Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967950AbWK3XA6 (ORCPT ); Thu, 30 Nov 2006 18:00:58 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S967951AbWK3XA5 (ORCPT ); Thu, 30 Nov 2006 18:00:57 -0500 Received: from mtaout03-winn.ispmail.ntl.com ([81.103.221.49]:59218 "EHLO mtaout03-winn.ispmail.ntl.com") by vger.kernel.org with ESMTP id S967950AbWK3XAh (ORCPT ); Thu, 30 Nov 2006 18:00:37 -0500 From: Catalin Marinas Subject: [PATCH 2.6.19 04/10] Modules support for kmemleak To: linux-kernel@vger.kernel.org Date: Thu, 30 Nov 2006 23:00:32 +0000 Message-ID: <20061130230032.5469.23092.stgit@localhost.localdomain> In-Reply-To: <20061130225219.5469.2453.stgit@localhost.localdomain> References: <20061130225219.5469.2453.stgit@localhost.localdomain> User-Agent: StGIT/0.11 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4329 Lines: 130 This patch handles the kmemleak operations needed for modules loading so that memory allocations from inside a module are properly tracked. Signed-off-by: Catalin Marinas --- kernel/module.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 56 insertions(+), 0 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index f016656..b2b9526 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -345,6 +345,7 @@ static void *percpu_modalloc(unsigned lo unsigned long extra; unsigned int i; void *ptr; + int cpu; if (align > SMP_CACHE_BYTES) { printk(KERN_WARNING "%s: per-cpu alignment %li > %i\n", @@ -374,6 +375,10 @@ static void *percpu_modalloc(unsigned lo if (!split_block(i, size)) return NULL; + /* add the per-cpu scanning areas */ + for_each_possible_cpu(cpu) + memleak_alloc(ptr + per_cpu_offset(cpu), size, 0); + /* Mark allocated */ pcpu_size[i] = -pcpu_size[i]; return ptr; @@ -388,6 +393,7 @@ static void percpu_modfree(void *freeme) { unsigned int i; void *ptr = __per_cpu_start + block_size(pcpu_size[0]); + int cpu; /* First entry is core kernel percpu data. */ for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { @@ -399,6 +405,10 @@ static void percpu_modfree(void *freeme) BUG(); free: + /* remove the per-cpu scanning areas */ + for_each_possible_cpu(cpu) + memleak_free(freeme + per_cpu_offset(cpu)); + /* Merge with previous? */ if (pcpu_size[i-1] >= 0) { pcpu_size[i-1] += pcpu_size[i]; @@ -1477,6 +1487,42 @@ static inline void add_kallsyms(struct m } #endif /* CONFIG_KALLSYMS */ +#ifdef CONFIG_DEBUG_MEMLEAK +static void memleak_load_module(struct module *mod, Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, char *secstrings) +{ + unsigned int mloffindex, i; + + /* insert any new pointer aliases */ + mloffindex = find_sec(hdr, sechdrs, secstrings, ".init.memleak_offsets"); + if (mloffindex) + memleak_insert_aliases((void *)sechdrs[mloffindex].sh_addr, + (void *)sechdrs[mloffindex].sh_addr + + sechdrs[mloffindex].sh_size); + + /* only scan the sections containing data */ + memleak_scan_area(mod->module_core, + (unsigned long)mod - (unsigned long)mod->module_core, + sizeof(struct module)); + + for (i = 1; i < hdr->e_shnum; i++) { + if (!(sechdrs[i].sh_flags & SHF_ALLOC)) + continue; + if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0 + && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0) + continue; + + memleak_scan_area(mod->module_core, + sechdrs[i].sh_addr - (unsigned long)mod->module_core, + sechdrs[i].sh_size); + } +} +#else +static inline void memleak_load_module(struct module *mod, Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, char *secstrings) +{ } +#endif + /* Allocate and load the module: note that size of section 0 is always zero, and we rely on this for optional sections. */ static struct module *load_module(void __user *umod, @@ -1672,6 +1718,10 @@ static struct module *load_module(void _ /* Do the allocs. */ ptr = module_alloc(mod->core_size); + /* the pointer to this block is stored in the module structure + * which is inside the block. Just mark it as not being a + * leak */ + memleak_not_leak(ptr); if (!ptr) { err = -ENOMEM; goto free_percpu; @@ -1680,6 +1730,11 @@ static struct module *load_module(void _ mod->module_core = ptr; ptr = module_alloc(mod->init_size); + /* the pointer to this block is stored in the module structure + * which is inside the block. This block doesn't need to be + * scanned as it contains data and code that will be freed + * after the module is initialized */ + memleak_ignore(ptr); if (!ptr && mod->init_size) { err = -ENOMEM; goto free_core; @@ -1710,6 +1765,7 @@ static struct module *load_module(void _ } /* Module has been moved. */ mod = (void *)sechdrs[modindex].sh_addr; + memleak_load_module(mod, hdr, sechdrs, secstrings); /* Now we've moved module, initialize linked lists, etc. */ module_unload_init(mod); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/