From: Yuan Can yuancan@huawei.com
[ Upstream commit 0d0b368b9d104b437e1f4850ae94bdb9a3601e89 ]
A memory leak was reported after the vkms module install failed.
unreferenced object 0xffff88810bc28520 (size 16): comm "modprobe", pid 9662, jiffies 4298009455 (age 42.590s) hex dump (first 16 bytes): 01 01 00 64 81 88 ff ff 00 00 dc 0a 81 88 ff ff ...d............ backtrace: [<00000000e7561ff8>] kmalloc_trace+0x27/0x60 [<000000000b1954a0>] 0xffffffffc45200a9 [<00000000abbf1da0>] do_one_initcall+0xd0/0x4f0 [<000000001505ee87>] do_init_module+0x1a4/0x680 [<00000000958079ad>] load_module+0x6249/0x7110 [<00000000117e4696>] __do_sys_finit_module+0x140/0x200 [<00000000f74b12d2>] do_syscall_64+0x35/0x80 [<000000008fc6fcde>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
The reason is that the vkms_init() returns without checking the return value of vkms_create(), and if the vkms_create() failed, the config allocated at the beginning of vkms_init() is leaked.
vkms_init() config = kmalloc(...) # config allocated ... return vkms_create() # vkms_create failed and config is leaked
Fix this problem by checking return value of vkms_create() and free the config if error happened.
Fixes: 2df7af93fdad ("drm/vkms: Add vkms_config type") Signed-off-by: Yuan Can yuancan@huawei.com Reviewed-by: Melissa Wen mwen@igalia.com Signed-off-by: Melissa Wen melissa.srw@gmail.com Link: https://patchwork.freedesktop.org/patch/msgid/20221101065156.41584-2-yuancan... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/vkms/vkms_drv.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c index 293dbca50c316..8a74f37d59123 100644 --- a/drivers/gpu/drm/vkms/vkms_drv.c +++ b/drivers/gpu/drm/vkms/vkms_drv.c @@ -218,6 +218,7 @@ static int vkms_create(struct vkms_config *config)
static int __init vkms_init(void) { + int ret; struct vkms_config *config;
config = kmalloc(sizeof(*config), GFP_KERNEL); @@ -230,7 +231,11 @@ static int __init vkms_init(void) config->writeback = enable_writeback; config->overlay = enable_overlay;
- return vkms_create(config); + ret = vkms_create(config); + if (ret) + kfree(config); + + return ret; }
static void vkms_destroy(struct vkms_config *config)