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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /fs/ntfs3/lznt.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'fs/ntfs3/lznt.c')
-rw-r--r--fs/ntfs3/lznt.c453
1 files changed, 453 insertions, 0 deletions
diff --git a/fs/ntfs3/lznt.c b/fs/ntfs3/lznt.c
new file mode 100644
index 000000000..28f654561
--- /dev/null
+++ b/fs/ntfs3/lznt.c
@@ -0,0 +1,453 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *
+ * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include "debug.h"
+#include "ntfs_fs.h"
+
+// clang-format off
+/* Src buffer is zero. */
+#define LZNT_ERROR_ALL_ZEROS 1
+#define LZNT_CHUNK_SIZE 0x1000
+// clang-format on
+
+struct lznt_hash {
+ const u8 *p1;
+ const u8 *p2;
+};
+
+struct lznt {
+ const u8 *unc;
+ const u8 *unc_end;
+ const u8 *best_match;
+ size_t max_len;
+ bool std;
+
+ struct lznt_hash hash[LZNT_CHUNK_SIZE];
+};
+
+static inline size_t get_match_len(const u8 *ptr, const u8 *end, const u8 *prev,
+ size_t max_len)
+{
+ size_t len = 0;
+
+ while (ptr + len < end && ptr[len] == prev[len] && ++len < max_len)
+ ;
+ return len;
+}
+
+static size_t longest_match_std(const u8 *src, struct lznt *ctx)
+{
+ size_t hash_index;
+ size_t len1 = 0, len2 = 0;
+ const u8 **hash;
+
+ hash_index =
+ ((40543U * ((((src[0] << 4) ^ src[1]) << 4) ^ src[2])) >> 4) &
+ (LZNT_CHUNK_SIZE - 1);
+
+ hash = &(ctx->hash[hash_index].p1);
+
+ if (hash[0] >= ctx->unc && hash[0] < src && hash[0][0] == src[0] &&
+ hash[0][1] == src[1] && hash[0][2] == src[2]) {
+ len1 = 3;
+ if (ctx->max_len > 3)
+ len1 += get_match_len(src + 3, ctx->unc_end,
+ hash[0] + 3, ctx->max_len - 3);
+ }
+
+ if (hash[1] >= ctx->unc && hash[1] < src && hash[1][0] == src[0] &&
+ hash[1][1] == src[1] && hash[1][2] == src[2]) {
+ len2 = 3;
+ if (ctx->max_len > 3)
+ len2 += get_match_len(src + 3, ctx->unc_end,
+ hash[1] + 3, ctx->max_len - 3);
+ }
+
+ /* Compare two matches and select the best one. */
+ if (len1 < len2) {
+ ctx->best_match = hash[1];
+ len1 = len2;
+ } else {
+ ctx->best_match = hash[0];
+ }
+
+ hash[1] = hash[0];
+ hash[0] = src;
+ return len1;
+}
+
+static size_t longest_match_best(const u8 *src, struct lznt *ctx)
+{
+ size_t max_len;
+ const u8 *ptr;
+
+ if (ctx->unc >= src || !ctx->max_len)
+ return 0;
+
+ max_len = 0;
+ for (ptr = ctx->unc; ptr < src; ++ptr) {
+ size_t len =
+ get_match_len(src, ctx->unc_end, ptr, ctx->max_len);
+ if (len >= max_len) {
+ max_len = len;
+ ctx->best_match = ptr;
+ }
+ }
+
+ return max_len >= 3 ? max_len : 0;
+}
+
+static const size_t s_max_len[] = {
+ 0x1002, 0x802, 0x402, 0x202, 0x102, 0x82, 0x42, 0x22, 0x12,
+};
+
+static const size_t s_max_off[] = {
+ 0x10, 0x20, 0x40, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000,
+};
+
+static inline u16 make_pair(size_t offset, size_t len, size_t index)
+{
+ return ((offset - 1) << (12 - index)) |
+ ((len - 3) & (((1 << (12 - index)) - 1)));
+}
+
+static inline size_t parse_pair(u16 pair, size_t *offset, size_t index)
+{
+ *offset = 1 + (pair >> (12 - index));
+ return 3 + (pair & ((1 << (12 - index)) - 1));
+}
+
+/*
+ * compress_chunk
+ *
+ * Return:
+ * * 0 - Ok, @cmpr contains @cmpr_chunk_size bytes of compressed data.
+ * * 1 - Input buffer is full zero.
+ * * -2 - The compressed buffer is too small to hold the compressed data.
+ */
+static inline int compress_chunk(size_t (*match)(const u8 *, struct lznt *),
+ const u8 *unc, const u8 *unc_end, u8 *cmpr,
+ u8 *cmpr_end, size_t *cmpr_chunk_size,
+ struct lznt *ctx)
+{
+ size_t cnt = 0;
+ size_t idx = 0;
+ const u8 *up = unc;
+ u8 *cp = cmpr + 3;
+ u8 *cp2 = cmpr + 2;
+ u8 not_zero = 0;
+ /* Control byte of 8-bit values: ( 0 - means byte as is, 1 - short pair ). */
+ u8 ohdr = 0;
+ u8 *last;
+ u16 t16;
+
+ if (unc + LZNT_CHUNK_SIZE < unc_end)
+ unc_end = unc + LZNT_CHUNK_SIZE;
+
+ last = min(cmpr + LZNT_CHUNK_SIZE + sizeof(short), cmpr_end);
+
+ ctx->unc = unc;
+ ctx->unc_end = unc_end;
+ ctx->max_len = s_max_len[0];
+
+ while (up < unc_end) {
+ size_t max_len;
+
+ while (unc + s_max_off[idx] < up)
+ ctx->max_len = s_max_len[++idx];
+
+ /* Find match. */
+ max_len = up + 3 <= unc_end ? (*match)(up, ctx) : 0;
+
+ if (!max_len) {
+ if (cp >= last)
+ goto NotCompressed;
+ not_zero |= *cp++ = *up++;
+ } else if (cp + 1 >= last) {
+ goto NotCompressed;
+ } else {
+ t16 = make_pair(up - ctx->best_match, max_len, idx);
+ *cp++ = t16;
+ *cp++ = t16 >> 8;
+
+ ohdr |= 1 << cnt;
+ up += max_len;
+ }
+
+ cnt = (cnt + 1) & 7;
+ if (!cnt) {
+ *cp2 = ohdr;
+ ohdr = 0;
+ cp2 = cp;
+ cp += 1;
+ }
+ }
+
+ if (cp2 < last)
+ *cp2 = ohdr;
+ else
+ cp -= 1;
+
+ *cmpr_chunk_size = cp - cmpr;
+
+ t16 = (*cmpr_chunk_size - 3) | 0xB000;
+ cmpr[0] = t16;
+ cmpr[1] = t16 >> 8;
+
+ return not_zero ? 0 : LZNT_ERROR_ALL_ZEROS;
+
+NotCompressed:
+
+ if ((cmpr + LZNT_CHUNK_SIZE + sizeof(short)) > last)
+ return -2;
+
+ /*
+ * Copy non cmpr data.
+ * 0x3FFF == ((LZNT_CHUNK_SIZE + 2 - 3) | 0x3000)
+ */
+ cmpr[0] = 0xff;
+ cmpr[1] = 0x3f;
+
+ memcpy(cmpr + sizeof(short), unc, LZNT_CHUNK_SIZE);
+ *cmpr_chunk_size = LZNT_CHUNK_SIZE + sizeof(short);
+
+ return 0;
+}
+
+static inline ssize_t decompress_chunk(u8 *unc, u8 *unc_end, const u8 *cmpr,
+ const u8 *cmpr_end)
+{
+ u8 *up = unc;
+ u8 ch = *cmpr++;
+ size_t bit = 0;
+ size_t index = 0;
+ u16 pair;
+ size_t offset, length;
+
+ /* Do decompression until pointers are inside range. */
+ while (up < unc_end && cmpr < cmpr_end) {
+ /* Correct index */
+ while (unc + s_max_off[index] < up)
+ index += 1;
+
+ /* Check the current flag for zero. */
+ if (!(ch & (1 << bit))) {
+ /* Just copy byte. */
+ *up++ = *cmpr++;
+ goto next;
+ }
+
+ /* Check for boundary. */
+ if (cmpr + 1 >= cmpr_end)
+ return -EINVAL;
+
+ /* Read a short from little endian stream. */
+ pair = cmpr[1];
+ pair <<= 8;
+ pair |= cmpr[0];
+
+ cmpr += 2;
+
+ /* Translate packed information into offset and length. */
+ length = parse_pair(pair, &offset, index);
+
+ /* Check offset for boundary. */
+ if (unc + offset > up)
+ return -EINVAL;
+
+ /* Truncate the length if necessary. */
+ if (up + length >= unc_end)
+ length = unc_end - up;
+
+ /* Now we copy bytes. This is the heart of LZ algorithm. */
+ for (; length > 0; length--, up++)
+ *up = *(up - offset);
+
+next:
+ /* Advance flag bit value. */
+ bit = (bit + 1) & 7;
+
+ if (!bit) {
+ if (cmpr >= cmpr_end)
+ break;
+
+ ch = *cmpr++;
+ }
+ }
+
+ /* Return the size of uncompressed data. */
+ return up - unc;
+}
+
+/*
+ * get_lznt_ctx
+ * @level: 0 - Standard compression.
+ * !0 - Best compression, requires a lot of cpu.
+ */
+struct lznt *get_lznt_ctx(int level)
+{
+ struct lznt *r = kzalloc(level ? offsetof(struct lznt, hash)
+ : sizeof(struct lznt),
+ GFP_NOFS);
+
+ if (r)
+ r->std = !level;
+ return r;
+}
+
+/*
+ * compress_lznt - Compresses @unc into @cmpr
+ *
+ * Return:
+ * * +x - Ok, @cmpr contains 'final_compressed_size' bytes of compressed data.
+ * * 0 - Input buffer is full zero.
+ */
+size_t compress_lznt(const void *unc, size_t unc_size, void *cmpr,
+ size_t cmpr_size, struct lznt *ctx)
+{
+ int err;
+ size_t (*match)(const u8 *src, struct lznt *ctx);
+ u8 *p = cmpr;
+ u8 *end = p + cmpr_size;
+ const u8 *unc_chunk = unc;
+ const u8 *unc_end = unc_chunk + unc_size;
+ bool is_zero = true;
+
+ if (ctx->std) {
+ match = &longest_match_std;
+ memset(ctx->hash, 0, sizeof(ctx->hash));
+ } else {
+ match = &longest_match_best;
+ }
+
+ /* Compression cycle. */
+ for (; unc_chunk < unc_end; unc_chunk += LZNT_CHUNK_SIZE) {
+ cmpr_size = 0;
+ err = compress_chunk(match, unc_chunk, unc_end, p, end,
+ &cmpr_size, ctx);
+ if (err < 0)
+ return unc_size;
+
+ if (is_zero && err != LZNT_ERROR_ALL_ZEROS)
+ is_zero = false;
+
+ p += cmpr_size;
+ }
+
+ if (p <= end - 2)
+ p[0] = p[1] = 0;
+
+ return is_zero ? 0 : PtrOffset(cmpr, p);
+}
+
+/*
+ * decompress_lznt - Decompress @cmpr into @unc.
+ */
+ssize_t decompress_lznt(const void *cmpr, size_t cmpr_size, void *unc,
+ size_t unc_size)
+{
+ const u8 *cmpr_chunk = cmpr;
+ const u8 *cmpr_end = cmpr_chunk + cmpr_size;
+ u8 *unc_chunk = unc;
+ u8 *unc_end = unc_chunk + unc_size;
+ u16 chunk_hdr;
+
+ if (cmpr_size < sizeof(short))
+ return -EINVAL;
+
+ /* Read chunk header. */
+ chunk_hdr = cmpr_chunk[1];
+ chunk_hdr <<= 8;
+ chunk_hdr |= cmpr_chunk[0];
+
+ /* Loop through decompressing chunks. */
+ for (;;) {
+ size_t chunk_size_saved;
+ size_t unc_use;
+ size_t cmpr_use = 3 + (chunk_hdr & (LZNT_CHUNK_SIZE - 1));
+
+ /* Check that the chunk actually fits the supplied buffer. */
+ if (cmpr_chunk + cmpr_use > cmpr_end)
+ return -EINVAL;
+
+ /* First make sure the chunk contains compressed data. */
+ if (chunk_hdr & 0x8000) {
+ /* Decompress a chunk and return if we get an error. */
+ ssize_t err =
+ decompress_chunk(unc_chunk, unc_end,
+ cmpr_chunk + sizeof(chunk_hdr),
+ cmpr_chunk + cmpr_use);
+ if (err < 0)
+ return err;
+ unc_use = err;
+ } else {
+ /* This chunk does not contain compressed data. */
+ unc_use = unc_chunk + LZNT_CHUNK_SIZE > unc_end
+ ? unc_end - unc_chunk
+ : LZNT_CHUNK_SIZE;
+
+ if (cmpr_chunk + sizeof(chunk_hdr) + unc_use >
+ cmpr_end) {
+ return -EINVAL;
+ }
+
+ memcpy(unc_chunk, cmpr_chunk + sizeof(chunk_hdr),
+ unc_use);
+ }
+
+ /* Advance pointers. */
+ cmpr_chunk += cmpr_use;
+ unc_chunk += unc_use;
+
+ /* Check for the end of unc buffer. */
+ if (unc_chunk >= unc_end)
+ break;
+
+ /* Proceed the next chunk. */
+ if (cmpr_chunk > cmpr_end - 2)
+ break;
+
+ chunk_size_saved = LZNT_CHUNK_SIZE;
+
+ /* Read chunk header. */
+ chunk_hdr = cmpr_chunk[1];
+ chunk_hdr <<= 8;
+ chunk_hdr |= cmpr_chunk[0];
+
+ if (!chunk_hdr)
+ break;
+
+ /* Check the size of unc buffer. */
+ if (unc_use < chunk_size_saved) {
+ size_t t1 = chunk_size_saved - unc_use;
+ u8 *t2 = unc_chunk + t1;
+
+ /* 'Zero' memory. */
+ if (t2 >= unc_end)
+ break;
+
+ memset(unc_chunk, 0, t1);
+ unc_chunk = t2;
+ }
+ }
+
+ /* Check compression boundary. */
+ if (cmpr_chunk > cmpr_end)
+ return -EINVAL;
+
+ /*
+ * The unc size is just a difference between current
+ * pointer and original one.
+ */
+ return PtrOffset(unc, unc_chunk);
+}