[PATCHv5 04/13] uprobes/x86: Allow to copy uprobe trampolines on fork
From: Jiri Olsa <jolsa@kernel.org>
Date: 2026-07-01 11:14:26
Also in:
bpf
Subsystem:
the rest, uprobes, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
When we do fork or clone without CLONE_VM the new process won't
have uprobe trampoline vma objects and at the same time it will
have optimized code calling that trampoline and crash.
Fixing this by allowing vma uprobe trampoline objects to be copied
on fork to the new process.
Fixes: ba2bfc97b462 ("uprobes/x86: Add support to optimize uprobes")
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
arch/x86/kernel/uprobes.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 5730d41eb5f2..af5af7d67999 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c@@ -701,7 +701,7 @@ static struct vm_area_struct *get_uprobe_trampoline(struct mm_struct *mm, unsign *new_mapping = true; return _install_special_mapping(mm, vaddr, PAGE_SIZE, - VM_READ|VM_EXEC|VM_MAYEXEC|VM_MAYREAD|VM_DONTCOPY|VM_IO, + VM_READ|VM_EXEC|VM_MAYEXEC|VM_MAYREAD|VM_IO, &tramp_mapping); }
--
2.54.0