From a5544880aff90baf1bd4443ac7ff65182213ffcd Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Fri, 10 Feb 2017 14:06:22 -0800 Subject: [PATCH] module: fix memory leak on early load_module() failures While looking for early possible module loading failures I was able to reproduce a memory leak possible with kmemleak. There are a few rare ways to trigger a failure: o we've run into a failure while processing kernel parameters (parse_args() returns an error) o mod_sysfs_setup() fails o we're a live patch module and copy_module_elf() fails Chances of running into this issue is really low. kmemleak splat: unreferenced object 0xffff9f2c4ada1b00 (size 32): comm "kworker/u16:4", pid 82, jiffies 4294897636 (age 681.816s) hex dump (first 32 bytes): 6d 65 6d 73 74 69 63 6b 30 00 00 00 00 00 00 00 memstick0....... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x4a/0xa0 [] __kmalloc_track_caller+0x126/0x230 [] kstrdup+0x31/0x60 [] kstrdup_const+0x24/0x30 [] kvasprintf_const+0x7a/0x90 [] kobject_set_name_vargs+0x21/0x90 [] dev_set_name+0x47/0x50 [] memstick_check+0x95/0x33c [memstick] [] process_one_work+0x1f3/0x4b0 [] worker_thread+0x48/0x4e0 [] kthread+0xc9/0xe0 [] ret_from_fork+0x1f/0x40 [] 0xffffffffffffffff Cc: stable # v2.6.30 Fixes: e180a6b7759a ("param: fix charp parameters set via sysfs") Reviewed-by: Miroslav Benes Reviewed-by: Aaron Tomlin Reviewed-by: Rusty Russell Acked-by: Kees Cook Signed-off-by: Luis R. Rodriguez Signed-off-by: Jessica Yu --- kernel/module.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/module.c b/kernel/module.c index 32d0d32abbf6..14da88b5d0fb 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3724,6 +3724,7 @@ static int load_module(struct load_info *info, const char __user *uargs, mod_sysfs_teardown(mod); coming_cleanup: mod->state = MODULE_STATE_GOING; + destroy_params(mod->kp, mod->num_kp); blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); klp_module_going(mod); -- 2.30.2