diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Kconfig | 9 | ||||
-rw-r--r-- | lib/Kconfig.debug | 3 | ||||
-rw-r--r-- | lib/Makefile | 10 | ||||
-rw-r--r-- | lib/average.c | 61 | ||||
-rw-r--r-- | lib/decompress.c | 5 | ||||
-rw-r--r-- | lib/decompress_bunzip2.c | 8 | ||||
-rw-r--r-- | lib/decompress_inflate.c | 23 | ||||
-rw-r--r-- | lib/decompress_unlzma.c | 85 | ||||
-rw-r--r-- | lib/decompress_unlzo.c | 105 | ||||
-rw-r--r-- | lib/decompress_unxz.c | 397 | ||||
-rw-r--r-- | lib/dynamic_debug.c | 9 | ||||
-rw-r--r-- | lib/flex_array.c | 10 | ||||
-rw-r--r-- | lib/hexdump.c | 18 | ||||
-rw-r--r-- | lib/kref.c | 30 | ||||
-rw-r--r-- | lib/nlattr.c | 22 | ||||
-rw-r--r-- | lib/percpu_counter.c | 8 | ||||
-rw-r--r-- | lib/timerqueue.c | 107 | ||||
-rw-r--r-- | lib/vsprintf.c | 38 | ||||
-rw-r--r-- | lib/xz/Kconfig | 59 | ||||
-rw-r--r-- | lib/xz/Makefile | 5 | ||||
-rw-r--r-- | lib/xz/xz_crc32.c | 59 | ||||
-rw-r--r-- | lib/xz/xz_dec_bcj.c | 561 | ||||
-rw-r--r-- | lib/xz/xz_dec_lzma2.c | 1171 | ||||
-rw-r--r-- | lib/xz/xz_dec_stream.c | 821 | ||||
-rw-r--r-- | lib/xz/xz_dec_syms.c | 26 | ||||
-rw-r--r-- | lib/xz/xz_dec_test.c | 220 | ||||
-rw-r--r-- | lib/xz/xz_lzma2.h | 204 | ||||
-rw-r--r-- | lib/xz/xz_private.h | 156 | ||||
-rw-r--r-- | lib/xz/xz_stream.h | 62 |
29 files changed, 4194 insertions, 98 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index fa9bf2c0619..0ee67e08ad3 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -106,6 +106,8 @@ config LZO_COMPRESS config LZO_DECOMPRESS tristate +source "lib/xz/Kconfig" + # # These all provide a common interface (hence the apparent duplication with # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) @@ -120,6 +122,10 @@ config DECOMPRESS_BZIP2 config DECOMPRESS_LZMA tristate +config DECOMPRESS_XZ + select XZ_DEC + tristate + config DECOMPRESS_LZO select LZO_DECOMPRESS tristate @@ -210,4 +216,7 @@ config GENERIC_ATOMIC64 config LRU_CACHE tristate +config AVERAGE + bool + endmenu diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 28b42b9274d..2d05adb9840 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -173,7 +173,8 @@ config LOCKUP_DETECTOR An NMI is generated every 60 seconds or so to check for hardlockups. config HARDLOCKUP_DETECTOR - def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI + def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI && \ + !ARCH_HAS_NMI_WATCHDOG config BOOTPARAM_SOFTLOCKUP_PANIC bool "Panic (Reboot) On Soft Lockups" diff --git a/lib/Makefile b/lib/Makefile index e6a3763b821..cbb774f7d41 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -8,11 +8,11 @@ KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS)) endif lib-y := ctype.o string.o vsprintf.o cmdline.o \ - rbtree.o radix-tree.o dump_stack.o \ + rbtree.o radix-tree.o dump_stack.o timerqueue.o\ idr.o int_sqrt.o extable.o prio_tree.o \ sha1.o irq_regs.o reciprocal_div.o argv_split.o \ proportions.o prio_heap.o ratelimit.o show_mem.o \ - is_single_threaded.o plist.o decompress.o flex_array.o + is_single_threaded.o plist.o decompress.o lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_SMP) += cpumask.o @@ -21,7 +21,7 @@ lib-y += kobject.o kref.o klist.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ - string_helpers.o gcd.o lcm.o list_sort.o uuid.o + string_helpers.o gcd.o lcm.o list_sort.o uuid.o flex_array.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG @@ -69,11 +69,13 @@ obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate/ obj-$(CONFIG_REED_SOLOMON) += reed_solomon/ obj-$(CONFIG_LZO_COMPRESS) += lzo/ obj-$(CONFIG_LZO_DECOMPRESS) += lzo/ +obj-$(CONFIG_XZ_DEC) += xz/ obj-$(CONFIG_RAID6_PQ) += raid6/ lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o +lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o obj-$(CONFIG_TEXTSEARCH) += textsearch.o @@ -106,6 +108,8 @@ obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o +obj-$(CONFIG_AVERAGE) += average.o + hostprogs-y := gen_crc32table clean-files := crc32table.h diff --git a/lib/average.c b/lib/average.c new file mode 100644 index 00000000000..5576c284149 --- /dev/null +++ b/lib/average.c @@ -0,0 +1,61 @@ +/* + * lib/average.c + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include <linux/module.h> +#include <linux/average.h> +#include <linux/bug.h> +#include <linux/log2.h> + +/** + * DOC: Exponentially Weighted Moving Average (EWMA) + * + * These are generic functions for calculating Exponentially Weighted Moving + * Averages (EWMA). We keep a structure with the EWMA parameters and a scaled + * up internal representation of the average value to prevent rounding errors. + * The factor for scaling up and the exponential weight (or decay rate) have to + * be specified thru the init fuction. The structure should not be accessed + * directly but only thru the helper functions. + */ + +/** + * ewma_init() - Initialize EWMA parameters + * @avg: Average structure + * @factor: Factor to use for the scaled up internal value. The maximum value + * of averages can be ULONG_MAX/(factor*weight). For performance reasons + * factor has to be a power of 2. + * @weight: Exponential weight, or decay rate. This defines how fast the + * influence of older values decreases. For performance reasons weight has + * to be a power of 2. + * + * Initialize the EWMA parameters for a given struct ewma @avg. + */ +void ewma_init(struct ewma *avg, unsigned long factor, unsigned long weight) +{ + WARN_ON(!is_power_of_2(weight) || !is_power_of_2(factor)); + + avg->weight = ilog2(weight); + avg->factor = ilog2(factor); + avg->internal = 0; +} +EXPORT_SYMBOL(ewma_init); + +/** + * ewma_add() - Exponentially weighted moving average (EWMA) + * @avg: Average structure + * @val: Current value + * + * Add a sample to the average. + */ +struct ewma *ewma_add(struct ewma *avg, unsigned long val) +{ + avg->internal = avg->internal ? + (((avg->internal << avg->weight) - avg->internal) + + (val << avg->factor)) >> avg->weight : + (val << avg->factor); + return avg; +} +EXPORT_SYMBOL(ewma_add); diff --git a/lib/decompress.c b/lib/decompress.c index a7606815541..3d766b7f60a 100644 --- a/lib/decompress.c +++ b/lib/decompress.c @@ -8,6 +8,7 @@ #include <linux/decompress/bunzip2.h> #include <linux/decompress/unlzma.h> +#include <linux/decompress/unxz.h> #include <linux/decompress/inflate.h> #include <linux/decompress/unlzo.h> @@ -23,6 +24,9 @@ #ifndef CONFIG_DECOMPRESS_LZMA # define unlzma NULL #endif +#ifndef CONFIG_DECOMPRESS_XZ +# define unxz NULL +#endif #ifndef CONFIG_DECOMPRESS_LZO # define unlzo NULL #endif @@ -36,6 +40,7 @@ static const struct compress_format { { {037, 0236}, "gzip", gunzip }, { {0x42, 0x5a}, "bzip2", bunzip2 }, { {0x5d, 0x00}, "lzma", unlzma }, + { {0xfd, 0x37}, "xz", unxz }, { {0x89, 0x4c}, "lzo", unlzo }, { {0, 0}, NULL, NULL } }; diff --git a/lib/decompress_bunzip2.c b/lib/decompress_bunzip2.c index 81c8bb1cc6a..a7b80c1d6a0 100644 --- a/lib/decompress_bunzip2.c +++ b/lib/decompress_bunzip2.c @@ -49,7 +49,6 @@ #define PREBOOT #else #include <linux/decompress/bunzip2.h> -#include <linux/slab.h> #endif /* STATIC */ #include <linux/decompress/mm.h> @@ -682,13 +681,12 @@ STATIC int INIT bunzip2(unsigned char *buf, int len, int(*flush)(void*, unsigned int), unsigned char *outbuf, int *pos, - void(*error_fn)(char *x)) + void(*error)(char *x)) { struct bunzip_data *bd; int i = -1; unsigned char *inbuf; - set_error_fn(error_fn); if (flush) outbuf = malloc(BZIP2_IOBUF_SIZE); @@ -751,8 +749,8 @@ STATIC int INIT decompress(unsigned char *buf, int len, int(*flush)(void*, unsigned int), unsigned char *outbuf, int *pos, - void(*error_fn)(char *x)) + void(*error)(char *x)) { - return bunzip2(buf, len - 4, fill, flush, outbuf, pos, error_fn); + return bunzip2(buf, len - 4, fill, flush, outbuf, pos, error); } #endif diff --git a/lib/decompress_inflate.c b/lib/decompress_inflate.c index fc686c7a0a0..19ff89e34ee 100644 --- a/lib/decompress_inflate.c +++ b/lib/decompress_inflate.c @@ -19,7 +19,6 @@ #include "zlib_inflate/inflate.h" #include "zlib_inflate/infutil.h" -#include <linux/slab.h> #endif /* STATIC */ @@ -27,7 +26,7 @@ #define GZIP_IOBUF_SIZE (16*1024) -static int nofill(void *buffer, unsigned int len) +static int INIT nofill(void *buffer, unsigned int len) { return -1; } @@ -38,13 +37,12 @@ STATIC int INIT gunzip(unsigned char *buf, int len, int(*flush)(void*, unsigned int), unsigned char *out_buf, int *pos, - void(*error_fn)(char *x)) { + void(*error)(char *x)) { u8 *zbuf; struct z_stream_s *strm; int rc; size_t out_len; - set_error_fn(error_fn); rc = -1; if (flush) { out_len = 0x8000; /* 32 K */ @@ -100,13 +98,22 @@ STATIC int INIT gunzip(unsigned char *buf, int len, * possible asciz filename) */ strm->next_in = zbuf + 10; + strm->avail_in = len - 10; /* skip over asciz filename */ if (zbuf[3] & 0x8) { - while (strm->next_in[0]) - strm->next_in++; - strm->next_in++; + do { + /* + * If the filename doesn't fit into the buffer, + * the file is very probably corrupt. Don't try + * to read more data. + */ + if (strm->avail_in == 0) { + error("header error"); + goto gunzip_5; + } + --strm->avail_in; + } while (*strm->next_in++); } - strm->avail_in = len - (strm->next_in - zbuf); strm->next_out = out_buf; strm->avail_out = out_len; diff --git a/lib/decompress_unlzma.c b/lib/decompress_unlzma.c index ca82fde81c8..476c65af970 100644 --- a/lib/decompress_unlzma.c +++ b/lib/decompress_unlzma.c @@ -33,7 +33,6 @@ #define PREBOOT #else #include <linux/decompress/unlzma.h> -#include <linux/slab.h> #endif /* STATIC */ #include <linux/decompress/mm.h> @@ -74,6 +73,7 @@ struct rc { uint32_t code; uint32_t range; uint32_t bound; + void (*error)(char *); }; @@ -82,7 +82,7 @@ struct rc { #define RC_MODEL_TOTAL_BITS 11 -static int nofill(void *buffer, unsigned int len) +static int INIT nofill(void *buffer, unsigned int len) { return -1; } @@ -92,7 +92,7 @@ static void INIT rc_read(struct rc *rc) { rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE); if (rc->buffer_size <= 0) - error("unexpected EOF"); + rc->error("unexpected EOF"); rc->ptr = rc->buffer; rc->buffer_end = rc->buffer + rc->buffer_size; } @@ -127,12 +127,6 @@ static inline void INIT rc_init_code(struct rc *rc) } -/* Called once. TODO: bb_maybe_free() */ -static inline void INIT rc_free(struct rc *rc) -{ - free(rc->buffer); -} - /* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */ static void INIT rc_do_normalize(struct rc *rc) { @@ -169,7 +163,7 @@ static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p) rc->range = rc->bound; *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS; } -static inline void rc_update_bit_1(struct rc *rc, uint16_t *p) +static inline void INIT rc_update_bit_1(struct rc *rc, uint16_t *p) { rc->range -= rc->bound; rc->code -= rc->bound; @@ -319,32 +313,38 @@ static inline uint8_t INIT peek_old_byte(struct writer *wr, } -static inline void INIT write_byte(struct writer *wr, uint8_t byte) +static inline int INIT write_byte(struct writer *wr, uint8_t byte) { wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte; if (wr->flush && wr->buffer_pos == wr->header->dict_size) { wr->buffer_pos = 0; wr->global_pos += wr->header->dict_size; - wr->flush((char *)wr->buffer, wr->header->dict_size); + if (wr->flush((char *)wr->buffer, wr->header->dict_size) + != wr->header->dict_size) + return -1; } + return 0; } -static inline void INIT copy_byte(struct writer *wr, uint32_t offs) +static inline int INIT copy_byte(struct writer *wr, uint32_t offs) { - write_byte(wr, peek_old_byte(wr, offs)); + return write_byte(wr, peek_old_byte(wr, offs)); } -static inline void INIT copy_bytes(struct writer *wr, +static inline int INIT copy_bytes(struct writer *wr, uint32_t rep0, int len) { do { - copy_byte(wr, rep0); + if (copy_byte(wr, rep0)) + return -1; len--; } while (len != 0 && wr->buffer_pos < wr->header->dst_size); + + return len; } -static inline void INIT process_bit0(struct writer *wr, struct rc *rc, +static inline int INIT process_bit0(struct writer *wr, struct rc *rc, struct cstate *cst, uint16_t *p, int pos_state, uint16_t *prob, int lc, uint32_t literal_pos_mask) { @@ -378,16 +378,17 @@ static inline void INIT process_bit0(struct writer *wr, struct rc *rc, uint16_t *prob_lit = prob + mi; rc_get_bit(rc, prob_lit, &mi); } - write_byte(wr, mi); if (cst->state < 4) cst->state = 0; else if (cst->state < 10) cst->state -= 3; else cst->state -= 6; + + return write_byte(wr, mi); } -static inline void INIT process_bit1(struct writer *wr, struct rc *rc, +static inline int INIT process_bit1(struct writer *wr, struct rc *rc, struct cstate *cst, uint16_t *p, int pos_state, uint16_t *prob) { int offset; @@ -418,8 +419,7 @@ static inline void INIT process_bit1(struct writer *wr, struct rc *rc, cst->state = cst->state < LZMA_NUM_LIT_STATES ? 9 : 11; - copy_byte(wr, cst->rep0); - return; + return copy_byte(wr, cst->rep0); } else { rc_update_bit_1(rc, prob); } @@ -521,12 +521,15 @@ static inline void INIT process_bit1(struct writer *wr, struct rc *rc, } else cst->rep0 = pos_slot; if (++(cst->rep0) == 0) - return; + return 0; + if (cst->rep0 > wr->header->dict_size + || cst->rep0 > get_pos(wr)) + return -1; } len += LZMA_MATCH_MIN_LEN; - copy_bytes(wr, cst->rep0, len); + return copy_bytes(wr, cst->rep0, len); } @@ -536,7 +539,7 @@ STATIC inline int INIT unlzma(unsigned char *buf, int in_len, int(*flush)(void*, unsigned int), unsigned char *output, int *posp, - void(*error_fn)(char *x) + void(*error)(char *x) ) { struct lzma_header header; @@ -552,7 +555,7 @@ STATIC inline int INIT unlzma(unsigned char *buf, int in_len, unsigned char *inbuf; int ret = -1; - set_error_fn(error_fn); + rc.error = error; if (buf) inbuf = buf; @@ -580,8 +583,10 @@ STATIC inline int INIT unlzma(unsigned char *buf, int in_len, ((unsigned char *)&header)[i] = *rc.ptr++; } - if (header.pos >= (9 * 5 * 5)) + if (header.pos >= (9 * 5 * 5)) { error("bad header"); + goto exit_1; + } mi = 0; lc = header.pos; @@ -627,21 +632,29 @@ STATIC inline int INIT unlzma(unsigned char *buf, int in_len, int pos_state = get_pos(&wr) & pos_state_mask; uint16_t *prob = p + LZMA_IS_MATCH + (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state; - if (rc_is_bit_0(&rc, prob)) - process_bit0(&wr, &rc, &cst, p, pos_state, prob, - lc, literal_pos_mask); - else { - process_bit1(&wr, &rc, &cst, p, pos_state, prob); + if (rc_is_bit_0(&rc, prob)) { + if (process_bit0(&wr, &rc, &cst, p, pos_state, prob, + lc, literal_pos_mask)) { + error("LZMA data is corrupt"); + goto exit_3; + } + } else { + if (process_bit1(&wr, &rc, &cst, p, pos_state, prob)) { + error("LZMA data is corrupt"); + goto exit_3; + } if (cst.rep0 == 0) break; } + if (rc.buffer_size <= 0) + goto exit_3; } if (posp) *posp = rc.ptr-rc.buffer; - if (wr.flush) - wr.flush(wr.buffer, wr.buffer_pos); - ret = 0; + if (!wr.flush || wr.flush(wr.buffer, wr.buffer_pos) == wr.buffer_pos) + ret = 0; +exit_3: large_free(p); exit_2: if (!output) @@ -659,9 +672,9 @@ STATIC int INIT decompress(unsigned char *buf, int in_len, int(*flush)(void*, unsigned int), unsigned char *output, int *posp, - void(*error_fn)(char *x) + void(*error)(char *x) ) { - return unlzma(buf, in_len - 4, fill, flush, output, posp, error_fn); + return unlzma(buf, in_len - 4, fill, flush, output, posp, error); } #endif diff --git a/lib/decompress_unlzo.c b/lib/decompress_unlzo.c index bcb3a4bd68f..5a7a2adf4c4 100644 --- a/lib/decompress_unlzo.c +++ b/lib/decompress_unlzo.c @@ -33,7 +33,6 @@ #ifdef STATIC #include "lzo/lzo1x_decompress.c" #else -#include <linux/slab.h> #include <linux/decompress/unlzo.h> #endif @@ -49,14 +48,25 @@ static const unsigned char lzop_magic[] = { #define LZO_BLOCK_SIZE (256*1024l) #define HEADER_HAS_FILTER 0x00000800L +#define HEADER_SIZE_MIN (9 + 7 + 4 + 8 + 1 + 4) +#define HEADER_SIZE_MAX (9 + 7 + 1 + 8 + 8 + 4 + 1 + 255 + 4) -STATIC inline int INIT parse_header(u8 *input, u8 *skip) +STATIC inline int INIT parse_header(u8 *input, int *skip, int in_len) { int l; u8 *parse = input; + u8 *end = input + in_len; u8 level = 0; u16 version; + /* + * Check that there's enough input to possibly have a valid header. + * Then it is possible to parse several fields until the minimum + * size may have been used. + */ + if (in_len < HEADER_SIZE_MIN) + return 0; + /* read magic: 9 first bits */ for (l = 0; l < 9; l++) { if (*parse++ != lzop_magic[l]) @@ -74,6 +84,15 @@ STATIC inline int INIT parse_header(u8 *input, u8 *skip) else parse += 4; /* flags */ + /* + * At least mode, mtime_low, filename length, and checksum must + * be left to be parsed. If also mtime_high is present, it's OK + * because the next input buffer check is after reading the + * filename length. + */ + if (end - parse < 8 + 1 + 4) + return 0; + /* skip mode and mtime_low */ parse += 8; if (version >= 0x0940) @@ -81,6 +100,8 @@ STATIC inline int INIT parse_header(u8 *input, u8 *skip) l = *parse++; /* don't care about the file name, and skip checksum */ + if (end - parse < l + 4) + return 0; parse += l + 4; *skip = parse - input; @@ -91,16 +112,15 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, int (*fill) (void *, unsigned int), int (*flush) (void *, unsigned int), u8 *output, int *posp, - void (*error_fn) (char *x)) + void (*error) (char *x)) { - u8 skip = 0, r = 0; + u8 r = 0; + int skip = 0; u32 src_len, dst_len; size_t tmp; u8 *in_buf, *in_buf_save, *out_buf; int ret = -1; - set_error_fn(error_fn); - if (output) { out_buf = output; } else if (!flush) { @@ -119,8 +139,8 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, goto exit_1; } else if (input) { in_buf = input; - } else if (!fill || !posp) { - error("NULL input pointer and missing position pointer or fill function"); + } else if (!fill) { + error("NULL input pointer and missing fill function"); goto exit_1; } else { in_buf = malloc(lzo1x_worst_compress(LZO_BLOCK_SIZE)); @@ -134,22 +154,47 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, if (posp) *posp = 0; - if (fill) - fill(in_buf, lzo1x_worst_compress(LZO_BLOCK_SIZE)); + if (fill) { + /* + * Start from in_buf + HEADER_SIZE_MAX to make it possible + * to use memcpy() to copy the unused data to the beginning + * of the buffer. This way memmove() isn't needed which + * is missing from pre-boot environments of most archs. + */ + in_buf += HEADER_SIZE_MAX; + in_len = fill(in_buf, HEADER_SIZE_MAX); + } - if (!parse_header(input, &skip)) { + if (!parse_header(in_buf, &skip, in_len)) { error("invalid header"); goto exit_2; } in_buf += skip; + in_len -= skip; + + if (fill) { + /* Move the unused data to the beginning of the buffer. */ + memcpy(in_buf_save, in_buf, in_len); + in_buf = in_buf_save; + } if (posp) *posp = skip; for (;;) { /* read uncompressed block size */ + if (fill && in_len < 4) { + skip = fill(in_buf + in_len, 4 - in_len); + if (skip > 0) + in_len += skip; + } + if (in_len < 4) { + error("file corrupted"); + goto exit_2; + } dst_len = get_unaligned_be32(in_buf); in_buf += 4; + in_len -= 4; /* exit if last block */ if (dst_len == 0) { @@ -164,8 +209,18 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, } /* read compressed block size, and skip block checksum info */ + if (fill && in_len < 8) { + skip = fill(in_buf + in_len, 8 - in_len); + if (skip > 0) + in_len += skip; + } + if (in_len < 8) { + error("file corrupted"); + goto exit_2; + } src_len = get_unaligned_be32(in_buf); in_buf += 8; + in_len -= 8; if (src_len <= 0 || src_len > dst_len) { error("file corrupted"); @@ -173,6 +228,15 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, } /* decompress */ + if (fill && in_len < src_len) { + skip = fill(in_buf + in_len, src_len - in_len); + if (skip > 0) + in_len += skip; + } + if (in_len < src_len) { + error("file corrupted"); + goto exit_2; + } tmp = dst_len; /* When the input data is not compressed at all, @@ -190,17 +254,26 @@ STATIC inline int INIT unlzo(u8 *input, int in_len, } } - if (flush) - flush(out_buf, dst_len); + if (flush && flush(out_buf, dst_len) != dst_len) + goto exit_2; if (output) out_buf += dst_len; if (posp) *posp += src_len + 12; + + in_buf += src_len; + in_len -= src_len; if (fill) { + /* + * If there happens to still be unused data left in + * in_buf, move it to the beginning of the buffer. + * Use a loop to avoid memmove() dependency. + */ + if (in_len > 0) + for (skip = 0; skip < in_len; ++skip) + in_buf_save[skip] = in_buf[skip]; in_buf = in_buf_save; - fill(in_buf, lzo1x_worst_compress(LZO_BLOCK_SIZE)); - } else - in_buf += src_len; + } } ret = 0; diff --git a/lib/decompress_unxz.c b/lib/decompress_unxz.c new file mode 100644 index 00000000000..cecd23df2b9 --- /dev/null +++ b/lib/decompress_unxz.c @@ -0,0 +1,397 @@ +/* + * Wrapper for decompressing XZ-compressed kernel, initramfs, and initrd + * + * Author: Lasse Collin <lasse.collin@tukaani.org> + * + * This file has been put into the public domain. + * You can do whatever you want with this file. + */ + +/* + * Important notes about in-place decompression + * + * At least on x86, the kernel is decompressed in place: the compressed data + * is placed to the end of the output buffer, and the decompressor overwrites + * most of the compressed data. There must be enough safety margin to + * guarantee that the write position is always behind the read position. + * + * The safety margin for XZ with LZMA2 or BCJ+LZMA2 is calculated below. + * Note that the margin with XZ is bigger than with Deflate (gzip)! + * + * The worst case for in-place decompression is that the beginning of + * the file is compressed extremely well, and the rest of the file is + * uncompressible. Thus, we must look for worst-case expansion when the + * compressor is encoding uncompressible data. + * + * The structure of the .xz file in case of a compresed kernel is as follows. + * Sizes (as bytes) of the fields are in parenthesis. + * + * Stream Header (12) + * Block Header: + * Block Header (8-12) + * Compressed Data (N) + * Block Padding (0-3) + * CRC32 (4) + * Index (8-20) + * Stream Footer (12) + * + * Normally there is exactly one Block, but let's assume that there are + * 2-4 Blocks just in case. Because Stream Header and also Block Header + * of the first Block don't make the decompressor produce any uncompressed + * data, we can ignore them from our calculations. Block Headers of possible + * additional Blocks have to be taken into account still. With these + * assumptions, it is safe to assume that the total header overhead is + * less than 128 bytes. + * + * Compressed Data contains LZMA2 or BCJ+LZMA2 encoded data. Since BCJ + * doesn't change the size of the data, it is enough to calculate the + * safety margin for LZMA2. + * + * LZMA2 stores the data in chunks. Each chunk has a header whose size is + * a maximum of 6 bytes, but to get round 2^n numbers, let's assume that + * the maximum chunk header size is 8 bytes. After the chunk header, there + * may be up to 64 KiB of actual payload in the chunk. Often the payload is + * quite a bit smaller though; to be safe, let's assume that an average + * chunk has only 32 KiB of payload. + * + * The maximum uncompressed size of the payload is 2 MiB. The minimum + * uncompressed size of the payload is in practice never less than the + * payload size itself. The LZMA2 format would allow uncompressed size + * to be less than the payload size, but no sane compressor creates such + * files. LZMA2 supports storing uncompressible data in uncompressed form, + * so there's never a need to create payloads whose uncompressed size is + * smaller than the compressed size. + * + * The assumption, that the uncompressed size of the payload is never + * smaller than the payload itself, is valid only when talking about + * the payload as a whole. It is possible that the payload has parts where + * the decompressor consumes more input than it produces output. Calculating + * the worst case for this would be tricky. Instead of trying to do that, + * let's simply make sure that the decompressor never overwrites any bytes + * of the payload which it is currently reading. + * + * Now we have enough information to calculate the safety margin. We need + * - 128 bytes for the .xz file format headers; + * - 8 bytes per every 32 KiB of uncompressed size (one LZMA2 chunk header + * per chunk, each chunk having average payload size of 32 KiB); and + * - 64 KiB (biggest possible LZMA2 chunk payload size) to make sure that + * the decompressor never overwrites anything from the LZMA2 chunk + * payload it is currently reading. + * + * We get the following formula: + * + * safety_margin = 128 + uncompressed_size * 8 / 32768 + 65536 + * = 128 + (uncompressed_size >> 12) + 65536 + * + * For comparision, according to arch/x86/boot/compressed/misc.c, the + * equivalent formula for Deflate is this: + * + * safety_margin = 18 + (uncompressed_size >> 12) + 32768 + * + * Thus, when updating Deflate-only in-place kernel decompressor to + * support XZ, the fixed overhead has to be increased from 18+32768 bytes + * to 128+65536 bytes. + */ + +/* + * STATIC is defined to "static" if we are being built for kernel + * decompression (pre-boot code). <linux/decompress/mm.h> will define + * STATIC to empty if it wasn't already defined. Since we will need to + * know later if we are being used for kernel decompression, we define + * XZ_PREBOOT here. + */ +#ifdef STATIC +# define XZ_PREBOOT +#endif +#ifdef __KERNEL__ +# include <linux/decompress/mm.h> +#endif +#define XZ_EXTERN STATIC + +#ifndef XZ_PREBOOT +# include <linux/slab.h> +# include <linux/xz.h> +#else +/* + * Use the internal CRC32 code instead of kernel's CRC32 module, which + * is not available in early phase of booting. + */ +#define XZ_INTERNAL_CRC32 1 + +/* + * For boot time use, we enable only the BCJ filter of the current + * architecture or none if no BCJ filter is available for the architecture. + */ +#ifdef CONFIG_X86 +# define XZ_DEC_X86 +#endif |