LinuxLists.cc - [PATCH] net: dccp: delete redundant ackvec record in dccp_insert

2023-02-21 09:22:29

Subject: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

A useless record can be insert into av_records when dccp_insert_options()
fails after dccp_insert_option_ackvec(). Repeated triggering may cause
av_records to have a lot of useless record with the same avr_ack_seqno.

Fixes: 8b7b6c75c638 ("dccp: Integrate feature-negotiation insertion code")
Signed-off-by: Hangyu Hua <[email protected]>
---
net/dccp/options.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/net/dccp/options.c b/net/dccp/options.c
index d24cad05001e..8aa4abeb15ea 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -549,6 +549,8 @@ static void dccp_insert_option_padding(struct sk_buff *skb)
int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
+ struct dccp_ackvec_record *avr;

DCCP_SKB_CB(skb)->dccpd_opt_len = 0;

@@ -577,16 +579,22 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)

if (dp->dccps_hc_rx_insert_options) {
if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
- return -1;
+ goto delete_ackvec;
dp->dccps_hc_rx_insert_options = 0;
}

if (dp->dccps_timestamp_echo != 0 &&
dccp_insert_option_timestamp_echo(dp, NULL, skb))
- return -1;
+ goto delete_ackvec;

dccp_insert_option_padding(skb);
return 0;
+
+delete_ackvec:
+ avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
+ list_del(&avr->avr_node);
+ kmem_cache_free(dccp_ackvec_record_slab, avr);
+ return -1;
}

int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
--
2.34.1

2023-02-21 12:47:13

by Eric Dumazet

[permalink] [raw]

Subject: Re: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

On Tue, Feb 21, 2023 at 10:22 AM Hangyu Hua <[email protected]> wrote:
>
> A useless record can be insert into av_records when dccp_insert_options()
> fails after dccp_insert_option_ackvec(). Repeated triggering may cause
> av_records to have a lot of useless record with the same avr_ack_seqno.
>
> Fixes: 8b7b6c75c638 ("dccp: Integrate feature-negotiation insertion code")
> Signed-off-by: Hangyu Hua <[email protected]>
> ---
> net/dccp/options.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/net/dccp/options.c b/net/dccp/options.c
> index d24cad05001e..8aa4abeb15ea 100644
> --- a/net/dccp/options.c
> +++ b/net/dccp/options.c
> @@ -549,6 +549,8 @@ static void dccp_insert_option_padding(struct sk_buff *skb)
> int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
> {
> struct dccp_sock *dp = dccp_sk(sk);
> + struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
> + struct dccp_ackvec_record *avr;
>
> DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
>
> @@ -577,16 +579,22 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
>
> if (dp->dccps_hc_rx_insert_options) {
> if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
> - return -1;
> + goto delete_ackvec;
> dp->dccps_hc_rx_insert_options = 0;
> }
>
> if (dp->dccps_timestamp_echo != 0 &&
> dccp_insert_option_timestamp_echo(dp, NULL, skb))
> - return -1;
> + goto delete_ackvec;
>
> dccp_insert_option_padding(skb);
> return 0;
> +
> +delete_ackvec:
> + avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);

Why avr would be not NULL ?

> + list_del(&avr->avr_node);
> + kmem_cache_free(dccp_ackvec_record_slab, avr);
> + return -1;
> }

Are you really using DCCP and/or how have you tested this patch ?

net/dccp/ackvec.c:15:static struct kmem_cache *dccp_ackvec_record_slab;

I doubt this patch has been compiled.

I would rather mark DCCP deprecated and stop trying to fix it.

2023-02-21 14:06:17

by kernel test robot

[permalink] [raw]

Subject: Re: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

Hi Hangyu,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]
[also build test WARNING on net/master horms-ipvs/master linus/master v6.2 next-20230221]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Hangyu-Hua/net-dccp-delete-redundant-ackvec-record-in-dccp_insert_options/20230221-172448
patch link: https://lore.kernel.org/r/20230221092206.39741-1-hbh25y%40gmail.com
patch subject: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()
config: ia64-allyesconfig (https://download.01.org/0day-ci/archive/20230221/[email protected]/config)
compiler: ia64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/ea44b55ba82bbe3f35b51212bf839f507a30b70b
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Hangyu-Hua/net-dccp-delete-redundant-ackvec-record-in-dccp_insert_options/20230221-172448
git checkout ea44b55ba82bbe3f35b51212bf839f507a30b70b
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash net/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

net/dccp/options.c: In function 'dccp_insert_options':
net/dccp/options.c:594:15: error: implicit declaration of function 'dccp_ackvec_lookup'; did you mean 'dccp_ackvec_input'? [-Werror=implicit-function-declaration]
594 | avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
| ^~~~~~~~~~~~~~~~~~
| dccp_ackvec_input
>> net/dccp/options.c:594:13: warning: assignment to 'struct dccp_ackvec_record *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
594 | avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
| ^
net/dccp/options.c:596:25: error: 'dccp_ackvec_record_slab' undeclared (first use in this function); did you mean 'dccp_ackvec_record'?
596 | kmem_cache_free(dccp_ackvec_record_slab, avr);
| ^~~~~~~~~~~~~~~~~~~~~~~
| dccp_ackvec_record
net/dccp/options.c:596:25: note: each undeclared identifier is reported only once for each function it appears in
cc1: some warnings being treated as errors

vim +594 net/dccp/options.c

548
549 int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
550 {
551 struct dccp_sock *dp = dccp_sk(sk);
552 struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
553 struct dccp_ackvec_record *avr;
554
555 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
556
557 if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
558 return -1;
559
560 if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
561
562 /* Feature Negotiation */
563 if (dccp_feat_insert_opts(dp, NULL, skb))
564 return -1;
565
566 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
567 /*
568 * Obtain RTT sample from Request/Response exchange.
569 * This is currently used for TFRC initialisation.
570 */
571 if (dccp_insert_option_timestamp(skb))
572 return -1;
573
574 } else if (dccp_ackvec_pending(sk) &&
575 dccp_insert_option_ackvec(sk, skb)) {
576 return -1;
577 }
578 }
579
580 if (dp->dccps_hc_rx_insert_options) {
581 if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
582 goto delete_ackvec;
583 dp->dccps_hc_rx_insert_options = 0;
584 }
585
586 if (dp->dccps_timestamp_echo != 0 &&
587 dccp_insert_option_timestamp_echo(dp, NULL, skb))
588 goto delete_ackvec;
589
590 dccp_insert_option_padding(skb);
591 return 0;
592
593 delete_ackvec:
> 594 avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
595 list_del(&avr->avr_node);
596 kmem_cache_free(dccp_ackvec_record_slab, avr);
597 return -1;
598 }
599

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

2023-02-21 14:36:25

by kernel test robot

[permalink] [raw]

Subject: Re: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

Hi Hangyu,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]
[also build test WARNING on net/master horms-ipvs/master linus/master v6.2 next-20230221]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Hangyu-Hua/net-dccp-delete-redundant-ackvec-record-in-dccp_insert_options/20230221-172448
patch link: https://lore.kernel.org/r/20230221092206.39741-1-hbh25y%40gmail.com
patch subject: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()
config: i386-randconfig-a013-20230220 (https://download.01.org/0day-ci/archive/20230221/[email protected]/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/ea44b55ba82bbe3f35b51212bf839f507a30b70b
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Hangyu-Hua/net-dccp-delete-redundant-ackvec-record-in-dccp_insert_options/20230221-172448
git checkout ea44b55ba82bbe3f35b51212bf839f507a30b70b
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash net/dccp/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

net/dccp/options.c:594:8: error: implicit declaration of function 'dccp_ackvec_lookup' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
^
>> net/dccp/options.c:594:6: warning: incompatible integer to pointer conversion assigning to 'struct dccp_ackvec_record *' from 'int' [-Wint-conversion]
avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/dccp/options.c:596:18: error: use of undeclared identifier 'dccp_ackvec_record_slab'; did you mean 'dccp_ackvec_clear_state'?
kmem_cache_free(dccp_ackvec_record_slab, avr);
^~~~~~~~~~~~~~~~~~~~~~~
dccp_ackvec_clear_state
net/dccp/ackvec.h:110:6: note: 'dccp_ackvec_clear_state' declared here
void dccp_ackvec_clear_state(struct dccp_ackvec *av, const u64 ackno);
^
1 warning and 2 errors generated.

vim +594 net/dccp/options.c

548
549 int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
550 {
551 struct dccp_sock *dp = dccp_sk(sk);
552 struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
553 struct dccp_ackvec_record *avr;
554
555 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
556
557 if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
558 return -1;
559
560 if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
561
562 /* Feature Negotiation */
563 if (dccp_feat_insert_opts(dp, NULL, skb))
564 return -1;
565
566 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
567 /*
568 * Obtain RTT sample from Request/Response exchange.
569 * This is currently used for TFRC initialisation.
570 */
571 if (dccp_insert_option_timestamp(skb))
572 return -1;
573
574 } else if (dccp_ackvec_pending(sk) &&
575 dccp_insert_option_ackvec(sk, skb)) {
576 return -1;
577 }
578 }
579
580 if (dp->dccps_hc_rx_insert_options) {
581 if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
582 goto delete_ackvec;
583 dp->dccps_hc_rx_insert_options = 0;
584 }
585
586 if (dp->dccps_timestamp_echo != 0 &&
587 dccp_insert_option_timestamp_echo(dp, NULL, skb))
588 goto delete_ackvec;
589
590 dccp_insert_option_padding(skb);
591 return 0;
592
593 delete_ackvec:
> 594 avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
595 list_del(&avr->avr_node);
596 kmem_cache_free(dccp_ackvec_record_slab, avr);
597 return -1;
598 }
599

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

2023-02-21 17:01:45

by kernel test robot

[permalink] [raw]

Subject: Re: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

2023-02-21 17:21:40

by kernel test robot

[permalink] [raw]

Subject: Re: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

Hi Hangyu,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on net-next/master]
[also build test ERROR on net/master horms-ipvs/master linus/master v6.2 next-20230221]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Hangyu-Hua/net-dccp-delete-redundant-ackvec-record-in-dccp_insert_options/20230221-172448
patch link: https://lore.kernel.org/r/20230221092206.39741-1-hbh25y%40gmail.com
patch subject: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()
config: s390-randconfig-r011-20230220 (https://download.01.org/0day-ci/archive/20230222/[email protected]/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project db89896bbbd2251fff457699635acbbedeead27f)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install s390 cross compiling tool for clang build
# apt-get install binutils-s390x-linux-gnu
# https://github.com/intel-lab-lkp/linux/commit/ea44b55ba82bbe3f35b51212bf839f507a30b70b
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Hangyu-Hua/net-dccp-delete-redundant-ackvec-record-in-dccp_insert_options/20230221-172448
git checkout ea44b55ba82bbe3f35b51212bf839f507a30b70b
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash net/dccp/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All errors (new ones prefixed by >>):

In file included from net/dccp/options.c:10:
In file included from include/linux/dccp.h:13:
In file included from include/net/inet_connection_sock.h:21:
In file included from include/net/inet_sock.h:19:
In file included from include/linux/netdevice.h:38:
In file included from include/net/net_namespace.h:43:
In file included from include/linux/skbuff.h:28:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
^
In file included from net/dccp/options.c:10:
In file included from include/linux/dccp.h:13:
In file included from include/net/inet_connection_sock.h:21:
In file included from include/net/inet_sock.h:19:
In file included from include/linux/netdevice.h:38:
In file included from include/net/net_namespace.h:43:
In file included from include/linux/skbuff.h:28:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
^
In file included from net/dccp/options.c:10:
In file included from include/linux/dccp.h:13:
In file included from include/net/inet_connection_sock.h:21:
In file included from include/net/inet_sock.h:19:
In file included from include/linux/netdevice.h:38:
In file included from include/net/net_namespace.h:43:
In file included from include/linux/skbuff.h:28:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
>> net/dccp/options.c:594:8: error: call to undeclared function 'dccp_ackvec_lookup'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
^
>> net/dccp/options.c:594:6: error: incompatible integer to pointer conversion assigning to 'struct dccp_ackvec_record *' from 'int' [-Wint-conversion]
avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> net/dccp/options.c:596:18: error: use of undeclared identifier 'dccp_ackvec_record_slab'; did you mean 'dccp_ackvec_clear_state'?
kmem_cache_free(dccp_ackvec_record_slab, avr);
^~~~~~~~~~~~~~~~~~~~~~~
dccp_ackvec_clear_state
net/dccp/ackvec.h:110:6: note: 'dccp_ackvec_clear_state' declared here
void dccp_ackvec_clear_state(struct dccp_ackvec *av, const u64 ackno);
^
12 warnings and 3 errors generated.

vim +/dccp_ackvec_lookup +594 net/dccp/options.c

548
549 int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
550 {
551 struct dccp_sock *dp = dccp_sk(sk);
552 struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
553 struct dccp_ackvec_record *avr;
554
555 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
556
557 if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
558 return -1;
559
560 if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
561
562 /* Feature Negotiation */
563 if (dccp_feat_insert_opts(dp, NULL, skb))
564 return -1;
565
566 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
567 /*
568 * Obtain RTT sample from Request/Response exchange.
569 * This is currently used for TFRC initialisation.
570 */
571 if (dccp_insert_option_timestamp(skb))
572 return -1;
573
574 } else if (dccp_ackvec_pending(sk) &&
575 dccp_insert_option_ackvec(sk, skb)) {
576 return -1;
577 }
578 }
579
580 if (dp->dccps_hc_rx_insert_options) {
581 if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
582 goto delete_ackvec;
583 dp->dccps_hc_rx_insert_options = 0;
584 }
585
586 if (dp->dccps_timestamp_echo != 0 &&
587 dccp_insert_option_timestamp_echo(dp, NULL, skb))
588 goto delete_ackvec;
589
590 dccp_insert_option_padding(skb);
591 return 0;
592
593 delete_ackvec:
> 594 avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
595 list_del(&avr->avr_node);
> 596 kmem_cache_free(dccp_ackvec_record_slab, avr);
597 return -1;
598 }
599

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

2023-02-22 02:13:01

by Hangyu Hua

[permalink] [raw]

Subject: Re: [PATCH] net: dccp: delete redundant ackvec record in dccp_insert_options()

On 21/2/2023 20:46, Eric Dumazet wrote:
> On Tue, Feb 21, 2023 at 10:22 AM Hangyu Hua <[email protected]> wrote:
>>
>> A useless record can be insert into av_records when dccp_insert_options()
>> fails after dccp_insert_option_ackvec(). Repeated triggering may cause
>> av_records to have a lot of useless record with the same avr_ack_seqno.
>>
>> Fixes: 8b7b6c75c638 ("dccp: Integrate feature-negotiation insertion code")
>> Signed-off-by: Hangyu Hua <[email protected]>
>> ---
>> net/dccp/options.c | 12 ++++++++++--
>> 1 file changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/net/dccp/options.c b/net/dccp/options.c
>> index d24cad05001e..8aa4abeb15ea 100644
>> --- a/net/dccp/options.c
>> +++ b/net/dccp/options.c
>> @@ -549,6 +549,8 @@ static void dccp_insert_option_padding(struct sk_buff *skb)
>> int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
>> {
>> struct dccp_sock *dp = dccp_sk(sk);
>> + struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
>> + struct dccp_ackvec_record *avr;
>>
>> DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
>>
>> @@ -577,16 +579,22 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
>>
>> if (dp->dccps_hc_rx_insert_options) {
>> if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
>> - return -1;
>> + goto delete_ackvec;
>> dp->dccps_hc_rx_insert_options = 0;
>> }
>>
>> if (dp->dccps_timestamp_echo != 0 &&
>> dccp_insert_option_timestamp_echo(dp, NULL, skb))
>> - return -1;
>> + goto delete_ackvec;
>>
>> dccp_insert_option_padding(skb);
>> return 0;
>> +
>> +delete_ackvec:
>> + avr = dccp_ackvec_lookup(&av->av_records, DCCP_SKB_CB(skb)->dccpd_seq);
>
> Why avr would be not NULL ?
>
>> + list_del(&avr->avr_node);
>> + kmem_cache_free(dccp_ackvec_record_slab, avr);
>> + return -1;
>> }
>
> Are you really using DCCP and/or how have you tested this patch ?
>
> net/dccp/ackvec.c:15:static struct kmem_cache *dccp_ackvec_record_slab;
>
> I doubt this patch has been compiled.
>
> I would rather mark DCCP deprecated and stop trying to fix it.

My bad. I will fix these problems.

Thanks,
Hangyu