[PATCH 5.17 072/219] ice: arfs: fix use-after-free when freeing @rx_cpu_rmap

Greg Kroah-Hartman
2022-04-18T12:22:06Z

From: Alexander Lobakin <alexandr.lobakin@intel.com>

[ Upstream commit d7442f512b71fc63a99c8a801422dde4fbbf9f93 ]

The CI testing bots triggered the following splat:

[ 718.203054] BUG: KASAN: use-after-free in free_irq_cpu_rmap+0x53/0x80
[ 718.206349] Read of size 4 at addr ffff8881bd127e00 by task sh/20834
[ 718.212852] CPU: 28 PID: 20834 Comm: sh Kdump: loaded Tainted: G S W IOE 5.17.0-rc8_nextqueue-devqueue-02643-g23f3121aca93 #1
[ 718.219695] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0012.070720200218 07/07/2020
[ 718.223418] Call Trace:
[ 718.227139]
[ 718.230783] dump_stack_lvl+0x33/0x42
[ 718.234431] print_address_description.constprop.9+0x21/0x170
[ 718.238177] ? free_irq_cpu_rmap+0x53/0x80
[ 718.241885] ? free_irq_cpu_rmap+0x53/0x80
[ 718.245539] kasan_report.cold.18+0x7f/0x11b
[ 718.249197] ? free_irq_cpu_rmap+0x53/0x80
[ 718.252852] free_irq_cpu_rmap+0x53/0x80
[ 718.256471] ice_free_cpu_rx_rmap.part.11+0x37/0x50 [ice]
[ 718.260174] ice_remove_arfs+0x5f/0x70 [ice]
[ 718.263810] ice_rebuild_arfs+0x3b/0x70 [ice]
[ 718.267419] ice_rebuild+0x39c/0xb60 [ice]
[ 718.270974] ? asm_sysvec_apic_timer_interrupt+0x12/0x20
[ 718.274472] ? ice_init_phy_user_cfg+0x360/0x360 [ice]
[ 718.278033] ? delay_tsc+0x4a/0xb0
[ 718.281513] ? preempt_count_sub+0x14/0xc0
[ 718.284984] ? delay_tsc+0x8f/0xb0
[ 718.288463] ice_do_reset+0x92/0xf0 [ice]
[ 718.292014] ice_pci_err_resume+0x91/0xf0 [ice]
[ 718.295561] pci_reset_function+0x53/0x80
<...>
[ 718.393035] Allocated by task 690:
[ 718.433497] Freed by task 20834:
[ 718.495688] Last potentially related work creation:
[ 718.568966] The buggy address belongs to the object at ffff8881bd127e00
which belongs to the cache kmalloc-96 of size 96
[ 718.574085] The buggy address is located 0 bytes inside of
96-byte region [ffff8881bd127e00, ffff8881bd127e60)
[ 718.579265] The buggy address belongs to the page:
[ 718.598905] Memory state around the buggy address:
[ 718.601809] ffff8881bd127d00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[ 718.604796] ffff8881bd127d80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
[ 718.607794] >ffff8881bd127e00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
[ 718.610811] ^
[ 718.613819] ffff8881bd127e80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 718.617107] ffff8881bd127f00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc

This is due to that free_irq_cpu_rmap() is always being called
*after* (devm_)free_irq() and thus it tries to work with IRQ descs
already freed. For example, on device reset the driver frees the
rmap right before allocating a new one (the splat above).
Make rmap creation and freeing function symmetrical with
{request,free}_irq() calls i.e. do that on ifup/ifdown instead
of device probe/remove/resume. These operations can be performed
independently from the actual device aRFS configuration.
Also, make sure ice_vsi_free_irq() clears IRQ affinity notifiers
only when aRFS is disabled -- otherwise, CPU rmap sets and clears
its own and they must not be touched manually.

Fixes: 28bf26724fdb0 ("ice: Implement aRFS")
Co-developed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Tested-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/intel/ice/ice_arfs.c | 9 ++-------
drivers/net/ethernet/intel/ice/ice_lib.c | 5 ++++-
drivers/net/ethernet/intel/ice/ice_main.c | 18 ++++++++----------
3 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_arfs.c b/drivers/net/ethernet/intel/ice/ice_arfs.c
index 5daade32ea62..fba178e07600 100644
--- a/drivers/net/ethernet/intel/ice/ice_arfs.c
+++ b/drivers/net/ethernet/intel/ice/ice_arfs.c
@@ -577,7 +577,7 @@ void ice_free_cpu_rx_rmap(struct ice_vsi *vsi)
{
struct net_device *netdev;

- if (!vsi || vsi->type != ICE_VSI_PF || !vsi->arfs_fltr_list)
+ if (!vsi || vsi->type != ICE_VSI_PF)
return;

netdev = vsi->netdev;
@@ -599,7 +599,7 @@ int ice_set_cpu_rx_rmap(struct ice_vsi *vsi)
int base_idx, i;

if (!vsi || vsi->type != ICE_VSI_PF)
- return -EINVAL;
+ return 0;

pf = vsi->back;
netdev = vsi->netdev;
@@ -636,7 +636,6 @@ void ice_remove_arfs(struct ice_pf *pf)
if (!pf_vsi)
return;

- ice_free_cpu_rx_rmap(pf_vsi);
ice_clear_arfs(pf_vsi);
}

@@ -653,9 +652,5 @@ void ice_rebuild_arfs(struct ice_pf *pf)
return;

ice_remove_arfs(pf);
- if (ice_set_cpu_rx_rmap(pf_vsi)) {
- dev_err(ice_pf_to_dev(pf), "Failed to rebuild aRFS\n");
- return;
- }
ice_init_arfs(pf_vsi);
}
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index 5fd2bbeab2d1..15bb6f001a04 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -2869,6 +2869,8 @@ void ice_vsi_free_irq(struct ice_vsi *vsi)
return;

vsi->irqs_ready = false;
+ ice_free_cpu_rx_rmap(vsi);
+
ice_for_each_q_vector(vsi, i) {
u16 vector = i + base;
int irq_num;
@@ -2882,7 +2884,8 @@ void ice_vsi_free_irq(struct ice_vsi *vsi)
continue;

/* clear the affinity notifier in the IRQ descriptor */
- irq_set_affinity_notifier(irq_num, NULL);
+ if (!IS_ENABLED(CONFIG_RFS_ACCEL))
+ irq_set_affinity_notifier(irq_num, NULL);

/* clear the affinity_mask in the IRQ descriptor */
irq_set_affinity_hint(irq_num, NULL);
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index db2e02e673a7..2de2bbbca1e9 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -2494,6 +2494,13 @@ static int ice_vsi_req_irq_msix(struct ice_vsi *vsi, char *basename)
irq_set_affinity_hint(irq_num, &q_vector->affinity_mask);
}

+ err = ice_set_cpu_rx_rmap(vsi);
+ if (err) {
+ netdev_err(vsi->netdev, "Failed to setup CPU RMAP on VSI %u: %pe\n",
+ vsi->vsi_num, ERR_PTR(err));
+ goto free_q_irqs;
+ }
+
vsi->irqs_ready = true;
return 0;

@@ -3605,20 +3612,12 @@ static int ice_setup_pf_sw(struct ice_pf *pf)
*/
ice_napi_add(vsi);

- status = ice_set_cpu_rx_rmap(vsi);
- if (status) {
- dev_err(dev, "Failed to set CPU Rx map VSI %d error %d\n",
- vsi->vsi_num, status);
- goto unroll_napi_add;
- }
status = ice_init_mac_fltr(pf);
if (status)
- goto free_cpu_rx_map;
+ goto unroll_napi_add;

return 0;

-free_cpu_rx_map:
- ice_free_cpu_rx_rmap(vsi);
unroll_napi_add:
ice_tc_indir_block_unregister(vsi);
unroll_cfg_netdev:
@@ -5076,7 +5075,6 @@ static int __maybe_unused ice_suspend(struct device *dev)
continue;
ice_vsi_free_q_vectors(pf->vsi[v]);
}
- ice_free_cpu_rx_rmap(ice_get_main_vsi(pf));
ice_clear_interrupt_scheme(pf);

pci_save_state(pdev);
--
2.35.1