From ed3038158e7b58dcf966cb7ec4ae98d152a5b794 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 24 Mar 2021 18:11:55 -0700 Subject: [PATCH 1/6] ethtool: fec: fix typo in kdoc s/porte/the port/ Signed-off-by: Jakub Kicinski Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- include/uapi/linux/ethtool.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index cde753bb2093..1433d6278018 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h @@ -1378,7 +1378,7 @@ struct ethtool_per_queue_op { /** * struct ethtool_fecparam - Ethernet forward error correction(fec) parameters * @cmd: Command number = %ETHTOOL_GFECPARAM or %ETHTOOL_SFECPARAM - * @active_fec: FEC mode which is active on porte + * @active_fec: FEC mode which is active on the port * @fec: Bitmask of supported/configured FEC modes * @rsvd: Reserved for future extensions. i.e FEC bypass feature. * From 408386817a9d32c88c9ac528749e9999d0e3f6a1 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 24 Mar 2021 18:11:56 -0700 Subject: [PATCH 2/6] ethtool: fec: remove long structure description Digging through the mailing list archive @autoneg was part of the first version of the RFC, this left over comment was pointed out twice in review but wasn't removed. The sentence is an exact copy-paste from pauseparam. Signed-off-by: Jakub Kicinski Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- include/uapi/linux/ethtool.h | 4 ---- 1 file changed, 4 deletions(-) diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index 1433d6278018..36bf435d232c 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h @@ -1381,10 +1381,6 @@ struct ethtool_per_queue_op { * @active_fec: FEC mode which is active on the port * @fec: Bitmask of supported/configured FEC modes * @rsvd: Reserved for future extensions. i.e FEC bypass feature. - * - * Drivers should reject a non-zero setting of @autoneg when - * autoneogotiation is disabled (or not supported) for the link. - * */ struct ethtool_fecparam { __u32 cmd; From 240e114411e74d2ee8121643e0c67717eb7c6982 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 24 Mar 2021 18:11:57 -0700 Subject: [PATCH 3/6] ethtool: fec: sanitize ethtool_fecparam->reserved struct ethtool_fecparam::reserved is never looked at by the core. Make sure it's actually 0. Unfortunately we can't return an error because old ethtool doesn't zero-initialize the structure for SET. On GET we can be more verbose, there are no in tree (ab)users. Fix up the kdoc on the structure. Remove the mention of FEC bypass. Seems like a niche thing to configure in the first place. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- include/uapi/linux/ethtool.h | 2 +- net/ethtool/ioctl.c | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index 36bf435d232c..9e2682a67460 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h @@ -1380,7 +1380,7 @@ struct ethtool_per_queue_op { * @cmd: Command number = %ETHTOOL_GFECPARAM or %ETHTOOL_SFECPARAM * @active_fec: FEC mode which is active on the port * @fec: Bitmask of supported/configured FEC modes - * @rsvd: Reserved for future extensions. i.e FEC bypass feature. + * @reserved: Reserved for future extensions, ignore on GET, write 0 for SET. */ struct ethtool_fecparam { __u32 cmd; diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index 0788cc3b3114..be3549023d89 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -2568,6 +2568,9 @@ static int ethtool_get_fecparam(struct net_device *dev, void __user *useraddr) if (rc) return rc; + if (WARN_ON_ONCE(fecparam.reserved)) + fecparam.reserved = 0; + if (copy_to_user(useraddr, &fecparam, sizeof(fecparam))) return -EFAULT; return 0; @@ -2583,6 +2586,8 @@ static int ethtool_set_fecparam(struct net_device *dev, void __user *useraddr) if (copy_from_user(&fecparam, useraddr, sizeof(fecparam))) return -EFAULT; + fecparam.reserved = 0; + return dev->ethtool_ops->set_fecparam(dev, &fecparam); } From d3b37fc805d9ef697451730ebdfc7e35e6c2ace8 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 24 Mar 2021 18:11:58 -0700 Subject: [PATCH 4/6] ethtool: fec: sanitize ethtool_fecparam->active_fec struct ethtool_fecparam::active_fec is a GET-only field, all in-tree drivers correctly ignore it on SET. Clear the field on SET to avoid any confusion. Again, we can't reject non-zero now since ethtool user space does not zero-init the param correctly. Signed-off-by: Jakub Kicinski Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- include/uapi/linux/ethtool.h | 2 +- net/ethtool/ioctl.c | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index 9e2682a67460..517b68c5fcec 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h @@ -1378,7 +1378,7 @@ struct ethtool_per_queue_op { /** * struct ethtool_fecparam - Ethernet forward error correction(fec) parameters * @cmd: Command number = %ETHTOOL_GFECPARAM or %ETHTOOL_SFECPARAM - * @active_fec: FEC mode which is active on the port + * @active_fec: FEC mode which is active on the port, GET only. * @fec: Bitmask of supported/configured FEC modes * @reserved: Reserved for future extensions, ignore on GET, write 0 for SET. */ diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index be3549023d89..237ffe5440ef 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -2586,6 +2586,7 @@ static int ethtool_set_fecparam(struct net_device *dev, void __user *useraddr) if (copy_from_user(&fecparam, useraddr, sizeof(fecparam))) return -EFAULT; + fecparam.active_fec = 0; fecparam.reserved = 0; return dev->ethtool_ops->set_fecparam(dev, &fecparam); From 42ce127d98641f2cb19cd499b5b3beb472c7eff1 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 24 Mar 2021 18:11:59 -0700 Subject: [PATCH 5/6] ethtool: fec: sanitize ethtool_fecparam->fec Reject NONE on set, this mode means device does not support FEC so it's a little out of place in the set interface. This should be safe to do - user space ethtool does not allow the use of NONE on set. A few drivers treat it the same as OFF, but none use it instead of OFF. Similarly reject an empty FEC mask. The common user space tool will not send such requests and most drivers correctly reject it already. Signed-off-by: Jakub Kicinski Reported-by: kernel test robot Reported-by: Dan Carpenter Signed-off-by: David S. Miller --- net/ethtool/ioctl.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index 237ffe5440ef..8797533ddc4b 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -2586,6 +2586,9 @@ static int ethtool_set_fecparam(struct net_device *dev, void __user *useraddr) if (copy_from_user(&fecparam, useraddr, sizeof(fecparam))) return -EFAULT; + if (!fecparam.fec || fecparam.fec & ETHTOOL_FEC_NONE_BIT) + return -EINVAL; + fecparam.active_fec = 0; fecparam.reserved = 0; From 6dbf94b264e62641d521975d0eddbeef36bacf3c Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 24 Mar 2021 18:12:00 -0700 Subject: [PATCH 6/6] ethtool: clarify the ethtool FEC interface The definition of the FEC driver interface is quite unclear. Improve the documentation. This is based on current driver and user space code, as well as the discussions about the interface: RFC v1 (24 Oct 2016): https://lore.kernel.org/netdev/1477363849-36517-1-git-send-email-vidya@cumulusnetworks.com/ - this version has the autoneg field - no active_fec field - none vs off confusion is already present RFC v2 (10 Feb 2017): https://lore.kernel.org/netdev/1486727004-11316-1-git-send-email-vidya@cumulusnetworks.com/ - autoneg removed - active_fec added v1 (10 Feb 2017): https://lore.kernel.org/netdev/1486751311-42019-1-git-send-email-vidya@cumulusnetworks.com/ - no changes in the code v1 (24 Jun 2017): https://lore.kernel.org/netdev/1498331985-8525-1-git-send-email-roopa@cumulusnetworks.com/ - include in tree user v2 (27 Jul 2017): https://lore.kernel.org/netdev/1501199248-24695-1-git-send-email-roopa@cumulusnetworks.com/ Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- include/uapi/linux/ethtool.h | 37 +++++++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 7 deletions(-) diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index 517b68c5fcec..f6ef7d42c7a1 100644 --- a/include/uapi/linux/ethtool.h +++ b/include/uapi/linux/ethtool.h @@ -1376,11 +1376,29 @@ struct ethtool_per_queue_op { }; /** - * struct ethtool_fecparam - Ethernet forward error correction(fec) parameters + * struct ethtool_fecparam - Ethernet Forward Error Correction parameters * @cmd: Command number = %ETHTOOL_GFECPARAM or %ETHTOOL_SFECPARAM - * @active_fec: FEC mode which is active on the port, GET only. - * @fec: Bitmask of supported/configured FEC modes + * @active_fec: FEC mode which is active on the port, single bit set, GET only. + * @fec: Bitmask of configured FEC modes. * @reserved: Reserved for future extensions, ignore on GET, write 0 for SET. + * + * FEC modes supported by the device can be read via %ETHTOOL_GLINKSETTINGS. + * FEC settings are configured by link autonegotiation whenever it's enabled. + * With autoneg on %ETHTOOL_GFECPARAM can be used to read the current mode. + * + * When autoneg is disabled %ETHTOOL_SFECPARAM controls the FEC settings. + * It is recommended that drivers only accept a single bit set in @fec. + * When multiple bits are set in @fec drivers may pick mode in an implementation + * dependent way. Drivers should reject mixing %ETHTOOL_FEC_AUTO_BIT with other + * FEC modes, because it's unclear whether in this case other modes constrain + * AUTO or are independent choices. + * Drivers must reject SET requests if they support none of the requested modes. + * + * If device does not support FEC drivers may use %ETHTOOL_FEC_NONE instead + * of returning %EOPNOTSUPP from %ETHTOOL_GFECPARAM. + * + * See enum ethtool_fec_config_bits for definition of valid bits for both + * @fec and @active_fec. */ struct ethtool_fecparam { __u32 cmd; @@ -1392,11 +1410,16 @@ struct ethtool_fecparam { /** * enum ethtool_fec_config_bits - flags definition of ethtool_fec_configuration - * @ETHTOOL_FEC_NONE: FEC mode configuration is not supported - * @ETHTOOL_FEC_AUTO: Default/Best FEC mode provided by driver + * @ETHTOOL_FEC_NONE: FEC mode configuration is not supported. Should not + * be used together with other bits. GET only. + * @ETHTOOL_FEC_AUTO: Select default/best FEC mode automatically, usually based + * link mode and SFP parameters read from module's EEPROM. + * This bit does _not_ mean autonegotiation. * @ETHTOOL_FEC_OFF: No FEC Mode - * @ETHTOOL_FEC_RS: Reed-Solomon Forward Error Detection mode - * @ETHTOOL_FEC_BASER: Base-R/Reed-Solomon Forward Error Detection mode + * @ETHTOOL_FEC_RS: Reed-Solomon FEC Mode + * @ETHTOOL_FEC_BASER: Base-R/Reed-Solomon FEC Mode + * @ETHTOOL_FEC_LLRS: Low Latency Reed Solomon FEC Mode (25G/50G Ethernet + * Consortium) */ enum ethtool_fec_config_bits { ETHTOOL_FEC_NONE_BIT,