get rid of dynamic buffer struct allocation during pcomp lzma decompression and instead force the caller to provide the maximum buffer list size

SVN-Revision: 17475
v19.07.3_mercusys_ac12_duma
Felix Fietkau 15 years ago
parent b5e6d76dea
commit eda566c4e9

@ -1,6 +1,6 @@
--- /dev/null
+++ b/crypto/unlzma.c
@@ -0,0 +1,723 @@
@@ -0,0 +1,748 @@
+/*
+ * LZMA uncompresion module for pcomp
+ * Copyright (C) 2009 Felix Fietkau <nbd@openwrt.org>
@ -36,12 +36,12 @@
+#include <linux/kthread.h>
+
+#include <crypto/internal/compress.h>
+#include <net/netlink.h>
+#include "unlzma.h"
+
+static int instance = 0;
+
+struct unlzma_buffer {
+ struct unlzma_buffer *last;
+ int offset;
+ int size;
+ u8 *ptr;
@ -68,8 +68,10 @@
+ /* writer state */
+ u8 previous_byte;
+ ssize_t pos;
+ struct unlzma_buffer *head;
+ int buf_full;
+ int n_buffers;
+ int buffers_max;
+ struct unlzma_buffer *buffers;
+
+ /* cstate */
+ int state;
@ -92,12 +94,11 @@
+{
+ struct unlzma_buffer *bh;
+
+ bh = kzalloc(sizeof(struct unlzma_buffer), GFP_KERNEL);
+ BUG_ON(ctx->n_buffers >= ctx->buffers_max);
+ bh = &ctx->buffers[ctx->n_buffers++];
+ bh->ptr = ctx->next_out;
+ bh->offset = ctx->pos;
+ bh->last = ctx->head;
+ bh->size = ctx->avail_out;
+ ctx->head = bh;
+ ctx->buf_full = 0;
+}
+
@ -208,17 +209,20 @@
+static u8
+peek_old_byte(struct unlzma_ctx *ctx, u32 offs)
+{
+ struct unlzma_buffer *bh = ctx->head;
+ struct unlzma_buffer *bh = &ctx->buffers[ctx->n_buffers - 1];
+ int i = ctx->n_buffers;
+ u32 pos;
+
+ BUG_ON(!ctx->n_buffers);
+ pos = ctx->pos - offs;
+ if (pos >= ctx->dict_size) {
+ pos = (~pos % ctx->dict_size);
+ }
+
+ while (bh->offset > pos) {
+ bh = bh->last;
+ BUG_ON(!bh);
+ bh--;
+ i--;
+ BUG_ON(!i);
+ }
+
+ pos -= bh->offset;
@ -460,6 +464,7 @@
+ hdr_buf[i] = rc_read(ctx);
+ }
+
+ ctx->n_buffers = 0;
+ ctx->pos = 0;
+ get_buffer(ctx);
+ ctx->active = true;
@ -554,11 +559,6 @@
+ unlzma_reset_buf(ctx);
+ ctx->cancel = false;
+ ctx->active = false;
+ while (ctx->head) {
+ struct unlzma_buffer *bh = ctx->head;
+ ctx->head = bh->last;
+ kfree(bh);
+ }
+ } while (!kthread_should_stop());
+ mutex_unlock(&ctx->mutex);
+ return 0;
@ -598,6 +598,10 @@
+ unlzma_cancel(ctx);
+ kthread_stop(ctx->thread);
+ ctx->thread = NULL;
+ if (ctx->buffers)
+ kfree(ctx->buffers);
+ ctx->buffers_max = 0;
+ ctx->buffers = NULL;
+ }
+}
+
@ -605,10 +609,31 @@
+unlzma_decompress_setup(struct crypto_pcomp *tfm, void *p, unsigned int len)
+{
+ struct unlzma_ctx *ctx = crypto_tfm_ctx(crypto_pcomp_tfm(tfm));
+ struct nlattr *tb[UNLZMA_DECOMP_MAX + 1];
+ int ret = 0;
+
+ if (ctx->thread)
+ return 0;
+ return -EINVAL;
+
+ if (!p)
+ return -EINVAL;
+
+ ret = nla_parse(tb, UNLZMA_DECOMP_MAX, p, len, NULL);
+ if (!tb[UNLZMA_DECOMP_OUT_BUFFERS])
+ return -EINVAL;
+
+ if (ctx->buffers_max && (ctx->buffers_max <
+ nla_get_u32(tb[UNLZMA_DECOMP_OUT_BUFFERS]))) {
+ kfree(ctx->buffers);
+ ctx->buffers_max = 0;
+ ctx->buffers = NULL;
+ }
+ if (!ctx->buffers) {
+ ctx->buffers_max = nla_get_u32(tb[UNLZMA_DECOMP_OUT_BUFFERS]);
+ ctx->buffers = kzalloc(sizeof(struct unlzma_buffer) * ctx->buffers_max, GFP_KERNEL);
+ }
+ if (!ctx->buffers)
+ return -ENOMEM;
+
+ mutex_init(&ctx->mutex);
+ init_waitqueue_head(&ctx->next_req);
@ -832,3 +857,18 @@
+#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
+
+#endif
--- a/include/crypto/compress.h
+++ b/include/crypto/compress.h
@@ -49,6 +49,12 @@ enum zlib_decomp_params {
#define ZLIB_DECOMP_MAX (__ZLIB_DECOMP_MAX - 1)
+enum unlzma_decomp_params {
+ UNLZMA_DECOMP_OUT_BUFFERS = 1, /* naximum number of output buffers */
+ __UNLZMA_DECOMP_MAX,
+};
+#define UNLZMA_DECOMP_MAX (__UNLZMA_DECOMP_MAX - 1)
+
struct crypto_pcomp {
struct crypto_tfm base;

@ -47,7 +47,7 @@
__le32 s_magic;
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -47,13 +47,65 @@
@@ -47,13 +47,76 @@
#include "squashfs.h"
@ -81,7 +81,7 @@
+ crypto_free_pcomp(msblk->tfm);
+ }
+#endif
+
+ return err;
+}
+
@ -90,6 +90,17 @@
+ int err = -EOPNOTSUPP;
+
+#ifdef CONFIG_SQUASHFS_SUPPORT_LZMA
+ struct {
+ struct nlattr nla;
+ int val;
+ } params = {
+ .nla = {
+ .nla_len = nla_attr_size(sizeof(int)),
+ .nla_type = UNLZMA_DECOMP_OUT_BUFFERS,
+ },
+ .val = (msblk->block_size / PAGE_CACHE_SIZE) + 1
+ };
+ msblk->tfm = crypto_alloc_pcomp("lzma", 0,
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(msblk->tfm)) {
@ -97,7 +108,7 @@
+ return PTR_ERR(msblk->tfm);
+ }
+
+ err = crypto_decompress_setup(msblk->tfm, NULL, 0);
+ err = crypto_decompress_setup(msblk->tfm, &params, sizeof(params));
+ if (err) {
+ ERROR("Failed to set up decompression parameters\n");
+ crypto_free_pcomp(msblk->tfm);
@ -115,7 +126,7 @@
{
if (major < SQUASHFS_MAJOR) {
ERROR("Major/Minor mismatch, older Squashfs %d.%d "
@@ -66,9 +118,6 @@ static int supported_squashfs_filesystem
@@ -66,9 +129,6 @@ static int supported_squashfs_filesystem
return -EINVAL;
}
@ -125,7 +136,7 @@
return 0;
}
@@ -83,16 +132,6 @@ static int squashfs_fill_super(struct su
@@ -83,16 +143,6 @@ static int squashfs_fill_super(struct su
unsigned short flags;
unsigned int fragments;
u64 lookup_table_start;
@ -142,7 +153,7 @@
int err;
TRACE("Entered squashfs_fill_superblock\n");
@@ -104,21 +143,6 @@ static int squashfs_fill_super(struct su
@@ -104,21 +154,6 @@ static int squashfs_fill_super(struct su
}
msblk = sb->s_fs_info;
@ -164,8 +175,15 @@
sblk = kzalloc(sizeof(*sblk), GFP_KERNEL);
if (sblk == NULL) {
ERROR("Failed to allocate squashfs_super_block\n");
@@ -158,8 +182,21 @@ static int squashfs_fill_super(struct su
@@ -156,10 +191,28 @@ static int squashfs_fill_super(struct su
goto failed_mount;
}
+ /* Check block size for sanity */
+ msblk->block_size = le32_to_cpu(sblk->block_size);
+ if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
+ goto failed_mount;
+
/* Check the MAJOR & MINOR versions and compression type */
err = supported_squashfs_filesystem(le16_to_cpu(sblk->s_major),
- le16_to_cpu(sblk->s_minor),
@ -188,7 +206,19 @@
if (err < 0)
goto failed_mount;
@@ -315,21 +352,16 @@ allocate_root:
@@ -179,11 +232,6 @@ static int squashfs_fill_super(struct su
i_size_read(sb->s_bdev->bd_inode))
goto failed_mount;
- /* Check block size for sanity */
- msblk->block_size = le32_to_cpu(sblk->block_size);
- if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
- goto failed_mount;
-
/*
* Check the system page size is not larger than the filesystem
* block size (by default 128K). This is currently not supported.
@@ -315,21 +363,16 @@ allocate_root:
return 0;
failed_mount:

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