old_bits arg is currently a pointer to the input bits, but this could allow inadvertent changes to the input by the fn. Disallow this. And constify new_bits while here. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- lib/dynamic_debug.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 882354e1e78f..d4a0ae31d059 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -597,7 +597,8 @@ static int ddebug_exec_queries(char *query, const char *modname) /* apply a new class-param setting */ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, - unsigned long *new_bits, unsigned long *old_bits, + const unsigned long *new_bits, + const unsigned long old_bits, const char *query_modname) { #define QUERY_SIZE 128 @@ -606,12 +607,12 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, int matches = 0; int bi, ct; - if (*new_bits != *old_bits) + if (*new_bits != old_bits) v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, - *old_bits, query_modname ?: "'*'"); + old_bits, query_modname ?: "'*'"); for (bi = 0; bi < map->length; bi++) { - if (test_bit(bi, new_bits) == test_bit(bi, old_bits)) + if (test_bit(bi, new_bits) == test_bit(bi, &old_bits)) continue; snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi], @@ -623,9 +624,9 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, ct, map->class_names[bi], *new_bits); } - if (*new_bits != *old_bits) + if (*new_bits != old_bits) v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, - *old_bits, query_modname ?: "'*'"); + old_bits, query_modname ?: "'*'"); return matches; } @@ -681,7 +682,7 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa continue; } curr_bits ^= BIT(cls_id); - totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits, NULL); + totct += ddebug_apply_class_bitmap(dcp, &curr_bits, *dcp->bits, NULL); *dcp->bits = curr_bits; v2pr_info("%s: changed bit %d:%s\n", KP_NAME(kp), cls_id, map->class_names[cls_id]); @@ -691,7 +692,7 @@ static int param_set_dyndbg_classnames(const char *instr, const struct kernel_pa old_bits = CLASSMAP_BITMASK(*dcp->lvl); curr_bits = CLASSMAP_BITMASK(cls_id + (wanted ? 1 : 0 )); - totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits, NULL); + totct += ddebug_apply_class_bitmap(dcp, &curr_bits, old_bits, NULL); *dcp->lvl = (cls_id + (wanted ? 1 : 0)); v2pr_info("%s: changed bit-%d: \"%s\" %lx->%lx\n", KP_NAME(kp), cls_id, map->class_names[cls_id], old_bits, curr_bits); @@ -745,7 +746,7 @@ static int param_set_dyndbg_module_classes(const char *instr, inrep &= CLASSMAP_BITMASK(map->length); } v2pr_info("bits:0x%lx > %s.%s\n", inrep, modnm ?: "*", KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, modnm); + totct += ddebug_apply_class_bitmap(dcp, &inrep, *dcp->bits, modnm); *dcp->bits = inrep; break; case DD_CLASS_TYPE_LEVEL_NUM: @@ -758,7 +759,7 @@ static int param_set_dyndbg_module_classes(const char *instr, old_bits = CLASSMAP_BITMASK(*dcp->lvl); new_bits = CLASSMAP_BITMASK(inrep); v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, modnm); + totct += ddebug_apply_class_bitmap(dcp, &new_bits, old_bits, modnm); *dcp->lvl = inrep; break; default: -- 2.45.2