On Thu, Apr 8, 2021 at 3:06 PM Gioh Kim <gi-oh....@ionos.com> wrote: > > As the name shows, it checks if strings are equal in case insensitive > manner. > > For example, drivers/infiniband/ulp/rtrs/rtrs-clt-sysfs.c uses > strncasecmp to check that the input via sysfs is "mi". But it would > work even-if the input is "min-wrongcommand". > > I found some more cases using strncasecmp to check the entire string > such as rtrs-clt-sysfs.c does. drivers/pnp/interface.c checks > "disable" command with strncasecmp but it would also work if the > command is "disable-wrong". > > Signed-off-by: Gioh Kim <gi-oh....@ionos.com> you should add the Reported-by: kernel test robot <l...@intel.com> > --- you can add the changelog here after the --- v4->v3: removed #ifdef CONFIG_SYSFS ~ #endif.
The string comparison doesn't depends on CONFIG_SYSFS at all. It looks good to me. Reviewed-by: Jack Wang <jinpu.w...@ionos.com> > include/linux/string.h | 1 + > lib/string.c | 36 ++++++++++++++++++++++++++++-------- > 2 files changed, 29 insertions(+), 8 deletions(-) > > diff --git a/include/linux/string.h b/include/linux/string.h > index 4fcfb56abcf5..36d00ff8013e 100644 > --- a/include/linux/string.h > +++ b/include/linux/string.h > @@ -184,6 +184,7 @@ extern char **argv_split(gfp_t gfp, const char *str, int > *argcp); > extern void argv_free(char **argv); > > extern bool sysfs_streq(const char *s1, const char *s2); > +extern bool sysfs_streqcase(const char *s1, const char *s2); > extern int kstrtobool(const char *s, bool *res); > static inline int strtobool(const char *s, bool *res) > { > diff --git a/lib/string.c b/lib/string.c > index 7548eb715ddb..d0fb02efd5da 100644 > --- a/lib/string.c > +++ b/lib/string.c > @@ -687,6 +687,17 @@ char *strsep(char **s, const char *ct) > EXPORT_SYMBOL(strsep); > #endif > > +static inline bool __streq_terminal(const char *s1, const char *s2) > +{ > + if (*s1 == *s2) > + return true; > + if (!*s1 && *s2 == '\n' && !s2[1]) > + return true; > + if (*s1 == '\n' && !s1[1] && !*s2) > + return true; > + return false; > +} > + > /** > * sysfs_streq - return true if strings are equal, modulo trailing newline > * @s1: one string > @@ -703,17 +714,26 @@ bool sysfs_streq(const char *s1, const char *s2) > s1++; > s2++; > } > - > - if (*s1 == *s2) > - return true; > - if (!*s1 && *s2 == '\n' && !s2[1]) > - return true; > - if (*s1 == '\n' && !s1[1] && !*s2) > - return true; > - return false; > + return __streq_terminal(s1, s2); > } > EXPORT_SYMBOL(sysfs_streq); > > +/** > + * sysfs_streqcase - same to sysfs_streq and case insensitive > + * @s1: one string > + * @s2: another string > + * > + */ > +bool sysfs_streqcase(const char *s1, const char *s2) > +{ > + while (*s1 && tolower(*s1) == tolower(*s2)) { > + s1++; > + s2++; > + } > + return __streq_terminal(s1, s2); > +} > +EXPORT_SYMBOL(sysfs_streqcase); > + > /** > * match_string - matches given string in an array > * @array: array of strings > -- > 2.25.1 >