criu/files: Don't cache fd ids for device files

Restore operation fails when we perform CR operation of multiple independent proceses that have device files because criu caches the ids for the device files with same mnt_ids, inode pair. This change ensures that even in case of a cached id found for a device, a unique subid is generated and returned which is used for dumping. Suggested-by: Andrei Vagin <[email protected]> Signed-off-by: Rajneesh Bhardwaj <[email protected]>
adrianreber · Sep 23, 2021 · 0c38a94 · 0c38a94
1 parent d3b62a0
commit 0c38a94
Showing 1 changed file with 8 additions and 2 deletions.
diff --git a/criu/file-ids.c b/criu/file-ids.c
@@ -77,8 +77,14 @@ int fd_id_generate_special(struct fd_parms *p, u32 *id)
 
 		fi = fd_id_cache_lookup(p);
 		if (fi) {
-			*id = fi->id;
-			return 0;
+			if (p->stat.st_mode & (S_IFCHR | S_IFBLK)) {
+				/* Don't cache the id for mapped devices */
+				*id = fd_tree.subid++;
+				return 1;
+			} else {
+				*id = fi->id;
+				return 0;
+			}
 		}
 	}