From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:34364 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751282AbdHDT4D (ORCPT ); Fri, 4 Aug 2017 15:56:03 -0400 Subject: Patch "pstore: Correctly initialize spinlock and flags" has been added to the 3.18-stable tree To: keescook@chromium.org, briannorris@chromium.org, gregkh@linuxfoundation.org Cc: , From: Date: Fri, 04 Aug 2017 12:56:00 -0700 Message-ID: <150187656018919@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled pstore: Correctly initialize spinlock and flags to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pstore-correctly-initialize-spinlock-and-flags.patch and it can be found in the queue-3.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 76d5692a58031696e282384cbd893832bc92bd76 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 9 Feb 2017 15:43:44 -0800 Subject: pstore: Correctly initialize spinlock and flags From: Kees Cook commit 76d5692a58031696e282384cbd893832bc92bd76 upstream. The ram backend wasn't always initializing its spinlock correctly. Since it was coming from kzalloc memory, though, it was harmless on architectures that initialize unlocked spinlocks to 0 (at least x86 and ARM). This also fixes a possibly ignored flag setting too. When running under CONFIG_DEBUG_SPINLOCK, the following Oops was visible: [ 0.760836] persistent_ram: found existing buffer, size 29988, start 29988 [ 0.765112] persistent_ram: found existing buffer, size 30105, start 30105 [ 0.769435] persistent_ram: found existing buffer, size 118542, start 118542 [ 0.785960] persistent_ram: found existing buffer, size 0, start 0 [ 0.786098] persistent_ram: found existing buffer, size 0, start 0 [ 0.786131] pstore: using zlib compression [ 0.790716] BUG: spinlock bad magic on CPU#0, swapper/0/1 [ 0.790729] lock: 0xffffffc0d1ca9bb0, .magic: 00000000, .owner: /-1, .owner_cpu: 0 [ 0.790742] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.10.0-rc2+ #913 [ 0.790747] Hardware name: Google Kevin (DT) [ 0.790750] Call trace: [ 0.790768] [] dump_backtrace+0x0/0x2bc [ 0.790780] [] show_stack+0x20/0x28 [ 0.790794] [] dump_stack+0xa4/0xcc [ 0.790809] [] spin_dump+0xe0/0xf0 [ 0.790821] [] spin_bug+0x30/0x3c [ 0.790834] [] do_raw_spin_lock+0x50/0x1b8 [ 0.790846] [] _raw_spin_lock_irqsave+0x54/0x6c [ 0.790862] [] buffer_size_add+0x48/0xcc [ 0.790875] [] persistent_ram_write+0x60/0x11c [ 0.790888] [] ramoops_pstore_write_buf+0xd4/0x2a4 [ 0.790900] [] pstore_console_write+0xf0/0x134 [ 0.790912] [] console_unlock+0x48c/0x5e8 [ 0.790923] [] register_console+0x3b0/0x4d4 [ 0.790935] [] pstore_register+0x1a8/0x234 [ 0.790947] [] ramoops_probe+0x6b8/0x7d4 [ 0.790961] [] platform_drv_probe+0x7c/0xd0 [ 0.790972] [] driver_probe_device+0x1b4/0x3bc [ 0.790982] [] __device_attach_driver+0xc8/0xf4 [ 0.790996] [] bus_for_each_drv+0xb4/0xe4 [ 0.791006] [] __device_attach+0xd0/0x158 [ 0.791016] [] device_initial_probe+0x24/0x30 [ 0.791026] [] bus_probe_device+0x50/0xe4 [ 0.791038] [] device_add+0x3a4/0x76c [ 0.791051] [] of_device_add+0x74/0x84 [ 0.791062] [] of_platform_device_create_pdata+0xc0/0x100 [ 0.791073] [] of_platform_device_create+0x34/0x40 [ 0.791086] [] of_platform_default_populate_init+0x58/0x78 [ 0.791097] [] do_one_initcall+0x88/0x160 [ 0.791109] [] kernel_init_freeable+0x264/0x31c [ 0.791123] [] kernel_init+0x18/0x11c [ 0.791133] [] ret_from_fork+0x10/0x50 [ 0.793717] console [pstore-1] enabled [ 0.797845] pstore: Registered ramoops as persistent store backend [ 0.804647] ramoops: attached 0x100000@0xf7edc000, ecc: 0/0 Fixes: 663deb47880f ("pstore: Allow prz to control need for locking") Fixes: 109704492ef6 ("pstore: Make spinlock per zone instead of global") Reported-by: Brian Norris Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- fs/pstore/ram_core.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -463,8 +463,7 @@ static int persistent_ram_buffer_map(phy } static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, - struct persistent_ram_ecc_info *ecc_info, - unsigned long flags) + struct persistent_ram_ecc_info *ecc_info) { int ret; @@ -490,10 +489,9 @@ static int persistent_ram_post_init(stru prz->buffer->sig); } + /* Rewind missing or invalid memory area. */ prz->buffer->sig = sig; persistent_ram_zap(prz); - prz->buffer_lock = __RAW_SPIN_LOCK_UNLOCKED(buffer_lock); - prz->flags = flags; return 0; } @@ -529,11 +527,15 @@ struct persistent_ram_zone *persistent_r goto err; } + /* Initialize general buffer state. */ + prz->buffer_lock = __RAW_SPIN_LOCK_UNLOCKED(buffer_lock); + prz->flags = flags; + ret = persistent_ram_buffer_map(start, size, prz, memtype); if (ret) goto err; - ret = persistent_ram_post_init(prz, sig, ecc_info, flags); + ret = persistent_ram_post_init(prz, sig, ecc_info); if (ret) goto err; Patches currently in stable-queue which might be from keescook@chromium.org are queue-3.18/pstore-make-spinlock-per-zone-instead-of-global.patch queue-3.18/pstore-correctly-initialize-spinlock-and-flags.patch queue-3.18/pstore-allow-prz-to-control-need-for-locking.patch queue-3.18/isdn-i4l-fix-buffer-overflow.patch queue-3.18/pstore-use-dynamic-spinlock-initializer.patch