When list_prepend() returns an error, it always means it failed to allocate some memory and does not hold any reference to its argument data. This argument needs to be freed by the caller in order to prevent a memory leak. While reviewing list_prepend() callers, I spend quite some time understanding why typealiases_gather_map() does not need to strdup(key) or free(key) when calling list_prepend(..., key) even though "key" comes from pdb->p_types.table: because typealias_list_destroy() does not free the inserted items. Add a comment to make this clearer in the code. Signed-off-by: Nicolas Iooss <nicolas.iooss@xxxxxxx> --- libsepol/src/module_to_cil.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/libsepol/src/module_to_cil.c b/libsepol/src/module_to_cil.c index c6f1659c84ef..ba8311ea7c75 100644 --- a/libsepol/src/module_to_cil.c +++ b/libsepol/src/module_to_cil.c @@ -298,6 +298,8 @@ static int roles_gather_map(char *key, void *data, void *args) role_node->role = role; rc = list_prepend((struct list *)args, role_node); + if (rc != 0) + free(role_node); return rc; } @@ -344,6 +346,11 @@ static int typealiases_gather_map(char *key, void *data, void *arg) goto exit; } } + /* As typealias_lists[scope_id] does not hold the + * ownership of its items (typealias_list_destroy does + * not free the list items), "key" does not need to be + * strdup'ed before it is inserted in the list. + */ list_prepend(typealias_lists[scope_id], key); } } -- 2.17.0 _______________________________________________ Selinux mailing list Selinux@xxxxxxxxxxxxx To unsubscribe, send email to Selinux-leave@xxxxxxxxxxxxx. To get help, send an email containing "help" to Selinux-request@xxxxxxxxxxxxx.
