Commit 2156a29a authored by Michael Bommarito's avatar Michael Bommarito Committed by Jakub Kicinski
Browse files

octeontx2-af: validate body pcifunc in rvu_mbox_handler_rep_event_notify 



rvu_mbox_handler_rep_event_notify() in drivers/net/ethernet/marvell/
octeontx2/af/rvu_rep.c queues a sender-controlled REP_EVENT_NOTIFY
request body verbatim, and rvu_rep_up_notify() then forwards
event->pcifunc (the nested body field, distinct from the
AF-normalised header pcifunc) into rvu_get_pfvf(), rvu_get_pf() and
the AF->PF mailbox device index without any bounds check.

A VF attached to a PF that has been put into switchdev
representor mode reaches this path: the VF mailbox handler
otx2_pfvf_mbox_handler() forwards every message id including
MBOX_MSG_REP_EVENT_NOTIFY to AF without an allowlist, and the AF
dispatcher rewrites only msg->pcifunc, leaving struct
rep_event::pcifunc attacker-controlled.  The sibling
rvu_mbox_handler_esw_cfg() refuses requests whose header pcifunc
is not rvu->rep_pcifunc; this handler has no equivalent gate.

An out-of-range body pcifunc selects an &rvu->pf[]/&rvu->hwvf[]
element past the allocated array and, for RVU_EVENT_MAC_ADDR_CHANGE,
turns into a six-byte attacker-chosen OOB ether_addr_copy() target
inside the queued worker; KASAN reports a slab-out-of-bounds write
in rvu_rep_wq_handler.

Reject malformed requests at the handler entry by gating on
is_pf_func_valid(), which is already the canonical PF/VF range check
in this driver; expose it via rvu.h so callers in rvu_rep.c can use
it instead of open-coding the same range arithmetic.

Fixes: b8fea84a ("octeontx2-pf: Add support to sync link state between representor and VFs")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarMichael Bommarito <michael.bommarito@gmail.com>
Link: https://patch.msgid.link/20260520154157.1439319-1-michael.bommarito@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e68842b3

drivers/net/ethernet/marvell/octeontx2/af/rvu.c

+1 −1
Original line number Diff line number Diff line
@@ -436,7 +436,7 @@ struct rvu_pfvf *rvu_get_pfvf(struct rvu *rvu, int pcifunc) 
		return &rvu->pf[rvu_get_pf(rvu->pdev, pcifunc)];

}



static bool is_pf_func_valid(struct rvu *rvu, u16 pcifunc)

bool is_pf_func_valid(struct rvu *rvu, u16 pcifunc)

{

	int pf, vf, nvfs;

	u64 cfg;

drivers/net/ethernet/marvell/octeontx2/af/rvu.h

+1 −0
Original line number Diff line number Diff line
@@ -917,6 +917,7 @@ u16 rvu_get_rsrc_mapcount(struct rvu_pfvf *pfvf, int blkaddr); 
struct rvu_pfvf *rvu_get_pfvf(struct rvu *rvu, int pcifunc);

void rvu_get_pf_numvfs(struct rvu *rvu, int pf, int *numvfs, int *hwvf);

bool is_block_implemented(struct rvu_hwinfo *hw, int blkaddr);

bool is_pf_func_valid(struct rvu *rvu, u16 pcifunc);

bool is_pffunc_map_valid(struct rvu *rvu, u16 pcifunc, int blktype);

int rvu_get_lf(struct rvu *rvu, struct rvu_block *block, u16 pcifunc, u16 slot);

int rvu_lf_reset(struct rvu *rvu, struct rvu_block *block, int lf);

drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c

+8 −0
Original line number Diff line number Diff line
@@ -97,6 +97,14 @@ int rvu_mbox_handler_rep_event_notify(struct rvu *rvu, struct rep_event *req, 
{

	struct rep_evtq_ent *qentry;



	/* The mailbox dispatcher normalises only the header pcifunc; the

	 * nested struct rep_event::pcifunc body field is sender-controlled

	 * and is later used by rvu_rep_up_notify() to index rvu->pf[] /

	 * rvu->hwvf[].  Reject out-of-range body selectors before queueing.

	 */

	if (!is_pf_func_valid(rvu, req->pcifunc))

		return -EINVAL;



	qentry = kmalloc_obj(*qentry, GFP_ATOMIC);

	if (!qentry)

		return -ENOMEM;