RE: [EXT] [PATCH net] octeontx2-af: Fix possible buffer overflow

[Subbaraya Sundeep Bhatta]

Hi,

>-----Original Message-----
>From: Elena Salomatkina <elena.salomatkina.cmc@xxxxxxxxx>
>Sent: Saturday, November 25, 2023 2:38 AM
>To: Sunil Kovvuri Goutham <sgoutham@xxxxxxxxxxx>
>Cc: Elena Salomatkina <elena.salomatkina.cmc@xxxxxxxxx>; Linu Cherian
><lcherian@xxxxxxxxxxx>; Geethasowjanya Akula <gakula@xxxxxxxxxxx>;
>Jerin Jacob Kollanukkaran <jerinj@xxxxxxxxxxx>; Hariprasad Kelam
><hkelam@xxxxxxxxxxx>; Subbaraya Sundeep Bhatta <sbhatta@xxxxxxxxxxx>;
>David S. Miller <davem@xxxxxxxxxxxxx>; Eric Dumazet
><edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo Abeni
><pabeni@xxxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; linux-
>kernel@xxxxxxxxxxxxxxx; lvc-project@xxxxxxxxxxxxxxxx; Simon Horman
><horms@xxxxxxxxxx>
>Subject: [EXT] [PATCH net] octeontx2-af: Fix possible buffer overflow
>
>----------------------------------------------------------------------
>A loop in rvu_mbox_handler_nix_bandprof_free() contains a break if (idx ==
>MAX_BANDPROF_PER_PFFUNC), but if idx may reach
>MAX_BANDPROF_PER_PFFUNC buffer '(*req->prof_idx)[layer]' overflow
>happens before that check.
>
>The patch moves the break to the
>beginning of the loop.
>
>Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
>Fixes: e8e095b3b370 ("octeontx2-af: cn10k: Bandwidth profiles config
>support").
>Signed-off-by: Elena Salomatkina <elena.salomatkina.cmc@xxxxxxxxx>
>Reviewed-by: Simon Horman <horms@xxxxxxxxxx>

Reviewed-by: Subbaraya Sundeep <sbhatta@xxxxxxxxxxx>

Thanks,
Sundeep

>---
> drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
>b/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
>index 23c2f2ed2fb8..c112c71ff576 100644
>--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
>+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
>@@ -5505,6 +5505,8 @@ int rvu_mbox_handler_nix_bandprof_free(struct
>rvu *rvu,
>
> 		ipolicer = &nix_hw->ipolicer[layer];
> 		for (idx = 0; idx < req->prof_count[layer]; idx++) {
>+			if (idx == MAX_BANDPROF_PER_PFFUNC)
>+				break;
> 			prof_idx = req->prof_idx[layer][idx];
> 			if (prof_idx >= ipolicer->band_prof.max ||
> 			    ipolicer->pfvf_map[prof_idx] != pcifunc) @@ -
>5518,8 +5520,6 @@ int rvu_mbox_handler_nix_bandprof_free(struct rvu
>*rvu,
> 			ipolicer->pfvf_map[prof_idx] = 0x00;
> 			ipolicer->match_id[prof_idx] = 0;
> 			rvu_free_rsrc(&ipolicer->band_prof, prof_idx);
>-			if (idx == MAX_BANDPROF_PER_PFFUNC)
>-				break;
> 		}
> 	}
> 	mutex_unlock(&rvu->rsrc_lock);
>--
>2.34.1