commit 0e1412e08eae0e5e8c1bb91da1d86c7bca1b2d72
author Florian Mayer <fmayer@google.com> Wed Mar 06 16:42:45 2024 -0800
committer Florian Mayer <fmayer@google.com> Wed Mar 06 16:46:45 2024 -0800
tree ee31eb64e0f3e17bd297cccce5d9de9cc05f4c6d
parent 2c0e9a58ead53aff66f0978c51142d8331ffffb0

Make memtag_handle_longjmp precise

We would get the SP inside of memtag_handle_longjmp, which could prevent
us from detecting the case where a longjmp is going into a function that
had already returned. This changes makes the behaviour more predictable.

Change-Id: I75bf931c8f4129a2f38001156b7bbe0b54a726ee

libc/arch-arm64/bionic/setjmp.S

diff --git a/libc/arch-arm64/bionic/setjmp.S b/libc/arch-arm64/bionic/setjmp.S
index 178c4c8..c408998 100644
--- a/libc/arch-arm64/bionic/setjmp.S
+++ b/libc/arch-arm64/bionic/setjmp.S
@@ -201,6 +201,7 @@
   bic x2, x2, #1
   ldr x0, [x0, #(_JB_X30_SP  * 8 + 8)]
   eor x0, x0, x2
+  add x1, sp, #16
   bl memtag_handle_longjmp
 
   mov x1, x19 // Restore 'value'.