Validate the filter chain before checking filter-specific

memory usage.

diff --git a/src/liblzma/common/filter_common.c b/src/liblzma/common/filter_common.c
index 03b6859..13a7cdd 100644 (file)
--- a/src/liblzma/common/filter_common.c
+++ b/src/liblzma/common/filter_common.c
@@ -227,8 +227,11 @@ lzma_memusage_coder(lzma_filter_find coder_find,
                const lzma_filter *filters)
 {
        // The chain has to have at least one filter.
-       if (filters[0].id == LZMA_VLI_UNKNOWN)
-               return UINT64_MAX;
+       {
+               size_t tmp;
+               if (validate_chain(filters, &tmp) != LZMA_OK)
+                       return UINT64_MAX;
+       }
 
        uint64_t total = 0;
        size_t i = 0;
@@ -241,8 +244,11 @@ lzma_memusage_coder(lzma_filter_find coder_find,
 
                if (fc->memusage == NULL) {
                        // This filter doesn't have a function to calculate
-                       // the memory usage. Such filters need only little
-                       // memory, so we use 1 KiB as a good estimate.
+                       // the memory usage and validate the options. Such
+                       // filters need only little memory, so we use 1 KiB
+                       // as a good estimate. They also accept all possible
+                       // options, so there's no need to worry about lack
+                       // of validation.
                        total += 1024;
                } else {
                        // Call the filter-specific memory usage calculation