[apparmor] [patch 1/5] parser - use DUP_STRING more widely and detect strdup errors

[Tyler Hicks]

On 2013-09-05 01:18:54, Steve Beattie wrote:
> This patch moves the DUP_STRING macro to parser.h and modifies
> it to accept a goto error target, that will be jumped to if the
> call to strdup(3) fails. It also uses it in additional locations
> where copying structures occurs, as well as detecting additional
> cases where a structure duplication might have failed but not been
> propagated outward.
> 
> Signed-off-by: Steve Beattie <steve at nxnw.org>

Acked-by: Tyler Hicks <tyhicks at canonical.com>

> 
> ---
>  parser/dbus.c        |   19 ++++++++++---------
>  parser/mount.c       |   16 ++++++++++++----
>  parser/parser.h      |    7 +++++++
>  parser/parser_misc.c |   10 +++++++---
>  4 files changed, 36 insertions(+), 16 deletions(-)
> 
> Index: b/parser/dbus.c
> ===================================================================
> --- a/parser/dbus.c
> +++ b/parser/dbus.c
> @@ -141,9 +141,6 @@ out:
>  	return ent;
>  }
>  
> -#define DUP_STRING(orig, new, field) \
> -	(new)->field = (orig)->field ? strdup((orig)->field) : NULL
> -
>  struct dbus_entry *dup_dbus_entry(struct dbus_entry *orig)
>  {
>  	struct dbus_entry *ent = NULL;
> @@ -151,12 +148,12 @@ struct dbus_entry *dup_dbus_entry(struct
>  	if (!ent)
>  		return NULL;
>  
> -	DUP_STRING(orig, ent, bus);
> -	DUP_STRING(orig, ent, name);
> -	DUP_STRING(orig, ent, peer_label);
> -	DUP_STRING(orig, ent, path);
> -	DUP_STRING(orig, ent, interface);
> -	DUP_STRING(orig, ent, member);
> +	DUP_STRING(orig, ent, bus, err);
> +	DUP_STRING(orig, ent, name, err);
> +	DUP_STRING(orig, ent, peer_label, err);
> +	DUP_STRING(orig, ent, path, err);
> +	DUP_STRING(orig, ent, interface, err);
> +	DUP_STRING(orig, ent, member, err);
>  	ent->mode = orig->mode;
>  	ent->audit = orig->audit;
>  	ent->deny = orig->deny;
> @@ -164,6 +161,10 @@ struct dbus_entry *dup_dbus_entry(struct
>  	ent->next = orig->next;
>  
>  	return ent;
> +
> +err:
> +	free_dbus_entry(ent);
> +	return NULL;
>  }
>  
>  void print_dbus_entry(struct dbus_entry *ent)
> Index: b/parser/mount.c
> ===================================================================
> --- a/parser/mount.c
> +++ b/parser/mount.c
> @@ -466,7 +466,6 @@ void free_mnt_entry(struct mnt_entry *en
>  	free(ent);
>  }
>  
> -
>  struct mnt_entry *dup_mnt_entry(struct mnt_entry *orig)
>  {
>  	struct mnt_entry *entry = NULL;
> @@ -475,12 +474,17 @@ struct mnt_entry *dup_mnt_entry(struct m
>  	if (!entry)
>  		return NULL;
>  
> -	entry->mnt_point = orig->mnt_point ? strdup(orig->mnt_point) : NULL;
> -	entry->device = orig->device ? strdup(orig->device) : NULL;
> -	entry->trans = orig->trans ? strdup(orig->trans) : NULL;
> +	DUP_STRING(orig, entry, mnt_point, err);
> +	DUP_STRING(orig, entry, device, err);
> +	DUP_STRING(orig, entry, trans, err);
>  
>  	entry->dev_type = dup_value_list(orig->dev_type);
> +	if (orig->dev_type && !(entry->dev_type))
> +		goto err;
> +
>  	entry->opts = dup_value_list(orig->opts);
> +	if (orig->opts && !(entry->opts))
> +		goto err;
>  
>  	entry->flags = orig->flags;
>  	entry->inv_flags = orig->inv_flags;
> @@ -492,6 +496,10 @@ struct mnt_entry *dup_mnt_entry(struct m
>  	entry->next = orig->next;
>  
>  	return entry;
> +
> +err:
> +	free_mnt_entry(entry);
> +	return NULL;
>  }
>  
>  void print_mnt_entry(struct mnt_entry *entry)
> Index: b/parser/parser.h
> ===================================================================
> --- a/parser/parser.h
> +++ b/parser/parser.h
> @@ -261,6 +261,13 @@ extern int preprocess_only;
>  		___tmp->next = (LISTB);		\
>  	} while (0)
>  
> +#define DUP_STRING(orig, new, field, fail_target) \
> +	do {									\
> +		(new)->field = ((orig)->field) ? strdup((orig)->field) : NULL;	\
> +		if (((orig)->field) && !((new)->field))				\
> +				goto fail_target;				\
> +	} while (0)
> +
>  /* from parser_common.c */
>  extern int regex_type;
>  extern int perms_create;
> Index: b/parser/parser_misc.c
> ===================================================================
> --- a/parser/parser_misc.c
> +++ b/parser/parser_misc.c
> @@ -840,9 +840,9 @@ struct cod_entry *copy_cod_entry(struct
>  	if (!entry)
>  		return NULL;
>  
> -	entry->namespace = orig->namespace ? strdup(orig->namespace) : NULL;
> -	entry->name = strdup(orig->name);
> -	entry->link_name = orig->link_name ? strdup(orig->link_name) : NULL;
> +	DUP_STRING(orig, entry, namespace, err);
> +	DUP_STRING(orig, entry, name, err);
> +	DUP_STRING(orig, entry, link_name, err);
>  	entry->mode = orig->mode;
>  	entry->audit = orig->audit;
>  	entry->deny = orig->deny;
> @@ -854,6 +854,10 @@ struct cod_entry *copy_cod_entry(struct
>  	entry->next = orig->next;
>  
>  	return entry;
> +
> +err:
> +	free_cod_entries(entry);
> +	return NULL;
>  }
>  
>  void free_cod_entries(struct cod_entry *list)
> 
> 
> -- 
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