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path: root/drivers/char/tpm/tpmrm-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>
2020-07-24tpm: Unify the mismatching TPM space buffer sizesJarkko Sakkinen
The size of the buffers for storing context's and sessions can vary from arch to arch as PAGE_SIZE can be anything between 4 kB and 256 kB (the maximum for PPC64). Define a fixed buffer size set to 16 kB. This should be enough for most use with three handles (that is how many we allow at the moment). Parametrize the buffer size while doing this, so that it is easier to revisit this later on if required. Cc: stable@vger.kernel.org Reported-by: Stefan Berger <stefanb@linux.ibm.com> Fixes: 745b361e989a ("tpm: infrastructure for TPM spaces") Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com> Tested-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 505Thomas Gleixner
Based on 1 normalized pattern(s): gplv2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 58 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081207.556988620@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>
2017-06-13tpm, tpmrm: Mark tpmrm_write as staticPeter Huewe
sparse complains that tpmrm_write can be made static, and since it is right we make it static. Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-04-03tpm2: add session handle context saving and restoring to the space codeJames Bottomley
Sessions are different from transient objects in that their handles may not be virtualized (because they're used for some hmac calculations). Additionally when a session is context saved, a vestigial memory remains in the TPM and if it is also flushed, that will be lost and the session context will refuse to load next time, so the code is updated to flush only transient objects after a context save. Add a separate array (chip->session_tbl) to save and restore sessions by handle. Use the failure of a context save or load to signal that the session has been flushed from the TPM and we can remove its memory from chip->session_tbl. Sessions are also isolated during each instance of a tpm space. This means that spaces shouldn't be able to see each other's sessions and is enforced by ensuring that a space user may only refer to sessions handles that are present in their own chip->session_tbl. Finally when a space is closed, all the sessions belonging to it should be flushed so the handles may be re-used by other spaces. Note that if we get a session save or load error, all sessions are effectively flushed. Even though we restore the session buffer, all the old sessions will refuse to load after the flush and they'll be purged from our session memory. This means that while transient context handling is still soft in the face of errors, session handling is hard (any failure of the model means all sessions are lost). Fixes-from: Colin Ian King <colin.king@canonical.com> 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: expose spaces via a device link /dev/tpmrm<n>James Bottomley
Currently the tpm spaces are not exposed to userspace. Make this exposure via a separate device, which can now be opened multiple times because each read/write transaction goes separately via the space. Concurrency is protected by the chip->tpm_mutex for each read/write transaction separately. The TPM is cleared of all transient objects by the time the mutex is dropped, so there should be no interference between the kernel and userspace. 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>