aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorGordon Tetlow <gordon@FreeBSD.org>2020-09-02 16:21:27 +0000
committerGordon Tetlow <gordon@FreeBSD.org>2020-09-02 16:21:27 +0000
commitac5a6eb691d7a5f809ad93588861bd7aa1751d80 (patch)
treee1d9d41e9479f3931f6e9d48e3d117db179308e1
parent1bd042c01e887eaf6b77cd2cf32327cabd5abace (diff)
downloadsrc-ac5a6eb691d7a5f809ad93588861bd7aa1751d80.tar.gz
src-ac5a6eb691d7a5f809ad93588861bd7aa1751d80.zip
Fix FreeBSD Linux ABI kernel panic.
Approved by: so Security: FreeBSD-EN-20:17.linuxthread
Notes
Notes: svn path=/releng/11.4/; revision=365253
-rw-r--r--sys/compat/linux/linux_emul.c40
1 files changed, 26 insertions, 14 deletions
diff --git a/sys/compat/linux/linux_emul.c b/sys/compat/linux/linux_emul.c
index 9316beda11ec..75786862da3a 100644
--- a/sys/compat/linux/linux_emul.c
+++ b/sys/compat/linux/linux_emul.c
@@ -261,22 +261,13 @@ linux_common_execve(struct thread *td, struct image_args *eargs)
void
linux_proc_exec(void *arg __unused, struct proc *p, struct image_params *imgp)
{
- struct thread *td = curthread;
+ struct thread *td;
struct thread *othertd;
#if defined(__amd64__)
struct linux_pemuldata *pem;
#endif
- /*
- * In a case of execing from Linux binary properly detach
- * other threads from the user space.
- */
- if (__predict_false(SV_PROC_ABI(p) == SV_ABI_LINUX)) {
- FOREACH_THREAD_IN_PROC(p, othertd) {
- if (td != othertd)
- (p->p_sysent->sv_thread_detach)(othertd);
- }
- }
+ td = curthread;
/*
* In a case of execing to Linux binary we create Linux
@@ -284,11 +275,32 @@ linux_proc_exec(void *arg __unused, struct proc *p, struct image_params *imgp)
*/
if (__predict_false((imgp->sysent->sv_flags & SV_ABI_MASK) ==
SV_ABI_LINUX)) {
-
- if (SV_PROC_ABI(p) == SV_ABI_LINUX)
+ if (SV_PROC_ABI(p) == SV_ABI_LINUX) {
+ /*
+ * Process already was under Linuxolator
+ * before exec. Update emuldata to reflect
+ * single-threaded cleaned state after exec.
+ */
linux_proc_init(td, NULL, 0);
- else
+ } else {
+ /*
+ * We are switching the process to Linux emulator.
+ */
linux_proc_init(td, td, 0);
+
+ /*
+ * Create a transient td_emuldata for all suspended
+ * threads, so that p->p_sysent->sv_thread_detach() ==
+ * linux_thread_detach() can find expected but unused
+ * emuldata.
+ */
+ FOREACH_THREAD_IN_PROC(td->td_proc, othertd) {
+ if (othertd != td) {
+ linux_proc_init(td, othertd,
+ LINUX_CLONE_THREAD);
+ }
+ }
+ }
#if defined(__amd64__)
/*
* An IA32 executable which has executable stack will have the