git: 83f3bc609090 - stable/12 - amd64: clear debug registers on execing 32bit Linux binary

[Konstantin Belousov]

The branch stable/12 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=83f3bc609090aedb9b276e4f2b43e570857fd153

commit 83f3bc609090aedb9b276e4f2b43e570857fd153
Author:     Konstantin Belousov <kib at FreeBSD.org>
AuthorDate: 2021-04-09 23:25:06 +0000
Commit:     Konstantin Belousov <kib at FreeBSD.org>
CommitDate: 2021-05-01 00:38:29 +0000

    amd64: clear debug registers on execing 32bit Linux binary
    
    (cherry picked from commit 94172affa43af15fe3b50293a96c292eca30c386)
---
 sys/amd64/linux32/linux32_sysvec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/amd64/linux32/linux32_sysvec.c b/sys/amd64/linux32/linux32_sysvec.c
index 315dcc7ca629..1686891861c3 100644
--- a/sys/amd64/linux32/linux32_sysvec.c
+++ b/sys/amd64/linux32/linux32_sysvec.c
@@ -710,6 +710,8 @@ linux_exec_setregs(struct thread *td, struct image_params *imgp, u_long stack)
 	regs->tf_cs = _ucode32sel;
 	regs->tf_rbx = imgp->ps_strings;
 
+	x86_clear_dbregs(pcb);
+
 	fpstate_drop(td);
 
 	/* Do full restore on return so that we can change to a different %cs */