libmultipath: coalesce_paths: fix size mismatch handling
authorMartin Wilck <mwilck@suse.com>
Mon, 10 Dec 2018 09:49:51 +0000 (10:49 +0100)
committerChristophe Varoqui <christophe.varoqui@opensvc.com>
Mon, 10 Dec 2018 23:40:58 +0000 (00:40 +0100)
When there are paths with the same WWID but different sizes, and
coalesce_paths() walks the pathvec, it checks paths _after_
the current one for size mismatch and sets ACT_REJECT. However,
these paths will be reached in the main loop later, and this time
the already handled paths will not be checked for size mismatch;
thus a map could be created, possibly even with mismatching
devices.

Fix that by tracking which paths were already discarded, and
skipping them in the main loop later.

Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Martin Wilck <mwilck@suse.com>
libmultipath/configure.c
libmultipath/util.h

index 406cd4c..f48664a 100644 (file)
@@ -1009,6 +1009,7 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
        vector pathvec = vecs->pathvec;
        struct config *conf;
        int allow_queueing;
+       uint64_t *size_mismatch_seen;
 
        /* ignore refwwid if it's empty */
        if (refwwid && !strlen(refwwid))
@@ -1019,6 +1020,14 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
                        pp1->mpp = NULL;
                }
        }
+
+       if (VECTOR_SIZE(pathvec) == 0)
+               return 0;
+       size_mismatch_seen = calloc((VECTOR_SIZE(pathvec) - 1) / 64 + 1,
+                                   sizeof(uint64_t));
+       if (size_mismatch_seen == NULL)
+               return 1;
+
        vector_foreach_slot (pathvec, pp1, k) {
                int invalid;
                /* skip this path for some reason */
@@ -1038,8 +1047,8 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
                        continue;
                }
 
-               /* 2. if path already coalesced */
-               if (pp1->mpp)
+               /* 2. if path already coalesced, or seen and discarded */
+               if (pp1->mpp || is_bit_set_in_array(k, size_mismatch_seen))
                        continue;
 
                /* 3. if path has disappeared */
@@ -1088,9 +1097,10 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
                                 * ouch, avoid feeding that to the DM
                                 */
                                condlog(0, "%s: size %llu, expected %llu. "
-                                       "Discard", pp2->dev_t, pp2->size,
+                                       "Discard", pp2->dev, pp2->size,
                                        mpp->size);
                                mpp->action = ACT_REJECT;
+                               set_bit_in_array(i, size_mismatch_seen);
                        }
                }
                verify_paths(mpp, vecs);
@@ -1119,8 +1129,9 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
                                        "ignoring" : "removing");
                                remove_map(mpp, vecs, 0);
                                continue;
-                       } else /* if (r == DOMAP_RETRY) */
-                               return r;
+                       } else /* if (r == DOMAP_RETRY && !is_daemon) */ {
+                               goto out;
+                       }
                }
                if (r == DOMAP_DRY)
                        continue;
@@ -1161,8 +1172,10 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
 
                if (newmp) {
                        if (mpp->action != ACT_REJECT) {
-                               if (!vector_alloc_slot(newmp))
-                                       return 1;
+                               if (!vector_alloc_slot(newmp)) {
+                                       r = 1;
+                                       goto out;
+                               }
                                vector_set_slot(newmp, mpp);
                        }
                        else
@@ -1193,7 +1206,10 @@ int coalesce_paths (struct vectors * vecs, vector newmp, char * refwwid,
                                condlog(2, "%s: remove (dead)", alias);
                }
        }
-       return 0;
+       r = 0;
+out:
+       free(size_mismatch_seen);
+       return r;
 }
 
 struct udev_device *get_udev_device(const char *dev, enum devtypes dev_type)
index a818e29..1f13c91 100644 (file)
@@ -3,6 +3,7 @@
 
 #include <sys/types.h>
 #include <inttypes.h>
+#include <stdbool.h>
 
 size_t strchop(char *);
 int basenamecpy (const char *src, char *dst, size_t size);
@@ -39,4 +40,19 @@ struct scandir_result {
 };
 void free_scandir_result(struct scandir_result *);
 
+static inline bool is_bit_set_in_array(unsigned int bit, const uint64_t *arr)
+{
+       return arr[bit / 64] & (1ULL << (bit % 64)) ? 1 : 0;
+}
+
+static inline void set_bit_in_array(unsigned int bit, uint64_t *arr)
+{
+       arr[bit / 64] |= (1ULL << (bit % 64));
+}
+
+static inline void clear_bit_in_array(unsigned int bit, uint64_t *arr)
+{
+       arr[bit / 64] &= ~(1ULL << (bit % 64));
+}
+
 #endif /* _UTIL_H */