diff mbox series

net: atlantic: fixed double free when constrained memory conditions

Message ID 20231204162040.923-1-irusskikh@marvell.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net: atlantic: fixed double free when constrained memory conditions | expand

Checks

Context Check Description
netdev/series_format warning Single patches do not need cover letters; Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/ynl success Generated files up to date; no warnings/errors;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1119 this patch: 1119
netdev/cc_maintainers warning 9 maintainers not CCed: pabeni@redhat.com john.fastabend@gmail.com hawk@kernel.org richardcochran@gmail.com epomozov@marvell.com daniel@iogearbox.net ast@kernel.org bpf@vger.kernel.org edumazet@google.com
netdev/build_clang success Errors and warnings before: 1142 this patch: 1142
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: 1147 this patch: 1147
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 243 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Igor Russkikh Dec. 4, 2023, 4:20 p.m. UTC 
Driver has a logic leak in ring data allocation/free,
where double free may happen in aq_ring_free if system is under
stress and driver init/deinit is happening.

The probability is higher to get this during suspend/resume cycle.

Verification was done simulating same conditions with

    stress -m 2000 --vm-bytes 20M --vm-hang 10 --backoff 1000
    while true; do sudo ifconfig enp1s0 down; sudo ifconfig enp1s0 up; done

Fixed by explicitly clearing pointers to NULL, also eliminate two
levels of aq_ring_free invocation.

Fixes: 018423e90bee ("net: ethernet: aquantia: Add ring support code")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Closes: https://lore.kernel.org/netdev/CAHk-=wiZZi7FcvqVSUirHBjx0bBUZ4dFrMDVLc3+3HCrtq0rBA@mail.gmail.com/
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
---
 .../net/ethernet/aquantia/atlantic/aq_ptp.c   | 28 +++-----
 .../net/ethernet/aquantia/atlantic/aq_ring.c  | 66 ++++++-------------
 .../net/ethernet/aquantia/atlantic/aq_ring.h  | 22 +++----
 .../net/ethernet/aquantia/atlantic/aq_vec.c   | 23 +++----
 4 files changed, 51 insertions(+), 88 deletions(-)

Comments

Jakub Kicinski Dec. 6, 2023, 3:33 a.m. UTC | #1 
On Mon, 4 Dec 2023 17:20:40 +0100 Igor Russkikh wrote:
> Driver has a logic leak in ring data allocation/free,
> where double free may happen in aq_ring_free if system is under
> stress and driver init/deinit is happening.
> 
> The probability is higher to get this during suspend/resume cycle.
> 
> Verification was done simulating same conditions with
> 
>     stress -m 2000 --vm-bytes 20M --vm-hang 10 --backoff 1000
>     while true; do sudo ifconfig enp1s0 down; sudo ifconfig enp1s0 up; done
> 
> Fixed by explicitly clearing pointers to NULL, also eliminate two
> levels of aq_ring_free invocation.

The change of the return type plays no functional role in the fix,
right?

I think it'd make the change far more readable if that was a separate
patch. And if it's a separate, non-functional patch, it should go
to net-next, rather than with the fix to net.
Igor Russkikh Dec. 7, 2023, 9:29 a.m. UTC | #2 
>>
>> Fixed by explicitly clearing pointers to NULL, also eliminate two
>> levels of aq_ring_free invocation.
> 
> The change of the return type plays no functional role in the fix,
> right?
> 
> I think it'd make the change far more readable if that was a separate
> patch. And if it's a separate, non-functional patch, it should go
> to net-next, rather than with the fix to net.

Makes sense, will split the patch.

Thanks
  Igor
diff mbox series

Patch

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ptp.c b/drivers/net/ethernet/aquantia/atlantic/aq_ptp.c
index 80b44043e6c5..7157fffd1cc3 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ptp.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ptp.c
@@ -953,8 +953,6 @@  int aq_ptp_ring_alloc(struct aq_nic_s *aq_nic)
 {
 	struct aq_ptp_s *aq_ptp = aq_nic->aq_ptp;
 	unsigned int tx_ring_idx, rx_ring_idx;
-	struct aq_ring_s *hwts;
-	struct aq_ring_s *ring;
 	int err;
 
 	if (!aq_ptp)
@@ -962,29 +960,23 @@  int aq_ptp_ring_alloc(struct aq_nic_s *aq_nic)
 
 	tx_ring_idx = aq_ptp_ring_idx(aq_nic->aq_nic_cfg.tc_mode);
 
-	ring = aq_ring_tx_alloc(&aq_ptp->ptp_tx, aq_nic,
-				tx_ring_idx, &aq_nic->aq_nic_cfg);
-	if (!ring) {
-		err = -ENOMEM;
+	err = aq_ring_tx_alloc(&aq_ptp->ptp_tx, aq_nic,
+			       tx_ring_idx, &aq_nic->aq_nic_cfg);
+	if (err)
 		goto err_exit;
-	}
 
 	rx_ring_idx = aq_ptp_ring_idx(aq_nic->aq_nic_cfg.tc_mode);
 
-	ring = aq_ring_rx_alloc(&aq_ptp->ptp_rx, aq_nic,
-				rx_ring_idx, &aq_nic->aq_nic_cfg);
-	if (!ring) {
-		err = -ENOMEM;
+	err = aq_ring_rx_alloc(&aq_ptp->ptp_rx, aq_nic,
+			       rx_ring_idx, &aq_nic->aq_nic_cfg);
+	if (err)
 		goto err_exit_ptp_tx;
-	}
 
-	hwts = aq_ring_hwts_rx_alloc(&aq_ptp->hwts_rx, aq_nic, PTP_HWST_RING_IDX,
-				     aq_nic->aq_nic_cfg.rxds,
-				     aq_nic->aq_nic_cfg.aq_hw_caps->rxd_size);
-	if (!hwts) {
-		err = -ENOMEM;
+	err = aq_ring_hwts_rx_alloc(&aq_ptp->hwts_rx, aq_nic, PTP_HWST_RING_IDX,
+				    aq_nic->aq_nic_cfg.rxds,
+				    aq_nic->aq_nic_cfg.aq_hw_caps->rxd_size);
+	if (err)
 		goto err_exit_ptp_rx;
-	}
 
 	err = aq_ptp_skb_ring_init(&aq_ptp->skb_ring, aq_nic->aq_nic_cfg.rxds);
 	if (err != 0) {
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index 4de22eed099a..ae239bb4c29b 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -132,8 +132,8 @@  static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf)
 	return 0;
 }
 
-static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self,
-				       struct aq_nic_s *aq_nic)
+static int aq_ring_alloc(struct aq_ring_s *self,
+			 struct aq_nic_s *aq_nic)
 {
 	int err = 0;
 
@@ -156,46 +156,29 @@  static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self,
 err_exit:
 	if (err < 0) {
 		aq_ring_free(self);
-		self = NULL;
 	}
 
-	return self;
+	return err;
 }
 
-struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
-				   struct aq_nic_s *aq_nic,
-				   unsigned int idx,
-				   struct aq_nic_cfg_s *aq_nic_cfg)
+int aq_ring_tx_alloc(struct aq_ring_s *self,
+		     struct aq_nic_s *aq_nic,
+		     unsigned int idx,
+		     struct aq_nic_cfg_s *aq_nic_cfg)
 {
-	int err = 0;
-
 	self->aq_nic = aq_nic;
 	self->idx = idx;
 	self->size = aq_nic_cfg->txds;
 	self->dx_size = aq_nic_cfg->aq_hw_caps->txd_size;
 
-	self = aq_ring_alloc(self, aq_nic);
-	if (!self) {
-		err = -ENOMEM;
-		goto err_exit;
-	}
-
-err_exit:
-	if (err < 0) {
-		aq_ring_free(self);
-		self = NULL;
-	}
-
-	return self;
+	return aq_ring_alloc(self, aq_nic);
 }
 
-struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
-				   struct aq_nic_s *aq_nic,
-				   unsigned int idx,
-				   struct aq_nic_cfg_s *aq_nic_cfg)
+int aq_ring_rx_alloc(struct aq_ring_s *self,
+		     struct aq_nic_s *aq_nic,
+		     unsigned int idx,
+		     struct aq_nic_cfg_s *aq_nic_cfg)
 {
-	int err = 0;
-
 	self->aq_nic = aq_nic;
 	self->idx = idx;
 	self->size = aq_nic_cfg->rxds;
@@ -217,22 +200,10 @@  struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
 		self->tail_size = 0;
 	}
 
-	self = aq_ring_alloc(self, aq_nic);
-	if (!self) {
-		err = -ENOMEM;
-		goto err_exit;
-	}
-
-err_exit:
-	if (err < 0) {
-		aq_ring_free(self);
-		self = NULL;
-	}
-
-	return self;
+	return aq_ring_alloc(self, aq_nic);
 }
 
-struct aq_ring_s *
+int
 aq_ring_hwts_rx_alloc(struct aq_ring_s *self, struct aq_nic_s *aq_nic,
 		      unsigned int idx, unsigned int size, unsigned int dx_size)
 {
@@ -250,10 +221,10 @@  aq_ring_hwts_rx_alloc(struct aq_ring_s *self, struct aq_nic_s *aq_nic,
 					   GFP_KERNEL);
 	if (!self->dx_ring) {
 		aq_ring_free(self);
-		return NULL;
+		return -ENOMEM;
 	}
 
-	return self;
+	return 0;
 }
 
 int aq_ring_init(struct aq_ring_s *self, const enum atl_ring_type ring_type)
@@ -932,11 +903,14 @@  void aq_ring_free(struct aq_ring_s *self)
 		return;
 
 	kfree(self->buff_ring);
+	self->buff_ring = NULL;
 
-	if (self->dx_ring)
+	if (self->dx_ring) {
 		dma_free_coherent(aq_nic_get_dev(self->aq_nic),
 				  self->size * self->dx_size, self->dx_ring,
 				  self->dx_ring_pa);
+		self->dx_ring = NULL;
+	}
 }
 
 unsigned int aq_ring_fill_stats_data(struct aq_ring_s *self, u64 *data)
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
index 0a6c34438c1d..52847310740a 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
@@ -183,14 +183,14 @@  static inline unsigned int aq_ring_avail_dx(struct aq_ring_s *self)
 		self->sw_head - self->sw_tail - 1);
 }
 
-struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
-				   struct aq_nic_s *aq_nic,
-				   unsigned int idx,
-				   struct aq_nic_cfg_s *aq_nic_cfg);
-struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
-				   struct aq_nic_s *aq_nic,
-				   unsigned int idx,
-				   struct aq_nic_cfg_s *aq_nic_cfg);
+int aq_ring_tx_alloc(struct aq_ring_s *self,
+		     struct aq_nic_s *aq_nic,
+		     unsigned int idx,
+		     struct aq_nic_cfg_s *aq_nic_cfg);
+int aq_ring_rx_alloc(struct aq_ring_s *self,
+		     struct aq_nic_s *aq_nic,
+		     unsigned int idx,
+		     struct aq_nic_cfg_s *aq_nic_cfg);
 
 int aq_ring_init(struct aq_ring_s *self, const enum atl_ring_type ring_type);
 void aq_ring_rx_deinit(struct aq_ring_s *self);
@@ -207,9 +207,9 @@  int aq_ring_rx_clean(struct aq_ring_s *self,
 		     int budget);
 int aq_ring_rx_fill(struct aq_ring_s *self);
 
-struct aq_ring_s *aq_ring_hwts_rx_alloc(struct aq_ring_s *self,
-		struct aq_nic_s *aq_nic, unsigned int idx,
-		unsigned int size, unsigned int dx_size);
+int aq_ring_hwts_rx_alloc(struct aq_ring_s *self,
+			  struct aq_nic_s *aq_nic, unsigned int idx,
+			  unsigned int size, unsigned int dx_size);
 void aq_ring_hwts_rx_clean(struct aq_ring_s *self, struct aq_nic_s *aq_nic);
 
 unsigned int aq_ring_fill_stats_data(struct aq_ring_s *self, u64 *data);
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
index f5db1c44e9b9..9769ab4f9bef 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
@@ -136,35 +136,32 @@  int aq_vec_ring_alloc(struct aq_vec_s *self, struct aq_nic_s *aq_nic,
 		const unsigned int idx_ring = AQ_NIC_CFG_TCVEC2RING(aq_nic_cfg,
 								    i, idx);
 
-		ring = aq_ring_tx_alloc(&self->ring[i][AQ_VEC_TX_ID], aq_nic,
-					idx_ring, aq_nic_cfg);
-		if (!ring) {
-			err = -ENOMEM;
+		ring = &self->ring[i][AQ_VEC_TX_ID];
+		err = aq_ring_tx_alloc(ring, aq_nic, idx_ring, aq_nic_cfg);
+		if (err)
 			goto err_exit;
-		}
 
 		++self->tx_rings;
 
 		aq_nic_set_tx_ring(aq_nic, idx_ring, ring);
 
-		if (xdp_rxq_info_reg(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq,
+		ring = &self->ring[i][AQ_VEC_RX_ID];
+		if (xdp_rxq_info_reg(&ring->xdp_rxq,
 				     aq_nic->ndev, idx,
 				     self->napi.napi_id) < 0) {
 			err = -ENOMEM;
 			goto err_exit;
 		}
-		if (xdp_rxq_info_reg_mem_model(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq,
+		if (xdp_rxq_info_reg_mem_model(&ring->xdp_rxq,
 					       MEM_TYPE_PAGE_SHARED, NULL) < 0) {
-			xdp_rxq_info_unreg(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq);
+			xdp_rxq_info_unreg(&ring->xdp_rxq);
 			err = -ENOMEM;
 			goto err_exit;
 		}
 
-		ring = aq_ring_rx_alloc(&self->ring[i][AQ_VEC_RX_ID], aq_nic,
-					idx_ring, aq_nic_cfg);
-		if (!ring) {
-			xdp_rxq_info_unreg(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq);
-			err = -ENOMEM;
+		err = aq_ring_rx_alloc(ring, aq_nic, idx_ring, aq_nic_cfg);
+		if (err) {
+			xdp_rxq_info_unreg(&ring->xdp_rxq);
 			goto err_exit;
 		}