* Qian Cai <quic_qiancai@xxxxxxxxxxx> [220427 16:22]: > On Wed, Apr 27, 2022 at 04:51:50PM +0000, Liam Howlett wrote: > > Thanks. This is indeed an issue with 0d43186b36c1 (mm/mlock: use vma > > iterator and instead of vma linked list) > > > > Andrew, Please include this patch as a fix. > > Even with the patch applied, there are still thousands of memory leaks > reports from kmemleak after booting. Thank you for finding this. > > unreferenced object 0xffff400259bd6d00 (size 256): > comm "multipathd", pid 2577, jiffies 4294915929 (age 2370.384s) > hex dump (first 32 bytes): > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > slab_post_alloc_hook > kmem_cache_alloc_bulk > mas_alloc_nodes > mt_alloc_bulk at lib/maple_tree.c:151 > (inlined by) mas_alloc_nodes at lib/maple_tree.c:1244 > mas_preallocate > __vma_adjust > shift_arg_pages > setup_arg_pages > load_elf_binary > search_binary_handler > exec_binprm > bprm_execve > do_execveat_common.isra.0 > __arm64_sys_execve > invoke_syscall > el0_svc_common.constprop.0 > do_el0_svc __vma_adjust is way too complicated. This patch should fix the leak. Andrew, please add this patch to "mm: start tracking VMAs with maple tree" Thanks, Liam
From 74f551227d44b351d56f4ec0a36542d871f337d5 Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx> Date: Wed, 27 Apr 2022 18:40:00 -0400 Subject: [PATCH] mm/mmap: Fix __vma_adjust() memory leak. When shifting the arg pages, the maple state may be left with allocated memory. Free the memory by calling mas_destroy() unconditionally at the end of the function. Fixes: bd6a1fd58daf (mm: start tracking VMAs with maple tree) Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> --- mm/mmap.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/mmap.c b/mm/mmap.c index 6a37f5d2e496..f52bbf9aa024 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -904,6 +904,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, uprobe_mmap(insert); } + mas_destroy(&mas); validate_mm(mm); return 0; -- 2.35.1
