From c2a49fe8eeef301b40d0c8065d817c5425d31b11 Mon Sep 17 00:00:00 2001 From: Matt Ranostay Date: Fri, 10 Mar 2017 15:19:45 -0800 Subject: [PATCH] pps: fix padding issue with PPS_FETCH for ioctl_compat Issue is that x86 32-bit aligns to 4-bytes instead of 8-bytes so this patchset works around the issue and corrects the data returned in pps_fdata_compat. Acked-by: Rodolfo Giometti Signed-off-by: Matt Ranostay Signed-off-by: Greg Kroah-Hartman --- drivers/pps/pps.c | 110 ++++++++++++++++++++++++++++----------- include/uapi/linux/pps.h | 19 +++++++ 2 files changed, 98 insertions(+), 31 deletions(-) diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c index 452ead5a5e52..6eb0db37dd88 100644 --- a/drivers/pps/pps.c +++ b/drivers/pps/pps.c @@ -64,6 +64,43 @@ static int pps_cdev_fasync(int fd, struct file *file, int on) return fasync_helper(fd, file, on, &pps->async_queue); } +static int pps_cdev_pps_fetch(struct pps_device *pps, struct pps_fdata *fdata) +{ + unsigned int ev = pps->last_ev; + int err = 0; + + /* Manage the timeout */ + if (fdata->timeout.flags & PPS_TIME_INVALID) + err = wait_event_interruptible(pps->queue, + ev != pps->last_ev); + else { + unsigned long ticks; + + dev_dbg(pps->dev, "timeout %lld.%09d\n", + (long long) fdata->timeout.sec, + fdata->timeout.nsec); + ticks = fdata->timeout.sec * HZ; + ticks += fdata->timeout.nsec / (NSEC_PER_SEC / HZ); + + if (ticks != 0) { + err = wait_event_interruptible_timeout( + pps->queue, + ev != pps->last_ev, + ticks); + if (err == 0) + return -ETIMEDOUT; + } + } + + /* Check for pending signals */ + if (err == -ERESTARTSYS) { + dev_dbg(pps->dev, "pending signal caught\n"); + return -EINTR; + } + + return 0; +} + static long pps_cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -144,7 +181,6 @@ static long pps_cdev_ioctl(struct file *file, case PPS_FETCH: { struct pps_fdata fdata; - unsigned int ev; dev_dbg(pps->dev, "PPS_FETCH\n"); @@ -152,36 +188,9 @@ static long pps_cdev_ioctl(struct file *file, if (err) return -EFAULT; - ev = pps->last_ev; - - /* Manage the timeout */ - if (fdata.timeout.flags & PPS_TIME_INVALID) - err = wait_event_interruptible(pps->queue, - ev != pps->last_ev); - else { - unsigned long ticks; - - dev_dbg(pps->dev, "timeout %lld.%09d\n", - (long long) fdata.timeout.sec, - fdata.timeout.nsec); - ticks = fdata.timeout.sec * HZ; - ticks += fdata.timeout.nsec / (NSEC_PER_SEC / HZ); - - if (ticks != 0) { - err = wait_event_interruptible_timeout( - pps->queue, - ev != pps->last_ev, - ticks); - if (err == 0) - return -ETIMEDOUT; - } - } - - /* Check for pending signals */ - if (err == -ERESTARTSYS) { - dev_dbg(pps->dev, "pending signal caught\n"); - return -EINTR; - } + err = pps_cdev_pps_fetch(pps, &fdata); + if (err) + return err; /* Return the fetched timestamp */ spin_lock_irq(&pps->lock); @@ -246,8 +255,47 @@ static long pps_cdev_ioctl(struct file *file, static long pps_cdev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { + struct pps_device *pps = file->private_data; + void __user *uarg = (void __user *) arg; + cmd = _IOC(_IOC_DIR(cmd), _IOC_TYPE(cmd), _IOC_NR(cmd), sizeof(void *)); + if (cmd == PPS_FETCH) { + struct pps_fdata_compat compat; + struct pps_fdata fdata; + int err; + + dev_dbg(pps->dev, "PPS_FETCH\n"); + + err = copy_from_user(&compat, uarg, sizeof(struct pps_fdata_compat)); + if (err) + return -EFAULT; + + memcpy(&fdata.timeout, &compat.timeout, + sizeof(struct pps_ktime_compat)); + + err = pps_cdev_pps_fetch(pps, &fdata); + if (err) + return err; + + /* Return the fetched timestamp */ + spin_lock_irq(&pps->lock); + + compat.info.assert_sequence = pps->assert_sequence; + compat.info.clear_sequence = pps->clear_sequence; + compat.info.current_mode = pps->current_mode; + + memcpy(&compat.info.assert_tu, &pps->assert_tu, + sizeof(struct pps_ktime_compat)); + memcpy(&compat.info.clear_tu, &pps->clear_tu, + sizeof(struct pps_ktime_compat)); + + spin_unlock_irq(&pps->lock); + + return copy_to_user(uarg, &compat, + sizeof(struct pps_fdata_compat)) ? -EFAULT : 0; + } + return pps_cdev_ioctl(file, cmd, arg); } #else diff --git a/include/uapi/linux/pps.h b/include/uapi/linux/pps.h index a9bb1d93451a..c1cb3825a8bc 100644 --- a/include/uapi/linux/pps.h +++ b/include/uapi/linux/pps.h @@ -55,6 +55,12 @@ struct pps_ktime { __s32 nsec; __u32 flags; }; + +struct pps_ktime_compat { + __s64 sec; + __s32 nsec; + __u32 flags; +} __attribute__((packed, aligned(4))); #define PPS_TIME_INVALID (1<<0) /* used to specify timeout==NULL */ struct pps_kinfo { @@ -65,6 +71,14 @@ struct pps_kinfo { int current_mode; /* current mode bits */ }; +struct pps_kinfo_compat { + __u32 assert_sequence; /* seq. num. of assert event */ + __u32 clear_sequence; /* seq. num. of clear event */ + struct pps_ktime_compat assert_tu; /* time of assert event */ + struct pps_ktime_compat clear_tu; /* time of clear event */ + int current_mode; /* current mode bits */ +}; + struct pps_kparams { int api_version; /* API version # */ int mode; /* mode bits */ @@ -114,6 +128,11 @@ struct pps_fdata { struct pps_ktime timeout; }; +struct pps_fdata_compat { + struct pps_kinfo_compat info; + struct pps_ktime_compat timeout; +}; + struct pps_bind_args { int tsformat; /* format of time stamps */ int edge; /* selected event type */