This is a note to let you know that I've just added the patch titled
sfc: Fix use-after-free due to selftest_work
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sfc-fix-use-after-free-due-to-selftest_work.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 19540a6ef1f02c4dce73c44da42c1fce8db551d8
Author: Ding Hui <dinghui@xxxxxxxxxxxxxx>
Date: Fri Apr 14 23:23:06 2023 +0800
sfc: Fix use-after-free due to selftest_work
[ Upstream commit a80bb8e7233b2ad6ff119646b6e33fb3edcec37b ]
There is a use-after-free scenario that is:
When the NIC is down, user set mac address or vlan tag to VF,
the xxx_set_vf_mac() or xxx_set_vf_vlan() will invoke efx_net_stop()
and efx_net_open(), since netif_running() is false, the port will not
start and keep port_enabled false, but selftest_work is scheduled
in efx_net_open().
If we remove the device before selftest_work run, the efx_stop_port()
will not be called since the NIC is down, and then efx is freed,
we will soon get a UAF in run_timer_softirq() like this:
[ 1178.907941] ==================================================================
[ 1178.907948] BUG: KASAN: use-after-free in run_timer_softirq+0xdea/0xe90
[ 1178.907950] Write of size 8 at addr ff11001f449cdc80 by task swapper/47/0
[ 1178.907950]
[ 1178.907953] CPU: 47 PID: 0 Comm: swapper/47 Kdump: loaded Tainted: G O --------- -t - 4.18.0 #1
[ 1178.907954] Hardware name: SANGFOR X620G40/WI2HG-208T1061A, BIOS SPYH051032-U01 04/01/2022
[ 1178.907955] Call Trace:
[ 1178.907956] <IRQ>
[ 1178.907960] dump_stack+0x71/0xab
[ 1178.907963] print_address_description+0x6b/0x290
[ 1178.907965] ? run_timer_softirq+0xdea/0xe90
[ 1178.907967] kasan_report+0x14a/0x2b0
[ 1178.907968] run_timer_softirq+0xdea/0xe90
[ 1178.907971] ? init_timer_key+0x170/0x170
[ 1178.907973] ? hrtimer_cancel+0x20/0x20
[ 1178.907976] ? sched_clock+0x5/0x10
[ 1178.907978] ? sched_clock_cpu+0x18/0x170
[ 1178.907981] __do_softirq+0x1c8/0x5fa
[ 1178.907985] irq_exit+0x213/0x240
[ 1178.907987] smp_apic_timer_interrupt+0xd0/0x330
[ 1178.907989] apic_timer_interrupt+0xf/0x20
[ 1178.907990] </IRQ>
[ 1178.907991] RIP: 0010:mwait_idle+0xae/0x370
If the NIC is not actually brought up, there is no need to schedule
selftest_work, so let's move invoking efx_selftest_async_start()
into efx_start_all(), and it will be canceled by broughting down.
Fixes: dd40781e3a4e ("sfc: Run event/IRQ self-test asynchronously when interface is brought up")
Fixes: e340be923012 ("sfc: add ndo_set_vf_mac() function for EF10")
Debugged-by: Huang Cun <huangcun@xxxxxxxxxxxxxx>
Cc: Donglin Peng <pengdonglin@xxxxxxxxxxxxxx>
Suggested-by: Martin Habets <habetsm.xilinx@xxxxxxxxx>
Signed-off-by: Ding Hui <dinghui@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index 6a1bff54bc6c3..e6aedd8ebd750 100644
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -541,7 +541,6 @@ int efx_net_open(struct net_device *net_dev)
else
efx->state = STATE_NET_UP;
- efx_selftest_async_start(efx);
return 0;
}
diff --git a/drivers/net/ethernet/sfc/efx_common.c b/drivers/net/ethernet/sfc/efx_common.c
index cc30524c2fe45..361687de308dc 100644
--- a/drivers/net/ethernet/sfc/efx_common.c
+++ b/drivers/net/ethernet/sfc/efx_common.c
@@ -544,6 +544,8 @@ void efx_start_all(struct efx_nic *efx)
/* Start the hardware monitor if there is one */
efx_start_monitor(efx);
+ efx_selftest_async_start(efx);
+
/* Link state detection is normally event-driven; we have
* to poll now because we could have missed a change
*/
