From: Rich Felker <dalias@aerifal.cx>
Date: Sun, 11 Nov 2012 18:56:37 +0000 (-0500)
Subject: fix clobber of edx in i386 vsyscall asm
X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=commitdiff_plain;h=e9b885ee550e8a3eabc9d11c469baf1cfaf64f55

fix clobber of edx in i386 vsyscall asm

this function does not obey the normal calling convention; like a
syscall instruction, it's expected not to clobber any registers except
the return value. clobbering edx could break callers that were reusing
the value cached in edx after the syscall returns.
---

diff --git a/src/internal/i386/syscall.s b/src/internal/i386/syscall.s
index 291168c3..2914acee 100644
--- a/src/internal/i386/syscall.s
+++ b/src/internal/i386/syscall.s
@@ -16,7 +16,8 @@ __vsyscall:
 	mov 12(%esp),%edi
 	push %eax
 	call 1f
-2:	pop %ebx
+2:	mov %ebx,%edx
+	pop %ebx
 	pop %ebx
 	pop %edi
 	ret