From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793692842; b=04tfi/HirlCmlp4hj6k0CdcyeyPBanz7gGLFhf+TtockgfP/aOr22IczgK3sZR0r1hH4 FpsmCtogt6EQ5tInWUQDsOaOCbT4+xo1VY5gPL3YbJwqSAnW+OJtxGs6FWLrvT4O360uy vWP1p7Cz6ok1QUI3A0Blg2feGrBK3eFeNS+K//UfucjJwZb/ZM9DMFq70wsRAN7Dt6Vd2 gFFRQ1ZnuAGPO4oFRMqsYPBXZaqyo6Q/Yk7LzgZNTBHglLAeNWge7zCNc2VZywtImEf9k udzHjWw7Ul6JJuh48S1ZxS91ELLXncaS2hgCdbFmLiiYyYDZOleDrOKs+Cxf5yFaRlA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793692842; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=o2eLsx/nGvouTivFiSiDQKL17S34wwlYhifrcocAVCA=; b=JBNsBo5H/JOv15vmSxF9hRINqoRcv4YqCGON8JeXIOJBLz9kI/LOgU5MWfabLkcDwPfF 1Ro/k2iZNcID0gDHPpEsWY6opKjEjZgUzETrUkvOgn2LnNpC8ccu34VMij2VcdOOAN/Ef xNhwKQoj6ACVuGtIUR61sZhoSElDrivsenm88vfs5DlxD4K2Lojtavhi9ETh29DUPXICL MrIOoqmIgBV3Ep/UnHUh+Cm29o5VKd0OCxhQwXd9U7PNvyVpI/ZBNQlUUXkoE5KEE6wwF 0nzu/hJHgIqj4d/IE4n8UJLZInLmAwV3Oxa1dkCBhcYEmYYX7L7EW+m/5uF7HTKirKg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=g9in8RL5; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 05870606A324; Tue, 3 Nov 2026 08:00:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=g9in8RL5 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 03EA31F0093A; Tue, 3 Nov 2026 08:00:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793692841; bh=o2eLsx/nGvouTivFiSiDQKL17S34wwlYhifrcocAVCA=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=g9in8RL56728oCnq6IV1kW+ddzlj4UsjLU4X6ShtIkiT2A5P6x7jvMcWBvRmWiQbx lTwHxTIr4GM2WexHy96Tc9t5+6AeFgQL/O1J/EPKo1K6Ppj+nfEPZkrom7LpXckGJk mAPGT7JzlRDLJT8bu3ngfPMcIlAno5MBOxrBkmHYI/ivJCZjHSZN/6+SLsgUSRYu7w 4G6wuW2C/mqHMmdF548D9FaaFVDXKjoSfYb1o81hnDcDHjYEPUKwiWAr6pGGsq1BbW d3AkGCxgP5BggMhR43Q6OJ2mOmDilWS5gy+9ta5yLCMMTDrGSMMOLY/63ZNT2dOunk xDHwsIzVuUZ2g== Date: Tue, 3 Nov 2026 09:00:18 +0100 From: Joel Granados To: Jiayuan Chen Cc: netdev@vger.kernel.org, stable@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , Randy Dunlap , David Ahern , Ido Schimmel , Thomas Gleixner , Petr Pavlu , Kuniyuki Iwashima , Fernando Fernandez Mancera , Willem de Bruijn , Maoyi Xie , Gerd Rausch , Zhan Xusheng , Oleg Nesterov , Chia-Yu Chang , Yung Chih Su , Wyatt Feng , Hannes Frederic Sowa , Flavio Leitner , Petr Mladek , "Paul E. McKenney" , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net v2 5/5] net: restrict message_cost and message_burst to non-negative values Message-ID: References: <20261027104701.296240-1-jiayuan.chen@linux.dev> <20261027104701.296240-6-jiayuan.chen@linux.dev> X-Mailing-List: netdev@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="kbkkqf6zqumhyeya" Content-Disposition: inline In-Reply-To: <20261027104701.296240-6-jiayuan.chen@linux.dev> --kbkkqf6zqumhyeya Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH net v2 5/5] net: restrict message_cost and message_burst to non-negative values MIME-Version: 1.0 On Tue, Oct 27, 2026 at 06:45:33PM +0800, Jiayuan Chen wrote: > net.core.message_cost and net.core.message_burst feed the interval and > burst of net_ratelimit_state, but neither rejects negative values: > message_burst uses plain proc_dointvec, and message_cost uses > proc_dointvec_jiffies, which happily stores -1 second as -HZ jiffies. >=20 > Since commit a940d145cc38 ("ratelimit: Warn if ->interval or ->burst are > negative"), ___ratelimit() splats on such values, so the next > net_ratelimit() caller warns, e.g. a martian source log: >=20 > Negative interval (-250) or burst (10): Uninitialized ratelimit_state s= tructure? > WARNING: lib/ratelimit.c:43 at ___ratelimit+0x56e/0x960, CPU#1: ping/32= 18 > RIP: 0010:___ratelimit+0x578/0x960 > Call Trace: > > net_ratelimit+0x1c/0x30 > ip_handle_martian_source+0x1bb/0x340 > ip_route_input_slow+0x1057/0x3650 > ip_route_input_noref+0x104/0x260 > arp_process+0x109b/0x2510 > arp_rcv+0x381/0x460 > __netif_receive_skb_one_core+0x173/0x1c0 > __netif_receive_skb+0x21/0x150 > process_backlog+0x37e/0x1200 > __napi_poll.constprop.0+0xa5/0x5e0 > net_rx_action+0x4c0/0xf70 > handle_softirqs+0x204/0x9b0 > __do_softirq+0x10/0x18 > do_softirq.part.0+0x49/0xd0 > >=20 > Negative values never meant anything here: 0 already expresses both > "no limit" (interval) and "suppress everything" (burst). >=20 > Reject them at write time. message_burst can simply use > proc_dointvec_minmax with extra1 =3D 0. proc_dointvec_jiffies has no > minmax variant, so add proc_dointvec_jiffies_minmax(), mirroring > proc_dointvec_ms_jiffies_minmax(), and use it for message_cost with > extra1 =3D 0. Note that like the ms variant, extra1/extra2 are compared > against the converted jiffies value. >=20 > Fixes: a940d145cc38 ("ratelimit: Warn if ->interval or ->burst are negati= ve") > Cc: stable@vger.kernel.org > Suggested-by: Joel Granados > Signed-off-by: Jiayuan Chen > --- > include/linux/jiffies.h | 2 ++ > kernel/time/jiffies.c | 40 ++++++++++++++++++++++++++++++++++++++ > net/core/sysctl_net_core.c | 6 ++++-- > 3 files changed, 46 insertions(+), 2 deletions(-) >=20 > diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h > index bbd57061802cd..de12920f8e94b 100644 > --- a/include/linux/jiffies.h > +++ b/include/linux/jiffies.h > @@ -646,6 +646,8 @@ extern unsigned long nsecs_to_jiffies(u64 n); > struct ctl_table; > int proc_dointvec_jiffies(const struct ctl_table *table, int dir, void *= buffer, > size_t *lenp, loff_t *ppos); > +int proc_dointvec_jiffies_minmax(const struct ctl_table *table, int dir, > + void *buffer, size_t *lenp, loff_t *ppos); > int proc_dointvec_ms_jiffies_minmax(const struct ctl_table *table, int d= ir, > void *buffer, size_t *lenp, loff_t *ppos); > int proc_dointvec_userhz_jiffies(const struct ctl_table *table, int dir, > diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c > index 9b3487d40cd6a..22a70caa58bc1 100644 > --- a/kernel/time/jiffies.c > +++ b/kernel/time/jiffies.c > @@ -165,6 +165,14 @@ static int do_proc_int_conv_jiffies(bool *negp, ulon= g *u_ptr, int *k_ptr, > sysctl_u2k_int_conv_hz, sysctl_k2u_int_conv_hz); > } > =20 > +static int do_proc_int_conv_jiffies_minmax(bool *negp, ulong *u_ptr, > + int *k_ptr, int dir, > + const struct ctl_table *tbl) > +{ > + return proc_int_conv(negp, u_ptr, k_ptr, dir, tbl, true, > + sysctl_u2k_int_conv_hz, sysctl_k2u_int_conv_hz); > +} > + > static int do_proc_int_conv_userhz_jiffies(bool *negp, ulong *u_ptr, > int *k_ptr, int dir, > const struct ctl_table *tbl) > @@ -213,6 +221,13 @@ static int do_proc_int_conv_jiffies(bool *negp, ulon= g *u_ptr, int *k_ptr, > return -ENOSYS; > } > =20 > +static int do_proc_int_conv_jiffies_minmax(bool *negp, ulong *u_ptr, > + int *k_ptr, int dir, > + const struct ctl_table *tbl) > +{ > + return -ENOSYS; > +} > + > static int do_proc_int_conv_userhz_jiffies(bool *negp, ulong *u_ptr, > int *k_ptr, int dir, > const struct ctl_table *tbl) > @@ -263,6 +278,31 @@ int proc_dointvec_jiffies(const struct ctl_table *ta= ble, int dir, > } > EXPORT_SYMBOL(proc_dointvec_jiffies); > =20 > +/** > + * proc_dointvec_jiffies_minmax - read a vector of integers as seconds w= ith min/max values > + * @table: the sysctl table > + * @dir: %TRUE if this is a write to the sysctl file > + * @buffer: the user buffer > + * @lenp: the size of the user buffer > + * @ppos: file position > + * > + * Reads/writes up to table->maxlen/sizeof(unsigned int) integer > + * values from/to the user buffer, treated as an ASCII string. > + * The values read are assumed to be in seconds, and are converted into > + * jiffies. The converted values are checked against the optional > + * table->extra1 (min) and table->extra2 (max) bounds, in jiffies; > + * a value outside the range is rejected with -EINVAL. > + * > + * Returns 0 on success. > + */ > +int proc_dointvec_jiffies_minmax(const struct ctl_table *table, int dir, > + void *buffer, size_t *lenp, loff_t *ppos) > +{ > + return proc_dointvec_conv(table, dir, buffer, lenp, ppos, > + do_proc_int_conv_jiffies_minmax); > +} > +EXPORT_SYMBOL(proc_dointvec_jiffies_minmax); > + > /** > * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ= seconds > * @table: the sysctl table > diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c > index 473c162736d69..9226b96f2e89b 100644 > --- a/net/core/sysctl_net_core.c > +++ b/net/core/sysctl_net_core.c > @@ -544,14 +544,16 @@ static struct ctl_table net_core_table[] =3D { > .data =3D &net_ratelimit_state.interval, > .maxlen =3D sizeof(int), > .mode =3D 0644, > - .proc_handler =3D proc_dointvec_jiffies, > + .proc_handler =3D proc_dointvec_jiffies_minmax, > + .extra1 =3D SYSCTL_ZERO, > }, > { > .procname =3D "message_burst", > .data =3D &net_ratelimit_state.burst, > .maxlen =3D sizeof(int), > .mode =3D 0644, > - .proc_handler =3D proc_dointvec, > + .proc_handler =3D proc_dointvec_minmax, > + .extra1 =3D SYSCTL_ZERO, > }, > #ifdef CONFIG_RPS > { > --=20 > 2.43.0 >=20 This LGTM Reviewed-by: Joel Granados --kbkkqf6zqumhyeya Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQGzBAABCgAdFiEErkcJVyXmMSXOyyeQupfNUreWQU8FAmrplE4ACgkQupfNUreW QU881Qv5AWWfnF1Ruky22k2G+2H2n6RfLkGk4bmIwQ48pNsbbSOJ3eX5+d6C2Zoo cTcgld7pDj+xI1lXnhsQ7JUgZGdR+8SoyKEmDu1KfidRj7FQV0i8v+O21WpooNfk TBteqHekPHA4FR4z6C5Yr77irgnj9RbVuE5ouASXpv8YKJlqa8yxoVLxoKx1CnhS 5l0xxZ8eRmvKkQMyjenrGfQ1B4iftk/FKkHjIVyrV2aTpLrYER6oTLFIH3jrJ0By 07ZVpLDBLUB2wPiEOrVXocadkQr+JBZy9UYkepXhbR3lEaOMM9G+GJ8WUPAzOjFz V2pdeanVf+rZM77gGp3qZ2vAguDkRA5J9lKe5zxujLwrST6h9o5ZQ4oHOiupf0B+ 6+NZTCM8qUO/N7NteI17+4ITHFZkUSMKMpzwP2P0Hl2gaA+7NCeTBrPz2dytwE+P mxZThyFWIAjoLLiobdYbaszhykxESBfXe+PVQxKCku5EwoOOcgqdIpG6DTidSMNA P6P+KYOJ =ZL7G -----END PGP SIGNATURE----- --kbkkqf6zqumhyeya--