projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 6179048a GKH |
1 | From 1129d270cbfbb7e2b1ec3dede4a13930bdd10e41 Mon Sep 17 00:00:00 2001 |
| 2 | From: Mateusz Berezecki <mateuszb@fastmail.fm> | |
| 3 | Date: Wed, 21 Dec 2016 09:19:14 -0800 | |
| 4 | Subject: USB: Increase usbfs transfer limit | |
| 5 | ||
| 6 | From: Mateusz Berezecki <mateuszb@fastmail.fm> | |
| 7 | ||
| 8 | commit 1129d270cbfbb7e2b1ec3dede4a13930bdd10e41 upstream. | |
| 9 | ||
| 10 | Promote a variable keeping track of USB transfer memory usage to a | |
| 11 | wider data type and allow for higher bandwidth transfers from a large | |
| 12 | number of USB devices connected to a single host. | |
| 13 | ||
| 14 | Signed-off-by: Mateusz Berezecki <mateuszb@fastmail.fm> | |
| 15 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 16 | ||
| 17 | --- | |
| 18 | drivers/usb/core/devio.c | 43 ++++++++++++++++--------------------------- | |
| 19 | 1 file changed, 16 insertions(+), 27 deletions(-) | |
| 20 | ||
| 21 | --- a/drivers/usb/core/devio.c | |
| 22 | +++ b/drivers/usb/core/devio.c | |
| 23 | @@ -134,42 +134,35 @@ enum snoop_when { | |
| 24 | #define USB_DEVICE_DEV MKDEV(USB_DEVICE_MAJOR, 0) | |
| 25 | ||
| 26 | /* Limit on the total amount of memory we can allocate for transfers */ | |
| 27 | -static unsigned usbfs_memory_mb = 16; | |
| 28 | +static u32 usbfs_memory_mb = 16; | |
| 29 | module_param(usbfs_memory_mb, uint, 0644); | |
| 30 | MODULE_PARM_DESC(usbfs_memory_mb, | |
| 31 | "maximum MB allowed for usbfs buffers (0 = no limit)"); | |
| 32 | ||
| 33 | -/* Hard limit, necessary to avoid arithmetic overflow */ | |
| 34 | -#define USBFS_XFER_MAX (UINT_MAX / 2 - 1000000) | |
| 35 | - | |
| 36 | -static atomic_t usbfs_memory_usage; /* Total memory currently allocated */ | |
| 37 | +static atomic64_t usbfs_memory_usage; /* Total memory currently allocated */ | |
| 38 | ||
| 39 | /* Check whether it's okay to allocate more memory for a transfer */ | |
| 40 | -static int usbfs_increase_memory_usage(unsigned amount) | |
| 41 | +static int usbfs_increase_memory_usage(u64 amount) | |
| 42 | { | |
| 43 | - unsigned lim; | |
| 44 | + u64 lim; | |
| 45 | ||
| 46 | - /* | |
| 47 | - * Convert usbfs_memory_mb to bytes, avoiding overflows. | |
| 48 | - * 0 means use the hard limit (effectively unlimited). | |
| 49 | - */ | |
| 50 | lim = ACCESS_ONCE(usbfs_memory_mb); | |
| 51 | - if (lim == 0 || lim > (USBFS_XFER_MAX >> 20)) | |
| 52 | - lim = USBFS_XFER_MAX; | |
| 53 | - else | |
| 54 | - lim <<= 20; | |
| 55 | + lim <<= 20; | |
| 56 | ||
| 57 | - atomic_add(amount, &usbfs_memory_usage); | |
| 58 | - if (atomic_read(&usbfs_memory_usage) <= lim) | |
| 59 | - return 0; | |
| 60 | - atomic_sub(amount, &usbfs_memory_usage); | |
| 61 | - return -ENOMEM; | |
| 62 | + atomic64_add(amount, &usbfs_memory_usage); | |
| 63 | + | |
| 64 | + if (lim > 0 && atomic64_read(&usbfs_memory_usage) > lim) { | |
| 65 | + atomic64_sub(amount, &usbfs_memory_usage); | |
| 66 | + return -ENOMEM; | |
| 67 | + } | |
| 68 | + | |
| 69 | + return 0; | |
| 70 | } | |
| 71 | ||
| 72 | /* Memory for a transfer is being deallocated */ | |
| 73 | -static void usbfs_decrease_memory_usage(unsigned amount) | |
| 74 | +static void usbfs_decrease_memory_usage(u64 amount) | |
| 75 | { | |
| 76 | - atomic_sub(amount, &usbfs_memory_usage); | |
| 77 | + atomic64_sub(amount, &usbfs_memory_usage); | |
| 78 | } | |
| 79 | ||
| 80 | static int connected(struct usb_dev_state *ps) | |
| 81 | @@ -1191,7 +1184,7 @@ static int proc_bulk(struct usb_dev_stat | |
| 82 | if (!usb_maxpacket(dev, pipe, !(bulk.ep & USB_DIR_IN))) | |
| 83 | return -EINVAL; | |
| 84 | len1 = bulk.len; | |
| 85 | - if (len1 >= USBFS_XFER_MAX) | |
| 86 | + if (len1 >= (INT_MAX - sizeof(struct urb))) | |
| 87 | return -EINVAL; | |
| 88 | ret = usbfs_increase_memory_usage(len1 + sizeof(struct urb)); | |
| 89 | if (ret) | |
| 90 | @@ -1584,10 +1577,6 @@ static int proc_do_submiturb(struct usb_ | |
| 91 | return -EINVAL; | |
| 92 | } | |
| 93 | ||
| 94 | - if (uurb->buffer_length >= USBFS_XFER_MAX) { | |
| 95 | - ret = -EINVAL; | |
| 96 | - goto error; | |
| 97 | - } | |
| 98 | if (uurb->buffer_length > 0 && | |
| 99 | !access_ok(is_in ? VERIFY_WRITE : VERIFY_READ, | |
| 100 | uurb->buffer, uurb->buffer_length)) { |