FAILED: patch "[PATCH] net: mctp: fix don't require received header reserved bits to" failed to apply to 6.12-stable tree
[email protected]
maintainerThe patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x a663bac71a2f0b3ac6c373168ca57b2a6e6381aa
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026050122-herring-charting-9169@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a663bac71a2f0b3ac6c373168ca57b2a6e6381aa Mon Sep 17 00:00:00 2001
From: Yuan Zhaoming <[email protected]>
Date: Fri, 17 Apr 2026 22:13:40 +0800
Subject: [PATCH] net: mctp: fix don't require received header reserved bits to
be zero
From the MCTP Base specification (DSP0236 v1.2.1), the first byte of the MCTP header contains a 4 bit reserved field, and 4 bit version.
On our current receive path, we require those 4 reserved bits to be zero, but the 9500-8i card is non-conformant, and may set these reserved bits.
DSP0236 states that the reserved bits must be written as zero, and ignored when read. While the device might not conform to the former, we should accept these message to conform to the latter.
Relax our check on the MCTP version byte to allow non-zero bits in the reserved field.
include/net/mctp.h +3 -0
@@ -26,6 +26,9 @@ struct mctp_hdr {#define MCTP_VER_MIN 1#define MCTP_VER_MAX 1 +/* Definitions for ver field */ +#define MCTP_HDR_VER_MASK GENMASK(3, 0) +/* Definitions for flags_seq_tag field */ #define MCTP_HDR_FLAG_SOM BIT(7)#define MCTP_HDR_FLAG_EOM BIT(6)
net/mctp/route.c +6 -2
@@ -441,6 +441,7 @@ static int mctp_dst_input(struct mctp_dst *dst, struct sk_buff *skb)unsigned long f;u8 tag, flags;int rc; +u8 ver; msk =NULL ; rc = -EINVAL ;
@@ -467,7 +468,8 @@ static int mctp_dst_input(struct mctp_dst *dst, struct sk_buff *skb) netid =mctp_cb (skb)->net;skb_pull (skb,sizeof (struct mctp_hdr )); -if (mh->ver !=1 ) + ver = mh->ver &MCTP_HDR_VER_MASK ; +if (ver <MCTP_VER_MIN || ver >MCTP_VER_MAX ) goto out; flags = mh->flags_seq_tag & (MCTP_HDR_FLAG_SOM |MCTP_HDR_FLAG_EOM );
@@ -1317,6 +1319,7 @@ static int mctp_pkttype_receive(struct sk_buff *skb, struct net_device *dev,struct mctp_dst dst;struct mctp_hdr *mh;int rc; +u8 ver;rcu_read_lock (); mdev =__mctp_dev_get (dev);
@@ -1334,7 +1337,8 @@ static int mctp_pkttype_receive(struct sk_buff *skb, struct net_device *dev,/* We have enough for a header; decode and route */ mh =mctp_hdr (skb); -if (mh->ver <MCTP_VER_MIN || mh->ver >MCTP_VER_MAX ) + ver = mh->ver &MCTP_HDR_VER_MASK ; +if (ver <MCTP_VER_MIN || ver >MCTP_VER_MAX ) goto err_drop;/* source must be valid unicast or null; drop reserved ranges and
Sasha Levin
maintainerPATCH 1/1 net: mctp: fix don't require received header reserved bits to be zero
From: Yuan Zhaoming <[email protected]>
[ Upstream commit a663bac71a2f0b3ac6c373168ca57b2a6e6381aa ]
From the MCTP Base specification (DSP0236 v1.2.1), the first byte of the MCTP header contains a 4 bit reserved field, and 4 bit version.
On our current receive path, we require those 4 reserved bits to be zero, but the 9500-8i card is non-conformant, and may set these reserved bits.
DSP0236 states that the reserved bits must be written as zero, and ignored when read. While the device might not conform to the former, we should accept these message to conform to the latter.
Relax our check on the MCTP version byte to allow non-zero bits in the reserved field.
--- include/net/mctp.h | 3 +++ net/mctp/route.c | 8 ++++++-- 2 files changed, 9 insertions(+), 2 deletions(-)
include/net/mctp.h +3 -0
@@ -26,6 +26,9 @@ struct mctp_hdr {#define MCTP_VER_MIN 1#define MCTP_VER_MAX 1 +/* Definitions for ver field */ +#define MCTP_HDR_VER_MASK GENMASK(3, 0) +/* Definitions for flags_seq_tag field */ #define MCTP_HDR_FLAG_SOM BIT(7)#define MCTP_HDR_FLAG_EOM BIT(6)
net/mctp/route.c +6 -2
@@ -388,6 +388,7 @@ static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb)unsigned long f;u8 tag, flags;int rc; +u8 ver; msk =NULL ; rc = -EINVAL ;
@@ -411,7 +412,8 @@ static int mctp_route_input(struct mctp_route *route, struct sk_buff *skb) netid =mctp_cb (skb)->net;skb_pull (skb,sizeof (struct mctp_hdr )); -if (mh->ver !=1 ) + ver = mh->ver &MCTP_HDR_VER_MASK ; +if (ver <MCTP_VER_MIN || ver >MCTP_VER_MAX ) goto out; flags = mh->flags_seq_tag & (MCTP_HDR_FLAG_SOM |MCTP_HDR_FLAG_EOM );
@@ -1197,6 +1199,7 @@ static int mctp_pkttype_receive(struct sk_buff *skb, struct net_device *dev,struct mctp_skb_cb *cb;struct mctp_route *rt;struct mctp_hdr *mh; +u8 ver;rcu_read_lock (); mdev =__mctp_dev_get (dev);
@@ -1214,7 +1217,8 @@ static int mctp_pkttype_receive(struct sk_buff *skb, struct net_device *dev,/* We have enough for a header; decode and route */ mh =mctp_hdr (skb); -if (mh->ver <MCTP_VER_MIN || mh->ver >MCTP_VER_MAX ) + ver = mh->ver &MCTP_HDR_VER_MASK ; +if (ver <MCTP_VER_MIN || ver >MCTP_VER_MAX ) goto err_drop;/* source must be valid unicast or null; drop reserved ranges and
Signature · 1 line
2.53.0