6.16-stable review patch. If anyone has any objections, please let me know.
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From: Kees Cook kees@kernel.org
[ Upstream commit 32e42ab9fc88a884435c27527a433f61c4d2b61b ]
Add missing const qualifier to the non-CONFIG_THREAD_INFO_IN_TASK version of end_of_stack() to match the CONFIG_THREAD_INFO_IN_TASK version. Fixes a warning with CONFIG_KSTACK_ERASE=y on archs that don't select THREAD_INFO_IN_TASK (such as LoongArch):
error: passing 'const struct task_struct *' to parameter of type 'struct task_struct *' discards qualifiers
The stackleak_task_low_bound() function correctly uses a const task parameter, but the legacy end_of_stack() prototype didn't like that.
Build tested on loongarch (with CONFIG_KSTACK_ERASE=y) and m68k (with CONFIG_DEBUG_STACK_USAGE=y).
Fixes: a45728fd4120 ("LoongArch: Enable HAVE_ARCH_STACKLEAK") Reported-by: Nathan Chancellor nathan@kernel.org Closes: https://lore.kernel.org/all/20250726004313.GA3650901@ax162 Cc: Youling Tang tangyouling@kylinos.cn Cc: Huacai Chen chenhuacai@loongson.cn Tested-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Kees Cook kees@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/sched/task_stack.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/sched/task_stack.h b/include/linux/sched/task_stack.h index 85c5a6392e02..1fab7e9043a3 100644 --- a/include/linux/sched/task_stack.h +++ b/include/linux/sched/task_stack.h @@ -53,7 +53,7 @@ static inline void setup_thread_stack(struct task_struct *p, struct task_struct * When the stack grows up, this is the highest address. * Beyond that position, we corrupt data on the next page. */ -static inline unsigned long *end_of_stack(struct task_struct *p) +static inline unsigned long *end_of_stack(const struct task_struct *p) { #ifdef CONFIG_STACK_GROWSUP return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;