From 65f9c4c5888913c2cf5d2fc9454c83f9930d537d Mon Sep 17 00:00:00 2001 From: Petr Oros Date: Fri, 24 Oct 2025 15:24:38 +0200 Subject: tools: ynl: fix string attribute length to include null terminator The ynl_attr_put_str() function was not including the null terminator in the attribute length calculation. This caused kernel to reject CTRL_CMD_GETFAMILY requests with EINVAL: "Attribute failed policy validation". For a 4-character family name like "dpll": - Sent: nla_len=8 (4 byte header + 4 byte string without null) - Expected: nla_len=9 (4 byte header + 5 byte string with null) The bug was introduced in commit 15d2540e0d62 ("tools: ynl: check for overflow of constructed messages") when refactoring from stpcpy() to strlen(). The original code correctly included the null terminator: end = stpcpy(ynl_attr_data(attr), str); attr->nla_len = NLA_HDRLEN + NLA_ALIGN(end - (char *)ynl_attr_data(attr)); Since stpcpy() returns a pointer past the null terminator, the length included it. The refactored version using strlen() omitted the +1. The fix also removes NLA_ALIGN() from nla_len calculation, since nla_len should contain actual attribute length, not aligned length. Alignment is only for calculating next attribute position. This makes the code consistent with ynl_attr_put(). CTRL_ATTR_FAMILY_NAME uses NLA_NUL_STRING policy which requires null terminator. Kernel validates with memchr() and rejects if not found. Fixes: 15d2540e0d62 ("tools: ynl: check for overflow of constructed messages") Signed-off-by: Petr Oros Tested-by: Ivan Vecera Reviewed-by: Ivan Vecera Link: https://lore.kernel.org/20251018151737.365485-3-zahari.doychev@linux.com Link: https://patch.msgid.link/20251024132438.351290-1-poros@redhat.com Signed-off-by: Jakub Kicinski --- tools/net/ynl/lib/ynl-priv.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'tools') diff --git a/tools/net/ynl/lib/ynl-priv.h b/tools/net/ynl/lib/ynl-priv.h index 29481989ea76..ced7dce44efb 100644 --- a/tools/net/ynl/lib/ynl-priv.h +++ b/tools/net/ynl/lib/ynl-priv.h @@ -313,7 +313,7 @@ ynl_attr_put_str(struct nlmsghdr *nlh, unsigned int attr_type, const char *str) struct nlattr *attr; size_t len; - len = strlen(str); + len = strlen(str) + 1; if (__ynl_attr_put_overflow(nlh, len)) return; @@ -321,7 +321,7 @@ ynl_attr_put_str(struct nlmsghdr *nlh, unsigned int attr_type, const char *str) attr->nla_type = attr_type; strcpy((char *)ynl_attr_data(attr), str); - attr->nla_len = NLA_HDRLEN + NLA_ALIGN(len); + attr->nla_len = NLA_HDRLEN + len; nlh->nlmsg_len += NLMSG_ALIGN(attr->nla_len); } -- cgit v1.2.3 From e3966940559d52aa1800a008dcfeec218dd31f88 Mon Sep 17 00:00:00 2001 From: Hangbin Liu Date: Fri, 24 Oct 2025 12:58:53 +0000 Subject: tools: ynl: avoid print_field when there is no reply When request a none support device operation, there will be no reply. In this case, the len(desc) check will always be true, causing print_field to enter an infinite loop and crash the program. Example reproducer: # ethtool.py -c veth0 To fix this, return immediately if there is no reply. Fixes: f3d07b02b2b8 ("tools: ynl: ethtool testing tool") Signed-off-by: Hangbin Liu Link: https://patch.msgid.link/20251024125853.102916-1-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski --- tools/net/ynl/pyynl/ethtool.py | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools') diff --git a/tools/net/ynl/pyynl/ethtool.py b/tools/net/ynl/pyynl/ethtool.py index 9b523cbb3568..fd0f6b8d54d1 100755 --- a/tools/net/ynl/pyynl/ethtool.py +++ b/tools/net/ynl/pyynl/ethtool.py @@ -44,6 +44,9 @@ def print_field(reply, *desc): Pretty-print a set of fields from the reply. desc specifies the fields and the optional type (bool/yn). """ + if not reply: + return + if len(desc) == 0: return print_field(reply, *zip(reply.keys(), reply.keys())) -- cgit v1.2.3 From 9311e9540a8b406d9f028aa87fb072a3819d4c82 Mon Sep 17 00:00:00 2001 From: Po-Hsu Lin Date: Mon, 27 Oct 2025 17:57:10 +0800 Subject: selftests: net: use BASH for bareudp testing In bareudp.sh, this script uses /bin/sh and it will load another lib.sh BASH script at the very beginning. But on some operating systems like Ubuntu, /bin/sh is actually pointed to DASH, thus it will try to run BASH commands with DASH and consequently leads to syntax issues: # ./bareudp.sh: 4: ./lib.sh: Bad substitution # ./bareudp.sh: 5: ./lib.sh: source: not found # ./bareudp.sh: 24: ./lib.sh: Syntax error: "(" unexpected Fix this by explicitly using BASH for bareudp.sh. This fixes test execution failures on systems where /bin/sh is not BASH. Reported-by: Edoardo Canepa Link: https://bugs.launchpad.net/bugs/2129812 Signed-off-by: Po-Hsu Lin Reviewed-by: Przemek Kitszel Link: https://patch.msgid.link/20251027095710.2036108-2-po-hsu.lin@canonical.com Signed-off-by: Jakub Kicinski --- tools/testing/selftests/net/bareudp.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/testing/selftests/net/bareudp.sh b/tools/testing/selftests/net/bareudp.sh index 4046131e7888..d9e5b967f815 100755 --- a/tools/testing/selftests/net/bareudp.sh +++ b/tools/testing/selftests/net/bareudp.sh @@ -1,4 +1,4 @@ -#!/bin/sh +#!/bin/bash # SPDX-License-Identifier: GPL-2.0 # Test various bareudp tunnel configurations. -- cgit v1.2.3