From 1aadf01e5076b9ab6bf294b9622335c651314895 Mon Sep 17 00:00:00 2001 From: Gaosheng Cui Date: Mon, 24 Oct 2022 14:51:09 +0800 Subject: [PATCH] mtd: core: fix possible resource leak in init_mtd() I got the error report while inject fault in init_mtd(): sysfs: cannot create duplicate filename '/devices/virtual/bdi/mtd-0' Call Trace: dump_stack_lvl+0x67/0x83 sysfs_warn_dup+0x60/0x70 sysfs_create_dir_ns+0x109/0x120 kobject_add_internal+0xce/0x2f0 kobject_add+0x98/0x110 device_add+0x179/0xc00 device_create_groups_vargs+0xf4/0x100 device_create+0x7b/0xb0 bdi_register_va.part.13+0x58/0x2d0 bdi_register+0x9b/0xb0 init_mtd+0x62/0x171 [mtd] do_one_initcall+0x6c/0x3c0 do_init_module+0x58/0x222 load_module+0x268e/0x27d0 __do_sys_finit_module+0xd5/0x140 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd kobject_add_internal failed for mtd-0 with -EEXIST, don't try to register things with the same name in the same directory. Error registering mtd class or bdi: -17 If init_mtdchar() fails in init_mtd(), mtd_bdi will not be unregistered, as a result, we can't load the mtd module again, to fix this by calling bdi_unregister(mtd_bdi) after out_procfs label. Fixes: 445caaa20c4d ("mtd: Allocate bdi objects dynamically") Signed-off-by: Gaosheng Cui Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/20221024065109.2050705-1-cuigaosheng1@huawei.com --- drivers/mtd/mtdcore.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index e0193054f8d9..6c4683a5e531 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -2489,6 +2489,7 @@ static int __init init_mtd(void) out_procfs: if (proc_mtd) remove_proc_entry("mtd", NULL); + bdi_unregister(mtd_bdi); bdi_put(mtd_bdi); err_bdi: class_unregister(&mtd_class);