Re: [PATCH v2 0/4] tpm: some tpm small fixes.
From: Jarkko Sakkinen
Date: Sat Oct 10 2026 - 00:37:53 EST
On Fri, Oct 09, 2026 at 09:01:05AM +0800, Pei Xiao wrote:
>
>
> 在 2026/10/9 01:51, Jarkko Sakkinen 写道:
> > On Thu, Oct 08, 2026 at 09:16:19AM +0800, Pei Xiao wrote:
> >> This series fixes several small issues found during a code review of
> >> drivers/char/tpm:
> >>
> >> 1. tpm_ppi: tpm_show_ppi_response() stores its return value in an
> >> acpi_status (a u32 typedef), so error codes such as -EINVAL reach
> >> user space as huge positive values. Declare the variable as
> >> ssize_t to match the show callback's return type.
> >>
> >> 2. tpm_nsc: tpm_nsc_remove() doubles as the release callback of the
> >> hand-created platform device and dereferences the chip drvdata
> >> unconditionally; init failures before tpmm_chip_alloc() crash
> >> module load. Return early when the chip has not been created.
> >>
> >> 3. tpm_nsc: the cleanup runs twice on module exit because
> >> tpm_nsc_remove() is both the explicit cleanup and the device
> >> release callback; the second run operates on an already freed
> >> chip. Stop overriding the release callback, which also stops the
> >> platform object allocation from leaking.
> >>
> >> 4. tpm_dev: a zero-length read() discards a pending response,
> >> breaking the command/response pairing of the TPM character
> >> devices, although POSIX requires zero-count reads to have no side
> >> effects. Return early on a zero count.
> >>
> >> chhanges in v2:
> >> 1.add reviewed-by tag
> >> 2.remove patch 5:
> >> make the tpm_init() error messages consistently prefixed with "tpm: " and
> >> report the actual failure of tpm_dev_common_init().
> >> 3.modify patch 1 git commit information.
> >>
> >> Pei Xiao (4):
> >> tpm: tpm_ppi: fix zero-extension of negative error codes
> >> tpm: tpm_nsc: fix NULL pointer dereference on init failure
> >> tpm: tpm_nsc: stop using the cleanup callback as dev.release
> >> tpm: fix zero-length read discarding the pending response
> >>
> >> drivers/char/tpm/tpm-dev-common.c | 3 +++
> >> drivers/char/tpm/tpm_nsc.c | 8 ++++++--
> >> drivers/char/tpm/tpm_ppi.c | 2 +-
> >> 3 files changed, 10 insertions(+), 3 deletions(-)
> >>
> >> --
> >> 2.25.1
> >>
> >
> > Right, so I've already applied some of the patches so I'm a bit
> > confused what to do with this.
> >
> > See:
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git/log/
> >
> > Is there something wrong in the ones that I already applied?
> hi Jarkko,
> Because this patch ("tpm: tpm_ppi: fix zero-extension of negative
> error codes") did not pass review, I resend a v2 version that includes
> the patches that have already passed review and carries their
> Reviewed-by tags.
Hey, no worries, I'm just sanity checking (and thus asking, that's
all). Nothing you did particularly wrong.
> Pei.
> thanks!>
Br, Jarkko