From 10100ffd5f6584298b72f9fe26f32cf02abfb8b0 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 30 May 2020 00:40:27 +0100 Subject: scsi: hpsa: Get rid of compat_alloc_user_space() No need for building a native struct on kernel stack, copying it to userland one, then calling hpsa_ioctl() which copies it back into _another_ instance of the same struct. Link: https://lore.kernel.org/r/20200529234028.46373-3-viro@ZenIV.linux.org.uk Acked-by: Don Brace Tested-by: Don Brace Signed-off-by: Al Viro Signed-off-by: Martin K. Petersen --- drivers/scsi/hpsa.c | 80 ++++++++++++++++++++++++----------------------------- 1 file changed, 36 insertions(+), 44 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 64fd97272109..c7fbe56891ef 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -254,6 +254,10 @@ static irqreturn_t do_hpsa_intr_intx(int irq, void *dev_id); static irqreturn_t do_hpsa_intr_msi(int irq, void *dev_id); static int hpsa_ioctl(struct scsi_device *dev, unsigned int cmd, void __user *arg); +static int hpsa_passthru_ioctl(struct ctlr_info *h, + IOCTL_Command_struct *iocommand); +static int hpsa_big_passthru_ioctl(struct ctlr_info *h, + BIG_IOCTL_Command_struct *ioc); #ifdef CONFIG_COMPAT static int hpsa_compat_ioctl(struct scsi_device *dev, unsigned int cmd, @@ -6217,75 +6221,63 @@ static void cmd_free(struct ctlr_info *h, struct CommandList *c) static int hpsa_ioctl32_passthru(struct scsi_device *dev, unsigned int cmd, void __user *arg) { - IOCTL32_Command_struct __user *arg32 = - (IOCTL32_Command_struct __user *) arg; + struct ctlr_info *h = sdev_to_hba(dev); + IOCTL32_Command_struct __user *arg32 = arg; IOCTL_Command_struct arg64; - IOCTL_Command_struct __user *p = compat_alloc_user_space(sizeof(arg64)); int err; u32 cp; - memset(&arg64, 0, sizeof(arg64)); - err = 0; - err |= copy_from_user(&arg64.LUN_info, &arg32->LUN_info, - sizeof(arg64.LUN_info)); - err |= copy_from_user(&arg64.Request, &arg32->Request, - sizeof(arg64.Request)); - err |= copy_from_user(&arg64.error_info, &arg32->error_info, - sizeof(arg64.error_info)); - err |= get_user(arg64.buf_size, &arg32->buf_size); - err |= get_user(cp, &arg32->buf); - arg64.buf = compat_ptr(cp); - err |= copy_to_user(p, &arg64, sizeof(arg64)); + if (!arg) + return -EINVAL; - if (err) + memset(&arg64, 0, sizeof(arg64)); + if (copy_from_user(&arg64, arg32, offsetof(IOCTL_Command_struct, buf))) + return -EFAULT; + if (get_user(cp, &arg32->buf)) return -EFAULT; + arg64.buf = compat_ptr(cp); - err = hpsa_ioctl(dev, CCISS_PASSTHRU, p); + if (atomic_dec_if_positive(&h->passthru_cmds_avail) < 0) + return -EAGAIN; + err = hpsa_passthru_ioctl(h, &arg64); + atomic_inc(&h->passthru_cmds_avail); if (err) return err; - err |= copy_in_user(&arg32->error_info, &p->error_info, - sizeof(arg32->error_info)); - if (err) + if (copy_to_user(&arg32->error_info, &arg64.error_info, + sizeof(arg32->error_info))) return -EFAULT; - return err; + return 0; } static int hpsa_ioctl32_big_passthru(struct scsi_device *dev, unsigned int cmd, void __user *arg) { - BIG_IOCTL32_Command_struct __user *arg32 = - (BIG_IOCTL32_Command_struct __user *) arg; + struct ctlr_info *h = sdev_to_hba(dev); + BIG_IOCTL32_Command_struct __user *arg32 = arg; BIG_IOCTL_Command_struct arg64; - BIG_IOCTL_Command_struct __user *p = - compat_alloc_user_space(sizeof(arg64)); int err; u32 cp; + if (!arg) + return -EINVAL; memset(&arg64, 0, sizeof(arg64)); - err = 0; - err |= copy_from_user(&arg64.LUN_info, &arg32->LUN_info, - sizeof(arg64.LUN_info)); - err |= copy_from_user(&arg64.Request, &arg32->Request, - sizeof(arg64.Request)); - err |= copy_from_user(&arg64.error_info, &arg32->error_info, - sizeof(arg64.error_info)); - err |= get_user(arg64.buf_size, &arg32->buf_size); - err |= get_user(arg64.malloc_size, &arg32->malloc_size); - err |= get_user(cp, &arg32->buf); - arg64.buf = compat_ptr(cp); - err |= copy_to_user(p, &arg64, sizeof(arg64)); - - if (err) + if (copy_from_user(&arg64, arg32, + offsetof(BIG_IOCTL32_Command_struct, buf))) return -EFAULT; + if (get_user(cp, &arg32->buf)) + return -EFAULT; + arg64.buf = compat_ptr(cp); - err = hpsa_ioctl(dev, CCISS_BIG_PASSTHRU, p); + if (atomic_dec_if_positive(&h->passthru_cmds_avail) < 0) + return -EAGAIN; + err = hpsa_big_passthru_ioctl(h, &arg64); + atomic_inc(&h->passthru_cmds_avail); if (err) return err; - err |= copy_in_user(&arg32->error_info, &p->error_info, - sizeof(arg32->error_info)); - if (err) + if (copy_to_user(&arg32->error_info, &arg64.error_info, + sizeof(arg32->error_info))) return -EFAULT; - return err; + return 0; } static int hpsa_compat_ioctl(struct scsi_device *dev, unsigned int cmd, -- cgit v1.2.3-59-g8ed1b