int bytes);
@@ -153,14 +163,21 @@ static inline bool blk_crypto_bio_prep(struct bio **bio_ptr)
return true;
}
-blk_status_t __blk_crypto_init_request(struct request *rq);
-static inline blk_status_t blk_crypto_init_request(struct request *rq)
+blk_status_t __blk_crypto_rq_get_keyslot(struct request *rq);
+static inline blk_status_t blk_crypto_rq_get_keyslot(struct request *rq)
{
if (blk_crypto_rq_is_encrypted(rq))
- return __blk_crypto_init_request(rq);
+ return __blk_crypto_rq_get_keyslot(rq);
return BLK_STS_OK;
}
+void __blk_crypto_rq_put_keyslot(struct request *rq);
+static inline void blk_crypto_rq_put_keyslot(struct request *rq)
+{
+ if (blk_crypto_rq_has_keyslot(rq))
+ __blk_crypto_rq_put_keyslot(rq);
+}
+
void __blk_crypto_free_request(struct request *rq);
static inline void blk_crypto_free_request(struct request *rq)
{
@@ -199,7 +216,7 @@ static inline blk_status_t blk_crypto_insert_cloned_request(struct request *rq)
{
if (blk_crypto_rq_is_encrypted(rq))
- return blk_crypto_init_request(rq);
+ return blk_crypto_rq_get_keyslot(rq);
return BLK_STS_OK;
}
diff --git a/block/blk-crypto.c b/block/blk-crypto.c
index 45378586151f..d0c7feb447e9 100644
--- a/block/blk-crypto.c
+++ b/block/blk-crypto.c
@@ -224,27 +224,27 @@ static bool bio_crypt_check_alignment(struct bio *bio)
return true;
}
-blk_status_t __blk_crypto_init_request(struct request *rq)
+blk_status_t __blk_crypto_rq_get_keyslot(struct request *rq)
{
return blk_crypto_get_keyslot(rq->q->crypto_profile,
rq->crypt_ctx->bc_key,
&rq->crypt_keyslot);
}
-/**
- * __blk_crypto_free_request - Uninitialize the crypto fields of a request.
- *
- * @rq: The request whose crypto fields to uninitialize.
- *
- * Completely uninitializes the crypto fields of a request. If a keyslot has
- * been programmed into some inline encryption hardware, that keyslot is
- * released. The rq->crypt_ctx is also freed.
- */
-void __blk_crypto_free_request(struct request *rq)
+void __blk_crypto_rq_put_keyslot(struct request *rq)
{
blk_crypto_put_keyslot(rq->crypt_keyslot);
+ rq->crypt_keyslot = NULL;
+}
+
+void __blk_crypto_free_request(struct request *rq)
+{
+ /* The keyslot, if one was needed, should have been released earlier. */
+ if (WARN_ON_ONCE(rq->crypt_keyslot))
+ __blk_crypto_rq_put_keyslot(rq);
+
mempool_free(rq->crypt_ctx, bio_crypt_ctx_pool);
- blk_crypto_rq_set_defaults(rq);
+ rq->crypt_ctx = NULL;
}
/**
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 6460abdb2426..65e75efa9bd3 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -867,6 +867,8 @@ static struct request *attempt_merge(struct request_queue *q,
if (!blk_discard_mergable(req))
elv_merge_requests(q, req, next);
+ blk_crypto_rq_put_keyslot(next);
+
/*
* 'next' is going away, so update stats accordingly
*/
diff --git a/block/blk-mq.c b/block/blk-mq.c
index d0cb2ef18fe2..49825538d932 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -840,6 +840,12 @@ static void blk_complete_request(struct request *req)
req->q->integrity.profile->complete_fn(req, total_bytes);
#endif
+ /*
+ * Upper layers may call blk_crypto_evict_key() anytime after the last
+ * bio_endio(). Therefore, the keyslot must be released before that.
+ */
+ blk_crypto_rq_put_keyslot(req);
+
blk_account_io_completion(req, total_bytes);
do {
@@ -905,6 +911,13 @@ bool blk_update_request(struct request *req, blk_status_t error,
req->q->integrity.profile->complete_fn(req, nr_bytes);
#endif
+ /*
+ * Upper layers may call blk_crypto_evict_key() anytime after the last
+ * bio_endio(). Therefore, the keyslot must be released before that.
+ */
+ if (blk_crypto_rq_has_keyslot(req) && nr_bytes >= blk_rq_bytes(req))
+ __blk_crypto_rq_put_keyslot(req);
+
if (unlikely(error && !blk_rq_is_passthrough(req) &&
!(req->rq_flags & RQF_QUIET)) &&
!test_bit(GD_DEAD, &req->q->disk->state)) {
@@ -2967,7 +2980,7 @@ void blk_mq_submit_bio(struct bio *bio)
blk_mq_bio_to_request(rq, bio, nr_segs);
- ret = blk_crypto_init_request(rq);
+ ret = blk_crypto_rq_get_keyslot(rq);
if (ret != BLK_STS_OK) {
bio->bi_status = ret;
bio_endio(bio);
--
2.39.2
Hi Greg
6.2.7-rc1
compiles [1], boots and runs here on x86_64
(Intel i5-11400, Fedora 38 Beta)
Thanks
Tested-by: Ronald Warsow <rwarsow(a)gmx.de>
[1]
compiles *not* without warnings since compiler version change from
Fedora 37 => Fedora 38 *Beta*
It's *not* a regression from kernel 6.2.6 => 6.2.7-rc1 !
cause I'm no developer I can't decide what it is: code or compiler.
anyway I I filled a Red Hat bug report:
https://bugzilla.redhat.com/show_bug.cgi?id=2178317
and place the warnings here in case it is coding.
if so, please let me know, so I could suggest to close the bug report !
compilers
=========
F38: gcc version 13.0.1 20230310 (Red Hat 13.0.1-0) (GCC)
F37: gcc-12.2.1-4.fc37
output compiling 6.2.7-rc1
==========================
CC fs/f2fs/file.o
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_disk_total’ at
fs/btrfs/sysfs.c:836:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -35 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_bytes_may_use’ at
fs/btrfs/sysfs.c:832:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -44 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_bytes_readonly’ at
fs/btrfs/sysfs.c:833:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -43 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_bytes_zone_unusable’ at
fs/btrfs/sysfs.c:834:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -41 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_disk_used’ at
fs/btrfs/sysfs.c:835:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -36 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_flags’ at fs/btrfs/sysfs.c:827:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -34 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_total_bytes’ at
fs/btrfs/sysfs.c:828:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -48 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_bytes_used’ at
fs/btrfs/sysfs.c:829:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -47 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_bytes_pinned’ at
fs/btrfs/sysfs.c:830:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -46 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
In function ‘btrfs_show_u64’,
inlined from ‘btrfs_space_info_show_bytes_reserved’ at
fs/btrfs/sysfs.c:831:1:
fs/btrfs/sysfs.c:636:13: warning: array subscript -45 is outside array
bounds of ‘struct kobject[144115188075855871]’ [-Warray-bounds=]
636 | val = *value_ptr;
| ~~~~^~~~~~~~~~~~
...
CC drivers/usb/core/devio.o
fs/super.c: In function ‘alloc_super’:
fs/super.c:234:21: warning: array subscript 2 is outside the bounds of
an interior zero-length array ‘struct lock_class_key[3]’
[-Wzero-length-bounds]
234 | if (__percpu_init_rwsem(&s->s_writers.rw_sem[i],
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
235 | sb_writers_name[i],
| ~~~~~~~~~~~~~~~~~~~
236 | &type->s_writers_key[i]))
| ~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ./include/linux/highmem.h:5,
from ./include/linux/bvec.h:10,
from ./include/linux/blk_types.h:10,
from ./include/linux/blkdev.h:9,
from fs/super.c:26:
./include/linux/fs.h:2549:31: note: while referencing ‘s_writers_key’
2549 | struct lock_class_key s_writers_key[SB_FREEZE_LEVELS];
| ^~~~~~~~~~~~
...