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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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From: Murphy Zhou <jencce.kernel@gmail.com>
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Date: Sun, 29 Sep 2019 17:56:59 +0800
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Subject: [PATCH] mm/kmemleak: skip late_init if not skip disable
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Now if DEFAULT_OFF set to y, kmemleak_init will start the cleanup_work
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workqueue. Then late_init call will set kmemleak_initialized to 1, the
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cleaup workqueue will try to do cleanup, triggering:
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[24.738773] ==================================================================
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[24.742784] BUG: KASAN: global-out-of-bounds in __kmemleak_do_cleanup+0x166/0x180
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[24.744144] Key type ._fscrypt registered
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[24.745680] Read of size 8 at addr ffffffff88746c90 by task kworker/3:1/171
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[24.745687]
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[24.745697] CPU: 3 PID: 171 Comm: kworker/3:1 Not tainted 5.3.0-v5.3-12475-gcbafe18 #1
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[24.745701] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
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[24.745710] Workqueue: events kmemleak_do_cleanup
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[24.745717] Call Trace:
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[24.745736]  dump_stack+0x7c/0xc0
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[24.745755]  print_address_description.constprop.4+0x1f/0x300
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[24.751562] Key type .fscrypt registered
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[24.754370]  __kasan_report.cold.8+0x76/0xb2
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[24.754388]  ? __kmemleak_do_cleanup+0x166/0x180
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[24.754407]  kasan_report+0xe/0x20
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[24.778543]  __kmemleak_do_cleanup+0x166/0x180
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[24.780795]  process_one_work+0x919/0x17d0
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[24.782929]  ? pwq_dec_nr_in_flight+0x320/0x320
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[24.785092]  worker_thread+0x87/0xb40
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[24.786948]  ? __kthread_parkme+0xc3/0x190
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[24.789217]  ? process_one_work+0x17d0/0x17d0
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[24.791414]  kthread+0x333/0x3f0
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[24.793031]  ? kthread_create_worker_on_cpu+0xc0/0xc0
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[24.795473]  ret_from_fork+0x3a/0x50
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[24.797303]
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[24.798091] The buggy address belongs to the variable:
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[24.800634]  mem_pool_free_count+0x10/0x40
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[24.802656]
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[24.803434] Memory state around the buggy address:
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[24.805793]  ffffffff88746b80: 04 fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
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[24.809177]  ffffffff88746c00: 00 fa fa fa fa fa fa fa 00 00 fa fa fa fa fa fa
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[24.812407] >ffffffff88746c80: 04 fa fa fa fa fa fa fa 00 00 fa fa fa fa fa fa
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[24.815638]                          ^
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[24.817372]  ffffffff88746d00: 00 00 fa fa fa fa fa fa 00 00 00 00 00 00 00 00
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[24.820740]  ffffffff88746d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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[24.824021] ==================================================================
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Fixes: c5665868183f ("mm: kmemleak: use the memory pool for early allocations")
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Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
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---
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 mm/kmemleak.c | 5 +++++
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 1 file changed, 5 insertions(+)
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diff --git a/mm/kmemleak.c b/mm/kmemleak.c
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index e362dc3d2028..0c3dfb8eef67 100644
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--- a/mm/kmemleak.c
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+++ b/mm/kmemleak.c
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@@ -1958,6 +1958,11 @@ void __init kmemleak_init(void)
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  */
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 static int __init kmemleak_late_init(void)
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 {
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+	if (!kmemleak_skip_disable) {
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+		kmemleak_disable();
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+		return 0;
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+	}
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+
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 	kmemleak_initialized = 1;
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 	debugfs_create_file("kmemleak", 0644, NULL, NULL, &kmemleak_fops);
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-- 
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2.28.0
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