FAILED: patch "[PATCH] octeontx2-af: cn10k: restrict VF LMTLINE sharing to its own" failed to apply to 6.18-stable tree

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 8cdcf3d2caacdee7ddd363705fb4d93b0c1a0915
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072017-removal-sequester-79b2@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8cdcf3d2caacdee7ddd363705fb4d93b0c1a0915 Mon Sep 17 00:00:00 2001
From: Junrui Luo <[email protected]>
Date: Mon, 15 Jun 2026 23:04:27 +0800
Subject: [PATCH] octeontx2-af: cn10k: restrict VF LMTLINE sharing to its own
PF

rvu_mbox_handler_lmtst_tbl_setup() uses req->base_pcifunc as a direct index into the LMT map table to read another function's LMTLINE physical base address and copy it into the caller's own LMT map table entry. The mailbox dispatcher authenticates req->hdr.pcifunc from the IRQ source, but req->base_pcifunc is a separate payload field and is not sanitized.

Reject the request with -EPERM when a VF caller's base_pcifunc is not a valid function under its own PF. is_pf_func_valid() bounds the FUNC field to the PF's configured VF count, keeping the computed index inside the caller's own slot block.

index d2163da28d18..fa4ea1258d29 100644
@@ -178,6 +178,15 @@ int rvu_mbox_handler_lmtst_tbl_setup(struct rvu *rvu,
 	 * pcifunc (will be the one who is calling this mailbox).
 	 */
 	if (req->base_pcifunc) {
+		/* A VF is untrusted and must not redirect its LMTLINE to
+		 * another PF's region, so confine VF callers to their own PF.
+		 */
+		if (is_vf(req->hdr.pcifunc) &&
+		    (!is_pf_func_valid(rvu, req->base_pcifunc) ||
+		     rvu_get_pf(rvu->pdev, req->hdr.pcifunc) !=
+		     rvu_get_pf(rvu->pdev, req->base_pcifunc)))
+			return -EPERM;
+
 		/* Calculating the LMT table index equivalent to primary
 		 * pcifunc.
 		 */

From: Junrui Luo <[email protected]>

[ Upstream commit 8cdcf3d2caacdee7ddd363705fb4d93b0c1a0915 ]

rvu_mbox_handler_lmtst_tbl_setup() uses req->base_pcifunc as a direct index into the LMT map table to read another function's LMTLINE physical base address and copy it into the caller's own LMT map table entry. The mailbox dispatcher authenticates req->hdr.pcifunc from the IRQ source, but req->base_pcifunc is a separate payload field and is not sanitized.

Reject the request with -EPERM when a VF caller's base_pcifunc is not a valid function under its own PF. is_pf_func_valid() bounds the FUNC field to the PF's configured VF count, keeping the computed index inside the caller's own slot block.

---
 drivers/net/ethernet/marvell/octeontx2/af/rvu_cn10k.c | 9 +++++++++
 1 file changed, 9 insertions(+)

index d2163da28d18f0..fa4ea1258d29d5 100644
@@ -178,6 +178,15 @@ int rvu_mbox_handler_lmtst_tbl_setup(struct rvu *rvu,
 	 * pcifunc (will be the one who is calling this mailbox).
 	 */
 	if (req->base_pcifunc) {
+		/* A VF is untrusted and must not redirect its LMTLINE to
+		 * another PF's region, so confine VF callers to their own PF.
+		 */
+		if (is_vf(req->hdr.pcifunc) &&
+		    (!is_pf_func_valid(rvu, req->base_pcifunc) ||
+		     rvu_get_pf(rvu->pdev, req->hdr.pcifunc) !=
+		     rvu_get_pf(rvu->pdev, req->base_pcifunc)))
+			return -EPERM;
+
 		/* Calculating the LMT table index equivalent to primary
 		 * pcifunc.
 		 */

2.53.0

From: Michael Bommarito <[email protected]>

[ Upstream commit 2156a29aecfffa2eb7c558255690084efbe9f3b0 ]

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.

Stable-dep-of: 8cdcf3d2caac ("octeontx2-af: cn10k: restrict VF LMTLINE sharing to its own PF")

---
 drivers/net/ethernet/marvell/octeontx2/af/rvu.c     | 2 +-
 drivers/net/ethernet/marvell/octeontx2/af/rvu.h     | 1 +
 drivers/net/ethernet/marvell/octeontx2/af/rvu_rep.c | 8 ++++++++
 3 files changed, 10 insertions(+), 1 deletion(-)

index ad733f4da3c185..019bd49015c603 100644
@@ -435,7 +435,7 @@ 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;

index 914ba2b691ec80..c9ed5276690d36 100644
@@ -900,6 +900,7 @@ 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);

index 4415d0ce9aef4e..d43c034b0264a6 100644
@@ -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(sizeof(*qentry), GFP_ATOMIC);
 	if (!qentry)
 		return -ENOMEM;

2.53.0