FAILED: patch "[PATCH] octeontx2-af: cn10k: restrict VF LMTLINE sharing to its own" failed to apply to 6.6-stable tree

The patch below does not apply to the 6.6-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-6.6.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 '2026072018-anatomy-splicing-366a@gregkh' --subject-prefix 'PATCH 6.6.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.c       | 2 +-
 drivers/net/ethernet/marvell/octeontx2/af/rvu.h       | 1 +
 drivers/net/ethernet/marvell/octeontx2/af/rvu_cn10k.c | 9 +++++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

index 760dca4d5bfcb8..09352941ae61dd 100644
@@ -440,7 +440,7 @@ struct rvu_pfvf *rvu_get_pfvf(struct rvu *rvu, int pcifunc)
 		return &rvu->pf[rvu_get_pf(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 11d25404d57166..f26814c4990286 100644
@@ -751,6 +751,7 @@ int rvu_get_pf(u16 pcifunc);
 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 1e4cd4f7d0cfd4..a76deef58af82c 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(req->hdr.pcifunc) !=
+		     rvu_get_pf(req->base_pcifunc)))
+			return -EPERM;
+
 		/* Calculating the LMT table index equivalent to primary
 		 * pcifunc.
 		 */

2.53.0