Re: [PATCH] cgroup: Fix memory leak when parsing multiple source parameters

From: kernel test robot
Date: Wed Dec 09 2020 - 10:35:19 EST

Hi Qinglang,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on cgroup/for-next]
[also build test WARNING on v5.10-rc7 next-20201209]
[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]

url: https://github.com/0day-ci/linux/commits/Qinglang-Miao/cgroup-Fix-memory-leak-when-parsing-multiple-source-parameters/20201209-201041
base: https://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-next
config: x86_64-randconfig-a004-20201209 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 1968804ac726e7674d5de22bc2204b45857da344)
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 x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# https://github.com/0day-ci/linux/commit/f80ce6cc8c1bde7ecab3fed9f9a514091cec6f56
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Qinglang-Miao/cgroup-Fix-memory-leak-when-parsing-multiple-source-parameters/20201209-201041
git checkout f80ce6cc8c1bde7ecab3fed9f9a514091cec6f56
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

>> kernel/cgroup/cgroup-v1.c:912:23: warning: missing terminating '"' character [-Winvalid-pp-token]
return invalf(fc, "Multiple sources not
^
kernel/cgroup/cgroup-v1.c:913:18: warning: missing terminating '"' character [-Winvalid-pp-token]
supported");
^
kernel/cgroup/cgroup-v1.c:912:12: error: unterminated function-like macro invocation
return invalf(fc, "Multiple sources not
^
include/linux/fs_context.h:241:9: note: macro 'invalf' defined here
#define invalf(fc, fmt, ...) (errorf(fc, fmt, ## __VA_ARGS__), -EINVAL)
^
kernel/cgroup/cgroup-v1.c:1276:40: error: expected expression
__setup("cgroup_no_v1=", cgroup_no_v1);
^
kernel/cgroup/cgroup-v1.c:1276:40: error: expected '}'
kernel/cgroup/cgroup-v1.c:910:42: note: to match this '{'
if (strcmp(param->key, "source") == 0) {
^
kernel/cgroup/cgroup-v1.c:1276:40: error: expected '}'
__setup("cgroup_no_v1=", cgroup_no_v1);
^
kernel/cgroup/cgroup-v1.c:909:24: note: to match this '{'
if (opt == -ENOPARAM) {
^
kernel/cgroup/cgroup-v1.c:1276:40: error: expected '}'
__setup("cgroup_no_v1=", cgroup_no_v1);
^
kernel/cgroup/cgroup-v1.c:902:1: note: to match this '{'
{
^
2 warnings and 5 errors generated.

vim +912 kernel/cgroup/cgroup-v1.c

900
901 int cgroup1_parse_param(struct fs_context *fc, struct fs_parameter *param)
902 {
903 struct cgroup_fs_context *ctx = cgroup_fc2context(fc);
904 struct cgroup_subsys *ss;
905 struct fs_parse_result result;
906 int opt, i;
907
908 opt = fs_parse(fc, cgroup1_fs_parameters, param, &result);
909 if (opt == -ENOPARAM) {
910 if (strcmp(param->key, "source") == 0) {
911 if (fc->source)
> 912 return invalf(fc, "Multiple sources not
913 supported");
914 fc->source = param->string;
915 param->string = NULL;
916 return 0;
917 }
918 for_each_subsys(ss, i) {
919 if (strcmp(param->key, ss->legacy_name))
920 continue;
921 ctx->subsys_mask |= (1 << i);
922 return 0;
923 }
924 return invalfc(fc, "Unknown subsys name '%s'", param->key);
925 }
926 if (opt < 0)
927 return opt;
928
929 switch (opt) {
930 case Opt_none:
931 /* Explicitly have no subsystems */
932 ctx->none = true;
933 break;
934 case Opt_all:
935 ctx->all_ss = true;
936 break;
937 case Opt_noprefix:
938 ctx->flags |= CGRP_ROOT_NOPREFIX;
939 break;
940 case Opt_clone_children:
941 ctx->cpuset_clone_children = true;
942 break;
943 case Opt_cpuset_v2_mode:
944 ctx->flags |= CGRP_ROOT_CPUSET_V2_MODE;
945 break;
946 case Opt_xattr:
947 ctx->flags |= CGRP_ROOT_XATTR;
948 break;
949 case Opt_release_agent:
950 /* Specifying two release agents is forbidden */
951 if (ctx->release_agent)
952 return invalfc(fc, "release_agent respecified");
953 ctx->release_agent = param->string;
954 param->string = NULL;
955 break;
956 case Opt_name:
957 /* blocked by boot param? */
958 if (cgroup_no_v1_named)
959 return -ENOENT;
960 /* Can't specify an empty name */
961 if (!param->size)
962 return invalfc(fc, "Empty name");
963 if (param->size > MAX_CGROUP_ROOT_NAMELEN - 1)
964 return invalfc(fc, "Name too long");
965 /* Must match [\w.-]+ */
966 for (i = 0; i < param->size; i++) {
967 char c = param->string[i];
968 if (isalnum(c))
969 continue;
970 if ((c == '.') || (c == '-') || (c == '_'))
971 continue;
972 return invalfc(fc, "Invalid name");
973 }
974 /* Specifying two names is forbidden */
975 if (ctx->name)
976 return invalfc(fc, "name respecified");
977 ctx->name = param->string;
978 param->string = NULL;
979 break;
980 }
981 return 0;
982 }
983

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

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