bnxt: fix crashes when reducing ring count with active RSS contexts

bnxt doesn't check if a ring is used by RSS contexts when reducing
ring count. Core performs a similar check for the drivers for
the main context, but core doesn't know about additional contexts,
so it can't validate them. bnxt_fill_hw_rss_tbl_p5() uses ring
id to index bp->rx_ring[], which without the check may end up
being out of bounds.

  BUG: KASAN: slab-out-of-bounds in __bnxt_hwrm_vnic_set_rss+0xb79/0xe40
  Read of size 2 at addr ffff8881c5809618 by task ethtool/31525
  Call Trace:
  __bnxt_hwrm_vnic_set_rss+0xb79/0xe40
   bnxt_hwrm_vnic_rss_cfg_p5+0xf7/0x460
   __bnxt_setup_vnic_p5+0x12e/0x270
   __bnxt_open_nic+0x2262/0x2f30
   bnxt_open_nic+0x5d/0xf0
   ethnl_set_channels+0x5d4/0xb30
   ethnl_default_set_doit+0x2f1/0x620

Core does track the additional contexts in net-next, so we can
move this validation out of the driver as a follow up there.

Fixes: b3d0083caf ("bnxt_en: Support RSS contexts in ethtool .{get|set}_rxfh()")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://patch.msgid.link/20240705020005.681746-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Jakub Kicinski 2024-07-04 19:00:05 -07:00 committed by Paolo Abeni
parent 30f747b8d5
commit 0d1b7d6c92
3 changed files with 22 additions and 0 deletions

View File

@ -6146,6 +6146,21 @@ static u16 bnxt_get_max_rss_ring(struct bnxt *bp)
return max_ring;
}
u16 bnxt_get_max_rss_ctx_ring(struct bnxt *bp)
{
u16 i, tbl_size, max_ring = 0;
struct bnxt_rss_ctx *rss_ctx;
tbl_size = bnxt_get_rxfh_indir_size(bp->dev);
list_for_each_entry(rss_ctx, &bp->rss_ctx_list, list) {
for (i = 0; i < tbl_size; i++)
max_ring = max(max_ring, rss_ctx->rss_indir_tbl[i]);
}
return max_ring;
}
int bnxt_get_nr_rss_ctxs(struct bnxt *bp, int rx_rings)
{
if (bp->flags & BNXT_FLAG_CHIP_P5_PLUS) {

View File

@ -2776,6 +2776,7 @@ int bnxt_hwrm_vnic_set_tpa(struct bnxt *bp, struct bnxt_vnic_info *vnic,
void bnxt_fill_ipv6_mask(__be32 mask[4]);
int bnxt_alloc_rss_indir_tbl(struct bnxt *bp, struct bnxt_rss_ctx *rss_ctx);
void bnxt_set_dflt_rss_indir_tbl(struct bnxt *bp, struct bnxt_rss_ctx *rss_ctx);
u16 bnxt_get_max_rss_ctx_ring(struct bnxt *bp);
int bnxt_get_nr_rss_ctxs(struct bnxt *bp, int rx_rings);
int bnxt_hwrm_vnic_cfg(struct bnxt *bp, struct bnxt_vnic_info *vnic);
int bnxt_hwrm_vnic_alloc(struct bnxt *bp, struct bnxt_vnic_info *vnic,

View File

@ -961,6 +961,12 @@ static int bnxt_set_channels(struct net_device *dev,
return rc;
}
if (req_rx_rings < bp->rx_nr_rings &&
req_rx_rings <= bnxt_get_max_rss_ctx_ring(bp)) {
netdev_warn(dev, "Can't deactivate rings used by RSS contexts\n");
return -EINVAL;
}
if (bnxt_get_nr_rss_ctxs(bp, req_rx_rings) !=
bnxt_get_nr_rss_ctxs(bp, bp->rx_nr_rings) &&
netif_is_rxfh_configured(dev)) {