Commit 2747328b authored by Sreekanth Reddy's avatar Sreekanth Reddy Committed by Jakub Kicinski
Browse files

bnxt_en: Fix memory corruption when FW resources change during ifdown 



bnxt_set_dflt_rings() assumes that it is always called before any TC has
been created.  So it doesn't take bp->num_tc into account and assumes
that it is always 0 or 1.

In the FW resource or capability change scenario, the FW will return
flags in bnxt_hwrm_if_change() that will cause the driver to
reinitialize and call bnxt_cancel_reservations().  This will lead to
bnxt_init_dflt_ring_mode() calling bnxt_set_dflt_rings() and bp->num_tc
may be greater than 1.  This will cause bp->tx_ring[] to be sized too
small and cause memory corruption in bnxt_alloc_cp_rings().

Fix it by properly scaling the TX rings by bp->num_tc in the code
paths mentioned above.  Add 2 helper functions to determine
bp->tx_nr_rings and bp->tx_nr_rings_per_tc.

Fixes: ec5d31e3 ("bnxt_en: Handle firmware reset status during IF_UP.")
Reviewed-by: default avatarKalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: default avatarAndy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: default avatarSreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: default avatarMichael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20250825175927.459987-2-michael.chan@broadcom.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent d9b0ca13

drivers/net/ethernet/broadcom/bnxt/bnxt.c

+16 −5
Original line number Diff line number Diff line
@@ -12851,6 +12851,17 @@ static int bnxt_set_xps_mapping(struct bnxt *bp) 
	return rc;

}



static int bnxt_tx_nr_rings(struct bnxt *bp)

{

	return bp->num_tc ? bp->tx_nr_rings_per_tc * bp->num_tc :

			    bp->tx_nr_rings_per_tc;

}



static int bnxt_tx_nr_rings_per_tc(struct bnxt *bp)

{

	return bp->num_tc ? bp->tx_nr_rings / bp->num_tc : bp->tx_nr_rings;

}



static int __bnxt_open_nic(struct bnxt *bp, bool irq_re_init, bool link_re_init)

{

	int rc = 0;
@@ -16325,7 +16336,7 @@ static void bnxt_trim_dflt_sh_rings(struct bnxt *bp) 
	bp->cp_nr_rings = min_t(int, bp->tx_nr_rings_per_tc, bp->rx_nr_rings);

	bp->rx_nr_rings = bp->cp_nr_rings;

	bp->tx_nr_rings_per_tc = bp->cp_nr_rings;

	bp->tx_nr_rings = bp->tx_nr_rings_per_tc;

	bp->tx_nr_rings = bnxt_tx_nr_rings(bp);

}



static int bnxt_set_dflt_rings(struct bnxt *bp, bool sh)
@@ -16357,7 +16368,7 @@ static int bnxt_set_dflt_rings(struct bnxt *bp, bool sh) 
		bnxt_trim_dflt_sh_rings(bp);

	else

		bp->cp_nr_rings = bp->tx_nr_rings_per_tc + bp->rx_nr_rings;

	bp->tx_nr_rings = bp->tx_nr_rings_per_tc;

	bp->tx_nr_rings = bnxt_tx_nr_rings(bp);



	avail_msix = bnxt_get_max_func_irqs(bp) - bp->cp_nr_rings;

	if (avail_msix >= BNXT_MIN_ROCE_CP_RINGS) {
@@ -16370,7 +16381,7 @@ static int bnxt_set_dflt_rings(struct bnxt *bp, bool sh) 
	rc = __bnxt_reserve_rings(bp);

	if (rc && rc != -ENODEV)

		netdev_warn(bp->dev, "Unable to reserve tx rings\n");

	bp->tx_nr_rings_per_tc = bp->tx_nr_rings;

	bp->tx_nr_rings_per_tc = bnxt_tx_nr_rings_per_tc(bp);

	if (sh)

		bnxt_trim_dflt_sh_rings(bp);
@@ -16379,7 +16390,7 @@ static int bnxt_set_dflt_rings(struct bnxt *bp, bool sh) 
		rc = __bnxt_reserve_rings(bp);

		if (rc && rc != -ENODEV)

			netdev_warn(bp->dev, "2nd rings reservation failed.\n");

		bp->tx_nr_rings_per_tc = bp->tx_nr_rings;

		bp->tx_nr_rings_per_tc = bnxt_tx_nr_rings_per_tc(bp);

	}

	if (BNXT_CHIP_TYPE_NITRO_A0(bp)) {

		bp->rx_nr_rings++;
@@ -16413,7 +16424,7 @@ static int bnxt_init_dflt_ring_mode(struct bnxt *bp) 
	if (rc)

		goto init_dflt_ring_err;



	bp->tx_nr_rings_per_tc = bp->tx_nr_rings;

	bp->tx_nr_rings_per_tc = bnxt_tx_nr_rings_per_tc(bp);



	bnxt_set_dflt_rfs(bp);