From 011d8de504bc84402aabc1dda1cf0552fe9a5af2 Mon Sep 17 00:00:00 2001 From: Kostas Damaskinakis Date: Fri, 10 Jul 2026 17:15:20 +0300 Subject: [PATCH] clk: eswin: Zero-initialize stack-allocated clk_init_data 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 [] __clk_register+0x31a/0x7f0 [] devm_clk_hw_register+0x2a/0x94 [] eswin_register_clkdiv+0x80/0xd0 [] eswin_clk_register_clks+0x162/0x1a0 [] eic7700_clk_probe+0x146/0x180 [] 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: cd44f127c1d4 ("clk: eswin: Add eic7700 clock driver") Signed-off-by: Kostas Damaskinakis Reviewed-by: Brian Masney Acked-by: Xuyang Dong Signed-off-by: Brian Masney --- drivers/clk/eswin/clk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/clk/eswin/clk.c b/drivers/clk/eswin/clk.c index e09a52cc3587..79d1e4c5e637 100644 --- a/drivers/clk/eswin/clk.c +++ b/drivers/clk/eswin/clk.c @@ -204,7 +204,7 @@ int eswin_clk_register_pll(struct device *dev, struct eswin_pll_clock *clks, int nums, struct eswin_clock_data *data) { struct eswin_clk_pll *p_clk = NULL; - struct clk_init_data init; + struct clk_init_data init = {}; struct clk_hw *clk_hw; int i, ret; @@ -419,7 +419,7 @@ struct clk_hw *eswin_register_clkdiv(struct device *dev, unsigned int id, unsigned long priv_flag, spinlock_t *lock) { struct eswin_divider_clock *dclk; - struct clk_init_data init; + struct clk_init_data init = {}; struct clk_hw *clk_hw; int ret;