From aeca7ff254843d49a8739f07f7dab1341450111d Mon Sep 17 00:00:00 2001 From: ruanjinjie Date: Thu, 10 Nov 2022 16:23:48 +0800 Subject: [PATCH] vdpa_sim: fix possible memory leak in vdpasim_net_init() and vdpasim_blk_init() Inject fault while probing module, if device_register() fails in vdpasim_net_init() or vdpasim_blk_init(), but the refcount of kobject is not decreased to 0, the name allocated in dev_set_name() is leaked. Fix this by calling put_device(), so that name can be freed in callback function kobject_cleanup(). (vdpa_sim_net) unreferenced object 0xffff88807eebc370 (size 16): comm "modprobe", pid 3848, jiffies 4362982860 (age 18.153s) hex dump (first 16 bytes): 76 64 70 61 73 69 6d 5f 6e 65 74 00 6b 6b 6b a5 vdpasim_net.kkk. backtrace: [] __kmalloc_node_track_caller+0x4e/0x150 [] kstrdup+0x33/0x60 [] kobject_set_name_vargs+0x41/0x110 [] dev_set_name+0xab/0xe0 [] device_add+0xe3/0x1a80 [] 0xffffffffa0270013 [] do_one_initcall+0x87/0x2e0 [] do_init_module+0x1ab/0x640 [] load_module+0x5d00/0x77f0 [] __do_sys_finit_module+0x110/0x1b0 [] do_syscall_64+0x35/0x80 [] entry_SYSCALL_64_after_hwframe+0x46/0xb0 (vdpa_sim_blk) unreferenced object 0xffff8881070c1250 (size 16): comm "modprobe", pid 6844, jiffies 4364069319 (age 17.572s) hex dump (first 16 bytes): 76 64 70 61 73 69 6d 5f 62 6c 6b 00 6b 6b 6b a5 vdpasim_blk.kkk. backtrace: [] __kmalloc_node_track_caller+0x4e/0x150 [] kstrdup+0x33/0x60 [] kobject_set_name_vargs+0x41/0x110 [] dev_set_name+0xab/0xe0 [] device_add+0xe3/0x1a80 [] 0xffffffffa0220013 [] do_one_initcall+0x87/0x2e0 [] do_init_module+0x1ab/0x640 [] load_module+0x5d00/0x77f0 [] __do_sys_finit_module+0x110/0x1b0 [] do_syscall_64+0x35/0x80 [] entry_SYSCALL_64_after_hwframe+0x46/0xb0 Fixes: 899c4d187f6a ("vdpa_sim_blk: add support for vdpa management tool") Fixes: a3c06ae158dd ("vdpa_sim_net: Add support for user supported devices") Signed-off-by: ruanjinjie Reviewed-by: Stefano Garzarella Message-Id: <20221110082348.4105476-1-ruanjinjie@huawei.com> Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang --- drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 4 +++- drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c index c6db1a1..f745926 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c @@ -427,8 +427,10 @@ static int __init vdpasim_blk_init(void) int ret; ret = device_register(&vdpasim_blk_mgmtdev); - if (ret) + if (ret) { + put_device(&vdpasim_blk_mgmtdev); return ret; + } ret = vdpa_mgmtdev_register(&mgmt_dev); if (ret) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c index c3cb225..11f5a12 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c @@ -305,8 +305,10 @@ static int __init vdpasim_net_init(void) int ret; ret = device_register(&vdpasim_net_mgmtdev); - if (ret) + if (ret) { + put_device(&vdpasim_net_mgmtdev); return ret; + } ret = vdpa_mgmtdev_register(&mgmt_dev); if (ret) -- 2.7.4