This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments.
find_active_uprobe() uses user pointers (obtained via instruction_pointer(regs)) for vma lookups, which can only by done with untagged pointers.
Untag user pointers in this function.
Signed-off-by: Andrey Konovalov andreyknvl@google.com --- kernel/events/uprobes.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index c5cde87329c7..d3a2716a813a 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1992,6 +1992,8 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp) struct uprobe *uprobe = NULL; struct vm_area_struct *vma;
+ bp_vaddr = untagged_addr(bp_vaddr); + down_read(&mm->mmap_sem); vma = find_vma(mm, bp_vaddr); if (vma && vma->vm_start <= bp_vaddr) {