diff options
| author | Helge Deller <deller@gmx.de> | 2021-10-05 00:05:43 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-26 11:40:29 +0100 |
| commit | 020acc6e866c108e5a326e0f54a94ec62f2194b5 (patch) | |
| tree | c45281186e27d12934b5beec392eb49e9bf80a42 | |
| parent | 9e58837beefbafecb999ed31a30307e20abf93fb (diff) | |
task_stack: Fix end_of_stack() for architectures with upwards-growing stack
[ Upstream commit 9cc2fa4f4a92ccc6760d764e7341be46ee8aaaa1 ]
The function end_of_stack() returns a pointer to the last entry of a
stack. For architectures like parisc where the stack grows upwards
return the pointer to the highest address in the stack.
Without this change I faced a crash on parisc, because the stackleak
functionality wrote STACKLEAK_POISON to the lowest address and thus
overwrote the first 4 bytes of the task_struct which included the
TIF_FLAGS.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/linux/sched/task_stack.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/sched/task_stack.h b/include/linux/sched/task_stack.h index cb4828aaa34f..3461beb89b04 100644 --- a/include/linux/sched/task_stack.h +++ b/include/linux/sched/task_stack.h @@ -25,7 +25,11 @@ static inline void *task_stack_page(const struct task_struct *task) static inline unsigned long *end_of_stack(const struct task_struct *task) { +#ifdef CONFIG_STACK_GROWSUP + return (unsigned long *)((unsigned long)task->stack + THREAD_SIZE) - 1; +#else return task->stack; +#endif } #elif !defined(__HAVE_THREAD_FUNCTIONS) |