isofs compress: Remove VLA usage (5ac7c2fd) · Commits · 戴 / test

fs/isofs/compress.c

+16 −3

Original line number	Diff line number	Diff line
		@@ -20,6 +20,7 @@
		#include <linux/init.h>
		#include <linux/bio.h>

		#include <linux/slab.h>
		#include <linux/vmalloc.h>
		#include <linux/zlib.h>

		@@ -59,7 +60,7 @@ static loff_t zisofs_uncompress_block(struct inode *inode, loff_t block_start,
		>> bufshift;
		int haveblocks;
		blkcnt_t blocknum;
		struct buffer_head *bhs[needblocks + 1];
		struct buffer_head **bhs;
		int curbh, curpage;

		if (block_size > deflateBound(1UL << zisofs_block_shift)) {
		@@ -80,7 +81,11 @@ static loff_t zisofs_uncompress_block(struct inode *inode, loff_t block_start,

		/* Because zlib is not thread-safe, do all the I/O at the top. */
		blocknum = block_start >> bufshift;
		memset(bhs, 0, (needblocks + 1) * sizeof(struct buffer_head *));
		bhs = kcalloc(needblocks + 1, sizeof(*bhs), GFP_KERNEL);
		if (!bhs) {
		*errp = -ENOMEM;
		return 0;
		}
		haveblocks = isofs_get_blocks(inode, blocknum, bhs, needblocks);
		ll_rw_block(REQ_OP_READ, 0, haveblocks, bhs);

		@@ -190,6 +195,7 @@ z_eio:
		b_eio:
		for (i = 0; i < haveblocks; i++)
		brelse(bhs[i]);
		kfree(bhs);
		return stream.total_out;
		}

		@@ -305,7 +311,7 @@ static int zisofs_readpage(struct file file, struct page page)
		unsigned int zisofs_pages_per_cblock =
		PAGE_SHIFT <= zisofs_block_shift ?
		(1 << (zisofs_block_shift - PAGE_SHIFT)) : 0;
		struct page *pages[max_t(unsigned, zisofs_pages_per_cblock, 1)];
		struct page **pages;
		pgoff_t index = page->index, end_index;

		end_index = (inode->i_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
		@@ -330,6 +336,12 @@ static int zisofs_readpage(struct file file, struct page page)
		full_page = 0;
		pcount = 1;
		}
		pages = kcalloc(max_t(unsigned int, zisofs_pages_per_cblock, 1),
		sizeof(*pages), GFP_KERNEL);
		if (!pages) {
		unlock_page(page);
		return -ENOMEM;
		}
		pages[full_page] = page;

		for (i = 0; i < pcount; i++, index++) {
		@@ -357,6 +369,7 @@ static int zisofs_readpage(struct file file, struct page page)
		}

		/* At this point, err contains 0 or -EIO depending on the "critical" page */
		kfree(pages);
		return err;
		}

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