diff options
| -rw-r--r-- | fs/smb/server/smbacl.c | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/fs/smb/server/smbacl.c b/fs/smb/server/smbacl.c index bba26a0355bb..a1de89cc09be 100644 --- a/fs/smb/server/smbacl.c +++ b/fs/smb/server/smbacl.c @@ -1106,8 +1106,24 @@ int smb_inherit_dacl(struct ksmbd_conn *conn, goto free_parent_pntsd; } - aces_base = kmalloc(sizeof(struct smb_ace) * num_aces * 2, - KSMBD_DEFAULT_GFP); + aces_size = pdacl_size - sizeof(struct smb_acl); + + /* + * Validate num_aces against the DACL payload before allocating. + * Each ACE must be at least as large as its fixed-size header + * (up to the SID base), so num_aces cannot exceed the payload + * divided by the minimum ACE size. This mirrors the existing + * check in parse_dacl(). + */ + if (num_aces > aces_size / (offsetof(struct smb_ace, sid) + + offsetof(struct smb_sid, sub_auth) + + sizeof(__le16))) { + rc = -EINVAL; + goto free_parent_pntsd; + } + + aces_base = kmalloc_array(num_aces * 2, sizeof(struct smb_ace), + KSMBD_DEFAULT_GFP); if (!aces_base) { rc = -ENOMEM; goto free_parent_pntsd; @@ -1116,7 +1132,6 @@ int smb_inherit_dacl(struct ksmbd_conn *conn, aces = (struct smb_ace *)aces_base; parent_aces = (struct smb_ace *)((char *)parent_pdacl + sizeof(struct smb_acl)); - aces_size = acl_len - sizeof(struct smb_acl); if (pntsd_type & DACL_AUTO_INHERITED) inherited_flags = INHERITED_ACE; @@ -1124,11 +1139,14 @@ int smb_inherit_dacl(struct ksmbd_conn *conn, for (i = 0; i < num_aces; i++) { int pace_size; - if (offsetof(struct smb_ace, access_req) > aces_size) + if (aces_size < offsetof(struct smb_ace, sid) + + CIFS_SID_BASE_SIZE) break; pace_size = le16_to_cpu(parent_aces->size); - if (pace_size > aces_size) + if (pace_size > aces_size || + pace_size < offsetof(struct smb_ace, sid) + + CIFS_SID_BASE_SIZE) break; aces_size -= pace_size; |