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path: root/fs/pstore/ram.c
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2024-06-19pstore/ramoops: Add ramoops.mem_name= command line optionSteven Rostedt (Google)
Add a method to find a region specified by reserve_mem=nn:align:name for ramoops. Adding a kernel command line parameter: reserve_mem=12M:4096:oops ramoops.mem_name=oops Will use the size and location defined by the memmap parameter where it finds the memory and labels it "oops". The "oops" in the ramoops option is used to search for it. This allows for arbitrary RAM to be used for ramoops if it is known that the memory is not cleared on kernel crashes or soft reboots. Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20240613155527.591647061@goodmis.org Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
2024-02-22pstore/ram: Register to module device tableNícolas F. R. A. Prado
Register the compatible for this module on the module device table so it can be automatically loaded when a matching DT node is present, allowing logging of panics and oopses without any intervention. Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Link: https://lore.kernel.org/r/20240110210600.787703-2-nfraprado@collabora.com Signed-off-by: Kees Cook <keescook@chromium.org>
2023-12-08pstore/ram: Fix crash when setting number of cpus to an odd numberWeichen Chen
When the number of cpu cores is adjusted to 7 or other odd numbers, the zone size will become an odd number. The address of the zone will become: addr of zone0 = BASE addr of zone1 = BASE + zone_size addr of zone2 = BASE + zone_size*2 ... The address of zone1/3/5/7 will be mapped to non-alignment va. Eventually crashes will occur when accessing these va. So, use ALIGN_DOWN() to make sure the zone size is even to avoid this bug. Signed-off-by: Weichen Chen <weichen.chen@mediatek.com> Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> Tested-by: "Guilherme G. Piccoli" <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20230224023632.6840-1-weichen.chen@mediatek.com Signed-off-by: Kees Cook <keescook@chromium.org>
2023-08-17pstore: Support record sizes larger than kmalloc() limitYuxiao Zhang
Currently pstore record buffers are allocated using kmalloc() which has a maximum size based on page size. If a large "pmsg-size" module parameter is specified, pmsg will fail to copy the contents since memdup_user() is limited to kmalloc() allocation sizes. Since we don't need physically contiguous memory for any of the pstore record buffers, use kvzalloc() to avoid such limitations in the core of pstore and in the ram backend, and explicitly read from userspace using vmemdup_user(). This also means that any other backends that want to (or do already) support larger record sizes will Just Work now. Signed-off-by: Yuxiao Zhang <yuxiaozhang@google.com> Link: https://lore.kernel.org/r/20230627202540.881909-2-yuxiaozhang@google.com Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2023-05-10pstore/ram: Convert to platform remove callback returning voidUwe Kleine-König
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is (mostly) ignored and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new() which already returns void. Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230401120000.2487153-1-u.kleine-koenig@pengutronix.de
2022-12-23pstore: Properly assign mem_type propertyLuca Stefani
If mem-type is specified in the device tree it would end up overriding the record_size field instead of populating mem_type. As record_size is currently parsed after the improper assignment with default size 0 it continued to work as expected regardless of the value found in the device tree. Simply changing the target field of the struct is enough to get mem-type working as expected. Fixes: 9d843e8fafc7 ("pstore: Add mem_type property DT parsing support") Cc: stable@vger.kernel.org Signed-off-by: Luca Stefani <luca@osomprivacy.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221222131049.286288-1-luca@osomprivacy.com
2022-12-02pstore/ram: Fix error return code in ramoops_probe()Wang Yufen
In the if (dev_of_node(dev) && !pdata) path, the "err" may be assigned a value of 0, so the error return code -EINVAL may be incorrectly set to 0. To fix set valid return code before calling to goto. Fixes: 35da60941e44 ("pstore/ram: add Device Tree bindings") Signed-off-by: Wang Yufen <wangyufen@huawei.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/1669969374-46582-1-git-send-email-wangyufen@huawei.com
2022-10-19pstore/ram: Set freed addresses to NULLKees Cook
For good measure, set all the freed addresses to NULL when managing przs. Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-and-tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20221011200112.731334-5-keescook@chromium.org
2022-10-17pstore/ram: Move internal definitions out of kernel-wide includeKees Cook
Most of the details of the ram backend are entirely internal to the backend itself. Leave only what is needed to instantiate a ram backend in the kernel-wide header. Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-and-tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20221011200112.731334-4-keescook@chromium.org
2022-10-17pstore/ram: Move pmsg init earlierKees Cook
Since the ftrace area can vary in size based on CPU count, move pmsg initialization earlier so it will have a stable location. Suggested-by: Paramjit Oberoi <pso@chromium.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20221011200112.731334-3-keescook@chromium.org
2022-10-17pstore/ram: Consolidate kfree() pathsKees Cook
There's no reason to keep separate kfree() paths: either all allocations succeeded, or not. Everything is torn down in the case of failure, so adjust the callers to reflect this. Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-and-tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20221011200112.731334-2-keescook@chromium.org
2021-03-31pstore: Add mem_type property DT parsing supportMukesh Ojha
There could be a scenario where we define some region in normal memory and use them store to logs which is later retrieved by bootloader during warm reset. In this scenario, we wanted to treat this memory as normal cacheable memory instead of default behaviour which is an overhead. Making it cacheable could improve performance. This commit gives control to change mem_type from Device tree, and also documents the value for normal memory. Signed-off-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/1616438537-13719-1-git-send-email-mojha@codeaurora.org
2020-05-30pstore/ram: Introduce max_reason and convert dump_oopsKees Cook
Now that pstore_register() can correctly pass max_reason to the kmesg dump facility, introduce a new "max_reason" module parameter and "max-reason" Device Tree field. The "dump_oops" module parameter and "dump-oops" Device Tree field are now considered deprecated, but are now automatically converted to their corresponding max_reason values when present, though the new max_reason setting has precedence. For struct ramoops_platform_data, the "dump_oops" member is entirely replaced by a new "max_reason" member, with the only existing user updated in place. Additionally remove the "reason" filter logic from ramoops_pstore_write(), as that is not specifically needed anymore, though technically this is a change in behavior for any ramoops users also setting the printk.always_kmsg_dump boot param, which will cause ramoops to behave as if max_reason was set to KMSG_DUMP_MAX. Co-developed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Link: https://lore.kernel.org/lkml/20200515184434.8470-6-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30pstore/ftrace: Provide ftrace log merging routineKees Cook
Move the ftrace log merging logic out of pstore/ram into pstore/ftrace so other backends can use it, like pstore/zone. Link: https://lore.kernel.org/lkml/20200510202436.63222-7-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30pstore/ram: Refactor ftrace buffer mergingKees Cook
This changes the ftrace record merging code to be agnostic of pstore/ram, as the first step to making it available as a generic routine for other backends to use, such as pstore/zone. Link: https://lore.kernel.org/lkml/20200510202436.63222-6-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30pstore/ram: Refactor DT size parsingKees Cook
Refactor device tree size parsing routines to be able to pass a non-zero default value for providing a configurable default for the coming "max_reason" field. Also rename the helpers, since we're not always parsing a size -- we're parsing a u32 and making sure it's not greater than INT_MAX. Link: https://lore.kernel.org/lkml/20200506211523.15077-4-keescook@chromium.org/ Link: https://lore.kernel.org/lkml/20200521205223.175957-1-tyhicks@linux.microsoft.com Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30pstore/ram: Adjust module param permissions to reflect realityKees Cook
A couple module parameters had 0600 permissions, but changing them would have no impact on ramoops, so switch these to 0400 to reflect reality. Link: https://lore.kernel.org/lkml/20200506211523.15077-7-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2020-02-25pstore/ram: remove unnecessary ramoops_unregister_dummy()chenqiwu
Remove unnecessary ramoops_unregister_dummy() if ramoops platform device register failed. Signed-off-by: chenqiwu <chenqiwu@xiaomi.com> Link: https://lore.kernel.org/r/1581068800-13817-2-git-send-email-qiwuchen55@gmail.com Signed-off-by: Kees Cook <keescook@chromium.org>
2020-01-08pstore/ram: Regularize prz label allocation lifetimeKees Cook
In my attempt to fix a memory leak, I introduced a double-free in the pstore error path. Instead of trying to manage the allocation lifetime between persistent_ram_new() and its callers, adjust the logic so persistent_ram_new() always takes a kstrdup() copy, and leaves the caller's allocation lifetime up to the caller. Therefore callers are _always_ responsible for freeing their label. Before, it only needed freeing when the prz itself failed to allocate, and not in any of the other prz failure cases, which callers would have no visibility into, which is the root design problem that lead to both the leak and now double-free bugs. Reported-by: Cengiz Can <cengiz@kernel.wtf> Link: https://lore.kernel.org/lkml/d4ec59002ede4aaf9928c7f7526da87c@kernel.wtf Fixes: 8df955a32a73 ("pstore/ram: Fix error-path memory leak in persistent_ram_new() callers") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2020-01-02pstore/ram: Write new dumps to start of recycled zonesAleksandr Yashkin
The ram_core.c routines treat przs as circular buffers. When writing a new crash dump, the old buffer needs to be cleared so that the new dump doesn't end up in the wrong place (i.e. at the end). The solution to this problem is to reset the circular buffer state before writing a new Oops dump. Signed-off-by: Aleksandr Yashkin <a.yashkin@inango-systems.com> Signed-off-by: Nikolay Merinov <n.merinov@inango-systems.com> Signed-off-by: Ariel Gilman <a.gilman@inango-systems.com> Link: https://lore.kernel.org/r/20191223133816.28155-1-n.merinov@inango-systems.com Fixes: 896fc1f0c4c6 ("pstore/ram: Switch to persistent_ram routines") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2020-01-02pstore/ram: Fix error-path memory leak in persistent_ram_new() callersKees Cook
For callers that allocated a label for persistent_ram_new(), if the call fails, they must clean up the allocation. Suggested-by: Navid Emamdoost <navid.emamdoost@gmail.com> Fixes: 1227daa43bce ("pstore/ram: Clarify resource reservation labels") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/lkml/20191211191353.14385-1-navid.emamdoost@gmail.com Signed-off-by: Kees Cook <keescook@chromium.org>
2019-08-30pstore: fs superblock limitsDeepa Dinamani
Leaving granularity at 1ns because it is dependent on the specific attached backing pstore module. ramoops has microsecond resolution. Fix the readback of ramoops fractional timestamp microseconds, which has incorrectly been reporting the value as nanoseconds. Fixes: 3f8f80f0cfeb ("pstore/ram: Read and write to the 'compressed' flag of pstore"). Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Jeff Layton <jlayton@kernel.org> Cc: anton@enomsg.org Cc: ccross@android.com Cc: keescook@chromium.org Cc: tony.luck@intel.com
2019-07-08pstore/ram: Improve backward compatibility with older ChromebooksDouglas Anderson
When you try to run an upstream kernel on an old ARM-based Chromebook you'll find that console-ramoops doesn't work. Old ARM-based Chromebooks, before <https://crrev.com/c/439792> ("ramoops: support upstream {console,pmsg,ftrace}-size properties") used to create a "ramoops" node at the top level that looked like: / { ramoops { compatible = "ramoops"; reg = <...>; record-size = <...>; dump-oops; }; }; ...and these Chromebooks assumed that the downstream kernel would make console_size / pmsg_size match the record size. The above ramoops node was added by the firmware so it's not easy to make any changes. Let's match the expected behavior, but only for those using the old backward-compatible way of working where ramoops is right under the root node. NOTE: if there are some out-of-tree devices that had ramoops at the top level, left everything but the record size as 0, and somehow doesn't want this behavior, we can try to add more conditions here. Signed-off-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-06-08Merge tag 'spdx-5.2-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull yet more SPDX updates from Greg KH: "Another round of SPDX header file fixes for 5.2-rc4 These are all more "GPL-2.0-or-later" or "GPL-2.0-only" tags being added, based on the text in the files. We are slowly chipping away at the 700+ different ways people tried to write the license text. All of these were reviewed on the spdx mailing list by a number of different people. We now have over 60% of the kernel files covered with SPDX tags: $ ./scripts/spdxcheck.py -v 2>&1 | grep Files Files checked: 64533 Files with SPDX: 40392 Files with errors: 0 I think the majority of the "easy" fixups are now done, it's now the start of the longer-tail of crazy variants to wade through" * tag 'spdx-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (159 commits) treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 450 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 449 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 448 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 446 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 445 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 444 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 443 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 442 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 440 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 438 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 437 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 436 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 435 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 434 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 433 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 432 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 431 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 430 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 429 ...
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 246 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.674189849@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31pstore/ram: Run without kernel crash dump regionKees Cook
The ram pstore backend has always had the crash dumper frontend enabled unconditionally. However, it was possible to effectively disable it by setting a record_size=0. All the machinery would run (storing dumps to the temporary crash buffer), but 0 bytes would ultimately get stored due to there being no przs allocated for dumps. Commit 89d328f637b9 ("pstore/ram: Correctly calculate usable PRZ bytes"), however, assumed that there would always be at least one allocated dprz for calculating the size of the temporary crash buffer. This was, of course, not the case when record_size=0, and would lead to a NULL deref trying to find the dprz buffer size: BUG: unable to handle kernel NULL pointer dereference at (null) ... IP: ramoops_probe+0x285/0x37e (fs/pstore/ram.c:808) cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size; Instead, we need to only enable the frontends based on the success of the prz initialization and only take the needed actions when those zones are available. (This also fixes a possible error in detecting if the ftrace frontend should be enabled.) Reported-and-tested-by: Yaro Slav <yaro330@gmail.com> Fixes: 89d328f637b9 ("pstore/ram: Correctly calculate usable PRZ bytes") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2019-02-12pstore/ram: Avoid needless alloc during header writeKees Cook
Since the header is a fixed small maximum size, just use a stack variable to avoid memory allocation in the write path. Signed-off-by: Kees Cook <keescook@chromium.org>
2019-02-12pstore/ram: Add kmsg hlen zero check to ramoops_pstore_write()Yue Hu
If zero-length header happened in ramoops_write_kmsg_hdr(), that means we will not be able to read back dmesg record later, since it will be treated as invalid header in ramoops_pstore_read(). So we should not execute the following code but return the error. Signed-off-by: Yue Hu <huyue2@yulong.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-02-12pstore/ram: Move initialization earlierYue Hu
Since only one single ramoops area allowed at a time, other probes (like device tree) are meaningless, as it will waste CPU resources. So let's check for being already initialized first. Signed-off-by: Yue Hu <huyue2@yulong.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-02-12pstore: Avoid writing records with zero sizeYue Hu
Sometimes pstore_console_write() will write records with zero size to persistent ram zone, which is unnecessary. It will only increase resource consumption. Also adjust ramoops_write_kmsg_hdr() to have same logic if memory allocation fails. Signed-off-by: Yue Hu <huyue2@yulong.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-21pstore/ram: Replace dummy_data heap memory with stack memoryYue Hu
In ramoops_register_dummy() dummy_data is allocated via kzalloc() then it will always occupy the heap space after register platform device via platform_device_register_data(), but it will not be used any more. So let's free it for system usage, replace it with stack memory is better due to small size. Signed-off-by: Yue Hu <huyue2@yulong.com> [kees: add required memset and adjust sizeof() argument] Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-20pstore/ram: Avoid allocation and leak of platform dataKees Cook
Yue Hu noticed that when parsing device tree the allocated platform data was never freed. Since it's not used beyond the function scope, this switches to using a stack variable instead. Reported-by: Yue Hu <huyue2@yulong.com> Fixes: 35da60941e44 ("pstore/ram: add Device Tree bindings") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-17pstore/ram: Fix console ramoops to show the previous boot logsSai Prakash Ranjan
commit b05c950698fe ("pstore/ram: Simplify ramoops_get_next_prz() arguments") changed update assignment in getting next persistent ram zone by adding a check for record type. But the check always returns true since the record type is assigned 0. And this breaks console ramoops by showing current console log instead of previous log on warm reset and hard reset (actually hard reset should not be showing any logs). Fix this by having persistent ram zone type check instead of record type check. Tested this on SDM845 MTP and dragonboard 410c. Reproducing this issue is simple as below: 1. Trigger hard reset and mount pstore. Will see console-ramoops record in the mounted location which is the current log. 2. Trigger warm reset and mount pstore. Will see the current console-ramoops record instead of previous record. Fixes: b05c950698fe ("pstore/ram: Simplify ramoops_get_next_prz() arguments") Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> [kees: dropped local variable usage] Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore/ram: Avoid NULL deref in ftrace merging failure pathKees Cook
Given corruption in the ftrace records, it might be possible to allocate tmp_prz without assigning prz to it, but still marking it as needing to be freed, which would cause at least a NULL dereference. smatch warnings: fs/pstore/ram.c:340 ramoops_pstore_read() error: we previously assumed 'prz' could be null (see line 255) https://lists.01.org/pipermail/kbuild-all/2018-December/055528.html Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: 2fbea82bbb89 ("pstore: Merge per-CPU ftrace records into one") Cc: "Joel Fernandes (Google)" <joel@joelfernandes.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore: Convert buf_lock to semaphoreKees Cook
Instead of running with interrupts disabled, use a semaphore. This should make it easier for backends that may need to sleep (e.g. EFI) when performing a write: |BUG: sleeping function called from invalid context at kernel/sched/completion.c:99 |in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum |Preemption disabled at: |[<ffffffff99d60512>] pstore_dump+0x72/0x330 |CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45 |Call Trace: | dump_stack+0x4f/0x6a | ___might_sleep.cold.91+0xd3/0xe4 | __might_sleep+0x50/0x90 | wait_for_completion+0x32/0x130 | virt_efi_query_variable_info+0x14e/0x160 | efi_query_variable_store+0x51/0x1a0 | efivar_entry_set_safe+0xa3/0x1b0 | efi_pstore_write+0x109/0x140 | pstore_dump+0x11c/0x330 | kmsg_dump+0xa4/0xd0 | oops_exit+0x22/0x30 ... Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Fixes: 21b3ddd39fee ("efi: Don't use spinlocks for efi vars") Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore/ram: Simplify ramoops_get_next_prz() argumentsJoel Fernandes (Google)
(1) remove type argument from ramoops_get_next_prz() Since we store the type of the prz when we initialize it, we no longer need to pass it again in ramoops_get_next_prz() since we can just use that to setup the pstore record. So lets remove it from the argument list. (2) remove max argument from ramoops_get_next_prz() Looking at the code flow, the 'max' checks are already being done on the prz passed to ramoops_get_next_prz(). Lets remove it to simplify this function and reduce its arguments. (3) further reduce ramoops_get_next_prz() arguments by passing record Both the id and type fields of a pstore_record are set by ramoops_get_next_prz(). So we can just pass a pointer to the pstore_record instead of passing individual elements. This results in cleaner more readable code and fewer lines. In addition lets also remove the 'update' argument since we can detect that. Changes are squashed into a single patch to reduce fixup conflicts. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore: Map PSTORE_TYPE_* to stringsJoel Fernandes (Google)
In later patches we will need to map types to names, so create a constant table for that which can also be used in different parts of old and new code. This saves the type in the PRZ which will be useful in later patches. Instead of having an explicit PSTORE_TYPE_UNKNOWN, just use ..._MAX. This includes removing the now redundant filename templates which can use a single format string. Also, there's no reason to limit the "is it still compressed?" test to only PSTORE_TYPE_DMESG when building the pstorefs filename. Records are zero-initialized, so a backend would need to have explicitly set compressed=1. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore/ram: Report backend assignments with finer granularityKees Cook
In order to more easily perform automated regression testing, this adds pr_debug() calls to report each prz allocation which can then be verified against persistent storage. Specifically, seeing the dividing line between header, data, any ECC bytes. (And the general assignment output is updated to remove the bogus ECC blocksize which isn't actually recorded outside the prz instance.) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03pstore: Avoid duplicate call of persistent_ram_zap()Peng Wang
When initialing a prz, if invalid data is found (no PERSISTENT_RAM_SIG), the function call path looks like this: ramoops_init_prz -> persistent_ram_new -> persistent_ram_post_init -> persistent_ram_zap persistent_ram_zap As we can see, persistent_ram_zap() is called twice. We can avoid this by adding an option to persistent_ram_new(), and only call persistent_ram_zap() when it is needed. Signed-off-by: Peng Wang <wangpeng15@xiaomi.com> [kees: minor tweak to exit path and commit log] Signed-off-by: Kees Cook <keescook@chromium.org>
2018-12-03Merge branch 'for-linus/pstore' into for-next/pstoreKees Cook
2018-11-29pstore/ram: Correctly calculate usable PRZ bytesKees Cook
The actual number of bytes stored in a PRZ is smaller than the bytes requested by platform data, since there is a header on each PRZ. Additionally, if ECC is enabled, there are trailing bytes used as well. Normally this mismatch doesn't matter since PRZs are circular buffers and the leading "overflow" bytes are just thrown away. However, in the case of a compressed record, this rather badly corrupts the results. This corruption was visible with "ramoops.mem_size=204800 ramoops.ecc=1". Any stored crashes would not be uncompressable (producing a pstorefs "dmesg-*.enc.z" file), and triggering errors at boot: [ 2.790759] pstore: crypto_comp_decompress failed, ret = -22! Backporting this depends on commit 70ad35db3321 ("pstore: Convert console write to use ->write_buf") Reported-by: Joel Fernandes <joel@joelfernandes.org> Fixes: b0aad7a99c1d ("pstore: Add compression support to pstore") Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
2018-10-24Merge tag 'pstore-v4.20-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull pstore updates from Kees Cook: "pstore improvements: - refactor init to happen as early as possible again (Joel Fernandes) - improve resource reservation names" * tag 'pstore-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: pstore/ram: Clarify resource reservation labels pstore: Refactor compression initialization pstore: Allocate compression during late_initcall() pstore: Centralize init/exit routines
2018-10-22pstore/ram: Clarify resource reservation labelsKees Cook
When ramoops reserved a memory region in the kernel, it had an unhelpful label of "persistent_memory". When reading /proc/iomem, it would be repeated many times, did not hint that it was ramoops in particular, and didn't clarify very much about what each was used for: 400000000-407ffffff : Persistent Memory (legacy) 400000000-400000fff : persistent_memory 400001000-400001fff : persistent_memory ... 4000ff000-4000fffff : persistent_memory Instead, this adds meaningful labels for how the various regions are being used: 400000000-407ffffff : Persistent Memory (legacy) 400000000-400000fff : ramoops:dump(0/252) 400001000-400001fff : ramoops:dump(1/252) ... 4000fc000-4000fcfff : ramoops:dump(252/252) 4000fd000-4000fdfff : ramoops:console 4000fe000-4000fe3ff : ramoops:ftrace(0/3) 4000fe400-4000fe7ff : ramoops:ftrace(1/3) 4000fe800-4000febff : ramoops:ftrace(2/3) 4000fec00-4000fefff : ramoops:ftrace(3/3) 4000ff000-4000fffff : ramoops:pmsg Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Tested-by: Guenter Roeck <groeck@chromium.org>
2018-10-22pstore: Allocate compression during late_initcall()Joel Fernandes (Google)
ramoops's call of pstore_register() was recently moved to run during late_initcall() because the crypto backend may not have been ready during postcore_initcall(). This meant early-boot crash dumps were not getting caught by pstore any more. Instead, lets allow calls to pstore_register() earlier, and once crypto is ready we can initialize the compression. Reported-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Fixes: cb3bee0369bc ("pstore: Use crypto compress API") [kees: trivial rebase] Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Guenter Roeck <groeck@chromium.org>
2018-09-30pstore/ram: Fix failure-path memory leak in ramoops_initKees Cook
As reported by nixiaoming, with some minor clarifications: 1) memory leak in ramoops_register_dummy(): dummy_data = kzalloc(sizeof(*dummy_data), GFP_KERNEL); but no kfree() if platform_device_register_data() fails. 2) memory leak in ramoops_init(): Missing platform_device_unregister(dummy) and kfree(dummy_data) if platform_driver_register(&ramoops_driver) fails. I've clarified the purpose of ramoops_register_dummy(), and added a common cleanup routine for all three failure paths to call. Reported-by: nixiaoming <nixiaoming@huawei.com> Cc: stable@vger.kernel.org Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-14pstore: Remove bogus format string definitionArnd Bergmann
The pstore conversion to timespec64 introduces its own method of passing seconds into sscanf() and sprintf() type functions to work around the timespec64 definition on 64-bit systems that redefine it to 'timespec'. That hack is now finally getting removed, but that means we get a (harmless) warning once both patches are merged: fs/pstore/ram.c: In function 'ramoops_read_kmsg_hdr': fs/pstore/ram.c:39:29: error: format '%ld' expects argument of type 'long int *', but argument 3 has type 'time64_t *' {aka 'long long int *'} [-Werror=format=] #define RAMOOPS_KERNMSG_HDR "====" ^~~~~~ fs/pstore/ram.c:167:21: note: in expansion of macro 'RAMOOPS_KERNMSG_HDR' This removes the pstore specific workaround and uses the same method that we have in place for all other functions that print a timespec64. Related to this, I found that the kasprintf() output contains an incorrect nanosecond values for any number starting with zeroes, and I adapt the format string accordingly. Link: https://lkml.org/lkml/2018/5/19/115 Link: https://lkml.org/lkml/2018/5/16/1080 Fixes: 0f0d83b99ef7 ("pstore: Convert internal records to timespec64") Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-06-05pstore: Convert internal records to timespec64Kees Cook
This prepares pstore for converting the VFS layer to timespec64. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
2018-03-09pstore: Use crypto compress APIGeliang Tang
In the pstore compression part, we use zlib/lzo/lz4/lz4hc/842 compression algorithm API to implement pstore compression backends. But there are many repeat codes in these implementations. This patch uses crypto compress API to simplify these codes. 1) rewrite allocate_buf_for_compression, free_buf_for_compression, pstore_compress, pstore_decompress functions using crypto compress API. 2) drop compress, decompress, allocate, free functions in pstore_zbackend, and add zbufsize function to get each different compress buffer size. 3) use late_initcall to call ramoops_init later, to make sure the crypto subsystem has already initialized. 4) use 'unsigned int' type instead of 'size_t' in pstore_compress, pstore_decompress functions' length arguments. 5) rename 'zlib' to 'deflate' to follow the crypto API's name convention. Signed-off-by: Geliang Tang <geliangtang@gmail.com> [kees: tweaked error messages on allocation failures and Kconfig help] Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31pstore: Populate pstore record->time fieldKees Cook
The current time will be initially available in the record->time field for all pstore_read() and pstore_write() calls. Backends can either update the field during read(), or use the field during write() instead of fetching time themselves. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-10Merge tag 'hwparam-20170420' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull hw lockdown support from David Howells: "Annotation of module parameters that configure hardware resources including ioports, iomem addresses, irq lines and dma channels. This allows a future patch to prohibit the use of such module parameters to prevent that hardware from being abused to gain access to the running kernel image as part of locking the kernel down under UEFI secure boot conditions. Annotations are made by changing: module_param(n, t, p) module_param_named(n, v, t, p) module_param_array(n, t, m, p) to: module_param_hw(n, t, hwtype, p) module_param_hw_named(n, v, t, hwtype, p) module_param_hw_array(n, t, hwtype, m, p) where the module parameter refers to a hardware setting hwtype specifies the type of the resource being configured. This can be one of: ioport Module parameter configures an I/O port iomem Module parameter configures an I/O mem address ioport_or_iomem Module parameter could be either (runtime set) irq Module parameter configures an I/O port dma Module parameter configures a DMA channel dma_addr Module parameter configures a DMA buffer address other Module parameter configures some other value Note that the hwtype is compile checked, but not currently stored (the lockdown code probably won't require it). It is, however, there for future use. A bonus is that the hwtype can also be used for grepping. The intention is for the kernel to ignore or reject attempts to set annotated module parameters if lockdown is enabled. This applies to options passed on the boot command line, passed to insmod/modprobe or direct twiddling in /sys/module/ parameter files. The module initialisation then needs to handle the parameter not being set, by (1) giving an error, (2) probing for a value or (3) using a reasonable default. What I can't do is just reject a module out of hand because it may take a hardware setting in the module parameters. Some important modules, some ipmi stuff for instance, both probe for hardware and allow hardware to be manually specified; if the driver is aborts with any error, you don't get any ipmi hardware. Further, trying to do this entirely in the module initialisation code doesn't protect against sysfs twiddling. [!] Note that in and of itself, this series of patches should have no effect on the the size of the kernel or code execution - that is left to a patch in the next series to effect. It does mark annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in an already existing field" * tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits) Annotate hardware config module parameters in sound/pci/ Annotate hardware config module parameters in sound/oss/ Annotate hardware config module parameters in sound/isa/ Annotate hardware config module parameters in sound/drivers/ Annotate hardware config module parameters in fs/pstore/ Annotate hardware config module parameters in drivers/watchdog/ Annotate hardware config module parameters in drivers/video/ Annotate hardware config module parameters in drivers/tty/ Annotate hardware config module parameters in drivers/staging/vme/ Annotate hardware config module parameters in drivers/staging/speakup/ Annotate hardware config module parameters in drivers/staging/media/ Annotate hardware config module parameters in drivers/scsi/ Annotate hardware config module parameters in drivers/pcmcia/ Annotate hardware config module parameters in drivers/pci/hotplug/ Annotate hardware config module parameters in drivers/parport/ Annotate hardware config module parameters in drivers/net/wireless/ Annotate hardware config module parameters in drivers/net/wan/ Annotate hardware config module parameters in drivers/net/irda/ Annotate hardware config module parameters in drivers/net/hamradio/ Annotate hardware config module parameters in drivers/net/ethernet/ ...