[OE-core][wrynose][PATCH v2] u-boot: fix CVE-2026-29009

[Roopa Kalmath <Roopa.Kalmath@windriver.com>]

nfs_readlink_reply() validates rlen only against the incoming packet
length (inherited from CVE-2019-14195), but not against the destination
buffer nfs_path_buff[2048]. A malicious NFS server can send a valid
READLINK reply where pathlen + rlen exceeds sizeof(nfs_path_buff),
overflowing the BSS buffer into adjacent memory.

Reference:
[https://nvd.nist.gov/vuln/detail/cve-2026-29009]
[https://www.cve.org/CVERecord?id=CVE-2026-29009]

Backport the patch to fix CVE-2026-29009:
[https://git.u-boot-project.org/u-boot/u-boot/-/commit/d6694018eaddefac6aae974f9cec72fd6e58f1bc]

Signed-off-by: Roopa Kalmath <Roopa.Kalmath@windriver.com>
---
 .../u-boot/files/CVE-2026-29009.patch         | 38 +++++++++++++++++++
 meta/recipes-bsp/u-boot/u-boot_2026.01.bb     |  4 +-
 2 files changed, 41 insertions(+), 1 deletion(-)
 create mode 100644 meta/recipes-bsp/u-boot/files/CVE-2026-29009.patch

diff --git a/meta/recipes-bsp/u-boot/files/CVE-2026-29009.patch b/meta/recipes-bsp/u-boot/files/CVE-2026-29009.patch
new file mode 100644
index 0000000000..860e504414
--- /dev/null
+++ b/meta/recipes-bsp/u-boot/files/CVE-2026-29009.patch
@@ -0,0 +1,38 @@
+From 2b88f08722584cf235f7dacaa190af3d24deb40f Mon Sep 17 00:00:00 2001
+From: Roopa Kalmath <Roopa.Kalmath@windriver.com>
+Date: Fri, 9 Oct 2026 08:38:23 +0000
+Subject: [PATCH] u-boot:Fix CVE-2026-29009
+
+CVE: CVE-2026-29009
+
+Upstream-Status: Backport [https://git.u-boot-project.org/u-boot/u-boot/-/commit/d6694018eaddefac6aae974f9cec72fd6e58f1bc]
+
+Fixes: cf3a4f1e86 ("net: nfs: Fix CVE-2019-14195")
+Cc: stable@vger.kernel.org
+Signed-off-by: Sebastian Alba Vives <sebasjosue84@gmail.com>
+Reviewed-by: Jerome Forissier <jerome.forissier@arm.com>
+Signed-off-by: Roopa Kalmath <Roopa.Kalmath@windriver.com>
+---
+ net/nfs.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/net/nfs.c b/net/nfs.c
+index 537d4c62..9b628ecf 100644
+--- a/net/nfs.c
++++ b/net/nfs.c
+@@ -698,11 +698,15 @@ static int nfs_readlink_reply(uchar *pkt, unsigned len)
+ 
+ 		strcat(nfs_path, "/");
+ 		pathlen = strlen(nfs_path);
++		if (pathlen + rlen >= sizeof(nfs_path_buff))
++			return -NFS_RPC_DROP;
+ 		memcpy(nfs_path + pathlen,
+ 		       (uchar *)&(rpc_pkt.u.reply.data[2 + nfsv3_data_offset]),
+ 		       rlen);
+ 		nfs_path[pathlen + rlen] = 0;
+ 	} else {
++		if (rlen >= sizeof(nfs_path_buff))
++			return -NFS_RPC_DROP;
+ 		memcpy(nfs_path,
+ 		       (uchar *)&(rpc_pkt.u.reply.data[2 + nfsv3_data_offset]),
+ 		       rlen);
diff --git a/meta/recipes-bsp/u-boot/u-boot_2026.01.bb b/meta/recipes-bsp/u-boot/u-boot_2026.01.bb
index 9610d9e8fe..8dd15cf9cd 100644
--- a/meta/recipes-bsp/u-boot/u-boot_2026.01.bb
+++ b/meta/recipes-bsp/u-boot/u-boot_2026.01.bb
@@ -3,7 +3,9 @@ require u-boot.inc
 
 DEPENDS += "bc-native dtc-native gnutls-native python3-pyelftools-native"
 
-SRC_URI += "file://CVE-2026-46728.patch"
+SRC_URI += "file://CVE-2026-46728.patch \
+            file://CVE-2026-29009.patch \
+"
 
 CVE_STATUS[CVE-2026-33243] = "cpe-incorrect: NVD currently maps this CVE to denx:u-boot, but that mapping is incorrect for U-Boot; the U-Boot-side FIT issue is tracked separately as CVE-2026-46728 and is fixed by the included U-Boot backport."
 
-- 
2.49.1