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path: root/drivers/char/tpm/tpm-dev.c
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2026-07-12tpm: Make the TPM character devices non-seekableJaewon Yang
The TPM character devices expose a sequential command/response interface, but their open handlers leave FMODE_PREAD and FMODE_PWRITE enabled. After a command leaves a response pending, pread(fd, buf, 16, 0x1400) passes 0x1400 as *off to tpm_common_read(). The transfer length is bounded by response_length, but the offset is used unchecked when forming data_buffer + *off. A sufficiently large offset therefore causes an out-of-bounds heap read through copy_to_user() and, if the copy succeeds, an out-of-bounds zero-write through the following memset(). Positional I/O does not provide coherent semantics for this interface. An arbitrary pread offset cannot represent how much of a response has been consumed sequentially. The write callback always stores a command at the start of data_buffer, while pwrite() does not update file->f_pos and can leave the sequential read cursor stale. Call nonseekable_open() from both open handlers. This removes FMODE_PREAD and FMODE_PWRITE, causing positional reads and writes to fail with -ESPIPE before reaching the TPM callbacks, and explicitly marks the files non-seekable. Normal read() and write() continue to use the existing sequential f_pos cursor, leaving the response state machine unchanged. Tested on Linux 6.12 with KASAN and a swtpm TPM2 device: - sequential partial reads returned the complete response - pread() and preadv() with offset 0x1400 returned -ESPIPE - pwrite() and pwritev() with offset zero returned -ESPIPE - the pending response remained intact after the rejected operations - a subsequent normal command/response cycle completed normally - no KASAN report was produced. Fixes: 9488585b21be ("tpm: add support for partial reads") Link: https://lore.kernel.org/all/20260710090217.191289-1-yong010301@gmail.com/ Cc: stable@vger.kernel.org Signed-off-by: Jaewon Yang <yong010301@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2024-09-27[tree-wide] finally take no_llseek outAl Viro
no_llseek had been defined to NULL two years ago, in commit 868941b14441 ("fs: remove no_llseek") To quote that commit, At -rc1 we'll need do a mechanical removal of no_llseek - git grep -l -w no_llseek | grep -v porting.rst | while read i; do sed -i '/\<no_llseek\>/d' $i done would do it. Unfortunately, that hadn't been done. Linus, could you do that now, so that we could finally put that thing to rest? All instances are of the form .llseek = no_llseek, so it's obviously safe. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441Thomas 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 as published by the free software foundation version 2 of the license extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 315 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-05tpm: add support for nonblocking operationTadeusz Struk
Currently the TPM driver only supports blocking calls, which doesn't allow asynchronous IO operations to the TPM hardware. This patch changes it and adds support for nonblocking write and a new poll function to enable applications, which want to take advantage of this. Tested-by: Philip Tricca <philip.b.tricca@intel.com> Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off--by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-10-05tpm: add ptr to the tpm_space struct to file_privTadeusz Struk
Add a ptr to struct tpm_space to the file_priv and consolidate of the write operations for the two interfaces. Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com> Tested-by: Philip Tricca <philip.b.tricca@intel.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off--by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-04-03tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.cJames Bottomley
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-04-03tpm: infrastructure for TPM spacesJarkko Sakkinen
Added an ability to virtualize TPM commands into an isolated context that we call a TPM space because the word context is already heavily used in the TPM specification. Both the handle areas and bodies (where necessary) are virtualized. The mechanism works by adding a new parameter struct tpm_space to the tpm_transmit() function. This new structure contains the list of virtual handles and a buffer of page size (currently) for backing storage. When tpm_transmit() is called with a struct tpm_space instance it will execute the following sequence: 1. Take locks. 2. Load transient objects from the backing storage by using ContextLoad and map virtual handles to physical handles. 3. Perform the transaction. 4. Save transient objects to backing storage by using ContextSave and map resulting physical handle to virtual handle if there is such. This commit does not implement virtualization support for hmac and policy sessions. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Tested-by: James Bottomley <James.Bottomley@HansenPartnership.com> Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2017-02-03tpm: Begin the process to deprecate user_read_timerJason Gunthorpe
For a long time the cdev read/write interface had this strange idea that userspace had to read the result within 60 seconds otherwise it is discarded. Perhaps this made sense under some older locking regime, but in the modern kernel it is not required and is just dangerous. Since something may be relying on this, double the timeout and print a warning. We can remove the code in a few years, but this should be enough to prevent new users. Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-09-15tpm: fix a race condition in tpm2_unseal_trusted()Jarkko Sakkinen
Unseal and load operations should be done as an atomic operation. This commit introduces unlocked tpm_transmit() so that tpm2_unseal_trusted() can do the locking by itself. Fixes: 0fe5480303a1 ("keys, trusted: seal/unseal with TPM 2.0 chips") Cc: stable@vger.kernel.org Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
2016-06-25tpm: Provide strong locking for device removalJason Gunthorpe
Add a read/write semaphore around the ops function pointers so ops can be set to null when the driver un-registers. Previously the tpm core expected module locking to be enough to ensure that tpm_unregister could not be called during certain times, however that hasn't been sufficient for a long time. Introduce a read/write semaphore around 'ops' so the core can set it to null when unregistering. This provides a strong fence around the driver callbacks, guaranteeing to the driver that no callbacks are running or will run again. For now the ops_lock is placed very high in the call stack, it could be pushed down and made more granular in future if necessary. Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-06-25tpm: Get rid of chip->pdevJason Gunthorpe
This is a hold over from before the struct device conversion. - All prints should be using &chip->dev, which is the Linux standard. This changes prints to use tpm0 as the device name, not the PnP/etc ID. - The few places involving sysfs/modules that really do need the parent just use chip->dev.parent instead - We no longer need to get_device(pdev) in any places since it is no longer used by any of the code. The kref on the parent is held by the device core during device_add and dropped in device_del Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2015-01-17tpm: device class for tpmJarkko Sakkinen
Added own device class for TPM. Uses MISC_MAJOR:TPM_MINOR for the first character device in order to retain backwards compatibility. Added tpm_dev_release() back attached to the character device. I've been running this code now for a while on my laptop (Lenovo T430S) TrouSerS works perfectly without modifications. I don't believe it breaks anything significantly. The sysfs attributes that have been placed under the wrong place and are against sysfs-rules.txt should be probably left to stagnate under platform device directory and start defining new sysfs attributes to the char device directory. Guidelines for future TPM sysfs attributes should be probably along the lines of - Single flat set of mandatory sysfs attributes. For example, current PPI interface is way way too rich when you only want to use it to clear and activate the TPM. - Define sysfs attribute if and only if there's no way to get the value from ring-3. No attributes for TPM properties. It's just unnecessary maintenance hurdle that we don't want. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com> Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-01-17tpm: rename chip->dev to chip->pdevJarkko Sakkinen
Rename chip->dev to chip->pdev to make it explicit that this not the character device but actually represents the platform device. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com> Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Reviewed-by: Peter Huewe <peterhuewe@gmx.de> Tested-by: Scot Doyle <lkml14@scotdoyle.com> Tested-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-01-06tpm: Make tpm-dev allocate a per-file structureJason Gunthorpe
This consolidates everything that is only used within tpm-dev.c into tpm-dev.c and out of the publicly visible struct tpm_chip. The per-file allocation lays the ground work for someday fixing the strange forced O_EXCL behaviour of the current code. Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com> Reviewed-by: Ashley Lai <adlai@linux.vnet.ibm.com> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-01-06tpm: Pull everything related to /dev/tpmX into tpm-dev.cJason Gunthorpe
CLASS-dev.c is a common idiom for Linux subsystems This pulls all the code related to the miscdev into tpm-dev.c and makes it static. The identical file_operation structs in the drivers are purged and the tpm common code unconditionally creates the miscdev. Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com> Reviewed-by: Ashley Lai <adlai@linux.vnet.ibm.com> [phuewe: tpm_dev_release is now used only in this file, thus the EXPORT_SYMBOL can be dropped and the function be marked as static. It has no other in-kernel users] Signed-off-by: Peter Huewe <peterhuewe@gmx.de>