remove_feature() didn't correctly handle feature strings that used
whitespace other than spaces, which the kernel allows. It also didn't
check if the feature string to be removed was part of a larger feature
token. Finally, it did a lot of unnecessary work. By failing if the
feature string to be removed contains leading or trailing whitespace,
the function can be significanly simplified.
Signed-off-by: Benjamin Marzinski <bmarz...@redhat.com>
---
libmultipath/structs.c | 82 +++++++++++++++---------------------------
1 file changed, 29 insertions(+), 53 deletions(-)
diff --git a/libmultipath/structs.c b/libmultipath/structs.c
index 49621cb3..1f9945e0 100644
--- a/libmultipath/structs.c
+++ b/libmultipath/structs.c
@@ -6,6 +6,7 @@
#include <unistd.h>
#include <libdevmapper.h>
#include <libudev.h>
+#include <ctype.h>
#include "checkers.h"
#include "vector.h"
@@ -663,7 +664,7 @@ int add_feature(char **f, const char *n)
int remove_feature(char **f, const char *o)
{
- int c = 0, d, l;
+ int c = 0, d;
char *e, *p, *n;
const char *q;
@@ -674,33 +675,35 @@ int remove_feature(char **f, const char *o)
if (!o || *o == '\0')
return 0;
- /* Check if not present */
- if (!strstr(*f, o))
+ d = strlen(o);
+ if (isspace(*o) || isspace(*(o + d - 1))) {
+ condlog(0, "internal error: feature \"%s\" has leading or
trailing spaces", o);
+ return 1;
+ }
+
+ /* Check if present and not part of a larger feature token*/
+ p = *f + 1; /* the size must be at the start of the features string */
+ while ((p = strstr(p, o)) != NULL) {
+ if (isspace(*(p - 1)) &&
+ (isspace(*(p + d)) || *(p + d) == '\0'))
+ break;
+ p += d;
+ }
+ if (!p)
return 0;
/* Get feature count */
c = strtoul(*f, &e, 10);
- if (*f == e)
- /* parse error */
+ if (*f == e || !isspace(*e)) {
+ condlog(0, "parse error in feature string \"%s\"", *f);
return 1;
-
- /* Normalize features */
- while (*o == ' ') {
- o++;
}
- /* Just spaces, return */
- if (*o == '\0')
- return 0;
- q = o + strlen(o);
- while (*q == ' ')
- q--;
- d = (int)(q - o);
/* Update feature count */
c--;
q = o;
- while (q[0] != '\0') {
- if (q[0] == ' ' && q[1] != ' ' && q[1] != '\0')
+ while (*q != '\0') {
+ if (isspace(*q) && !isspace(*(q + 1)) && *(q + 1) != '\0')
c--;
q++;
}
@@ -714,15 +717,8 @@ int remove_feature(char **f, const char *o)
goto out;
}
- /* Search feature to be removed */
- e = strstr(*f, o);
- if (!e)
- /* Not found, return */
- return 0;
-
/* Update feature count space */
- l = strlen(*f) - d;
- n = malloc(l + 1);
+ n = malloc(strlen(*f) - d + 1);
if (!n)
return 1;
@@ -732,36 +728,16 @@ int remove_feature(char **f, const char *o)
* Copy existing features up to the feature
* about to be removed
*/
- p = strchr(*f, ' ');
- if (!p) {
- /* Internal error, feature string inconsistent */
- free(n);
- return 1;
- }
- while (*p == ' ')
- p++;
- p--;
- if (e != p) {
- do {
- e--;
- d++;
- } while (*e == ' ');
- e++; d--;
- strncat(n, p, (size_t)(e - p));
- p += (size_t)(e - p);
- }
+ strncat(n, e, (size_t)(p - e));
/* Skip feature to be removed */
p += d;
-
/* Copy remaining features */
- if (strlen(p)) {
- while (*p == ' ')
- p++;
- if (strlen(p)) {
- p--;
- strcat(n, p);
- }
- }
+ while (isspace(*p))
+ p++;
+ if (*p != '\0')
+ strcat(n, p);
+ else
+ strchop(n);
out:
free(*f);
--
2.17.2
--
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