From: Nadav Amit <namit@vmware.com>
To: Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@alien8.de>, Andy Lutomirski <luto@kernel.org>,
Ingo Molnar <mingo@redhat.com>
Cc: <linux-kernel@vger.kernel.org>, <x86@kernel.org>, <hpa@zytor.com>,
Thomas Gleixner <tglx@linutronix.de>,
Nadav Amit <nadav.amit@gmail.com>,
Dave Hansen <dave.hansen@linux.intel.com>, <linux_dti@icloud.com>,
<linux-integrity@vger.kernel.org>,
<linux-security-module@vger.kernel.org>,
<akpm@linux-foundation.org>,
<kernel-hardening@lists.openwall.com>, <linux-mm@kvack.org>,
<will.deacon@arm.com>, <ard.biesheuvel@linaro.org>,
<kristen@linux.intel.com>, <deneen.t.dock@intel.com>,
Rick Edgecombe <rick.p.edgecombe@intel.com>,
Nadav Amit <namit@vmware.com>, Kees Cook <keescook@chromium.org>,
Dave Hansen <dave.hansen@intel.com>
Subject: [PATCH v5 05/23] fork: Provide a function for copying init_mm
Date: Thu, 25 Apr 2019 17:11:25 -0700 [thread overview]
Message-ID: <20190426001143.4983-6-namit@vmware.com> (raw)
In-Reply-To: <20190426001143.4983-1-namit@vmware.com>
Provide a function for copying init_mm. This function will be later used
for setting a temporary mm.
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
include/linux/sched/task.h | 1 +
kernel/fork.c | 24 ++++++++++++++++++------
2 files changed, 19 insertions(+), 6 deletions(-)
diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h
index 2e97a2227045..f1227f2c38a4 100644
--- a/include/linux/sched/task.h
+++ b/include/linux/sched/task.h
@@ -76,6 +76,7 @@ extern void exit_itimers(struct signal_struct *);
extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
struct task_struct *fork_idle(int);
+struct mm_struct *copy_init_mm(void);
extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
extern long kernel_wait4(pid_t, int __user *, int, struct rusage *);
diff --git a/kernel/fork.c b/kernel/fork.c
index 9dcd18aa210b..099cca8f701c 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1298,13 +1298,20 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
complete_vfork_done(tsk);
}
-/*
- * Allocate a new mm structure and copy contents from the
- * mm structure of the passed in task structure.
+/**
+ * dup_mm() - duplicates an existing mm structure
+ * @tsk: the task_struct with which the new mm will be associated.
+ * @oldmm: the mm to duplicate.
+ *
+ * Allocates a new mm structure and duplicates the provided @oldmm structure
+ * content into it.
+ *
+ * Return: the duplicated mm or NULL on failure.
*/
-static struct mm_struct *dup_mm(struct task_struct *tsk)
+static struct mm_struct *dup_mm(struct task_struct *tsk,
+ struct mm_struct *oldmm)
{
- struct mm_struct *mm, *oldmm = current->mm;
+ struct mm_struct *mm;
int err;
mm = allocate_mm();
@@ -1371,7 +1378,7 @@ static int copy_mm(unsigned long clone_flags, struct task_struct *tsk)
}
retval = -ENOMEM;
- mm = dup_mm(tsk);
+ mm = dup_mm(tsk, current->mm);
if (!mm)
goto fail_nomem;
@@ -2186,6 +2193,11 @@ struct task_struct *fork_idle(int cpu)
return task;
}
+struct mm_struct *copy_init_mm(void)
+{
+ return dup_mm(NULL, &init_mm);
+}
+
/*
* Ok, this is the main fork-routine.
*
--
2.17.1
next prev parent reply other threads:[~2019-04-26 7:33 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-26 0:11 [PATCH v5 00/23] x86: text_poke() fixes and executable lockdowns Nadav Amit
2019-04-26 0:11 ` [PATCH v5 01/23] Fix "x86/alternatives: Lockdep-enforce text_mutex in text_poke*()" Nadav Amit
2019-04-30 11:13 ` [tip:x86/mm] x86/alternatives: Add text_poke_kgdb() to not assert the lock when debugging tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 02/23] x86/jump_label: Use text_poke_early() during early init Nadav Amit
2019-04-30 11:15 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 03/23] x86/mm: Introduce temporary mm structs Nadav Amit
2019-04-30 11:16 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2019-04-26 0:11 ` [PATCH v5 04/23] x86/mm: Save debug registers when loading a temporary mm Nadav Amit
2019-04-30 11:17 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 0:11 ` Nadav Amit [this message]
2019-04-30 11:18 ` [tip:x86/mm] fork: Provide a function for copying init_mm tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 06/23] x86/alternative: Initialize temporary mm for patching Nadav Amit
2019-04-26 0:11 ` [PATCH v5 07/23] x86/alternative: Use temporary mm for text poking Nadav Amit
2019-04-30 11:20 ` [tip:x86/mm] x86/alternatives: " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 08/23] x86/kgdb: Avoid redundant comparison of patched code Nadav Amit
2019-04-30 11:20 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 09/23] x86/ftrace: Set trampoline pages as executable Nadav Amit
2019-04-30 11:21 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 10/23] x86/kprobes: Set instruction page " Nadav Amit
2019-04-30 11:22 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 11/23] x86/module: Avoid breaking W^X while loading modules Nadav Amit
2019-04-30 11:22 ` [tip:x86/mm] x86/modules: " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 12/23] x86/jump-label: Remove support for custom poker Nadav Amit
2019-04-30 11:23 ` [tip:x86/mm] x86/jump-label: Remove support for custom text poker tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 13/23] x86/alternative: Remove the return value of text_poke_*() Nadav Amit
2019-04-30 11:24 ` [tip:x86/mm] x86/alternatives: " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 14/23] x86/mm/cpa: Add set_direct_map_ functions Nadav Amit
2019-04-26 16:40 ` Linus Torvalds
2019-04-26 16:43 ` Nadav Amit
2019-04-30 11:24 ` [tip:x86/mm] x86/mm/cpa: Add set_direct_map_*() functions tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 15/23] mm: Make hibernate handle unmapped pages Nadav Amit
2019-04-30 11:25 ` [tip:x86/mm] mm/hibernation: Make hibernation " tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 16/23] vmalloc: Add flag for free of special permsissions Nadav Amit
2019-04-30 11:26 ` [tip:x86/mm] mm/vmalloc: Add flag for freeing " tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 17/23] modules: Use vmalloc special flag Nadav Amit
2019-04-30 11:26 ` [tip:x86/mm] " tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 18/23] bpf: " Nadav Amit
2019-04-30 11:27 ` [tip:x86/mm] " tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 19/23] x86/ftrace: " Nadav Amit
2019-04-30 11:28 ` [tip:x86/mm] " tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 20/23] x86/kprobes: " Nadav Amit
2019-04-30 11:28 ` [tip:x86/mm] " tip-bot for Rick Edgecombe
2019-04-26 0:11 ` [PATCH v5 21/23] x86/alternative: Comment about module removal races Nadav Amit
2019-04-30 11:29 ` [tip:x86/mm] x86/alternatives: Add comment " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 22/23] mm/tlb: Provide default nmi_uaccess_okay() Nadav Amit
2019-04-30 11:14 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 0:11 ` [PATCH v5 23/23] bpf: Fail bpf_probe_write_user() while mm is switched Nadav Amit
2019-04-30 11:15 ` [tip:x86/mm] " tip-bot for Nadav Amit
2019-04-26 12:36 ` [PATCH v5 00/23] x86: text_poke() fixes and executable lockdowns Peter Zijlstra
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