From d794a02111cd3393da69bc7d6dd2b6074bd037cc Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Sun, 28 Jun 2009 23:34:14 +0200 Subject: USB: fix memleak in usbfs This patch fixes a memory leak in devio.c::processcompl If writing to user space fails the packet must be discarded, as it already has been removed from the queue of completed packets. Signed-off-by: Oliver Neukum Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'drivers/usb/core/devio.c') diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 308609039c73..706f18156af8 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -1231,22 +1231,22 @@ static int processcompl(struct async *as, void __user * __user *arg) if (as->userbuffer) if (copy_to_user(as->userbuffer, urb->transfer_buffer, urb->transfer_buffer_length)) - return -EFAULT; + goto err_out; if (put_user(as->status, &userurb->status)) - return -EFAULT; + goto err_out; if (put_user(urb->actual_length, &userurb->actual_length)) - return -EFAULT; + goto err_out; if (put_user(urb->error_count, &userurb->error_count)) - return -EFAULT; + goto err_out; if (usb_endpoint_xfer_isoc(&urb->ep->desc)) { for (i = 0; i < urb->number_of_packets; i++) { if (put_user(urb->iso_frame_desc[i].actual_length, &userurb->iso_frame_desc[i].actual_length)) - return -EFAULT; + goto err_out; if (put_user(urb->iso_frame_desc[i].status, &userurb->iso_frame_desc[i].status)) - return -EFAULT; + goto err_out; } } @@ -1255,6 +1255,10 @@ static int processcompl(struct async *as, void __user * __user *arg) if (put_user(addr, (void __user * __user *)arg)) return -EFAULT; return 0; + +err_out: + free_async(as); + return -EFAULT; } static struct async *reap_as(struct dev_state *ps) -- cgit v1.2.3 From 516a1a07f0219d6672fb6b8e49fb9d5d533c2e89 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Wed, 8 Jul 2009 19:09:23 +0200 Subject: USB: fix race leading to a write after kfree in usbfs this fixes a race between async_completed() and proc_reapurbnonblock(). CPU A CPU B spin_lock(&ps->lock); list_move_tail(&as->asynclist, &ps->async_completed); spin_unlock(&ps->lock); if (!(as = async_getcompleted(ps))) return -EAGAIN; return processcompl(as, (void __user * __user *)arg); processcompl() calls free_async() which calls kfree(as) as->status = urb->status; if (as->signr) { sinfo.si_signo = as->signr; sinfo.si_errno = as->status; sinfo.si_code = SI_ASYNCIO; sinfo.si_addr = as->userurb; kill_pid_info_as_uid(as->signr, &sinfo, as->pid, as->uid, as->euid, as->secid); } snoop(&urb->dev->dev, "urb complete\n"); snoop_urb(urb, as->userurb); write after kfree Signed-off-by: Oliver Neukum --- drivers/usb/core/devio.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'drivers/usb/core/devio.c') diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 706f18156af8..46ca2af5ef1c 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -325,21 +325,34 @@ static void async_completed(struct urb *urb) struct async *as = urb->context; struct dev_state *ps = as->ps; struct siginfo sinfo; + struct pid *pid = NULL; + uid_t uid = 0; + uid_t euid = 0; + u32 secid = 0; + int signr; spin_lock(&ps->lock); list_move_tail(&as->asynclist, &ps->async_completed); - spin_unlock(&ps->lock); as->status = urb->status; - if (as->signr) { + signr = as->signr; + if (signr) { sinfo.si_signo = as->signr; sinfo.si_errno = as->status; sinfo.si_code = SI_ASYNCIO; sinfo.si_addr = as->userurb; - kill_pid_info_as_uid(as->signr, &sinfo, as->pid, as->uid, - as->euid, as->secid); + pid = as->pid; + uid = as->uid; + euid = as->euid; + secid = as->secid; } snoop(&urb->dev->dev, "urb complete\n"); snoop_urb(urb, as->userurb); + spin_unlock(&ps->lock); + + if (signr) + kill_pid_info_as_uid(sinfo.si_signo, &sinfo, pid, uid, + euid, secid); + wake_up(&ps->wait); } -- cgit v1.2.3 From 9180135bc80ab11199d482b6111e23f74d65af4a Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Mon, 29 Jun 2009 11:04:54 -0400 Subject: USB: handle zero-length usbfs submissions correctly This patch (as1262) fixes a bug in usbfs: It refuses to accept zero-length transfers, and it insists that the buffer pointer be valid even if there is no data being transferred. The patch also consolidates a bunch of repetitive access_ok() checks into a single check, which incidentally fixes the lack of such a check for Isochronous URBs. Signed-off-by: Alan Stern Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 41 ++++++++++++++++++++--------------------- 1 file changed, 20 insertions(+), 21 deletions(-) (limited to 'drivers/usb/core/devio.c') diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 46ca2af5ef1c..38b8bce782d6 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -995,7 +995,7 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, USBDEVFS_URB_ZERO_PACKET | USBDEVFS_URB_NO_INTERRUPT)) return -EINVAL; - if (!uurb->buffer) + if (uurb->buffer_length > 0 && !uurb->buffer) return -EINVAL; if (!(uurb->type == USBDEVFS_URB_TYPE_CONTROL && (uurb->endpoint & ~USB_ENDPOINT_DIR_MASK) == 0)) { @@ -1051,11 +1051,6 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, is_in = 0; uurb->endpoint &= ~USB_DIR_IN; } - if (!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ, - uurb->buffer, uurb->buffer_length)) { - kfree(dr); - return -EFAULT; - } snoop(&ps->dev->dev, "control urb: bRequest=%02x " "bRrequestType=%02x wValue=%04x " "wIndex=%04x wLength=%04x\n", @@ -1075,9 +1070,6 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, uurb->number_of_packets = 0; if (uurb->buffer_length > MAX_USBFS_BUFFER_SIZE) return -EINVAL; - if (!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ, - uurb->buffer, uurb->buffer_length)) - return -EFAULT; snoop(&ps->dev->dev, "bulk urb\n"); break; @@ -1119,28 +1111,35 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, return -EINVAL; if (uurb->buffer_length > MAX_USBFS_BUFFER_SIZE) return -EINVAL; - if (!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ, - uurb->buffer, uurb->buffer_length)) - return -EFAULT; snoop(&ps->dev->dev, "interrupt urb\n"); break; default: return -EINVAL; } - as = alloc_async(uurb->number_of_packets); - if (!as) { + if (uurb->buffer_length > 0 && + !access_ok(is_in ? VERIFY_WRITE : VERIFY_READ, + uurb->buffer, uurb->buffer_length)) { kfree(isopkt); kfree(dr); - return -ENOMEM; + return -EFAULT; } - as->urb->transfer_buffer = kmalloc(uurb->buffer_length, GFP_KERNEL); - if (!as->urb->transfer_buffer) { + as = alloc_async(uurb->number_of_packets); + if (!as) { kfree(isopkt); kfree(dr); - free_async(as); return -ENOMEM; } + if (uurb->buffer_length > 0) { + as->urb->transfer_buffer = kmalloc(uurb->buffer_length, + GFP_KERNEL); + if (!as->urb->transfer_buffer) { + kfree(isopkt); + kfree(dr); + free_async(as); + return -ENOMEM; + } + } as->urb->dev = ps->dev; as->urb->pipe = (uurb->type << 30) | __create_pipe(ps->dev, uurb->endpoint & 0xf) | @@ -1182,7 +1181,7 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, kfree(isopkt); as->ps = ps; as->userurb = arg; - if (uurb->endpoint & USB_DIR_IN) + if (is_in && uurb->buffer_length > 0) as->userbuffer = uurb->buffer; else as->userbuffer = NULL; @@ -1192,9 +1191,9 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb, as->uid = cred->uid; as->euid = cred->euid; security_task_getsecid(current, &as->secid); - if (!is_in) { + if (!is_in && uurb->buffer_length > 0) { if (copy_from_user(as->urb->transfer_buffer, uurb->buffer, - as->urb->transfer_buffer_length)) { + uurb->buffer_length)) { free_async(as); return -EFAULT; } -- cgit v1.2.3