A text cursor in the tty; LDLS sets net_device.priv_len

The virtual terminals never drew a cursor. Each now paints a steady
block (the cell with its colours swapped), erased before and redrawn
after every output byte, redrawn by a repaint, and hidden by
ESC [ ? 25 l as curses programs ask.

r8169 under LDLS on the TUF A15 got through probe and died in ndo_open
on __fortify_panic. netdev_priv() is `dev->priv` now, a flexible array
counted by net_device.priv_len, and rtl_open's memset of its ring
bookkeeping is bounds-checked against it. The allocator left priv_len
zero, so the driver saw an area of no bytes. It is set from BTF when the
kernel has the member. __fortify_panic also says which check, how many
bytes it had and wanted, and where from.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015f73FesGZGYPkmDvUcj6QX
This commit is contained in:
Nexoniarz 2026-10-25 18:25:30 +01:00
commit 96389ada8f
7 changed files with 86 additions and 5 deletions

View file

@ -83,6 +83,7 @@ extern struct kpi_ctx kpi;
struct kpi_layout {
unsigned int nd_netdev_ops;
unsigned int nd_dev_addr, nd_perm_addr, nd_addr_len;
unsigned int nd_priv_len; // 0 when this kernel has none (before 6.17)
unsigned int nd_mc, nd_uc;
unsigned int nd_tx, nd_num_tx, nd_real_num_tx;
unsigned int nq_size, nq_dev;