diff options
| author | Jarkko Sakkinen <jarkko.sakkinen@tuni.fi> | 2023-05-16 01:25:54 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-07-27 08:37:34 +0200 |
| commit | 86b9820395f226b8f33cbae9599deebf8af1ce72 (patch) | |
| tree | c970561855064675868d1a4f4512c57bf611338f /drivers/char | |
| parent | 96a16069a81d05b5e3c8943acd8676b1ddae0956 (diff) | |
tpm: tpm_vtpm_proxy: fix a race condition in /dev/vtpmx creation
commit f4032d615f90970d6c3ac1d9c0bce3351eb4445c upstream.
/dev/vtpmx is made visible before 'workqueue' is initialized, which can
lead to a memory corruption in the worst case scenario.
Address this by initializing 'workqueue' as the very first step of the
driver initialization.
Cc: stable@vger.kernel.org
Fixes: 6f99612e2500 ("tpm: Proxy driver for supporting multiple emulated TPMs")
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@tuni.fi>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/tpm/tpm_vtpm_proxy.c | 30 |
1 files changed, 7 insertions, 23 deletions
diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c index 2f6e087ec496..ff6b88fa4f47 100644 --- a/drivers/char/tpm/tpm_vtpm_proxy.c +++ b/drivers/char/tpm/tpm_vtpm_proxy.c @@ -693,37 +693,21 @@ static struct miscdevice vtpmx_miscdev = { .fops = &vtpmx_fops, }; -static int vtpmx_init(void) -{ - return misc_register(&vtpmx_miscdev); -} - -static void vtpmx_cleanup(void) -{ - misc_deregister(&vtpmx_miscdev); -} - static int __init vtpm_module_init(void) { int rc; - rc = vtpmx_init(); - if (rc) { - pr_err("couldn't create vtpmx device\n"); - return rc; - } - workqueue = create_workqueue("tpm-vtpm"); if (!workqueue) { pr_err("couldn't create workqueue\n"); - rc = -ENOMEM; - goto err_vtpmx_cleanup; + return -ENOMEM; } - return 0; - -err_vtpmx_cleanup: - vtpmx_cleanup(); + rc = misc_register(&vtpmx_miscdev); + if (rc) { + pr_err("couldn't create vtpmx device\n"); + destroy_workqueue(workqueue); + } return rc; } @@ -731,7 +715,7 @@ err_vtpmx_cleanup: static void __exit vtpm_module_exit(void) { destroy_workqueue(workqueue); - vtpmx_cleanup(); + misc_deregister(&vtpmx_miscdev); } module_init(vtpm_module_init); |