Ilkka Lappeteläinen 2cf81fc950 net/packet: prevent TX_RING byte count overflow ... tpacket_snd() drains every SEND_REQUEST frame in a TX ring and adds each valid packet length to the signed int len_sum. Userspace can recycle completed frames concurrently, so a single blocking send call is not bounded by the ring size. After enough successful transmissions len_sum wraps into the negative range. In particular, 65536 65535-byte frames followed by a 65007-byte frame produce 0xfffffdef, or -EIOCBQUEUED. sock_sendmsg_nosec() treats that as an impossible return and triggers a BUG. On systems configured to panic on oops, a CAP_NET_RAW holder can panic the host kernel. Stop before the next frame would make the byte count exceed INT_MAX. The positive short count leaves that frame pending for a later send call. A two-thread TPACKET_V2 reproducer triggered the BUG on an arm64 build of Linux 7.3-rc4. With this change, the same reproducer returned the expected positive short count without an oops. Fixes: 69e3c75f4d ("net: TX_RING and packet mmap") Cc: stable@vger.kernel.org Signed-off-by: Ilkka Lappeteläinen <ilkka.lappetelainen@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260925124829.6595-1-ilkka.lappetelainen@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2026-09-29 16:30:17 -07:00
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af_packet.c	net/packet: prevent TX_RING byte count overflow	2026-09-29 16:30:17 -07:00
diag.c	net: change sock.sk_ino and sock_i_ino() to u64	2026-03-06 14:31:26 +01:00
internal.h	net/packet: avoid truncating TPACKET_V3 private size	2026-09-16 17:29:11 -07:00
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