[120/192] kernel/events/uprobes: use vma_lookup() in find_active_uprobe()

Commit Message

Andrew Morton June 29, 2021, 2:39 a.m. UTC

From: Liam Howlett <[e-mail]>
Subject: kernel/events/uprobes: use vma_lookup() in find_active_uprobe()

Use vma_lookup() to find the VMA at a specific address.  As vma_lookup()
will return NULL if the address is not within any VMA, the start address
no longer needs to be validated.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Liam R. Howlett <[e-mail]>
Reviewed-by: Laurent Dufour <[e-mail]>
Acked-by: David Hildenbrand <[e-mail]>
Acked-by: Davidlohr Bueso <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 kernel/events/uprobes.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Patch

--- a/kernel/events/uprobes.c~kernel-events-uprobes-use-vma_lookup-in-find_active_uprobe
+++ a/kernel/events/uprobes.c
@@ -2046,8 +2046,8 @@  static struct uprobe *find_active_uprobe
 	struct vm_area_struct *vma;
 
 	mmap_read_lock(mm);
-	vma = find_vma(mm, bp_vaddr);
-	if (vma && vma->vm_start <= bp_vaddr) {
+	vma = vma_lookup(mm, bp_vaddr);
+	if (vma) {
 		if (valid_vma(vma, false)) {
 			struct inode *inode = file_inode(vma->vm_file);
 			loff_t offset = vaddr_to_offset(vma, bp_vaddr);