diff mbox series

net: sched: hfsc: dont intepret cls results when asked to drop

Message ID 20230915134408.3410595-1-make_ruc2021@163.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net: sched: hfsc: dont intepret cls results when asked to drop | expand

Checks

Context Check Description
netdev/series_format warning Single patches do not need cover letters; Target tree name not specified in the subject
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit fail Errors and warnings before: 1340 this patch: 1341
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang fail Errors and warnings before: 1363 this patch: 17
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn fail Errors and warnings before: 1363 this patch: 1364
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Ma Ke Sept. 15, 2023, 1:44 p.m. UTC 
If asked to drop a packet via TC_ACT_SHOT it is unsafe to
assume that res.class contains a valid pointer.

Signed-off-by: Ma Ke <make_ruc2021@163.com>
---
 net/sched/sch_hfsc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

kernel test robot Sept. 15, 2023, 4:27 p.m. UTC | #1 
Hi Ma,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]
[also build test WARNING on net/main linus/master v6.6-rc1 next-20230915]
[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/Ma-Ke/net-sched-hfsc-dont-intepret-cls-results-when-asked-to-drop/20230915-214635
base:   net-next/main
patch link:    https://lore.kernel.org/r/20230915134408.3410595-1-make_ruc2021%40163.com
patch subject: [PATCH] net: sched: hfsc: dont intepret cls results when asked to drop
config: m68k-allyesconfig (https://download.01.org/0day-ci/archive/20230916/202309160007.7615P5Df-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230916/202309160007.7615P5Df-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309160007.7615P5Df-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/compiler_types.h:80,
                    from <command-line>:
   net/sched/sch_hfsc.c: In function 'hfsc_classify':
>> include/linux/compiler_attributes.h:227:41: warning: attribute 'fallthrough' not preceding a case label or default label
     227 | # define fallthrough                    __attribute__((__fallthrough__))
         |                                         ^~~~~~~~~~~~~
   net/sched/sch_hfsc.c:1146:25: note: in expansion of macro 'fallthrough'
    1146 |                         fallthrough;
         |                         ^~~~~~~~~~~


vim +/fallthrough +227 include/linux/compiler_attributes.h

294f69e662d157 Joe Perches   2019-10-05  214  
294f69e662d157 Joe Perches   2019-10-05  215  /*
294f69e662d157 Joe Perches   2019-10-05  216   * Add the pseudo keyword 'fallthrough' so case statement blocks
294f69e662d157 Joe Perches   2019-10-05  217   * must end with any of these keywords:
294f69e662d157 Joe Perches   2019-10-05  218   *   break;
294f69e662d157 Joe Perches   2019-10-05  219   *   fallthrough;
ca0760e7d79e2b Wei Ming Chen 2021-05-06  220   *   continue;
294f69e662d157 Joe Perches   2019-10-05  221   *   goto <label>;
294f69e662d157 Joe Perches   2019-10-05  222   *   return [expression];
294f69e662d157 Joe Perches   2019-10-05  223   *
294f69e662d157 Joe Perches   2019-10-05  224   *  gcc: https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html#Statement-Attributes
294f69e662d157 Joe Perches   2019-10-05  225   */
294f69e662d157 Joe Perches   2019-10-05  226  #if __has_attribute(__fallthrough__)
294f69e662d157 Joe Perches   2019-10-05 @227  # define fallthrough                    __attribute__((__fallthrough__))
294f69e662d157 Joe Perches   2019-10-05  228  #else
294f69e662d157 Joe Perches   2019-10-05  229  # define fallthrough                    do {} while (0)  /* fallthrough */
a3f8a30f3f0079 Miguel Ojeda  2018-08-30  230  #endif
a3f8a30f3f0079 Miguel Ojeda  2018-08-30  231
kernel test robot Sept. 16, 2023, 12:03 p.m. UTC | #2 
Hi Ma,

kernel test robot noticed the following build errors:

[auto build test ERROR on net-next/main]
[also build test ERROR on net/main linus/master v6.6-rc1 next-20230915]
[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/Ma-Ke/net-sched-hfsc-dont-intepret-cls-results-when-asked-to-drop/20230915-214635
base:   net-next/main
patch link:    https://lore.kernel.org/r/20230915134408.3410595-1-make_ruc2021%40163.com
patch subject: [PATCH] net: sched: hfsc: dont intepret cls results when asked to drop
config: x86_64-rhel-8.3-rust (https://download.01.org/0day-ci/archive/20230916/202309161941.5lMYMKdM-lkp@intel.com/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230916/202309161941.5lMYMKdM-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309161941.5lMYMKdM-lkp@intel.com/

All errors (new ones prefixed by >>):

>> net/sched/sch_hfsc.c:1146:4: error: fallthrough annotation does not directly precede switch label
                           fallthrough;
                           ^
   include/linux/compiler_attributes.h:227:41: note: expanded from macro 'fallthrough'
   # define fallthrough                    __attribute__((__fallthrough__))
                                           ^
   1 error generated.


vim +1146 net/sched/sch_hfsc.c

^1da177e4c3f41 Linus Torvalds      2005-04-16  1119  
^1da177e4c3f41 Linus Torvalds      2005-04-16  1120  static struct hfsc_class *
^1da177e4c3f41 Linus Torvalds      2005-04-16  1121  hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
^1da177e4c3f41 Linus Torvalds      2005-04-16  1122  {
^1da177e4c3f41 Linus Torvalds      2005-04-16  1123  	struct hfsc_sched *q = qdisc_priv(sch);
a2f79227138c71 Patrick McHardy     2010-05-14  1124  	struct hfsc_class *head, *cl;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1125  	struct tcf_result res;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1126  	struct tcf_proto *tcf;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1127  	int result;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1128  
^1da177e4c3f41 Linus Torvalds      2005-04-16  1129  	if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
^1da177e4c3f41 Linus Torvalds      2005-04-16  1130  	    (cl = hfsc_find_class(skb->priority, sch)) != NULL)
^1da177e4c3f41 Linus Torvalds      2005-04-16  1131  		if (cl->level == 0)
^1da177e4c3f41 Linus Torvalds      2005-04-16  1132  			return cl;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1133  
c27f339af90bb8 Jarek Poplawski     2008-08-04  1134  	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
a2f79227138c71 Patrick McHardy     2010-05-14  1135  	head = &q->root;
25d8c0d55f241c John Fastabend      2014-09-12  1136  	tcf = rcu_dereference_bh(q->root.filter_list);
3aa2605594556c Davide Caratti      2021-07-28  1137  	while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) {
b633b393d00632 Ma Ke               2023-09-15  1138  		if (result == TC_ACT_SHOT)
b633b393d00632 Ma Ke               2023-09-15  1139  			return NULL;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1140  #ifdef CONFIG_NET_CLS_ACT
^1da177e4c3f41 Linus Torvalds      2005-04-16  1141  		switch (result) {
^1da177e4c3f41 Linus Torvalds      2005-04-16  1142  		case TC_ACT_QUEUED:
^1da177e4c3f41 Linus Torvalds      2005-04-16  1143  		case TC_ACT_STOLEN:
e25ea21ffa66a0 Jiri Pirko          2017-06-06  1144  		case TC_ACT_TRAP:
378a2f090f7a47 Jarek Poplawski     2008-08-04  1145  			*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
964201de695b8a Gustavo A. R. Silva 2020-07-07 @1146  			fallthrough;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1147  		}
^1da177e4c3f41 Linus Torvalds      2005-04-16  1148  #endif
cc7ec456f82da7 Eric Dumazet        2011-01-19  1149  		cl = (struct hfsc_class *)res.class;
cc7ec456f82da7 Eric Dumazet        2011-01-19  1150  		if (!cl) {
cc7ec456f82da7 Eric Dumazet        2011-01-19  1151  			cl = hfsc_find_class(res.classid, sch);
cc7ec456f82da7 Eric Dumazet        2011-01-19  1152  			if (!cl)
^1da177e4c3f41 Linus Torvalds      2005-04-16  1153  				break; /* filter selected invalid classid */
a2f79227138c71 Patrick McHardy     2010-05-14  1154  			if (cl->level >= head->level)
a2f79227138c71 Patrick McHardy     2010-05-14  1155  				break; /* filter may only point downwards */
^1da177e4c3f41 Linus Torvalds      2005-04-16  1156  		}
^1da177e4c3f41 Linus Torvalds      2005-04-16  1157  
^1da177e4c3f41 Linus Torvalds      2005-04-16  1158  		if (cl->level == 0)
^1da177e4c3f41 Linus Torvalds      2005-04-16  1159  			return cl; /* hit leaf class */
^1da177e4c3f41 Linus Torvalds      2005-04-16  1160  
^1da177e4c3f41 Linus Torvalds      2005-04-16  1161  		/* apply inner filter chain */
25d8c0d55f241c John Fastabend      2014-09-12  1162  		tcf = rcu_dereference_bh(cl->filter_list);
a2f79227138c71 Patrick McHardy     2010-05-14  1163  		head = cl;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1164  	}
^1da177e4c3f41 Linus Torvalds      2005-04-16  1165  
^1da177e4c3f41 Linus Torvalds      2005-04-16  1166  	/* classification failed, try default class */
^1da177e4c3f41 Linus Torvalds      2005-04-16  1167  	cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
^1da177e4c3f41 Linus Torvalds      2005-04-16  1168  	if (cl == NULL || cl->level > 0)
^1da177e4c3f41 Linus Torvalds      2005-04-16  1169  		return NULL;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1170  
^1da177e4c3f41 Linus Torvalds      2005-04-16  1171  	return cl;
^1da177e4c3f41 Linus Torvalds      2005-04-16  1172  }
^1da177e4c3f41 Linus Torvalds      2005-04-16  1173
diff mbox series

Patch

diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
index 3554085bc2be..8e07a215f7d1 100644
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1135,6 +1135,8 @@  hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 	head = &q->root;
 	tcf = rcu_dereference_bh(q->root.filter_list);
 	while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) {
+		if (result == TC_ACT_SHOT)
+			return NULL;
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
 		case TC_ACT_QUEUED:
@@ -1142,8 +1144,6 @@  hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 		case TC_ACT_TRAP:
 			*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
 			fallthrough;
-		case TC_ACT_SHOT:
-			return NULL;
 		}
 #endif
 		cl = (struct hfsc_class *)res.class;