On Tue, Jun 04, 2019 at 07:21:16PM -0400, Sasha Levin wrote: > From: Venkata Narendra Kumar Gutta <vnkgutta@xxxxxxxxxxxxxx> > > [ Upstream commit edb16da34b084c66763f29bee42b4e6bb33c3d66 ] > > Platform core is using pdev->name as the platform device name to do > the binding of the devices with the drivers. But, when the platform > driver overrides the platform device name with dev_set_name(), > the pdev->name is pointing to a location which is freed and becomes > an invalid parameter to do the binding match. > > use-after-free instance: > > [ 33.325013] BUG: KASAN: use-after-free in strcmp+0x8c/0xb0 > [ 33.330646] Read of size 1 at addr ffffffc10beae600 by task modprobe > [ 33.339068] CPU: 5 PID: 518 Comm: modprobe Tainted: > G S W O 4.19.30+ #3 > [ 33.346835] Hardware name: MTP (DT) > [ 33.350419] Call trace: > [ 33.352941] dump_backtrace+0x0/0x3b8 > [ 33.356713] show_stack+0x24/0x30 > [ 33.360119] dump_stack+0x160/0x1d8 > [ 33.363709] print_address_description+0x84/0x2e0 > [ 33.368549] kasan_report+0x26c/0x2d0 > [ 33.372322] __asan_report_load1_noabort+0x2c/0x38 > [ 33.377248] strcmp+0x8c/0xb0 > [ 33.380306] platform_match+0x70/0x1f8 > [ 33.384168] __driver_attach+0x78/0x3a0 > [ 33.388111] bus_for_each_dev+0x13c/0x1b8 > [ 33.392237] driver_attach+0x4c/0x58 > [ 33.395910] bus_add_driver+0x350/0x560 > [ 33.399854] driver_register+0x23c/0x328 > [ 33.403886] __platform_driver_register+0xd0/0xe0 > > So, use dev_name(&pdev->dev), which fetches the platform device name from > the kobject(dev->kobj->name) of the device instead of the pdev->name. > > Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@xxxxxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> > --- > drivers/base/platform.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) Please drop this from everywhere as it was reverted from Linus's tree because it causes big problems. thanks, greg k-h