Refactor sysfs to improve sanitization

LibOS/shim/include/shim_fs_pseudo.h

@@ -209,4 +209,23 @@ int sys_cache_load(struct shim_dentry* dent, char** out_data, size_t* out_size);
 bool sys_cpu_online_name_exists(struct shim_dentry* parent, const char* name);
 int sys_cpu_online_list_names(struct shim_dentry* parent, readdir_callback_t callback, void* arg);
 
+/* Converts an integer to a string, optionally appending a given single-letter unit suffix
+ * (see enum size_multiplier for possible values).
+ * Note: This function adds a newline at end of the string. */
+int sys_convert_int_to_sizestr(uint64_t val, enum size_multiplier size_mult, char* str,
+                               size_t buf_size);
+
+/* Converts PAL_RES_RANGE_INFO to a string representation.
+ * Example output when sep == ',': "10-63,68,70-127".
+ * Note: This function adds a newline at end of the string. */
+int sys_convert_ranges_to_str(const PAL_RES_RANGE_INFO* resource_range_info, char* str,
+                              size_t buf_size, const char* sep);
+
+/* Converts PAL_RES_RANGE_INFO to a sysfs CPU bitmask representation with bitmask size based on the
+ * possible cores count in the system.
+ * Example output for 64 cores in total and ranges 0-15,48-55: "00ff0000,0000ffff".
+ * Note: This function adds a newline at end of the string. */
+int sys_convert_ranges_to_cpu_bitmap_str(const PAL_RES_RANGE_INFO* resource_range_info, char* str,
+                                         size_t buf_size);
+
 #endif /* SHIM_FS_PSEUDO_H_ */

LibOS/shim/src/fs/proc/info.c

@@ -113,7 +113,8 @@ int proc_cpuinfo_load(struct shim_dentry* dent, char** out_data, size_t* out_siz
         size += ret;                                                  \
     } while (0)
 
-    for (size_t n = 0; n < g_pal_control->cpu_info.online_logical_cores; n++) {
+    uint64_t online_logical_cores = g_pal_control->topo_info.online_logical_cores.resource_count;
+    for (uint64_t n = 0; n < online_logical_cores; n++) {
         /* Below strings must match exactly the strings retrieved from /proc/cpuinfo
          * (see Linux's arch/x86/kernel/cpu/proc.c) */
         ADD_INFO("processor\t: %lu\n", n);
@@ -122,9 +123,9 @@ int proc_cpuinfo_load(struct shim_dentry* dent, char** out_data, size_t* out_siz
         ADD_INFO("model\t\t: %lu\n", g_pal_control->cpu_info.cpu_model);
         ADD_INFO("model name\t: %s\n", g_pal_control->cpu_info.cpu_brand);
         ADD_INFO("stepping\t: %lu\n", g_pal_control->cpu_info.cpu_stepping);
-        ADD_INFO("physical id\t: %d\n", g_pal_control->cpu_info.cpu_socket[n]);
+        ADD_INFO("physical id\t: %d\n", g_pal_control->topo_info.core_topology[n].cpu_socket);
         ADD_INFO("core id\t\t: %lu\n", n);
-        ADD_INFO("cpu cores\t: %lu\n", g_pal_control->cpu_info.physical_cores_per_socket);
+        ADD_INFO("cpu cores\t: %lu\n", g_pal_control->topo_info.physical_cores_per_socket);
         double bogomips = g_pal_control->cpu_info.cpu_bogomips;
         // Apparently Gramine snprintf cannot into floats.
         ADD_INFO("bogomips\t: %lu.%02lu\n", (unsigned long)bogomips,

LibOS/shim/src/fs/sys/cache_info.c

@@ -27,25 +27,40 @@ int sys_cache_load(struct shim_dentry* dent, char** out_data, size_t* out_size)
 
     const char* name = dent->name;
     PAL_CORE_CACHE_INFO* cache = &g_pal_control->topo_info.core_topology[cpu_num].cache[cache_num];
-    const char* str;
+    char str[PAL_SYSFS_MAP_FILESZ] = {'\0'};
     if (strcmp(name, "shared_cpu_map") == 0) {
-        str = cache->shared_cpu_map;
+        ret = sys_convert_ranges_to_cpu_bitmap_str(&cache->shared_cpu_map, str, sizeof(str));
     } else if (strcmp(name, "level") == 0) {
-        str = cache->level;
+        ret = sys_convert_int_to_sizestr(cache->level, MULTIPLIER_NONE, str, sizeof(str));
     } else if (strcmp(name, "type") == 0) {
-        str = cache->type;
+        switch (cache->type) {
+            case CACHE_TYPE_DATA:
+                ret = snprintf(str, sizeof(str), "%s", "Data\n");
+                break;
+            case CACHE_TYPE_INSTRUCTION:
+                ret = snprintf(str, sizeof(str), "%s", "Instruction\n");
+                break;
+            case CACHE_TYPE_UNIFIED:
+                ret = snprintf(str, sizeof(str), "%s", "Unified\n");
+                break;
+            default:
+                ret = -ENOENT;
+        }
     } else if (strcmp(name, "size") == 0) {
-        str = cache->size;
+        ret = sys_convert_int_to_sizestr(cache->size, cache->size_multiplier, str, sizeof(str));
     } else if (strcmp(name, "coherency_line_size") == 0) {
-        str = cache->coherency_line_size;
+        ret = sys_convert_int_to_sizestr(cache->coherency_line_size, MULTIPLIER_NONE, str, sizeof(str));
     } else if (strcmp(name, "number_of_sets") == 0) {
-        str = cache->number_of_sets;
+        ret = sys_convert_int_to_sizestr(cache->number_of_sets, MULTIPLIER_NONE, str, sizeof(str));
     } else if (strcmp(name, "physical_line_partition") == 0) {
-        str = cache->physical_line_partition;
+        ret = sys_convert_int_to_sizestr(cache->physical_line_partition, MULTIPLIER_NONE, str,
+                                         sizeof(str));
     } else {
         log_debug("unrecognized file: %s", name);
-        return -ENOENT;
+        ret = -ENOENT;
     }
 
+    if (ret < 0)
+        return ret;
     return sys_load(str, out_data, out_size);
 }

LibOS/shim/src/fs/sys/cpu_info.c

@@ -13,18 +13,23 @@
 #include "shim_fs_pseudo.h"
 
 int sys_cpu_general_load(struct shim_dentry* dent, char** out_data, size_t* out_size) {
+    int ret;
     const char* name = dent->name;
-    const char* str;
+    char str[PAL_SYSFS_BUF_FILESZ] = {'\0'};
 
     if (strcmp(name, "online") == 0) {
-        str = g_pal_control->topo_info.online_logical_cores;
+        ret = sys_convert_ranges_to_str(&g_pal_control->topo_info.online_logical_cores, str,
+                                        sizeof(str), ",");
     } else if (strcmp(name, "possible") == 0) {
-        str = g_pal_control->topo_info.possible_logical_cores;
+        ret = sys_convert_ranges_to_str(&g_pal_control->topo_info.possible_logical_cores, str,
+                                        sizeof(str), ",");
     } else {
         log_debug("unrecognized file: %s", name);
-        return -ENOENT;
+        ret = -ENOENT;
     }
 
+    if (ret < 0)
+        return ret;
     return sys_load(str, out_data, out_size);
 }
 
@@ -37,27 +42,30 @@ int sys_cpu_load(struct shim_dentry* dent, char** out_data, size_t* out_size) {
 
     const char* name = dent->name;
     PAL_CORE_TOPO_INFO* core_topology = &g_pal_control->topo_info.core_topology[cpu_num];
-    const char* str;
-    char buf[12];
+    char str[PAL_SYSFS_MAP_FILESZ] = {'\0'};
     if (strcmp(name, "online") == 0) {
         /* `cpu/cpuX/online` is not present for cpu0 */
         if (cpu_num == 0)
             return -ENOENT;
-        str = core_topology->is_logical_core_online;
+        ret = sys_convert_int_to_sizestr(core_topology->is_logical_core_online, MULTIPLIER_NONE,
+                                         str, sizeof(str));
     } else if (strcmp(name, "core_id") == 0) {
-        str = core_topology->core_id;
+        ret = sys_convert_int_to_sizestr(core_topology->core_id, MULTIPLIER_NONE, str, sizeof(str));
     } else if (strcmp(name, "physical_package_id") == 0) {
-        snprintf(buf, sizeof(buf), "%d\n", g_pal_control->cpu_info.cpu_socket[cpu_num]);
-        str = buf;
+        ret = sys_convert_int_to_sizestr(core_topology->cpu_socket, MULTIPLIER_NONE, str,
+                                         sizeof(str));
     } else if (strcmp(name, "core_siblings") == 0) {
-        str = core_topology->core_siblings;
+        ret = sys_convert_ranges_to_cpu_bitmap_str(&core_topology->core_siblings, str, sizeof(str));
     } else if (strcmp(name, "thread_siblings") == 0) {
-        str = core_topology->thread_siblings;
+        ret = sys_convert_ranges_to_cpu_bitmap_str(&core_topology->thread_siblings, str,
+                                                   sizeof(str));
     } else {
         log_debug("unrecognized file: %s", name);
-        return -ENOENT;
+        ret = -ENOENT;
     }
 
+    if (ret < 0)
+        return ret;
     return sys_load(str, out_data, out_size);
 }
 

LibOS/shim/src/fs/sys/fs.c

@@ -14,6 +14,119 @@
 #include "shim_fs_pseudo.h"
 #include "stat.h"
 
+int sys_convert_int_to_sizestr(uint64_t val, enum size_multiplier size_mult, char* str,
+                               size_t buf_size) {
+    int ret = 0;
+
+    switch (size_mult) {
+        case MULTIPLIER_KB:
+            ret = snprintf(str, buf_size, "%luK\n", val);
+            break;
+        case MULTIPLIER_MB:
+            ret = snprintf(str, buf_size, "%luM\n", val);
+            break;
+        case MULTIPLIER_GB:
+            ret = snprintf(str, buf_size, "%luG\n", val);
+            break;
+        default:
+            ret = snprintf(str, buf_size, "%lu\n", val);
+            break;
+    }
+
+    if (ret >= (int)buf_size)
+        ret = -EOVERFLOW;
+    return ret;
+}
+
+int sys_convert_ranges_to_str(const PAL_RES_RANGE_INFO* resource_range_info, char* str,
+                              size_t buf_size, const char* sep) {
+    uint64_t range_cnt = resource_range_info->range_count;
+    size_t offset = 0;
+    for (uint64_t i = 0; i < range_cnt; i++) {
+        if (offset > buf_size)
+            return -ENOMEM;
+
+        int ret;
+        if (resource_range_info->ranges[i].end == resource_range_info->ranges[i].start) {
+            ret = snprintf(str + offset, buf_size - offset, "%lu%s",
+                           resource_range_info->ranges[i].start, (i + 1 == range_cnt) ? "\n" : sep);
+        } else {
+            ret = snprintf(str + offset, buf_size - offset, "%lu-%lu%s",
+                           resource_range_info->ranges[i].start, resource_range_info->ranges[i].end,
+                           (i + 1 == range_cnt) ? "\n" : sep);
+        }
+
+        if (ret < 0)
+            return ret;
+
+        /* Truncation has occurred */
+        if ((size_t)ret >= buf_size)
+            return -EOVERFLOW;
+
+        offset += ret;
+    }
+    return 0;
+}
+
+int sys_convert_ranges_to_cpu_bitmap_str(const PAL_RES_RANGE_INFO* resource_range_info, char* str,
+                                         size_t buf_size) {
+    int ret;
+
+    /* Extract cpumask from the ranges */
+    uint64_t possible_cores =  g_pal_control->topo_info.possible_logical_cores.resource_count;
+    uint64_t num_cpumask = BITS_TO_INTS(possible_cores);
+    uint32_t* bitmap = (uint32_t*)calloc(num_cpumask, sizeof(uint32_t));
+    if (!bitmap)
+        return -ENOMEM;
+
+    for (uint64_t i = 0; i < resource_range_info->range_count; i++) {
+        uint64_t start = resource_range_info->ranges[i].start;
+        uint64_t end = resource_range_info->ranges[i].end;
+
+        for (uint64_t j = start; j <= end; j++) {
+            uint64_t index = j / BITS_IN_TYPE(int);
+            assert(index < num_cpumask);
+
+            bitmap[index] |= 1U << (j % BITS_IN_TYPE(int));
+        }
+    }
+
+    /* Convert cpumask to strings */
+    size_t offset = 0;
+    for (uint64_t j = num_cpumask; j > 0; j--) {
+        if (offset > buf_size) {
+            ret = -ENOMEM;
+            goto out;
+        }
+
+        /* Linux doesn't print leading zeroes for systems with less than 32 cores, e.g. "fff" for
+         * 12 cores; we mimic this behavior. */
+        if (possible_cores >= 32) {
+            ret = snprintf(str + offset, buf_size - offset, "%08x%s", bitmap[j-1],
+                           (j-1 == 0) ? "\n" : ",");
+        } else {
+            ret = snprintf(str + offset, buf_size - offset, "%x%s", bitmap[j-1],
+                           (j-1 == 0) ? "\n" : ",");
+        }
+
+        if (ret < 0)
+            goto out;
+
+        /* Truncation has occurred */
+        if ((size_t)ret >= buf_size) {
+            ret = -EOVERFLOW;
+            goto out;
+        }
+
+        offset += ret;
+    }
+    ret = 0;
+
+out:
+    free(bitmap);
+    return ret;
+}
+
 static int sys_resource(struct shim_dentry* parent, const char* name, unsigned int* out_num,
                         readdir_callback_t callback, void* arg) {
     const char* parent_name = parent->name;
@@ -22,10 +135,10 @@ static int sys_resource(struct shim_dentry* parent, const char* name, unsigned i
     const char* prefix;
 
     if (strcmp(parent_name, "node") == 0) {
-        pal_total = g_pal_control->topo_info.num_online_nodes;
+        pal_total = g_pal_control->topo_info.nodes.resource_count;
         prefix = "node";
     } else if (strcmp(parent_name, "cpu") == 0) {
-        pal_total = g_pal_control->cpu_info.online_logical_cores;
+        pal_total = g_pal_control->topo_info.online_logical_cores.resource_count;
         prefix = "cpu";
     } else if (strcmp(parent_name, "cache") == 0) {
         pal_total = g_pal_control->topo_info.num_cache_index;
@@ -130,6 +243,7 @@ static void init_cpu_dir(struct pseudo_node* cpu) {
     pseudo_add_str(indexX, "type", &sys_cache_load);
     pseudo_add_str(indexX, "size", &sys_cache_load);
     pseudo_add_str(indexX, "coherency_line_size", &sys_cache_load);
+    pseudo_add_str(indexX, "number_of_sets", &sys_cache_load);
     pseudo_add_str(indexX, "physical_line_partition", &sys_cache_load);
 }
 

LibOS/shim/src/fs/sys/node_info.c

@@ -12,15 +12,20 @@
 #include "shim_fs_pseudo.h"
 
 int sys_node_general_load(struct shim_dentry* dent, char** out_data, size_t* out_size) {
+    int ret;
+
     const char* name = dent->name;
-    const char* str;
-    if (strcmp(name, "online") == 0) {
-        str = g_pal_control->topo_info.online_nodes;
-    } else {
+    char str[PAL_SYSFS_BUF_FILESZ] = {'\0'};
+
+    if (strcmp(name, "online") != 0) {
         log_debug("unrecognized file: %s", name);
         return -ENOENT;
     }
 
+    ret = sys_convert_ranges_to_str(&g_pal_control->topo_info.nodes, str, sizeof(str), ",");
+    if (ret < 0)
+        return ret;
+
     return sys_load(str, out_data, out_size);
 }
 
@@ -33,23 +38,29 @@ int sys_node_load(struct shim_dentry* dent, char** out_data, size_t* out_size) {
 
     const char* name = dent->name;
     PAL_NUMA_TOPO_INFO* numa_topology = &g_pal_control->topo_info.numa_topology[node_num];
-    const char* str = NULL;
+    char str[PAL_SYSFS_MAP_FILESZ] = {'\0'};
     if (strcmp(name, "cpumap" ) == 0) {
-        str = numa_topology->cpumap;
+        ret = sys_convert_ranges_to_cpu_bitmap_str(&numa_topology->cpumap, str, sizeof(str));
     } else if (strcmp(name, "distance") == 0) {
-        str = numa_topology->distance;
+        ret = sys_convert_ranges_to_str(&numa_topology->distance, str, sizeof(str), " ");
     } else if (strcmp(name, "nr_hugepages") == 0) {
         const char* parent_name = dent->parent->name;
         if (strcmp(parent_name, "hugepages-2048kB") == 0) {
-            str = numa_topology->hugepages[HUGEPAGES_2M].nr_hugepages;
+            ret = sys_convert_int_to_sizestr(numa_topology->nr_hugepages[HUGEPAGES_2M],
+                                             MULTIPLIER_NONE, str, sizeof(str));
         } else if (strcmp(parent_name, "hugepages-1048576kB") == 0) {
-            str = numa_topology->hugepages[HUGEPAGES_1G].nr_hugepages;
+            ret = sys_convert_int_to_sizestr(numa_topology->nr_hugepages[HUGEPAGES_1G],
+                                             MULTIPLIER_NONE, str, sizeof(str));
+        } else {
+            log_debug("unrecognized hugepage file: %s", parent_name);
+            ret = -ENOENT;
         }
-    }
-    if (!str) {
+    } else {
         log_debug("unrecognized file: %s", name);
-        return -ENOENT;
+        ret = -ENOENT;
     }
 
+    if (ret < 0)
+        return ret;
     return sys_load(str, out_data, out_size);
 }

LibOS/shim/src/sys/shim_sched.c

@@ -175,7 +175,7 @@ long shim_do_sched_setaffinity(pid_t pid, unsigned int cpumask_size, unsigned lo
 
 long shim_do_sched_getaffinity(pid_t pid, unsigned int cpumask_size, unsigned long* user_mask_ptr) {
     int ret;
-    size_t cpu_cnt = g_pal_control->cpu_info.online_logical_cores;
+    size_t cpu_cnt = g_pal_control->topo_info.online_logical_cores.resource_count;
 
     /* Check if user_mask_ptr is valid */
     if (!is_user_memory_writable(user_mask_ptr, cpumask_size))

LibOS/shim/test/regression/test_libos.py

@@ -886,6 +886,7 @@ def test_040_sysfs(self):
                 self.assertIn(f'{cache}/type: file', lines)
                 self.assertIn(f'{cache}/size: file', lines)
                 self.assertIn(f'{cache}/coherency_line_size: file', lines)
+                self.assertIn(f'{cache}/number_of_sets: file', lines)
                 self.assertIn(f'{cache}/physical_line_partition: file', lines)
 
         self.assertIn('/sys/devices/system/node: directory', lines)