From 0e9f090a4e9bfae5a190ccf89eab3bf14f6b0f96 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Fri, 27 Mar 2026 12:00:04 +0100 Subject: [PATCH] module/kallsyms: fix nextval for data symbol lookup The symbol lookup code assumes the queried address resides in either MOD_TEXT or MOD_INIT_TEXT. This breaks for addresses in other module memory regions (e.g. rodata or data), resulting in incorrect upper bounds and wrong symbol size. Select the module memory region the address belongs to instead of hardcoding text sections. Also initialize the lower bound to the start of that region, as searching from address 0 is unnecessary. Cc: stable@vger.kernel.org Signed-off-by: Stanislaw Gruszka Reviewed-by: Petr Pavlu Signed-off-by: Petr Pavlu --- kernel/module/kallsyms.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c index 0fc11e45df9b..f23126d804b2 100644 --- a/kernel/module/kallsyms.c +++ b/kernel/module/kallsyms.c @@ -258,17 +258,25 @@ static const char *find_kallsyms_symbol(struct module *mod, unsigned int i, best = 0; unsigned long nextval, bestval; struct mod_kallsyms *kallsyms = rcu_dereference(mod->kallsyms); - struct module_memory *mod_mem; + struct module_memory *mod_mem = NULL; - /* At worse, next value is at end of module */ - if (within_module_init(addr, mod)) - mod_mem = &mod->mem[MOD_INIT_TEXT]; - else - mod_mem = &mod->mem[MOD_TEXT]; + for_each_mod_mem_type(type) { +#ifndef CONFIG_KALLSYMS_ALL + if (!mod_mem_type_is_text(type)) + continue; +#endif + if (within_module_mem_type(addr, mod, type)) { + mod_mem = &mod->mem[type]; + break; + } + } + if (!mod_mem) + return NULL; + + /* Initialize bounds within memory region the address belongs to. */ nextval = (unsigned long)mod_mem->base + mod_mem->size; - - bestval = kallsyms_symbol_value(&kallsyms->symtab[best]); + bestval = (unsigned long)mod_mem->base - 1; /* * Scan for closest preceding symbol, and next symbol. (ELF