CVE-2026-68135: net: hip04: fix RX buffer leak on build_skb failure

CVE-2026-68135: net: hip04: fix RX buffer leak on build_skb failure

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

net: hip04: fix RX buffer leak on build_skb failure

When build_skb() fails in hip04_rx_poll(), the driver jumps to the
refill path without releasing the current RX buffer and its DMA mapping.
Installing a replacement buffer then overwrites the slot references and
leaks both resources.

Keep the current slot intact and return budget so NAPI retries the same
buffer.  Also free a newly allocated RX fragment when dma_map_single()
fails.

This issue was found by an in-house static analysis tool.

The Linux kernel CVE team has assigned CVE-2026-68135 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 4.5 with commit 701a0fd5231866db08cebcd502894699f49cb960 and fixed in 6.6.148 with commit e054dcd990d8180cde529ea28ce0838e76a5ad5e
	Issue introduced in 4.5 with commit 701a0fd5231866db08cebcd502894699f49cb960 and fixed in 6.12.101 with commit 67a7614bde310da006ab259f4f163d3fb0f9e253
	Issue introduced in 4.5 with commit 701a0fd5231866db08cebcd502894699f49cb960 and fixed in 6.18.42 with commit 80d977f280b4eccd4ac5369871d0ecb2b9c9a49d
	Issue introduced in 4.5 with commit 701a0fd5231866db08cebcd502894699f49cb960 and fixed in 7.1.6 with commit a0f247d63489a107bbc3b712a77b302af2a2a173
	Issue introduced in 4.5 with commit 701a0fd5231866db08cebcd502894699f49cb960 and fixed in 7.2-rc5 with commit 14fa65d10f5696b063a7d8d26e8291ea84a2c6ed

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-68135
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/net/ethernet/hisilicon/hip04_eth.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/e054dcd990d8180cde529ea28ce0838e76a5ad5e
	https://git.kernel.org/stable/c/67a7614bde310da006ab259f4f163d3fb0f9e253
	https://git.kernel.org/stable/c/80d977f280b4eccd4ac5369871d0ecb2b9c9a49d
	https://git.kernel.org/stable/c/a0f247d63489a107bbc3b712a77b302af2a2a173
	https://git.kernel.org/stable/c/14fa65d10f5696b063a7d8d26e8291ea84a2c6ed