aboutsummaryrefslogtreecommitdiff
path: root/arch/um/include
diff options
context:
space:
mode:
authorJohannes Berg2020-12-05 21:50:18 +0100
committerRichard Weinberger2020-12-13 22:38:06 +0100
commitef4459a6da0955b533ebfc97a7d756ac090f50c9 (patch)
tree5c1153080467c99b2f60942757f644d38338319b /arch/um/include
parent963285b0b47a1b8e1dfa5481717855a7057ccec6 (diff)
um: allocate a guard page to helper threads
We've been running into stack overflows in helper threads corrupting memory (e.g. because somebody put printf() or os_info() there), so to avoid those causing hard-to-debug issues later on, allocate a guard page for helper thread stacks and mark it read-only. Unfortunately, the crash dump at that point is useless as the stack tracer will try to backtrace the *kernel* thread, not the helper thread, but at least we don't survive to a random issue caused by corruption. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/include')
-rw-r--r--arch/um/include/shared/kern_util.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/um/include/shared/kern_util.h b/arch/um/include/shared/kern_util.h
index 2888ec812f6e..d8c279e3312f 100644
--- a/arch/um/include/shared/kern_util.h
+++ b/arch/um/include/shared/kern_util.h
@@ -19,7 +19,7 @@ extern int kmalloc_ok;
#define UML_ROUND_UP(addr) \
((((unsigned long) addr) + PAGE_SIZE - 1) & PAGE_MASK)
-extern unsigned long alloc_stack(int order, int atomic);
+extern unsigned long alloc_stack(int atomic);
extern void free_stack(unsigned long stack, int order);
struct pt_regs;