From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 4442F81F18 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org D0B0181A6D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1687343037; x=1689935037; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=qIP/RgUHzsZiGVBRB71b7glXbG7VXiyuTjWvBX5krQg=; b=S/CdoZua/1rLl8yRwjaUF9IfJ2JcWeppWIYsAe/kEWbp+VzSobUM4iS9eeLWZHt5FO j/+mECwtEut66NCJpjuzLpLobjA7fzCyDUwpVOGTHl1cVmF3qTtFzfRaBX7G+Tegl8Tm 87Q/OZiSy1hpcxgY+MGptzKzvpXBNnTUuiwawnXX2OiPypV+k03lx7aTLBlVlmFPyOCK oOwW0/iZyWnJ4lfaT24bKv+GYWW44GzHrflM4FjMvA3v2Bo8q5EMHhya2b4FnBXvqkic qrcQPaiA4BdDNTsbHtCocDQbJDuuggPiCViWJpmfQFFiYemQpuO3YqlziZ0eyW6vOYiK i8ZA== Date: Wed, 21 Jun 2023 13:23:52 +0300 From: Dan Carpenter Message-ID: <5aba7eee-7a6e-4f3b-9921-e4220d479346@kadam.mountain> References: <20230621091000.424843-1-j.granados@samsung.com> <20230621091000.424843-7-j.granados@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Bridge] [PATCH 06/11] sysctl: Add size to register_net_sysctl function List-Id: Linux Ethernet Bridging List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Joel Granados Cc: Alexander Aring , Nikolay Aleksandrov , Marcelo Ricardo Leitner , David Howells , Eric Dumazet , Miquel Raynal , Marc Dionne , Jan Karcher , Mat Martineau , linux-afs@lists.infradead.org, Stefan Schmidt , Steffen Klassert , linux-s390@vger.kernel.org, rds-devel@oss.oracle.com, Xin Long , Herbert Xu , Leon Romanovsky , dccp@vger.kernel.org, linux-rdma@vger.kernel.org, bridge@lists.linux-foundation.org, Jozsef Kadlecsik , lvs-devel@vger.kernel.org, Jason Gunthorpe , Julian Anastasov , coreteam@netfilter.org, Roopa Prabhu , Jakub Kicinski , Paolo Abeni , Pablo Neira Ayuso , Martin Schiller , Santosh Shilimkar , linux-sctp@vger.kernel.org, Wenjia Zhang , Simon Horman , Remi Denis-Courmont , linux-hams@vger.kernel.org, mptcp@lists.linux.dev, tipc-discussion@lists.sourceforge.net, linux-x25@vger.kernel.org, Neil Horman , netdev@vger.kernel.org, David Ahern , Florian Westphal , linux-kernel@vger.kernel.org, Ralf Baechle , Karsten Graul , Jon Maloy , mcgrof@kernel.org, netfilter-devel@vger.kernel.org, Joerg Reuter , Ying Xue , Matthieu Baerts , linux-wpan@vger.kernel.org, "David S. Miller" On Wed, Jun 21, 2023 at 12:47:30PM +0300, Dan Carpenter wrote: > The patchset doesn't include the actual interesting changes, just a > bunch of mechanical prep work. > > On Wed, Jun 21, 2023 at 11:09:55AM +0200, Joel Granados wrote: > > diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c > > index a91283d1e5bf..7b717434368c 100644 > > --- a/net/ieee802154/6lowpan/reassembly.c > > +++ b/net/ieee802154/6lowpan/reassembly.c > > @@ -379,7 +379,8 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) > > table[1].extra2 = &ieee802154_lowpan->fqdir->high_thresh; > > table[2].data = &ieee802154_lowpan->fqdir->timeout; > > > > - hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table); > > + hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table, > > + ARRAY_SIZE(lowpan_frags_ns_ctl_table)); > > For example, in lowpan_frags_ns_sysctl_register() the sentinel is > sometimes element zero if the user doesn't have enough permissions. I > would want to ensure that was handled correctly, but that's going to be > done later in a completely different patchset. I'm definitely not going > to remember to check. On reflecting the patch is obviously wrong. It should be pass zero as table_size in that case. See diff at the end. There is a similar bug in neigh_sysctl_register() where we use memset to zero out the whole table. And another in __ip_vs_lblc_init(). I used the smatch cross function database `smdb.py where ctl_table procname | grep '(null)' | grep min-max` to make a list of functions which set procname to zero. Probably we should add a WARN_ON() if procname is zero in the new code which doesn't use sentinels. regards, dan carpenter drivers/char/random.c | proc_do_uuid | (struct ctl_table)->procname | 0 fs/proc/proc_sysctl.c | new_dir | (struct ctl_table)->procname | 48,3906148897379000352 fs/proc/proc_sysctl.c | new_links | (struct ctl_table)->procname | 4096-ptr_max arch/arm64/kernel/fpsimd.c | vec_proc_do_default_vl | (struct ctl_table)->procname | 0 arch/arm64/kernel/armv8_deprecated.c | register_insn_emulation | (struct ctl_table)->procname | 0-u64max kernel/sysctl-test.c | sysctl_test_api_dointvec_null_tbl_data | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_api_dointvec_table_maxlen_unset | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_api_dointvec_table_len_is_zero | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_api_dointvec_table_read_but_position_set | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_dointvec_read_happy_single_positive | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_dointvec_read_happy_single_negative | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_dointvec_write_happy_single_positive | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_dointvec_write_happy_single_negative | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_api_dointvec_write_single_less_int_min | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl-test.c | sysctl_test_api_dointvec_write_single_greater_int_max | (struct ctl_table)->procname | 7612622206476333056 kernel/sysctl.c | proc_do_static_key | (struct ctl_table)->procname | 0 kernel/kexec_core.c | kexec_limit_handler | (struct ctl_table)->procname | 0 kernel/bpf/syscall.c | bpf_stats_handler | (struct ctl_table)->procname | 0 net/core/sysctl_net_core.c | rps_sock_flow_sysctl | (struct ctl_table)->procname | 0 net/core/sysctl_net_core.c | set_default_qdisc | (struct ctl_table)->procname | 0 net/core/neighbour.c | neigh_sysctl_register | (struct ctl_table)->procname | 0 net/netfilter/ipvs/ip_vs_lblc.c | __ip_vs_lblc_init | (struct ctl_table)->procname | 0-u64max net/netfilter/ipvs/ip_vs_lblcr.c | __ip_vs_lblcr_init | (struct ctl_table)->procname | 0-u64max net/netfilter/ipvs/ip_vs_ctl.c | proc_do_defense_mode | (struct ctl_table)->procname | 0 net/netfilter/ipvs/ip_vs_ctl.c | proc_do_sync_threshold | (struct ctl_table)->procname | 0 net/netfilter/ipvs/ip_vs_ctl.c | proc_do_sync_ports | (struct ctl_table)->procname | 0 net/netfilter/ipvs/ip_vs_ctl.c | ipvs_proc_est_nice | (struct ctl_table)->procname | 0 net/netfilter/ipvs/ip_vs_ctl.c | ipvs_proc_run_estimation | (struct ctl_table)->procname | 0 net/netfilter/ipvs/ip_vs_ctl.c | ip_vs_control_net_init_sysctl | (struct ctl_table)->procname | 0-u64max net/netfilter/nf_log.c | netfilter_log_sysctl_init | (struct ctl_table)->procname | 0-u64max net/sctp/sysctl.c | proc_sctp_do_hmac_alg | (struct ctl_table)->procname | 0 net/sctp/sysctl.c | proc_sctp_do_rto_min | (struct ctl_table)->procname | 0 net/sctp/sysctl.c | proc_sctp_do_rto_max | (struct ctl_table)->procname | 0 net/sctp/sysctl.c | proc_sctp_do_auth | (struct ctl_table)->procname | 0 net/sctp/sysctl.c | proc_sctp_do_udp_port | (struct ctl_table)->procname | 0 net/sctp/sysctl.c | proc_sctp_do_probe_interval | (struct ctl_table)->procname | 0 net/ipv6/route.c | ipv6_route_sysctl_init | (struct ctl_table)->procname | 0-u64max net/ipv6/addrconf.c | addrconf_sysctl_addr_gen_mode | (struct ctl_table)->procname | 0 net/ieee802154/6lowpan/reassembly.c | lowpan_frags_ns_sysctl_register | (struct ctl_table)->procname | 0-u64max net/xfrm/xfrm_sysctl.c | xfrm_sysctl_init | (struct ctl_table)->procname | 0-u64max net/phonet/sysctl.c | proc_local_port_range | (struct ctl_table)->procname | 0 net/ipv4/route.c | sysctl_route_net_init | (struct ctl_table)->procname | 0-u64max net/ipv4/sysctl_net_ipv4.c | ipv4_local_port_range | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | ipv4_privileged_ports | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | ipv4_ping_group_range | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_tcp_congestion_control | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_tcp_available_congestion_control | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_allowed_congestion_control | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_tcp_fastopen_key | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_tcp_available_ulp | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_tcp_ehash_entries | (struct ctl_table)->procname | 0 net/ipv4/sysctl_net_ipv4.c | proc_udp_hash_entries | (struct ctl_table)->procname | 0 diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c index a91283d1e5bf..749238d38014 100644 --- a/net/ieee802154/6lowpan/reassembly.c +++ b/net/ieee802154/6lowpan/reassembly.c @@ -360,6 +360,7 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) struct ctl_table_header *hdr; struct netns_ieee802154_lowpan *ieee802154_lowpan = net_ieee802154_lowpan(net); + size_t table_size = ARRAY_SIZE(lowpan_frags_ns_ctl_table); table = lowpan_frags_ns_ctl_table; if (!net_eq(net, &init_net)) { @@ -369,8 +370,10 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) goto err_alloc; /* Don't export sysctls to unprivileged users */ - if (net->user_ns != &init_user_ns) + if (net->user_ns != &init_user_ns) { table[0].procname = NULL; + table_size = 0; + } } table[0].data = &ieee802154_lowpan->fqdir->high_thresh; @@ -379,7 +382,7 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) table[1].extra2 = &ieee802154_lowpan->fqdir->high_thresh; table[2].data = &ieee802154_lowpan->fqdir->timeout; - hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table); + hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table, table_size); if (hdr == NULL) goto err_reg;