5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: He Zhe zhe.he@windriver.com
commit 4e60131d0d36af65ab9c9144f4f163fe97ae36e8 upstream.
hpet_compat_ioctl and read file operations failed to handle parameters from 32-bit userspace and thus samples/timers/hpet_example.c fails as below.
root@intel-x86-64:~# ./hpet_example-32.out poll /dev/hpet 1 2 -hpet: executing poll hpet_poll: HPET_IRQFREQ failed
This patch fixes cmd and arg handling in hpet_compat_ioctl and adds compat handling for 32-bit userspace in hpet_read.
hpet_example now shows that it works for both 64-bit and 32-bit.
root@intel-x86-64:~# ./hpet_example-32.out poll /dev/hpet 1 2 -hpet: executing poll hpet_poll: info.hi_flags 0x0 hpet_poll: expired time = 0xf4298 hpet_poll: revents = 0x1 hpet_poll: data 0x1 hpet_poll: expired time = 0xf4235 hpet_poll: revents = 0x1 hpet_poll: data 0x1 root@intel-x86-64:~# ./hpet_example-64.out poll /dev/hpet 1 2 -hpet: executing poll hpet_poll: info.hi_flags 0x0 hpet_poll: expired time = 0xf42a1 hpet_poll: revents = 0x1 hpet_poll: data 0x1 hpet_poll: expired time = 0xf4232 hpet_poll: revents = 0x1 hpet_poll: data 0x1
Cc: stable@vger.kernel.org Signed-off-by: He Zhe zhe.he@windriver.com Fixes: 54066a57c584 ("hpet: kill BKL, add compat_ioctl") Reviewed-by: Arnd Bergmann arnd@arndb.de Link: https://lore.kernel.org/r/20240606123908.738733-1-zhe.he@windriver.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/char/hpet.c | 34 +++++++++++++++++++++++++++++----- 1 file changed, 29 insertions(+), 5 deletions(-)
--- a/drivers/char/hpet.c +++ b/drivers/char/hpet.c @@ -304,8 +304,13 @@ hpet_read(struct file *file, char __user if (!devp->hd_ireqfreq) return -EIO;
- if (count < sizeof(unsigned long)) - return -EINVAL; + if (in_compat_syscall()) { + if (count < sizeof(compat_ulong_t)) + return -EINVAL; + } else { + if (count < sizeof(unsigned long)) + return -EINVAL; + }
add_wait_queue(&devp->hd_waitqueue, &wait);
@@ -329,9 +334,16 @@ hpet_read(struct file *file, char __user schedule(); }
- retval = put_user(data, (unsigned long __user *)buf); - if (!retval) - retval = sizeof(unsigned long); + if (in_compat_syscall()) { + retval = put_user(data, (compat_ulong_t __user *)buf); + if (!retval) + retval = sizeof(compat_ulong_t); + } else { + retval = put_user(data, (unsigned long __user *)buf); + if (!retval) + retval = sizeof(unsigned long); + } + out: __set_current_state(TASK_RUNNING); remove_wait_queue(&devp->hd_waitqueue, &wait); @@ -686,12 +698,24 @@ struct compat_hpet_info { unsigned short hi_timer; };
+/* 32-bit types would lead to different command codes which should be + * translated into 64-bit ones before passed to hpet_ioctl_common + */ +#define COMPAT_HPET_INFO _IOR('h', 0x03, struct compat_hpet_info) +#define COMPAT_HPET_IRQFREQ _IOW('h', 0x6, compat_ulong_t) + static long hpet_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct hpet_info info; int err;
+ if (cmd == COMPAT_HPET_INFO) + cmd = HPET_INFO; + + if (cmd == COMPAT_HPET_IRQFREQ) + cmd = HPET_IRQFREQ; + mutex_lock(&hpet_mutex); err = hpet_ioctl_common(file->private_data, cmd, arg, &info); mutex_unlock(&hpet_mutex);