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Thu, 18 Jun 2026 16:22:48 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 8FF3D1gbNGqCDgAAD6G6ig (envelope-from ); Thu, 18 Jun 2026 16:22:48 +0000 From: Fernando Fernandez Mancera To: netdev@vger.kernel.org Cc: nicolas.dichtel@6wind.com, shemminger@vyatta.com, dforster@brocade.com, gospo@cumulusnetworks.com, ddutt@cumulusnetworks.com, brian.haley@hp.com, horms@kernel.org, pabeni@redhat.com, kuba@kernel.org, edumazet@google.com, davem@davemloft.net, idosch@nvidia.com, dsahern@kernel.org, Fernando Fernandez Mancera Subject: [PATCH net 5/6] ipv6: reset value and position for proxy_ndp sysctl restart Date: Thu, 18 Jun 2026 18:22:24 +0200 Message-ID: <20260618162225.4588-6-fmancera@suse.de> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260618162225.4588-1-fmancera@suse.de> References: <20260618162225.4588-1-fmancera@suse.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Action: no action X-Rspamd-Queue-Id: 292386D48F X-Spam-Flag: NO X-Spam-Score: -3.01 X-Spam-Level: X-Spamd-Result: default: False [-3.01 / 50.00]; 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Fix this by restoring the original value and position pointer before restarting the syscall. Fixes: c92d5491a6d9 ("netconf: add support for IPv6 proxy_ndp") Signed-off-by: Fernando Fernandez Mancera --- net/ipv6/addrconf.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 8ff015975e27..1cfb223476bd 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -6483,8 +6483,9 @@ static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos) { int *valp = ctl->data; - int ret; + loff_t pos = *ppos; int old, new; + int ret; old = *valp; ret = proc_dointvec(ctl, write, buffer, lenp, ppos); @@ -6493,8 +6494,12 @@ static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write, if (write && old != new) { struct net *net = ctl->extra2; - if (!rtnl_net_trylock(net)) + if (!rtnl_net_trylock(net)) { + /* Restore the original values before restarting */ + *valp = old; + *ppos = pos; return restart_syscall(); + } if (valp == &net->ipv6.devconf_dflt->proxy_ndp) { inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, -- 2.54.0