diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-04-11 14:01:35 +0300 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2026-04-14 13:05:01 +0300 |
| commit | 600dc40554dc5ad1e6f3af51f700228033f43ea7 (patch) | |
| tree | f851b33ff82650ee35af64aff6b2471681c9639a | |
| parent | ab4b6e4e80a0e573bd77d69439e4cb55e9e3c5ee (diff) | |
| download | linux-600dc40554dc5ad1e6f3af51f700228033f43ea7.tar.xz | |
net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()
A malicious USB device claiming to be a CDC Phonet modem can overflow
the skb_shared_info->frags[] array by sending an unbounded sequence of
full-page bulk transfers.
Drop the skb and increment the length error when the frag limit is
reached. This matches the same fix that commit f0813bcd2d9d ("net:
wwan: t7xx: fix potential skb->frags overflow in RX path") did for the
t7xx driver.
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: stable <stable@kernel.org>
Assisted-by: gregkh_clanker_t1000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2026041134-dreamboat-buddhism-d1ec@gregkh
Fixes: 87cf65601e17 ("USB host CDC Phonet network interface driver")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | drivers/net/usb/cdc-phonet.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/net/usb/cdc-phonet.c b/drivers/net/usb/cdc-phonet.c index ad5121e9cf5d..165650ecef64 100644 --- a/drivers/net/usb/cdc-phonet.c +++ b/drivers/net/usb/cdc-phonet.c @@ -157,11 +157,16 @@ static void rx_complete(struct urb *req) PAGE_SIZE); page = NULL; } - } else { + } else if (skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) { skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, 0, req->actual_length, PAGE_SIZE); page = NULL; + } else { + dev_kfree_skb_any(skb); + pnd->rx_skb = NULL; + skb = NULL; + dev->stats.rx_length_errors++; } if (req->actual_length < PAGE_SIZE) pnd->rx_skb = NULL; /* Last fragment */ |