6.6-stable review patch. If anyone has any objections, please let me know.
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From: Dawid Osuchowski dawid.osuchowski@linux.intel.com
[ Upstream commit d11a67634227f9f9da51938af085fb41a733848f ]
Ethtool callbacks can be executed while reset is in progress and try to access deleted resources, e.g. getting coalesce settings can result in a NULL pointer dereference seen below.
Reproduction steps: Once the driver is fully initialized, trigger reset: # echo 1 > /sys/class/net/<interface>/device/reset when reset is in progress try to get coalesce settings using ethtool: # ethtool -c <interface>
BUG: kernel NULL pointer dereference, address: 0000000000000020 PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 11 PID: 19713 Comm: ethtool Tainted: G S 6.10.0-rc7+ #7 RIP: 0010:ice_get_q_coalesce+0x2e/0xa0 [ice] RSP: 0018:ffffbab1e9bcf6a8 EFLAGS: 00010206 RAX: 000000000000000c RBX: ffff94512305b028 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9451c3f2e588 RDI: ffff9451c3f2e588 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffff9451c3f2e580 R11: 000000000000001f R12: ffff945121fa9000 R13: ffffbab1e9bcf760 R14: 0000000000000013 R15: ffffffff9e65dd40 FS: 00007faee5fbe740(0000) GS:ffff94546fd80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 0000000106c2e005 CR4: 00000000001706f0 Call Trace: <TASK> ice_get_coalesce+0x17/0x30 [ice] coalesce_prepare_data+0x61/0x80 ethnl_default_doit+0xde/0x340 genl_family_rcv_msg_doit+0xf2/0x150 genl_rcv_msg+0x1b3/0x2c0 netlink_rcv_skb+0x5b/0x110 genl_rcv+0x28/0x40 netlink_unicast+0x19c/0x290 netlink_sendmsg+0x222/0x490 __sys_sendto+0x1df/0x1f0 __x64_sys_sendto+0x24/0x30 do_syscall_64+0x82/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7faee60d8e27
Calling netif_device_detach() before reset makes the net core not call the driver when ethtool command is issued, the attempt to execute an ethtool command during reset will result in the following message:
netlink error: No such device
instead of NULL pointer dereference. Once reset is done and ice_rebuild() is executing, the netif_device_attach() is called to allow for ethtool operations to occur again in a safe manner.
Fixes: fcea6f3da546 ("ice: Add stats and ethtool support") Suggested-by: Jakub Kicinski kuba@kernel.org Reviewed-by: Igor Bagnucki igor.bagnucki@intel.com Signed-off-by: Dawid Osuchowski dawid.osuchowski@linux.intel.com Tested-by: Pucha Himasekhar Reddy himasekharx.reddy.pucha@intel.com (A Contingent worker at Intel) Reviewed-by: Michal Schmidt mschmidt@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_main.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c index 3f254ce0d6db..ffe6e74b9fea 100644 --- a/drivers/net/ethernet/intel/ice/ice_main.c +++ b/drivers/net/ethernet/intel/ice/ice_main.c @@ -606,6 +606,9 @@ ice_prepare_for_reset(struct ice_pf *pf, enum ice_reset_req reset_type) memset(&vsi->mqprio_qopt, 0, sizeof(vsi->mqprio_qopt)); } } + + if (vsi->netdev) + netif_device_detach(vsi->netdev); skip:
/* clear SW filtering DB */ @@ -7295,6 +7298,7 @@ static void ice_update_pf_netdev_link(struct ice_pf *pf) */ static void ice_rebuild(struct ice_pf *pf, enum ice_reset_req reset_type) { + struct ice_vsi *vsi = ice_get_main_vsi(pf); struct device *dev = ice_pf_to_dev(pf); struct ice_hw *hw = &pf->hw; bool dvm; @@ -7447,6 +7451,9 @@ static void ice_rebuild(struct ice_pf *pf, enum ice_reset_req reset_type) ice_rebuild_arfs(pf); }
+ if (vsi && vsi->netdev) + netif_device_attach(vsi->netdev); + ice_update_pf_netdev_link(pf);
/* tell the firmware we are up */