Fix: Filter: Fix allocation length error

Was causing generation of corrupted filter bytecode.

Fixes #351,#344

Signed-off-by: Christian Babeux <christian.babeux@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/src/lib/lttng-ctl/filter/filter-visitor-generate-bytecode.c b/src/lib/lttng-ctl/filter/filter-visitor-generate-bytecode.c
index 8d44f4b7ec29d3b66cde39158711abeb558db135..52c69567c37422b1039c544185b7289a3433eff4 100644 (file)
--- a/src/lib/lttng-ctl/filter/filter-visitor-generate-bytecode.c
+++ b/src/lib/lttng-ctl/filter/filter-visitor-generate-bytecode.c
@@ -80,11 +80,14 @@ static inline int get_count_order(unsigned int count)
 static
 int bytecode_init(struct lttng_filter_bytecode_alloc **fb)
 {
-       *fb = calloc(sizeof(struct lttng_filter_bytecode_alloc) + INIT_ALLOC_SIZE, 1);
+       uint32_t alloc_len;
+
+       alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + INIT_ALLOC_SIZE;
+       *fb = calloc(alloc_len, 1);
        if (!*fb) {
                return -ENOMEM;
        } else {
-               (*fb)->alloc_len = INIT_ALLOC_SIZE;
+               (*fb)->alloc_len = alloc_len;
                return 0;
        }
 }
@@ -95,7 +98,7 @@ int32_t bytecode_reserve(struct lttng_filter_bytecode_alloc **fb, uint32_t align
        int32_t ret;
        uint32_t padding = offset_align((*fb)->b.len, align);
        uint32_t new_len = (*fb)->b.len + padding + len;
-       uint32_t new_alloc_len = sizeof(struct lttng_filter_bytecode) + new_len;
+       uint32_t new_alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + new_len;
        uint32_t old_alloc_len = (*fb)->alloc_len;
 
        if (new_len > LTTNG_FILTER_MAX_LEN)
@@ -107,6 +110,7 @@ int32_t bytecode_reserve(struct lttng_filter_bytecode_alloc **fb, uint32_t align
                *fb = realloc(*fb, new_alloc_len);
                if (!*fb)
                        return -ENOMEM;
+               /* We zero directly the memory from start of allocation. */
                memset(&((char *) *fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len);
                (*fb)->alloc_len = new_alloc_len;
        }