From: Charles Mirabile Date: Mon, 17 Nov 2025 19:03:29 +0000 (-0500) Subject: clk: spacemit: Set clk_hw_onecell_data::num before using flex array X-Git-Tag: v6.19-rc1~58^2~1^3~4 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=23b2d2fb136959fd0a8e309c70be83d9b8841c7e;p=thirdparty%2Flinux.git clk: spacemit: Set clk_hw_onecell_data::num before using flex array When booting with KASAN enabled the following splat is encountered during probe of the k1 clock driver: UBSAN: array-index-out-of-bounds in drivers/clk/spacemit/ccu-k1.c:1044:16 index 0 is out of range for type 'clk_hw *[*]' CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.18.0-rc5+ #1 PREEMPT(lazy) Hardware name: Unknown Unknown Product/Unknown Product, BIOS 2022.10spacemit 10/01/2022 Call Trace: [] dump_backtrace+0x28/0x38 [] show_stack+0x3a/0x50 [] dump_stack_lvl+0x5a/0x80 [] dump_stack+0x18/0x20 [] ubsan_epilogue+0x10/0x48 [] __ubsan_handle_out_of_bounds+0xa6/0xa8 [] k1_ccu_probe+0x37e/0x420 [] platform_probe+0x56/0x98 [] really_probe+0x9e/0x350 [] __driver_probe_device+0x80/0x138 [] driver_probe_device+0x3a/0xd0 [] __driver_attach+0xac/0x1b8 [] bus_for_each_dev+0x6c/0xc8 [] driver_attach+0x26/0x38 [] bus_add_driver+0x13e/0x268 [] driver_register+0x52/0x100 [] __platform_driver_register+0x28/0x38 [] k1_ccu_driver_init+0x22/0x38 [] do_one_initcall+0x62/0x2a0 [] do_initcalls+0x170/0x1a8 [] kernel_init_freeable+0x16a/0x1e0 [] kernel_init+0x2c/0x180 [] ret_from_fork_kernel+0x16/0x1d8 [] ret_from_fork_kernel_asm+0x16/0x18 ---[ end trace ]--- This is bogus and is simply a result of KASAN consulting the `.num` member of the struct for bounds information (as it should due to `__counted_by`) and finding 0 set by kzalloc() because it has not been initialized before the loop that fills in the array. The easy fix is to just move the line that sets `num` to before the loop that fills the array so that KASAN has the information it needs to accurately conclude that the access is valid. Fixes: 1b72c59db0add ("clk: spacemit: Add clock support for SpacemiT K1 SoC") Tested-by: Yanko Kaneti Signed-off-by: Charles Mirabile Reviewed-by: Alex Elder Reviewed-by: Troy Mitchell Reviewed-by: Yixun Lan Signed-off-by: Stephen Boyd --- diff --git a/drivers/clk/spacemit/ccu-k1.c b/drivers/clk/spacemit/ccu-k1.c index f5a9fe6ba1859..4761bc1e3b6e6 100644 --- a/drivers/clk/spacemit/ccu-k1.c +++ b/drivers/clk/spacemit/ccu-k1.c @@ -1018,6 +1018,8 @@ static int spacemit_ccu_register(struct device *dev, if (!clk_data) return -ENOMEM; + clk_data->num = data->num; + for (i = 0; i < data->num; i++) { struct clk_hw *hw = data->hws[i]; struct ccu_common *common; @@ -1044,8 +1046,6 @@ static int spacemit_ccu_register(struct device *dev, clk_data->hws[i] = hw; } - clk_data->num = data->num; - ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clk_data); if (ret) dev_err(dev, "failed to add clock hardware provider (%d)\n", ret);