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-rw-r--r--drivers/atm/zatm.c4
-rw-r--r--drivers/hid/hid-debug.c8
-rw-r--r--drivers/hid/i2c-hid/i2c-hid.c2
-rw-r--r--drivers/md/dm-bufio.c15
-rw-r--r--drivers/media/i2c/cx25840/cx25840-core.c28
-rw-r--r--drivers/mtd/chips/cfi_cmdset_0002.c30
-rw-r--r--drivers/mtd/nand/mxc_nand.c5
-rw-r--r--drivers/mtd/ubi/eba.c92
-rw-r--r--drivers/net/ethernet/natsemi/sonic.c2
-rw-r--r--drivers/net/usb/qmi_wwan.c1
-rw-r--r--drivers/scsi/sg.c42
-rw-r--r--drivers/tty/n_tty.c13
12 files changed, 211 insertions, 31 deletions
diff --git a/drivers/atm/zatm.c b/drivers/atm/zatm.c
index 969c3c29000c..9b8130946a35 100644
--- a/drivers/atm/zatm.c
+++ b/drivers/atm/zatm.c
@@ -1148,8 +1148,8 @@ static void eprom_get_byte(struct zatm_dev *zatm_dev, unsigned char *byte,
}
-static unsigned char eprom_try_esi(struct atm_dev *dev, unsigned short cmd,
- int offset, int swap)
+static int eprom_try_esi(struct atm_dev *dev, unsigned short cmd, int offset,
+ int swap)
{
unsigned char buf[ZEPROM_SIZE];
struct zatm_dev *zatm_dev;
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 8bf61d295ffd..7192fa1d2786 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -1150,6 +1150,8 @@ copy_rest:
goto out;
if (list->tail > list->head) {
len = list->tail - list->head;
+ if (len > count)
+ len = count;
if (copy_to_user(buffer + ret, &list->hid_debug_buf[list->head], len)) {
ret = -EFAULT;
@@ -1159,6 +1161,8 @@ copy_rest:
list->head += len;
} else {
len = HID_DEBUG_BUFSIZE - list->head;
+ if (len > count)
+ len = count;
if (copy_to_user(buffer, &list->hid_debug_buf[list->head], len)) {
ret = -EFAULT;
@@ -1166,7 +1170,9 @@ copy_rest:
}
list->head = 0;
ret += len;
- goto copy_rest;
+ count -= len;
+ if (count > 0)
+ goto copy_rest;
}
}
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 7f2c1c35cf55..2d86ac02b2cd 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -399,7 +399,7 @@ static void i2c_hid_get_input(struct i2c_hid *ihid)
return;
}
- if ((ret_size > size) || (ret_size <= 2)) {
+ if ((ret_size > size) || (ret_size < 2)) {
dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
__func__, size, ret_size);
return;
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index a673f0e7a9a7..1cf56302edcd 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -761,12 +761,14 @@ enum new_flag {
static struct dm_buffer *__alloc_buffer_wait_no_callback(struct dm_bufio_client *c, enum new_flag nf)
{
struct dm_buffer *b;
+ bool tried_noio_alloc = false;
/*
* dm-bufio is resistant to allocation failures (it just keeps
* one buffer reserved in cases all the allocations fail).
* So set flags to not try too hard:
- * GFP_NOIO: don't recurse into the I/O layer
+ * GFP_NOWAIT: don't wait; if we need to sleep we'll release our
+ * mutex and wait ourselves.
* __GFP_NORETRY: don't retry and rather return failure
* __GFP_NOMEMALLOC: don't use emergency reserves
* __GFP_NOWARN: don't print a warning in case of failure
@@ -776,7 +778,7 @@ static struct dm_buffer *__alloc_buffer_wait_no_callback(struct dm_bufio_client
*/
while (1) {
if (dm_bufio_cache_size_latch != 1) {
- b = alloc_buffer(c, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
+ b = alloc_buffer(c, GFP_NOWAIT | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
if (b)
return b;
}
@@ -784,6 +786,15 @@ static struct dm_buffer *__alloc_buffer_wait_no_callback(struct dm_bufio_client
if (nf == NF_PREFETCH)
return NULL;
+ if (dm_bufio_cache_size_latch != 1 && !tried_noio_alloc) {
+ dm_bufio_unlock(c);
+ b = alloc_buffer(c, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
+ dm_bufio_lock(c);
+ if (b)
+ return b;
+ tried_noio_alloc = true;
+ }
+
if (!list_empty(&c->reserved_buffers)) {
b = list_entry(c->reserved_buffers.next,
struct dm_buffer, lru_list);
diff --git a/drivers/media/i2c/cx25840/cx25840-core.c b/drivers/media/i2c/cx25840/cx25840-core.c
index 50255128ec33..d96582b684c4 100644
--- a/drivers/media/i2c/cx25840/cx25840-core.c
+++ b/drivers/media/i2c/cx25840/cx25840-core.c
@@ -467,8 +467,13 @@ static void cx23885_initialize(struct i2c_client *client)
{
DEFINE_WAIT(wait);
struct cx25840_state *state = to_state(i2c_get_clientdata(client));
+ u32 clk_freq = 0;
struct workqueue_struct *q;
+ /* cx23885 sets hostdata to clk_freq pointer */
+ if (v4l2_get_subdev_hostdata(&state->sd))
+ clk_freq = *((u32 *)v4l2_get_subdev_hostdata(&state->sd));
+
/*
* Come out of digital power down
* The CX23888, at least, needs this, otherwise registers aside from
@@ -504,8 +509,13 @@ static void cx23885_initialize(struct i2c_client *client)
* 50.0 MHz * (0xb + 0xe8ba26/0x2000000)/4 = 5 * 28.636363 MHz
* 572.73 MHz before post divide
*/
- /* HVR1850 or 50MHz xtal */
- cx25840_write(client, 0x2, 0x71);
+ if (clk_freq == 25000000) {
+ /* 888/ImpactVCBe or 25Mhz xtal */
+ ; /* nothing to do */
+ } else {
+ /* HVR1850 or 50MHz xtal */
+ cx25840_write(client, 0x2, 0x71);
+ }
cx25840_write4(client, 0x11c, 0x01d1744c);
cx25840_write4(client, 0x118, 0x00000416);
cx25840_write4(client, 0x404, 0x0010253e);
@@ -548,9 +558,15 @@ static void cx23885_initialize(struct i2c_client *client)
/* HVR1850 */
switch (state->id) {
case CX23888_AV:
- /* 888/HVR1250 specific */
- cx25840_write4(client, 0x10c, 0x13333333);
- cx25840_write4(client, 0x108, 0x00000515);
+ if (clk_freq == 25000000) {
+ /* 888/ImpactVCBe or 25MHz xtal */
+ cx25840_write4(client, 0x10c, 0x01b6db7b);
+ cx25840_write4(client, 0x108, 0x00000512);
+ } else {
+ /* 888/HVR1250 or 50MHz xtal */
+ cx25840_write4(client, 0x10c, 0x13333333);
+ cx25840_write4(client, 0x108, 0x00000515);
+ }
break;
default:
cx25840_write4(client, 0x10c, 0x002be2c9);
@@ -577,7 +593,7 @@ static void cx23885_initialize(struct i2c_client *client)
* 368.64 MHz before post divide
* 122.88 MHz / 0xa = 12.288 MHz
*/
- /* HVR1850 or 50MHz xtal */
+ /* HVR1850 or 50MHz xtal or 25MHz xtal */
cx25840_write4(client, 0x114, 0x017dbf48);
cx25840_write4(client, 0x110, 0x000a030e);
break;
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 7eb3155fa3c0..529115b219b6 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -42,7 +42,7 @@
#define AMD_BOOTLOC_BUG
#define FORCE_WORD_WRITE 0
-#define MAX_WORD_RETRIES 3
+#define MAX_RETRIES 3
#define SST49LF004B 0x0060
#define SST49LF040B 0x0050
@@ -1645,7 +1645,7 @@ static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
- if (++retry_cnt <= MAX_WORD_RETRIES)
+ if (++retry_cnt <= MAX_RETRIES)
goto retry;
ret = -EIO;
@@ -2104,7 +2104,7 @@ retry:
map_write(map, CMD(0xF0), chip->start);
/* FIXME - should have reset delay before continuing */
- if (++retry_cnt <= MAX_WORD_RETRIES)
+ if (++retry_cnt <= MAX_RETRIES)
goto retry;
ret = -EIO;
@@ -2239,6 +2239,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
unsigned long int adr;
DECLARE_WAITQUEUE(wait, current);
int ret = 0;
+ int retry_cnt = 0;
adr = cfi->addr_unlock1;
@@ -2256,6 +2257,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
ENABLE_VPP(map);
xip_disable(map, chip, adr);
+ retry:
cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
@@ -2292,12 +2294,13 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
chip->erase_suspended = 0;
}
- if (chip_ready(map, adr))
+ if (chip_good(map, adr, map_word_ff(map)))
break;
if (time_after(jiffies, timeo)) {
printk(KERN_WARNING "MTD %s(): software timeout\n",
__func__ );
+ ret = -EIO;
break;
}
@@ -2305,12 +2308,15 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
UDELAY(map, chip, adr, 1000000/HZ);
}
/* Did we succeed? */
- if (!chip_good(map, adr, map_word_ff(map))) {
+ if (ret) {
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
- ret = -EIO;
+ if (++retry_cnt <= MAX_RETRIES) {
+ ret = 0;
+ goto retry;
+ }
}
chip->state = FL_READY;
@@ -2329,6 +2335,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
unsigned long timeo = jiffies + HZ;
DECLARE_WAITQUEUE(wait, current);
int ret = 0;
+ int retry_cnt = 0;
adr += chip->start;
@@ -2346,6 +2353,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
ENABLE_VPP(map);
xip_disable(map, chip, adr);
+ retry:
cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
@@ -2382,7 +2390,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
chip->erase_suspended = 0;
}
- if (chip_ready(map, adr)) {
+ if (chip_good(map, adr, map_word_ff(map))) {
xip_enable(map, chip, adr);
break;
}
@@ -2391,6 +2399,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
xip_enable(map, chip, adr);
printk(KERN_WARNING "MTD %s(): software timeout\n",
__func__ );
+ ret = -EIO;
break;
}
@@ -2398,12 +2407,15 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
UDELAY(map, chip, adr, 1000000/HZ);
}
/* Did we succeed? */
- if (!chip_good(map, adr, map_word_ff(map))) {
+ if (ret) {
/* reset on all failures. */
map_write( map, CMD(0xF0), chip->start );
/* FIXME - should have reset delay before continuing */
- ret = -EIO;
+ if (++retry_cnt <= MAX_RETRIES) {
+ ret = 0;
+ goto retry;
+ }
}
chip->state = FL_READY;
diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c
index dba262bf766f..7cf0473c79e8 100644
--- a/drivers/mtd/nand/mxc_nand.c
+++ b/drivers/mtd/nand/mxc_nand.c
@@ -49,7 +49,7 @@
#define NFC_V1_V2_CONFIG (host->regs + 0x0a)
#define NFC_V1_V2_ECC_STATUS_RESULT (host->regs + 0x0c)
#define NFC_V1_V2_RSLTMAIN_AREA (host->regs + 0x0e)
-#define NFC_V1_V2_RSLTSPARE_AREA (host->regs + 0x10)
+#define NFC_V21_RSLTSPARE_AREA (host->regs + 0x10)
#define NFC_V1_V2_WRPROT (host->regs + 0x12)
#define NFC_V1_UNLOCKSTART_BLKADDR (host->regs + 0x14)
#define NFC_V1_UNLOCKEND_BLKADDR (host->regs + 0x16)
@@ -958,6 +958,9 @@ static void preset_v2(struct mtd_info *mtd)
writew(config1, NFC_V1_V2_CONFIG1);
/* preset operation */
+ /* spare area size in 16-bit half-words */
+ writew(mtd->oobsize / 2, NFC_V21_RSLTSPARE_AREA);
+
/* Unlock the internal RAM Buffer */
writew(0x2, NFC_V1_V2_CONFIG);
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 65b35e0a1272..9c763e14e2d6 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -350,6 +350,82 @@ out_unlock:
return err;
}
+#ifdef CONFIG_MTD_UBI_FASTMAP
+/**
+ * check_mapping - check and fixup a mapping
+ * @ubi: UBI device description object
+ * @vol: volume description object
+ * @lnum: logical eraseblock number
+ * @pnum: physical eraseblock number
+ *
+ * Checks whether a given mapping is valid. Fastmap cannot track LEB unmap
+ * operations, if such an operation is interrupted the mapping still looks
+ * good, but upon first read an ECC is reported to the upper layer.
+ * Normaly during the full-scan at attach time this is fixed, for Fastmap
+ * we have to deal with it while reading.
+ * If the PEB behind a LEB shows this symthom we change the mapping to
+ * %UBI_LEB_UNMAPPED and schedule the PEB for erasure.
+ *
+ * Returns 0 on success, negative error code in case of failure.
+ */
+static int check_mapping(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
+ int *pnum)
+{
+ int err;
+ struct ubi_vid_hdr *vid_hdr;
+
+ if (!ubi->fast_attach)
+ return 0;
+
+ vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
+ if (!vid_hdr)
+ return -ENOMEM;
+
+ err = ubi_io_read_vid_hdr(ubi, *pnum, vid_hdr, 0);
+ if (err > 0 && err != UBI_IO_BITFLIPS) {
+ int torture = 0;
+
+ switch (err) {
+ case UBI_IO_FF:
+ case UBI_IO_FF_BITFLIPS:
+ case UBI_IO_BAD_HDR:
+ case UBI_IO_BAD_HDR_EBADMSG:
+ break;
+ default:
+ ubi_assert(0);
+ }
+
+ if (err == UBI_IO_BAD_HDR_EBADMSG || err == UBI_IO_FF_BITFLIPS)
+ torture = 1;
+
+ down_read(&ubi->fm_sem);
+ vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED;
+ up_read(&ubi->fm_sem);
+ ubi_wl_put_peb(ubi, vol->vol_id, lnum, *pnum, torture);
+
+ *pnum = UBI_LEB_UNMAPPED;
+ } else if (err < 0) {
+ ubi_err("unable to read VID header back from PEB %i: %i",
+ *pnum, err);
+
+ goto out_free;
+ }
+
+ err = 0;
+
+out_free:
+ ubi_free_vid_hdr(ubi, vid_hdr);
+
+ return err;
+}
+#else
+static int check_mapping(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
+ int *pnum)
+{
+ return 0;
+}
+#endif
+
/**
* ubi_eba_read_leb - read data.
* @ubi: UBI device description object
@@ -381,7 +457,13 @@ int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
return err;
pnum = vol->eba_tbl[lnum];
- if (pnum < 0) {
+ if (pnum >= 0) {
+ err = check_mapping(ubi, vol, lnum, &pnum);
+ if (err < 0)
+ goto out_unlock;
+ }
+
+ if (pnum == UBI_LEB_UNMAPPED) {
/*
* The logical eraseblock is not mapped, fill the whole buffer
* with 0xFF bytes. The exception is static volumes for which
@@ -689,6 +771,14 @@ int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
pnum = vol->eba_tbl[lnum];
if (pnum >= 0) {
+ err = check_mapping(ubi, vol, lnum, &pnum);
+ if (err < 0) {
+ leb_write_unlock(ubi, vol_id, lnum);
+ return err;
+ }
+ }
+
+ if (pnum >= 0) {
dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d",
len, offset, vol_id, lnum, pnum);
diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c
index 1bd419dbda6d..0798b4adb039 100644
--- a/drivers/net/ethernet/natsemi/sonic.c
+++ b/drivers/net/ethernet/natsemi/sonic.c
@@ -71,7 +71,7 @@ static int sonic_open(struct net_device *dev)
for (i = 0; i < SONIC_NUM_RRS; i++) {
dma_addr_t laddr = dma_map_single(lp->device, skb_put(lp->rx_skb[i], SONIC_RBSIZE),
SONIC_RBSIZE, DMA_FROM_DEVICE);
- if (!laddr) {
+ if (dma_mapping_error(lp->device, laddr)) {
while(i > 0) { /* free any that were mapped successfully */
i--;
dma_unmap_single(lp->device, lp->rx_laddr[i], SONIC_RBSIZE, DMA_FROM_DEVICE);
diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index 1a13ff39cb28..3868e6d1d653 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -677,6 +677,7 @@ static const struct usb_device_id products[] = {
{QMI_FIXED_INTF(0x05c6, 0x920d, 0)},
{QMI_FIXED_INTF(0x05c6, 0x920d, 5)},
{QMI_FIXED_INTF(0x0846, 0x68a2, 8)},
+ {QMI_FIXED_INTF(0x0846, 0x68d3, 8)}, /* Netgear Aircard 779S */
{QMI_FIXED_INTF(0x12d1, 0x140c, 1)}, /* Huawei E173 */
{QMI_FIXED_INTF(0x12d1, 0x14ac, 1)}, /* Huawei E1820 */
{QMI_FIXED_INTF(0x1435, 0xd181, 3)}, /* Wistron NeWeb D18Q1 */
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 7537b8188ce5..8ae1d31a7337 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -52,6 +52,7 @@ static int sg_version_num = 30536; /* 2 digits for each component */
#include <linux/atomic.h>
#include <linux/ratelimit.h>
#include <linux/sizes.h>
+#include <linux/cred.h> /* for sg_check_file_access() */
#include "scsi.h"
#include <scsi/scsi_dbg.h>
@@ -222,6 +223,33 @@ static void sg_device_destroy(struct kref *kref);
sdev_printk(prefix, (sdp)->device, "[%s] " fmt, \
(sdp)->disk->disk_name, ##a)
+/*
+ * The SCSI interfaces that use read() and write() as an asynchronous variant of
+ * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways
+ * to trigger read() and write() calls from various contexts with elevated
+ * privileges. This can lead to kernel memory corruption (e.g. if these
+ * interfaces are called through splice()) and privilege escalation inside
+ * userspace (e.g. if a process with access to such a device passes a file
+ * descriptor to a SUID binary as stdin/stdout/stderr).
+ *
+ * This function provides protection for the legacy API by restricting the
+ * calling context.
+ */
+static int sg_check_file_access(struct file *filp, const char *caller)
+{
+ if (filp->f_cred != current_real_cred()) {
+ pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
+ caller, task_tgid_vnr(current), current->comm);
+ return -EPERM;
+ }
+ if (unlikely(segment_eq(get_fs(), KERNEL_DS))) {
+ pr_err_once("%s: process %d (%s) called from kernel context, this is not allowed.\n",
+ caller, task_tgid_vnr(current), current->comm);
+ return -EACCES;
+ }
+ return 0;
+}
+
static int sg_allow_access(struct file *filp, unsigned char *cmd)
{
struct sg_fd *sfp = filp->private_data;
@@ -406,6 +434,14 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
struct sg_header *old_hdr = NULL;
int retval = 0;
+ /*
+ * This could cause a response to be stranded. Close the associated
+ * file descriptor to free up any resources being held.
+ */
+ retval = sg_check_file_access(filp, __func__);
+ if (retval)
+ return retval;
+
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
@@ -593,9 +629,11 @@ sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
struct sg_header old_hdr;
sg_io_hdr_t *hp;
unsigned char cmnd[SG_MAX_CDB_SIZE];
+ int retval;
- if (unlikely(segment_eq(get_fs(), KERNEL_DS)))
- return -EINVAL;
+ retval = sg_check_file_access(filp, __func__);
+ if (retval)
+ return retval;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 196285b7cab6..a896159dca60 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -128,6 +128,8 @@ struct n_tty_data {
struct mutex output_lock;
};
+#define MASK(x) ((x) & (N_TTY_BUF_SIZE - 1))
+
static inline size_t read_cnt(struct n_tty_data *ldata)
{
return ldata->read_head - ldata->read_tail;
@@ -1028,14 +1030,15 @@ static void eraser(unsigned char c, struct tty_struct *tty)
}
seen_alnums = 0;
- while (ldata->read_head != ldata->canon_head) {
+ while (MASK(ldata->read_head) != MASK(ldata->canon_head)) {
head = ldata->read_head;
/* erase a single possibly multibyte character */
do {
head--;
c = read_buf(ldata, head);
- } while (is_continuation(c, tty) && head != ldata->canon_head);
+ } while (is_continuation(c, tty) &&
+ MASK(head) != MASK(ldata->canon_head));
/* do not partially erase */
if (is_continuation(c, tty))
@@ -1077,7 +1080,7 @@ static void eraser(unsigned char c, struct tty_struct *tty)
* This info is used to go back the correct
* number of columns.
*/
- while (tail != ldata->canon_head) {
+ while (MASK(tail) != MASK(ldata->canon_head)) {
tail--;
c = read_buf(ldata, tail);
if (c == '\t') {
@@ -1334,7 +1337,7 @@ n_tty_receive_char_special(struct tty_struct *tty, unsigned char c)
finish_erasing(ldata);
echo_char(c, tty);
echo_char_raw('\n', ldata);
- while (tail != ldata->read_head) {
+ while (MASK(tail) != MASK(ldata->read_head)) {
echo_char(read_buf(ldata, tail), tty);
tail++;
}
@@ -2503,7 +2506,7 @@ static unsigned long inq_canon(struct n_tty_data *ldata)
tail = ldata->read_tail;
nr = head - tail;
/* Skip EOF-chars.. */
- while (head != tail) {
+ while (MASK(head) != MASK(tail)) {
if (test_bit(tail & (N_TTY_BUF_SIZE - 1), ldata->read_flags) &&
read_buf(ldata, tail) == __DISABLED_CHAR)
nr--;