On 7/31/21 12:44 AM, Pavel Skripkin wrote:
Syzbot reported uninit value pegasus_probe(). The problem was in missing
error handling.
get_interrupt_interval() internally calls read_eprom_word() which can
fail in some cases. For example: failed to receive usb control message.
These cases should be handled to prevent uninit value bug, since
read_eprom_word() will not initialize passed stack variable in case of
internal failure.
Fail log:
BUG: KMSAN: uninit-value in get_interrupt_interval drivers/net/usb/pegasus.c:746 [inline]
BUG: KMSAN: uninit-value in pegasus_probe+0x10e7/0x4080 drivers/net/usb/pegasus.c:1152
CPU: 1 PID: 825 Comm: kworker/1:1 Not tainted 5.12.0-rc6-syzkaller #0
...
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
__msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
get_interrupt_interval drivers/net/usb/pegasus.c:746 [inline]
pegasus_probe+0x10e7/0x4080 drivers/net/usb/pegasus.c:1152
....
Local variable ----data.i@pegasus_probe created at:
get_interrupt_interval drivers/net/usb/pegasus.c:1151 [inline]
pegasus_probe+0xe57/0x4080 drivers/net/usb/pegasus.c:1152
get_interrupt_interval drivers/net/usb/pegasus.c:1151 [inline]
pegasus_probe+0xe57/0x4080 drivers/net/usb/pegasus.c:1152
Reported-and-tested-by: syzbot+02c9f70f3afae308464a@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
---
drivers/net/usb/pegasus.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
Hi, David and Jakub!
Should I rebase this patch on top of Petko's clean-up patches? :
1. https://git.kernel.org/netdev/net/c/8a160e2e9aeb
2. https://git.kernel.org/netdev/net/c/bc65bacf239d
With regards,
Pavel Skripkin
