clk: eswin: Zero-initialize stack-allocated clk_init_data

Browse source

eswin_clk_register_pll() and eswin_register_clkdiv() declare a struct
clk_init_data on the stack and only initialize some of its fields
(parent_data respectively parent_hws). clk_core_populate_parent_map()
checks parent_names first and parent_data second before falling back
to parent_hws, so leftover stack garbage in the uninitialized fields
hijacks parent resolution and the clk core dereferences a bogus
pointer:

  Unable to handle kernel NULL pointer dereference at virtual address 000000000000000c
  Oops [#1]
  epc : __clk_register+0x31a/0x7f0
  [<ffffffff805dc774>] __clk_register+0x31a/0x7f0
  [<ffffffff805dcd76>] devm_clk_hw_register+0x2a/0x94
  [<ffffffff805e319a>] eswin_register_clkdiv+0x80/0xd0
  [<ffffffff805e34a0>] eswin_clk_register_clks+0x162/0x1a0
  [<ffffffff805e3736>] eic7700_clk_probe+0x146/0x180
  [<ffffffff8065d23c>] platform_probe+0x3c/0x7a

Observed on EIC7700 hardware (with the driver backported to a 6.17
tree); whether the bug triggers depends entirely on what the stack
happens to contain when the registration helpers run.

Zero-initialize both structures.

Fixes: cd44f127c1 ("clk: eswin: Add eic7700 clock driver")
Signed-off-by: Kostas Damaskinakis <kostas.damaskinakis@gmail.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Acked-by: Xuyang Dong <dongxuyang@eswincomputing.com>
Signed-off-by: Brian Masney <bmasney@redhat.com>

...

This commit is contained in:

Kostas Damaskinakis 2026-07-10 17:15:20 +03:00 • committed by Brian Masney

parent 540d91480b

commit 011d8de504

1 changed files with 2 additions and 2 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

4

drivers/clk/eswin/clk.c

View file