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: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
drivers/char/tpm/tpm-chip.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 783d65fc71f0..741d8f3e8fb3 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -373,6 +373,11 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
}
EXPORT_SYMBOL_GPL(tpm_chip_alloc);
+static void tpm_put_device(void *dev)
+{
+ put_device(dev);
+}
+
/**
* tpmm_chip_alloc() - allocate a new struct tpm_chip instance
* @pdev: parent device to which the chip is associated
@@ -391,7 +396,7 @@ struct tpm_chip *tpmm_chip_alloc(struct device *pdev,
return chip;
rc = devm_add_action_or_reset(pdev,
- (void (*)(void *)) put_device,
+ tpm_put_device,
&chip->dev);
if (rc)
return ERR_PTR(rc);
--
2.35.1
