• Ard Biesheuvel's avatar
    tpm: Avoid function type cast of put_device() · e10de46b
    Ard Biesheuvel authored
    
    
    The TPM code registers put_device() as a devm cleanup handler, and casts
    the reference to the right function pointer type for this to be
    permitted by the compiler.
    
    However, under kCFI, this is rejected at runtime, resulting in a splat
    like
    
       CFI failure at devm_action_release+0x24/0x3c (target: put_device+0x0/0x24; expected type: 0xa488ebfc)
       Internal error: Oops - CFI: 0000000000000000 [#1] PREEMPT SMP
       Modules linked in:  ...
       CPU: 20 PID: 454 Comm: systemd-udevd Not tainted 6.1.0-rc1+ #51
       Hardware name: Socionext SynQuacer E-series DeveloperBox, BIOS build #1 Oct  3 2022
       pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
       pc : devm_action_release+0x24/0x3c
       lr : devres_release_all+0xb4/0x114
       sp : ffff800009bb3630
       x29: ffff800009bb3630 x28: 0000000000000000 x27: 0000000000000011
       x26: ffffaa6f9922c0c8 x25: 0000000000000002 x24: 000000000000000f
       x23: ffff800009bb3648 x22: ffff7aefc3be2100 x21: ffff7aefc3be2e00
       x20: 0000000000000005 x19: ffff7aefc1e1ec10 x18: ffff800009af70a8
       x17: 00000000a488ebfc x16: 0000000094ee7df3 x15: 0000000000000000
       x14: 4075c5c2ef7affff x13: e46a91c5c5e2ef42 x12: ffff7aefc2c57540
       x11: 0000000000000001 x10: 0000000000000001 x9 : 0000000100000000
       x8 : ffffaa6fa09b39b4 x7 : 7f7f7f7f7f7f7f7f x6 : 8000000000000000
       x5 : 000000008020000e x4 : ffff7aefc2c57500 x3 : ffff800009bb3648
       x2 : ffff800009bb3648 x1 : ffff7aefc3be2e80 x0 : ffff7aefc3bb7000
       Call trace:
        devm_action_release+0x24/0x3c
        devres_release_all+0xb4/0x114
        really_probe+0xb0/0x49c
        __driver_probe_device+0x114/0x180
        driver_probe_device+0x48/0x1ec
        __driver_attach+0x118/0x284
        bus_for_each_dev+0x94/0xe4
        driver_attach+0x24/0x34
        bus_add_driver+0x10c/0x220
        driver_register+0x78/0x118
        __platform_driver_register+0x24/0x34
        init_module+0x20/0xfe4 [tpm_tis_synquacer]
        do_one_initcall+0xd4/0x248
        do_init_module+0x44/0x28c
        load_module+0x16b4/0x1920
    
    Fix this by going through a helper function of the correct type.
    Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
    Reviewed-by: default avatarKees Cook <keescook@chromium.org>
    Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
    Reviewed-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
    Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
    e10de46b
tpm-chip.c 13.9 KB