On Wed, Jul 16, 2025 at 05:06:38AM GMT, Paul Menzel wrote: > Dear Ivan, > > > Thank you for your patch and fixing the report. > > Am 16.07.25 um 02:37 schrieb Ivan Pravdin: > > Personally, I’d start with the problem description. I will add more details in v3. > > > Create and use new vmalloc'ed buffer with dev_coredumpv. From > > dev_coredumpv documentation: > > > > `This function takes ownership of the vmalloc'ed data and will free > > it when it is no longer used.` > > You could use email/Markdown style citation by prepending the lines with `> `. I will fix it in v3. > > > As hdev->dump is used after dev_coredumpv, create temporary buffer to > > hold hdev->dump data. > > > > Reported-by: syzbot+ac3c79181f6aecc5120c@xxxxxxxxxxxxxxxxxxxxxxxxx > > Closes: https://lore.kernel.org/all/67eaa688.050a0220.1547ec.014a.GAE@xxxxxxxxxx > > Add a trace excerpt to the commit message? I will add it in v3. > > > Fixes: b257e02ecc46 ("HCI: coredump: Log devcd dumps into the monitor") > > Signed-off-by: Ivan Pravdin <ipravdin.official@xxxxxxxxx> > > --- > > v1 -> v2: Changed subject prefix to Bluetooth: > > > > net/bluetooth/coredump.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/net/bluetooth/coredump.c b/net/bluetooth/coredump.c > > index 819eacb38762..1232c9a94f95 100644 > > --- a/net/bluetooth/coredump.c > > +++ b/net/bluetooth/coredump.c > > @@ -243,6 +243,7 @@ static void hci_devcd_handle_pkt_pattern(struct hci_dev *hdev, > > static void hci_devcd_dump(struct hci_dev *hdev) > > { > > struct sk_buff *skb; > > + char *coredump; > > u32 size; > > bt_dev_dbg(hdev, "state %d", hdev->dump.state); > > @@ -250,7 +251,11 @@ static void hci_devcd_dump(struct hci_dev *hdev) > > size = hdev->dump.tail - hdev->dump.head; > > /* Emit a devcoredump with the available data */ > > - dev_coredumpv(&hdev->dev, hdev->dump.head, size, GFP_KERNEL); > > + coredump = vmalloc(size); > > + if (coredump) { > > + memcpy(coredump, hdev->dump.head, size); > > + dev_coredumpv(&hdev->dev, coredump, size, GFP_KERNEL); > > + } > > Should it be logged, if allocation fails? Right, I will add it in v3. > > > /* Send a copy to monitor as a diagnostic packet */ > > skb = bt_skb_alloc(size, GFP_ATOMIC); > > > Kind regards, > > Paul Ivan Pravdin
