From: Rick Edgecombe <rick.p.edgecombe@intel.com>
To: 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>,
Borislav Petkov <bp@alien8.de>, Nadav Amit <nadav.amit@gmail.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Peter Zijlstra <peterz@infradead.org>,
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,
Nadav Amit <namit@vmware.com>,
Rick Edgecombe <rick.p.edgecombe@intel.com>
Subject: [PATCH 17/17] module: Prevent module removal racing with text_poke()
Date: Wed, 16 Jan 2019 16:32:59 -0800 [thread overview]
Message-ID: <20190117003259.23141-18-rick.p.edgecombe@intel.com> (raw)
In-Reply-To: <20190117003259.23141-1-rick.p.edgecombe@intel.com>
From: Nadav Amit <namit@vmware.com>
It seems dangerous to allow code modifications to take place
concurrently with module unloading. So take the text_mutex while the
memory of the module is freed.
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
kernel/module.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/kernel/module.c b/kernel/module.c
index 1af5c8e19086..90cfc4988d98 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -64,6 +64,7 @@
#include <linux/bsearch.h>
#include <linux/dynamic_debug.h>
#include <linux/audit.h>
+#include <linux/memory.h>
#include <uapi/linux/module.h>
#include "module-internal.h"
@@ -2157,6 +2158,9 @@ static void free_module(struct module *mod)
synchronize_rcu();
mutex_unlock(&module_mutex);
+ /* Protect against patching of the module while it is being removed */
+ mutex_lock(&text_mutex);
+
/* This may be empty, but that's OK */
module_arch_freeing_init(mod);
module_memfree(mod->init_layout.base);
@@ -2168,6 +2172,7 @@ static void free_module(struct module *mod)
/* Finally, free the core (containing the module structure) */
module_memfree(mod->core_layout.base);
+ mutex_unlock(&text_mutex);
}
void *__symbol_get(const char *symbol)
--
2.17.1
next prev parent reply other threads:[~2019-01-17 0:32 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-17 0:32 [PATCH 00/17] Merge text_poke fixes and executable lockdowns Rick Edgecombe
2019-01-17 0:32 ` [PATCH 01/17] Fix "x86/alternatives: Lockdep-enforce text_mutex in text_poke*()" Rick Edgecombe
2019-01-17 6:47 ` Masami Hiramatsu
2019-01-17 21:15 ` hpa
2019-01-17 22:39 ` Nadav Amit
2019-01-17 22:59 ` hpa
2019-01-17 23:14 ` Nadav Amit
2019-01-25 9:30 ` Borislav Petkov
2019-01-25 18:28 ` Nadav Amit
2019-01-17 0:32 ` [PATCH 02/17] x86/jump_label: Use text_poke_early() during early init Rick Edgecombe
2019-01-17 0:32 ` [PATCH 03/17] x86/mm: temporary mm struct Rick Edgecombe
2019-01-17 0:32 ` [PATCH 04/17] fork: provide a function for copying init_mm Rick Edgecombe
2019-01-17 0:32 ` [PATCH 05/17] x86/alternative: initializing temporary mm for patching Rick Edgecombe
2019-01-17 0:32 ` [PATCH 06/17] x86/alternative: use temporary mm for text poking Rick Edgecombe
2019-01-17 20:27 ` Andy Lutomirski
2019-01-17 20:47 ` Andy Lutomirski
2019-01-17 21:43 ` Nadav Amit
2019-01-17 22:29 ` Nadav Amit
2019-01-17 22:31 ` hpa
2019-01-17 0:32 ` [PATCH 07/17] x86/kgdb: avoid redundant comparison of patched code Rick Edgecombe
2019-01-17 0:32 ` [PATCH 08/17] x86/ftrace: set trampoline pages as executable Rick Edgecombe
2019-02-06 16:22 ` Steven Rostedt
2019-02-06 17:33 ` Nadav Amit
2019-02-06 17:41 ` Steven Rostedt
2019-01-17 0:32 ` [PATCH 09/17] x86/kprobes: Instruction pages initialization enhancements Rick Edgecombe
2019-01-17 6:51 ` Masami Hiramatsu
2019-01-17 0:32 ` [PATCH 10/17] x86: avoid W^X being broken during modules loading Rick Edgecombe
2019-01-17 0:32 ` [PATCH 11/17] x86/jump-label: remove support for custom poker Rick Edgecombe
2019-01-17 0:32 ` [PATCH 12/17] x86/alternative: Remove the return value of text_poke_*() Rick Edgecombe
2019-01-17 0:32 ` [PATCH 13/17] Add set_alias_ function and x86 implementation Rick Edgecombe
2019-01-17 0:32 ` [PATCH 14/17] mm: Make hibernate handle unmapped pages Rick Edgecombe
2019-01-17 9:39 ` Pavel Machek
2019-01-17 22:16 ` Edgecombe, Rick P
2019-01-17 23:41 ` Pavel Machek
2019-01-17 23:48 ` Edgecombe, Rick P
2019-01-18 8:16 ` Pavel Machek
2019-01-17 0:32 ` [PATCH 15/17] vmalloc: New flags for safe vfree on special perms Rick Edgecombe
2019-01-17 0:32 ` [PATCH 16/17] Plug in new special vfree flag Rick Edgecombe
2019-02-06 16:23 ` Steven Rostedt
2019-02-07 17:33 ` Edgecombe, Rick P
2019-02-07 17:49 ` Steven Rostedt
2019-02-07 18:20 ` Edgecombe, Rick P
2019-01-17 0:32 ` Rick Edgecombe [this message]
2019-01-17 7:54 ` [PATCH 17/17] module: Prevent module removal racing with text_poke() Masami Hiramatsu
2019-01-17 18:07 ` Nadav Amit
2019-01-17 23:44 ` H. Peter Anvin
2019-01-18 8:23 ` Masami Hiramatsu
2019-01-17 23:58 ` H. Peter Anvin
2019-01-18 1:15 ` Nadav Amit
2019-01-18 13:32 ` Masami Hiramatsu
2019-01-17 13:21 ` [PATCH 00/17] Merge text_poke fixes and executable lockdowns Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190117003259.23141-18-rick.p.edgecombe@intel.com \
--to=rick.p.edgecombe@intel.com \
--cc=akpm@linux-foundation.org \
--cc=ard.biesheuvel@linaro.org \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=deneen.t.dock@intel.com \
--cc=hpa@zytor.com \
--cc=kernel-hardening@lists.openwall.com \
--cc=kristen@linux.intel.com \
--cc=linux-integrity@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-security-module@vger.kernel.org \
--cc=linux_dti@icloud.com \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=nadav.amit@gmail.com \
--cc=namit@vmware.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=will.deacon@arm.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).