diff mbox series

[net,1/3] idpf: fix memory leaks and crashes while performing a soft reset

Message ID 20240806220923.3359860-2-anthony.l.nguyen@intel.com (mailing list archive)
State Accepted
Commit f01032a2ca099ec8d619aaa916c3762aa62495df
Delegated to: Netdev Maintainers
Headers show
Series idpf: fix 3 bugs revealed by the Chapter I | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 29 this patch: 29
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers fail 1 blamed authors not CCed: willemb@google.com; 1 maintainers not CCed: willemb@google.com
netdev/build_clang success Errors and warnings before: 29 this patch: 29
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 29 this patch: 29
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 75 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 35 this patch: 35
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-08-07--03-00 (tests: 707)

Commit Message

Tony Nguyen Aug. 6, 2024, 10:09 p.m. UTC 
From: Alexander Lobakin <aleksander.lobakin@intel.com>

The second tagged commit introduced a UAF, as it removed restoring
q_vector->vport pointers after reinitializating the structures.
This is due to that all queue allocation functions are performed here
with the new temporary vport structure and those functions rewrite
the backpointers to the vport. Then, this new struct is freed and
the pointers start leading to nowhere.

But generally speaking, the current logic is very fragile. It claims
to be more reliable when the system is low on memory, but in fact, it
consumes two times more memory as at the moment of running this
function, there are two vports allocated with their queues and vectors.
Moreover, it claims to prevent the driver from running into "bad state",
but in fact, any error during the rebuild leaves the old vport in the
partially allocated state.
Finally, if the interface is down when the function is called, it always
allocates a new queue set, but when the user decides to enable the
interface later on, vport_open() allocates them once again, IOW there's
a clear memory leak here.

Just don't allocate a new queue set when performing a reset, that solves
crashes and memory leaks. Readd the old queue number and reopen the
interface on rollback - that solves limbo states when the device is left
disabled and/or without HW queues enabled.

Fixes: 02cbfba1add5 ("idpf: add ethtool callbacks")
Fixes: e4891e4687c8 ("idpf: split &idpf_queue into 4 strictly-typed queue structures")
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/idpf/idpf_lib.c | 30 +++++++++++-----------
 1 file changed, 15 insertions(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/intel/idpf/idpf_lib.c b/drivers/net/ethernet/intel/idpf/idpf_lib.c
index 5dbf2b4ba1b0..10b884dd3475 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_lib.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_lib.c
@@ -1335,9 +1335,8 @@  static void idpf_rx_init_buf_tail(struct idpf_vport *vport)
 /**
  * idpf_vport_open - Bring up a vport
  * @vport: vport to bring up
- * @alloc_res: allocate queue resources
  */
-static int idpf_vport_open(struct idpf_vport *vport, bool alloc_res)
+static int idpf_vport_open(struct idpf_vport *vport)
 {
 	struct idpf_netdev_priv *np = netdev_priv(vport->netdev);
 	struct idpf_adapter *adapter = vport->adapter;
@@ -1350,11 +1349,9 @@  static int idpf_vport_open(struct idpf_vport *vport, bool alloc_res)
 	/* we do not allow interface up just yet */
 	netif_carrier_off(vport->netdev);
 
-	if (alloc_res) {
-		err = idpf_vport_queues_alloc(vport);
-		if (err)
-			return err;
-	}
+	err = idpf_vport_queues_alloc(vport);
+	if (err)
+		return err;
 
 	err = idpf_vport_intr_alloc(vport);
 	if (err) {
@@ -1539,7 +1536,7 @@  void idpf_init_task(struct work_struct *work)
 	np = netdev_priv(vport->netdev);
 	np->state = __IDPF_VPORT_DOWN;
 	if (test_and_clear_bit(IDPF_VPORT_UP_REQUESTED, vport_config->flags))
-		idpf_vport_open(vport, true);
+		idpf_vport_open(vport);
 
 	/* Spawn and return 'idpf_init_task' work queue until all the
 	 * default vports are created
@@ -1898,9 +1895,6 @@  int idpf_initiate_soft_reset(struct idpf_vport *vport,
 		goto free_vport;
 	}
 
-	err = idpf_vport_queues_alloc(new_vport);
-	if (err)
-		goto free_vport;
 	if (current_state <= __IDPF_VPORT_DOWN) {
 		idpf_send_delete_queues_msg(vport);
 	} else {
@@ -1932,17 +1926,23 @@  int idpf_initiate_soft_reset(struct idpf_vport *vport,
 
 	err = idpf_set_real_num_queues(vport);
 	if (err)
-		goto err_reset;
+		goto err_open;
 
 	if (current_state == __IDPF_VPORT_UP)
-		err = idpf_vport_open(vport, false);
+		err = idpf_vport_open(vport);
 
 	kfree(new_vport);
 
 	return err;
 
 err_reset:
-	idpf_vport_queues_rel(new_vport);
+	idpf_send_add_queues_msg(vport, vport->num_txq, vport->num_complq,
+				 vport->num_rxq, vport->num_bufq);
+
+err_open:
+	if (current_state == __IDPF_VPORT_UP)
+		idpf_vport_open(vport);
+
 free_vport:
 	kfree(new_vport);
 
@@ -2171,7 +2171,7 @@  static int idpf_open(struct net_device *netdev)
 	idpf_vport_ctrl_lock(netdev);
 	vport = idpf_netdev_to_vport(netdev);
 
-	err = idpf_vport_open(vport, true);
+	err = idpf_vport_open(vport);
 
 	idpf_vport_ctrl_unlock(netdev);