[PATCH AUTOSEL 5.4 1/7] net: mac802154: Fix racy device stats updates by DEV_STATS_INC() and DEV_STATS_ADD()

[PATCH AUTOSEL 5.4 1/7] net: mac802154: Fix racy device stats updates by DEV_STATS_INC() and DEV_STATS_ADD()

[Sasha Levin]

From: Yunshui Jiang <jiangyunshui@kylinos.cn>

[ Upstream commit b8ec0dc3845f6c9089573cb5c2c4b05f7fc10728 ]

mac802154 devices update their dev->stats fields locklessly. Therefore
these counters should be updated atomically. Adopt SMP safe DEV_STATS_INC()
and DEV_STATS_ADD() to achieve this.

Signed-off-by: Yunshui Jiang <jiangyunshui@kylinos.cn>
Message-ID: <20240531080739.2608969-1-jiangyunshui@kylinos.cn>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/mac802154/tx.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c
index c829e4a753256..7cea95d0b78f9 100644
--- a/net/mac802154/tx.c
+++ b/net/mac802154/tx.c
@@ -34,8 +34,8 @@ void ieee802154_xmit_worker(struct work_struct *work)
 	if (res)
 		goto err_tx;
 
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += skb->len;
+	DEV_STATS_INC(dev, tx_packets);
+	DEV_STATS_ADD(dev, tx_bytes, skb->len);
 
 	ieee802154_xmit_complete(&local->hw, skb, false);
 
@@ -86,8 +86,8 @@ ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
 			goto err_tx;
 		}
 
-		dev->stats.tx_packets++;
-		dev->stats.tx_bytes += len;
+		DEV_STATS_INC(dev, tx_packets);
+		DEV_STATS_ADD(dev, tx_bytes, len);
 	} else {
 		local->tx_skb = skb;
 		queue_work(local->workqueue, &local->tx_work);
-- 
2.43.0

[PATCH AUTOSEL 5.4 2/7] powerpc/pseries: Whitelist dtl slub object for copying to userspace

[Sasha Levin]

From: Anjali K <anjalik@linux.ibm.com>

[ Upstream commit 1a14150e1656f7a332a943154fc486504db4d586 ]

Reading the dispatch trace log from /sys/kernel/debug/powerpc/dtl/cpu-*
results in a BUG() when the config CONFIG_HARDENED_USERCOPY is enabled as
shown below.

    kernel BUG at mm/usercopy.c:102!
    Oops: Exception in kernel mode, sig: 5 [#1]
    LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
    Modules linked in: xfs libcrc32c dm_service_time sd_mod t10_pi sg ibmvfc
    scsi_transport_fc ibmveth pseries_wdt dm_multipath dm_mirror dm_region_hash dm_log dm_mod fuse
    CPU: 27 PID: 1815 Comm: python3 Not tainted 6.10.0-rc3 #85
    Hardware name: IBM,9040-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_042) hv:phyp pSeries
    NIP:  c0000000005d23d4 LR: c0000000005d23d0 CTR: 00000000006ee6f8
    REGS: c000000120c078c0 TRAP: 0700   Not tainted  (6.10.0-rc3)
    MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 2828220f  XER: 0000000e
    CFAR: c0000000001fdc80 IRQMASK: 0
    [ ... GPRs omitted ... ]
    NIP [c0000000005d23d4] usercopy_abort+0x78/0xb0
    LR [c0000000005d23d0] usercopy_abort+0x74/0xb0
    Call Trace:
     usercopy_abort+0x74/0xb0 (unreliable)
     __check_heap_object+0xf8/0x120
     check_heap_object+0x218/0x240
     __check_object_size+0x84/0x1a4
     dtl_file_read+0x17c/0x2c4
     full_proxy_read+0x8c/0x110
     vfs_read+0xdc/0x3a0
     ksys_read+0x84/0x144
     system_call_exception+0x124/0x330
     system_call_vectored_common+0x15c/0x2ec
    --- interrupt: 3000 at 0x7fff81f3ab34

Commit 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0")
requires that only whitelisted areas in slab/slub objects can be copied to
userspace when usercopy hardening is enabled using CONFIG_HARDENED_USERCOPY.
Dtl contains hypervisor dispatch events which are expected to be read by
privileged users. Hence mark this safe for user access.
Specify useroffset=0 and usersize=DISPATCH_LOG_BYTES to whitelist the
entire object.

Co-developed-by: Vishal Chourasia <vishalc@linux.ibm.com>
Signed-off-by: Vishal Chourasia <vishalc@linux.ibm.com>
Signed-off-by: Anjali K <anjalik@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240614173844.746818-1-anjalik@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/platforms/pseries/setup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index d5abb25865e36..bc1a4e024529b 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -305,8 +305,8 @@ static int alloc_dispatch_log_kmem_cache(void)
 {
 	void (*ctor)(void *) = get_dtl_cache_ctor();
 
-	dtl_cache = kmem_cache_create("dtl", DISPATCH_LOG_BYTES,
-						DISPATCH_LOG_BYTES, 0, ctor);
+	dtl_cache = kmem_cache_create_usercopy("dtl", DISPATCH_LOG_BYTES,
+						DISPATCH_LOG_BYTES, 0, 0, DISPATCH_LOG_BYTES, ctor);
 	if (!dtl_cache) {
 		pr_warn("Failed to create dispatch trace log buffer cache\n");
 		pr_warn("Stolen time statistics will be unreliable\n");
-- 
2.43.0

[PATCH AUTOSEL 5.4 3/7] powerpc/eeh: avoid possible crash when edev->pdev changes

[Sasha Levin]

From: Ganesh Goudar <ganeshgr@linux.ibm.com>

[ Upstream commit a1216e62d039bf63a539bbe718536ec789a853dd ]

If a PCI device is removed during eeh_pe_report_edev(), edev->pdev
will change and can cause a crash, hold the PCI rescan/remove lock
while taking a copy of edev->pdev->bus.

Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240617140240.580453-1-ganeshgr@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/kernel/eeh_pe.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index 177852e39a253..4b6b1846e4d23 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -922,6 +922,7 @@ struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
 {
 	struct eeh_dev *edev;
 	struct pci_dev *pdev;
+	struct pci_bus *bus = NULL;
 
 	if (pe->type & EEH_PE_PHB)
 		return pe->phb->bus;
@@ -932,9 +933,11 @@ struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
 
 	/* Retrieve the parent PCI bus of first (top) PCI device */
 	edev = list_first_entry_or_null(&pe->edevs, struct eeh_dev, entry);
+	pci_lock_rescan_remove();
 	pdev = eeh_dev_to_pci_dev(edev);
 	if (pdev)
-		return pdev->bus;
+		bus = pdev->bus;
+	pci_unlock_rescan_remove();
 
-	return NULL;
+	return bus;
 }
-- 
2.43.0

[PATCH AUTOSEL 5.4 4/7] scsi: libsas: Fix exp-attached device scan after probe failure scanned in again after probe failed

[Sasha Levin]

From: Xingui Yang <yangxingui@huawei.com>

[ Upstream commit ab2068a6fb84751836a84c26ca72b3beb349619d ]

The expander phy will be treated as broadcast flutter in the next
revalidation after the exp-attached end device probe failed, as follows:

[78779.654026] sas: broadcast received: 0
[78779.654037] sas: REVALIDATING DOMAIN on port 0, pid:10
[78779.654680] sas: ex 500e004aaaaaaa1f phy05 change count has changed
[78779.662977] sas: ex 500e004aaaaaaa1f phy05 originated BROADCAST(CHANGE)
[78779.662986] sas: ex 500e004aaaaaaa1f phy05 new device attached
[78779.663079] sas: ex 500e004aaaaaaa1f phy05:U:8 attached: 500e004aaaaaaa05 (stp)
[78779.693542] hisi_sas_v3_hw 0000:b4:02.0: dev[16:5] found
[78779.701155] sas: done REVALIDATING DOMAIN on port 0, pid:10, res 0x0
[78779.707864] sas: Enter sas_scsi_recover_host busy: 0 failed: 0
...
[78835.161307] sas: --- Exit sas_scsi_recover_host: busy: 0 failed: 0 tries: 1
[78835.171344] sas: sas_probe_sata: for exp-attached device 500e004aaaaaaa05 returned -19
[78835.180879] hisi_sas_v3_hw 0000:b4:02.0: dev[16:5] is gone
[78835.187487] sas: broadcast received: 0
[78835.187504] sas: REVALIDATING DOMAIN on port 0, pid:10
[78835.188263] sas: ex 500e004aaaaaaa1f phy05 change count has changed
[78835.195870] sas: ex 500e004aaaaaaa1f phy05 originated BROADCAST(CHANGE)
[78835.195875] sas: ex 500e004aaaaaaa1f rediscovering phy05
[78835.196022] sas: ex 500e004aaaaaaa1f phy05:U:A attached: 500e004aaaaaaa05 (stp)
[78835.196026] sas: ex 500e004aaaaaaa1f phy05 broadcast flutter
[78835.197615] sas: done REVALIDATING DOMAIN on port 0, pid:10, res 0x0

The cause of the problem is that the related ex_phy's attached_sas_addr was
not cleared after the end device probe failed, so reset it.

Signed-off-by: Xingui Yang <yangxingui@huawei.com>
Link: https://lore.kernel.org/r/20240619091742.25465-1-yangxingui@huawei.com
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/libsas/sas_internal.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/scsi/libsas/sas_internal.h b/drivers/scsi/libsas/sas_internal.h
index 01f1738ce6dff..3fb8a64f571d5 100644
--- a/drivers/scsi/libsas/sas_internal.h
+++ b/drivers/scsi/libsas/sas_internal.h
@@ -111,6 +111,20 @@ static inline void sas_fail_probe(struct domain_device *dev, const char *func, i
 		func, dev->parent ? "exp-attached" :
 		"direct-attached",
 		SAS_ADDR(dev->sas_addr), err);
+
+	/*
+	 * If the device probe failed, the expander phy attached address
+	 * needs to be reset so that the phy will not be treated as flutter
+	 * in the next revalidation
+	 */
+	if (dev->parent && !dev_is_expander(dev->dev_type)) {
+		struct sas_phy *phy = dev->phy;
+		struct domain_device *parent = dev->parent;
+		struct ex_phy *ex_phy = &parent->ex_dev.ex_phy[phy->number];
+
+		memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
+	}
+
 	sas_unregister_dev(dev->port, dev);
 }
 
-- 
2.43.0

[PATCH AUTOSEL 5.4 5/7] Bluetooth: hci_core: cancel all works upon hci_unregister_dev()

[Sasha Levin]

From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

[ Upstream commit 0d151a103775dd9645c78c97f77d6e2a5298d913 ]

syzbot is reporting that calling hci_release_dev() from hci_error_reset()
due to hci_dev_put() from hci_error_reset() can cause deadlock at
destroy_workqueue(), for hci_error_reset() is called from
hdev->req_workqueue which destroy_workqueue() needs to flush.

We need to make sure that hdev->{rx_work,cmd_work,tx_work} which are
queued into hdev->workqueue and hdev->{power_on,error_reset} which are
queued into hdev->req_workqueue are no longer running by the moment

       destroy_workqueue(hdev->workqueue);
       destroy_workqueue(hdev->req_workqueue);

are called from hci_release_dev().

Call cancel_work_sync() on these work items from hci_unregister_dev()
as soon as hdev->list is removed from hci_dev_list.

Reported-by: syzbot <syzbot+da0a9c9721e36db712e8@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=da0a9c9721e36db712e8
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/bluetooth/hci_core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index c60204b639ab7..71a7e42097cc0 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3412,7 +3412,11 @@ void hci_unregister_dev(struct hci_dev *hdev)
 	list_del(&hdev->list);
 	write_unlock(&hci_dev_list_lock);
 
+	cancel_work_sync(&hdev->rx_work);
+	cancel_work_sync(&hdev->cmd_work);
+	cancel_work_sync(&hdev->tx_work);
 	cancel_work_sync(&hdev->power_on);
+	cancel_work_sync(&hdev->error_reset);
 
 	hci_dev_do_close(hdev);
 
-- 
2.43.0

[PATCH AUTOSEL 5.4 6/7] drm/amd/display: Reset freesync config before update new state

[Sasha Levin]

From: Tom Chung <chiahsuan.chung@amd.com>

[ Upstream commit 6b8487cdf9fc7bae707519ac5b5daeca18d1e85b ]

[Why]
Sometimes the new_crtc_state->vrr_infopacket did not sync up with the
current state.
It will affect the update_freesync_state_on_stream() does not update
the state correctly.

[How]
Reset the freesync config before get_freesync_config_for_crtc() to
make sure we have the correct new_crtc_state for VRR.

Reviewed-by: Sun peng Li <sunpeng.li@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 3bfc4aa328c6f..d400f9f4ca7bd 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6878,6 +6878,7 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,
 	}
 
 	/* Update Freesync settings. */
+	reset_freesync_config_for_crtc(dm_new_crtc_state);
 	get_freesync_config_for_crtc(dm_new_crtc_state,
 				     dm_new_conn_state);
 
-- 
2.43.0

[PATCH AUTOSEL 5.4 7/7] fs: better handle deep ancestor chains in is_subdir()

[Sasha Levin]

From: Christian Brauner <brauner@kernel.org>

[ Upstream commit 391b59b045004d5b985d033263ccba3e941a7740 ]

Jan reported that 'cd ..' may take a long time in deep directory
hierarchies under a bind-mount. If concurrent renames happen it is
possible to livelock in is_subdir() because it will keep retrying.

Change is_subdir() from simply retrying over and over to retry once and
then acquire the rename lock to handle deep ancestor chains better. The
list of alternatives to this approach were less then pleasant. Change
the scope of rcu lock to cover the whole walk while at it.

A big thanks to Jan and Linus. Both Jan and Linus had proposed
effectively the same thing just that one version ended up being slightly
more elegant.

Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/dcache.c | 31 ++++++++++++++-----------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index 43864a276faa2..7d2e689fd3100 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -3067,28 +3067,25 @@ EXPORT_SYMBOL(d_splice_alias);
   
 bool is_subdir(struct dentry *new_dentry, struct dentry *old_dentry)
 {
-	bool result;
+	bool subdir;
 	unsigned seq;
 
 	if (new_dentry == old_dentry)
 		return true;
 
-	do {
-		/* for restarting inner loop in case of seq retry */
-		seq = read_seqbegin(&rename_lock);
-		/*
-		 * Need rcu_readlock to protect against the d_parent trashing
-		 * due to d_move
-		 */
-		rcu_read_lock();
-		if (d_ancestor(old_dentry, new_dentry))
-			result = true;
-		else
-			result = false;
-		rcu_read_unlock();
-	} while (read_seqretry(&rename_lock, seq));
-
-	return result;
+	/* Access d_parent under rcu as d_move() may change it. */
+	rcu_read_lock();
+	seq = read_seqbegin(&rename_lock);
+	subdir = d_ancestor(old_dentry, new_dentry);
+	 /* Try lockless once... */
+	if (read_seqretry(&rename_lock, seq)) {
+		/* ...else acquire lock for progress even on deep chains. */
+		read_seqlock_excl(&rename_lock);
+		subdir = d_ancestor(old_dentry, new_dentry);
+		read_sequnlock_excl(&rename_lock);
+	}
+	rcu_read_unlock();
+	return subdir;
 }
 EXPORT_SYMBOL(is_subdir);
 
-- 
2.43.0