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| author | Pavel Skripkin <paskripkin@gmail.com> | 2021-08-04 17:30:05 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-08-05 17:29:24 +0300 |
| commit | af35fc37354cda3c9c8cc4961b1d24bdc9d27903 (patch) | |
| tree | e4273c449c8b000e0a3bcbd7e1aaecec60a2881d /drivers | |
| parent | ae03d189bae306e1e00aa631feee090ebda6cf63 (diff) | |
| download | linux-af35fc37354cda3c9c8cc4961b1d24bdc9d27903.tar.xz | |
net: pegasus: fix uninit-value in get_interrupt_interval
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@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Link: https://lore.kernel.org/r/20210804143005.439-1-paskripkin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/usb/pegasus.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/net/usb/pegasus.c b/drivers/net/usb/pegasus.c index f18b03be1b87..652e9fcf0b77 100644 --- a/drivers/net/usb/pegasus.c +++ b/drivers/net/usb/pegasus.c @@ -744,12 +744,16 @@ static inline void disable_net_traffic(pegasus_t *pegasus) set_registers(pegasus, EthCtrl0, sizeof(tmp), &tmp); } -static inline void get_interrupt_interval(pegasus_t *pegasus) +static inline int get_interrupt_interval(pegasus_t *pegasus) { u16 data; u8 interval; + int ret; + + ret = read_eprom_word(pegasus, 4, &data); + if (ret < 0) + return ret; - read_eprom_word(pegasus, 4, &data); interval = data >> 8; if (pegasus->usb->speed != USB_SPEED_HIGH) { if (interval < 0x80) { @@ -764,6 +768,8 @@ static inline void get_interrupt_interval(pegasus_t *pegasus) } } pegasus->intr_interval = interval; + + return 0; } static void set_carrier(struct net_device *net) @@ -1165,7 +1171,9 @@ static int pegasus_probe(struct usb_interface *intf, | NETIF_MSG_PROBE | NETIF_MSG_LINK); pegasus->features = usb_dev_id[dev_index].private; - get_interrupt_interval(pegasus); + res = get_interrupt_interval(pegasus); + if (res) + goto out2; if (reset_mac(pegasus)) { dev_err(&intf->dev, "can't reset MAC\n"); res = -EIO; |