From: Takashi Iwai <tiwai@xxxxxxx> Subject: ocfs2: use scnprintf() for avoiding potential buffer overflow Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf(). Link: http://lkml.kernel.org/r/20200311093516.25300-1-tiwai@xxxxxxx Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Acked-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx> Cc: Mark Fasheh <mark@xxxxxxxxxx> Cc: Joel Becker <jlbec@xxxxxxxxxxxx> Cc: Joseph Qi <jiangqi903@xxxxxxxxx> Cc: Changwei Ge <gechangwei@xxxxxxx> Cc: Gang He <ghe@xxxxxxxx> Cc: Jun Piao <piaojun@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/ocfs2/cluster/heartbeat.c | 10 +-- fs/ocfs2/cluster/netdebug.c | 4 - fs/ocfs2/dlm/dlmdebug.c | 100 ++++++++++++++++----------------- fs/ocfs2/super.c | 46 +++++++-------- 4 files changed, 80 insertions(+), 80 deletions(-) --- a/fs/ocfs2/cluster/heartbeat.c~ocfs2-use-scnprintf-for-avoiding-potential-buffer-overflow +++ a/fs/ocfs2/cluster/heartbeat.c @@ -1307,7 +1307,7 @@ static int o2hb_debug_open(struct inode case O2HB_DB_TYPE_REGION_NUMBER: reg = (struct o2hb_region *)db->db_data; - out += snprintf(buf + out, PAGE_SIZE - out, "%d\n", + out += scnprintf(buf + out, PAGE_SIZE - out, "%d\n", reg->hr_region_num); goto done; @@ -1317,12 +1317,12 @@ static int o2hb_debug_open(struct inode /* If 0, it has never been set before */ if (lts) lts = jiffies_to_msecs(jiffies - lts); - out += snprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts); + out += scnprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts); goto done; case O2HB_DB_TYPE_REGION_PINNED: reg = (struct o2hb_region *)db->db_data; - out += snprintf(buf + out, PAGE_SIZE - out, "%u\n", + out += scnprintf(buf + out, PAGE_SIZE - out, "%u\n", !!reg->hr_item_pinned); goto done; @@ -1331,8 +1331,8 @@ static int o2hb_debug_open(struct inode } while ((i = find_next_bit(map, db->db_len, i + 1)) < db->db_len) - out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i); - out += snprintf(buf + out, PAGE_SIZE - out, "\n"); + out += scnprintf(buf + out, PAGE_SIZE - out, "%d ", i); + out += scnprintf(buf + out, PAGE_SIZE - out, "\n"); done: i_size_write(inode, out); --- a/fs/ocfs2/cluster/netdebug.c~ocfs2-use-scnprintf-for-avoiding-potential-buffer-overflow +++ a/fs/ocfs2/cluster/netdebug.c @@ -443,8 +443,8 @@ static int o2net_fill_bitmap(char *buf, o2net_fill_node_map(map, sizeof(map)); while ((i = find_next_bit(map, O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) - out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i); - out += snprintf(buf + out, PAGE_SIZE - out, "\n"); + out += scnprintf(buf + out, PAGE_SIZE - out, "%d ", i); + out += scnprintf(buf + out, PAGE_SIZE - out, "\n"); return out; } --- a/fs/ocfs2/dlm/dlmdebug.c~ocfs2-use-scnprintf-for-avoiding-potential-buffer-overflow +++ a/fs/ocfs2/dlm/dlmdebug.c @@ -244,11 +244,11 @@ static int stringify_lockname(const char memcpy((__be64 *)&inode_blkno_be, (char *)&lockname[OCFS2_DENTRY_LOCK_INO_START], sizeof(__be64)); - out += snprintf(buf + out, len - out, "%.*s%08x", + out += scnprintf(buf + out, len - out, "%.*s%08x", OCFS2_DENTRY_LOCK_INO_START - 1, lockname, (unsigned int)be64_to_cpu(inode_blkno_be)); } else - out += snprintf(buf + out, len - out, "%.*s", + out += scnprintf(buf + out, len - out, "%.*s", locklen, lockname); return out; } @@ -260,7 +260,7 @@ static int stringify_nodemap(unsigned lo int i = -1; while ((i = find_next_bit(nodemap, maxnodes, i + 1)) < maxnodes) - out += snprintf(buf + out, len - out, "%d ", i); + out += scnprintf(buf + out, len - out, "%d ", i); return out; } @@ -278,34 +278,34 @@ static int dump_mle(struct dlm_master_li mle_type = "MIG"; out += stringify_lockname(mle->mname, mle->mnamelen, buf + out, len - out); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "\t%3s\tmas=%3u\tnew=%3u\tevt=%1d\tuse=%1d\tref=%3d\n", mle_type, mle->master, mle->new_master, !list_empty(&mle->hb_events), !!mle->inuse, kref_read(&mle->mle_refs)); - out += snprintf(buf + out, len - out, "Maybe="); + out += scnprintf(buf + out, len - out, "Maybe="); out += stringify_nodemap(mle->maybe_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); - out += snprintf(buf + out, len - out, "Vote="); + out += scnprintf(buf + out, len - out, "Vote="); out += stringify_nodemap(mle->vote_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); - out += snprintf(buf + out, len - out, "Response="); + out += scnprintf(buf + out, len - out, "Response="); out += stringify_nodemap(mle->response_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); - out += snprintf(buf + out, len - out, "Node="); + out += scnprintf(buf + out, len - out, "Node="); out += stringify_nodemap(mle->node_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); return out; } @@ -353,7 +353,7 @@ static int debug_purgelist_print(struct int out = 0; unsigned long total = 0; - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Dumping Purgelist for Domain: %s\n", dlm->name); spin_lock(&dlm->spinlock); @@ -365,13 +365,13 @@ static int debug_purgelist_print(struct out += stringify_lockname(res->lockname.name, res->lockname.len, buf + out, len - out); - out += snprintf(buf + out, len - out, "\t%ld\n", + out += scnprintf(buf + out, len - out, "\t%ld\n", (jiffies - res->last_used)/HZ); spin_unlock(&res->spinlock); } spin_unlock(&dlm->spinlock); - out += snprintf(buf + out, len - out, "Total on list: %lu\n", total); + out += scnprintf(buf + out, len - out, "Total on list: %lu\n", total); return out; } @@ -410,7 +410,7 @@ static int debug_mle_print(struct dlm_ct int i, out = 0; unsigned long total = 0, longest = 0, bucket_count = 0; - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Dumping MLEs for Domain: %s\n", dlm->name); spin_lock(&dlm->master_lock); @@ -428,7 +428,7 @@ static int debug_mle_print(struct dlm_ct } spin_unlock(&dlm->master_lock); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Total: %lu, Longest: %lu\n", total, longest); return out; } @@ -467,7 +467,7 @@ static int dump_lock(struct dlm_lock *lo #define DEBUG_LOCK_VERSION 1 spin_lock(&lock->spinlock); - out = snprintf(buf, len, "LOCK:%d,%d,%d,%d,%d,%d:%lld,%d,%d,%d,%d,%d," + out = scnprintf(buf, len, "LOCK:%d,%d,%d,%d,%d,%d:%lld,%d,%d,%d,%d,%d," "%d,%d,%d,%d\n", DEBUG_LOCK_VERSION, list_type, lock->ml.type, lock->ml.convert_type, @@ -491,13 +491,13 @@ static int dump_lockres(struct dlm_lock_ int i; int out = 0; - out += snprintf(buf + out, len - out, "NAME:"); + out += scnprintf(buf + out, len - out, "NAME:"); out += stringify_lockname(res->lockname.name, res->lockname.len, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); #define DEBUG_LRES_VERSION 1 - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "LRES:%d,%d,%d,%ld,%d,%d,%d,%d,%d,%d,%d\n", DEBUG_LRES_VERSION, res->owner, res->state, res->last_used, @@ -509,17 +509,17 @@ static int dump_lockres(struct dlm_lock_ kref_read(&res->refs)); /* refmap */ - out += snprintf(buf + out, len - out, "RMAP:"); + out += scnprintf(buf + out, len - out, "RMAP:"); out += stringify_nodemap(res->refmap, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); /* lvb */ - out += snprintf(buf + out, len - out, "LVBX:"); + out += scnprintf(buf + out, len - out, "LVBX:"); for (i = 0; i < DLM_LVB_LEN; i++) - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%02x", (unsigned char)res->lvb[i]); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); /* granted */ list_for_each_entry(lock, &res->granted, list) @@ -533,7 +533,7 @@ static int dump_lockres(struct dlm_lock_ list_for_each_entry(lock, &res->blocked, list) out += dump_lock(lock, 2, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); return out; } @@ -683,41 +683,41 @@ static int debug_state_print(struct dlm_ } /* Domain: xxxxxxxxxx Key: 0xdfbac769 */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Domain: %s Key: 0x%08x Protocol: %d.%d\n", dlm->name, dlm->key, dlm->dlm_locking_proto.pv_major, dlm->dlm_locking_proto.pv_minor); /* Thread Pid: xxx Node: xxx State: xxxxx */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Thread Pid: %d Node: %d State: %s\n", task_pid_nr(dlm->dlm_thread_task), dlm->node_num, state); /* Number of Joins: xxx Joining Node: xxx */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Number of Joins: %d Joining Node: %d\n", dlm->num_joins, dlm->joining_node); /* Domain Map: xx xx xx */ - out += snprintf(buf + out, len - out, "Domain Map: "); + out += scnprintf(buf + out, len - out, "Domain Map: "); out += stringify_nodemap(dlm->domain_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); /* Exit Domain Map: xx xx xx */ - out += snprintf(buf + out, len - out, "Exit Domain Map: "); + out += scnprintf(buf + out, len - out, "Exit Domain Map: "); out += stringify_nodemap(dlm->exit_domain_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); /* Live Map: xx xx xx */ - out += snprintf(buf + out, len - out, "Live Map: "); + out += scnprintf(buf + out, len - out, "Live Map: "); out += stringify_nodemap(dlm->live_nodes_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); /* Lock Resources: xxx (xxx) */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Lock Resources: %d (%d)\n", atomic_read(&dlm->res_cur_count), atomic_read(&dlm->res_tot_count)); @@ -729,29 +729,29 @@ static int debug_state_print(struct dlm_ cur_mles += atomic_read(&dlm->mle_cur_count[i]); /* MLEs: xxx (xxx) */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "MLEs: %d (%d)\n", cur_mles, tot_mles); /* Blocking: xxx (xxx) */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, " Blocking: %d (%d)\n", atomic_read(&dlm->mle_cur_count[DLM_MLE_BLOCK]), atomic_read(&dlm->mle_tot_count[DLM_MLE_BLOCK])); /* Mastery: xxx (xxx) */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, " Mastery: %d (%d)\n", atomic_read(&dlm->mle_cur_count[DLM_MLE_MASTER]), atomic_read(&dlm->mle_tot_count[DLM_MLE_MASTER])); /* Migration: xxx (xxx) */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, " Migration: %d (%d)\n", atomic_read(&dlm->mle_cur_count[DLM_MLE_MIGRATION]), atomic_read(&dlm->mle_tot_count[DLM_MLE_MIGRATION])); /* Lists: Dirty=Empty Purge=InUse PendingASTs=Empty ... */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Lists: Dirty=%s Purge=%s PendingASTs=%s " "PendingBASTs=%s\n", (list_empty(&dlm->dirty_list) ? "Empty" : "InUse"), @@ -760,12 +760,12 @@ static int debug_state_print(struct dlm_ (list_empty(&dlm->pending_basts) ? "Empty" : "InUse")); /* Purge Count: xxx Refs: xxx */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Purge Count: %d Refs: %d\n", dlm->purge_count, kref_read(&dlm->dlm_refs)); /* Dead Node: xxx */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Dead Node: %d\n", dlm->reco.dead_node); /* What about DLM_RECO_STATE_FINALIZE? */ @@ -775,19 +775,19 @@ static int debug_state_print(struct dlm_ state = "INACTIVE"; /* Recovery Pid: xxxx Master: xxx State: xxxx */ - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "Recovery Pid: %d Master: %d State: %s\n", task_pid_nr(dlm->dlm_reco_thread_task), dlm->reco.new_master, state); /* Recovery Map: xx xx */ - out += snprintf(buf + out, len - out, "Recovery Map: "); + out += scnprintf(buf + out, len - out, "Recovery Map: "); out += stringify_nodemap(dlm->recovery_map, O2NM_MAX_NODES, buf + out, len - out); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); /* Recovery Node State: */ - out += snprintf(buf + out, len - out, "Recovery Node State:\n"); + out += scnprintf(buf + out, len - out, "Recovery Node State:\n"); list_for_each_entry(node, &dlm->reco.node_data, list) { switch (node->state) { case DLM_RECO_NODE_DATA_INIT: @@ -815,7 +815,7 @@ static int debug_state_print(struct dlm_ state = "BAD"; break; } - out += snprintf(buf + out, len - out, "\t%u - %s\n", + out += scnprintf(buf + out, len - out, "\t%u - %s\n", node->node_num, state); } --- a/fs/ocfs2/super.c~ocfs2-use-scnprintf-for-avoiding-potential-buffer-overflow +++ a/fs/ocfs2/super.c @@ -220,31 +220,31 @@ static int ocfs2_osb_dump(struct ocfs2_s int i, out = 0; unsigned long flags; - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Id: %-s Uuid: %-s Gen: 0x%X Label: %-s\n", "Device", osb->dev_str, osb->uuid_str, osb->fs_generation, osb->vol_label); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => State: %d Flags: 0x%lX\n", "Volume", atomic_read(&osb->vol_state), osb->osb_flags); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Block: %lu Cluster: %d\n", "Sizes", osb->sb->s_blocksize, osb->s_clustersize); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Compat: 0x%X Incompat: 0x%X " "ROcompat: 0x%X\n", "Features", osb->s_feature_compat, osb->s_feature_incompat, osb->s_feature_ro_compat); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Opts: 0x%lX AtimeQuanta: %u\n", "Mount", osb->s_mount_opt, osb->s_atime_quantum); if (cconn) { - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Stack: %s Name: %*s " "Version: %d.%d\n", "Cluster", (*osb->osb_cluster_stack == '\0' ? @@ -255,7 +255,7 @@ static int ocfs2_osb_dump(struct ocfs2_s } spin_lock_irqsave(&osb->dc_task_lock, flags); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Pid: %d Count: %lu WakeSeq: %lu " "WorkSeq: %lu\n", "DownCnvt", (osb->dc_task ? task_pid_nr(osb->dc_task) : -1), @@ -264,32 +264,32 @@ static int ocfs2_osb_dump(struct ocfs2_s spin_unlock_irqrestore(&osb->dc_task_lock, flags); spin_lock(&osb->osb_lock); - out += snprintf(buf + out, len - out, "%10s => Pid: %d Nodes:", + out += scnprintf(buf + out, len - out, "%10s => Pid: %d Nodes:", "Recovery", (osb->recovery_thread_task ? task_pid_nr(osb->recovery_thread_task) : -1)); if (rm->rm_used == 0) - out += snprintf(buf + out, len - out, " None\n"); + out += scnprintf(buf + out, len - out, " None\n"); else { for (i = 0; i < rm->rm_used; i++) - out += snprintf(buf + out, len - out, " %d", + out += scnprintf(buf + out, len - out, " %d", rm->rm_entries[i]); - out += snprintf(buf + out, len - out, "\n"); + out += scnprintf(buf + out, len - out, "\n"); } spin_unlock(&osb->osb_lock); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => Pid: %d Interval: %lu\n", "Commit", (osb->commit_task ? task_pid_nr(osb->commit_task) : -1), osb->osb_commit_interval); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => State: %d TxnId: %lu NumTxns: %d\n", "Journal", osb->journal->j_state, osb->journal->j_trans_id, atomic_read(&osb->journal->j_num_trans)); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => GlobalAllocs: %d LocalAllocs: %d " "SubAllocs: %d LAWinMoves: %d SAExtends: %d\n", "Stats", @@ -299,7 +299,7 @@ static int ocfs2_osb_dump(struct ocfs2_s atomic_read(&osb->alloc_stats.moves), atomic_read(&osb->alloc_stats.bg_extends)); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => State: %u Descriptor: %llu Size: %u bits " "Default: %u bits\n", "LocalAlloc", osb->local_alloc_state, @@ -307,7 +307,7 @@ static int ocfs2_osb_dump(struct ocfs2_s osb->local_alloc_bits, osb->local_alloc_default_bits); spin_lock(&osb->osb_lock); - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s => InodeSlot: %d StolenInodes: %d, " "MetaSlot: %d StolenMeta: %d\n", "Steal", osb->s_inode_steal_slot, @@ -316,20 +316,20 @@ static int ocfs2_osb_dump(struct ocfs2_s atomic_read(&osb->s_num_meta_stolen)); spin_unlock(&osb->osb_lock); - out += snprintf(buf + out, len - out, "OrphanScan => "); - out += snprintf(buf + out, len - out, "Local: %u Global: %u ", + out += scnprintf(buf + out, len - out, "OrphanScan => "); + out += scnprintf(buf + out, len - out, "Local: %u Global: %u ", os->os_count, os->os_seqno); - out += snprintf(buf + out, len - out, " Last Scan: "); + out += scnprintf(buf + out, len - out, " Last Scan: "); if (atomic_read(&os->os_state) == ORPHAN_SCAN_INACTIVE) - out += snprintf(buf + out, len - out, "Disabled\n"); + out += scnprintf(buf + out, len - out, "Disabled\n"); else - out += snprintf(buf + out, len - out, "%lu seconds ago\n", + out += scnprintf(buf + out, len - out, "%lu seconds ago\n", (unsigned long)(ktime_get_seconds() - os->os_scantime)); - out += snprintf(buf + out, len - out, "%10s => %3s %10s\n", + out += scnprintf(buf + out, len - out, "%10s => %3s %10s\n", "Slots", "Num", "RecoGen"); for (i = 0; i < osb->max_slots; ++i) { - out += snprintf(buf + out, len - out, + out += scnprintf(buf + out, len - out, "%10s %c %3d %10d\n", " ", (i == osb->slot_num ? '*' : ' '), _
