Blame SOURCES/0452-io-gzio-Zero-gzio-tl-td-in-init_dynamic_block-if-huf.patch

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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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From: Daniel Axtens <dja@axtens.net>
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Date: Thu, 21 Jan 2021 12:22:28 +1100
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Subject: [PATCH] io/gzio: Zero gzio->tl/td in init_dynamic_block() if
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 huft_build() fails
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If huft_build() fails, gzio->tl or gzio->td could contain pointers that
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are no longer valid. Zero them out.
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This prevents a double free when grub_gzio_close() comes through and
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attempts to free them again.
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Signed-off-by: Daniel Axtens <dja@axtens.net>
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Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
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---
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 grub-core/io/gzio.c | 2 ++
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 1 file changed, 2 insertions(+)
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diff --git a/grub-core/io/gzio.c b/grub-core/io/gzio.c
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index f85dbae23..e9f332fbc 100644
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--- a/grub-core/io/gzio.c
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+++ b/grub-core/io/gzio.c
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@@ -1010,6 +1010,7 @@ init_dynamic_block (grub_gzio_t gzio)
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   gzio->bl = lbits;
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   if (huft_build (ll, nl, 257, cplens, cplext, &gzio->tl, &gzio->bl) != 0)
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     {
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+      gzio->tl = 0;
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       grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
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 		  "failed in building a Huffman code table");
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       return;
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@@ -1019,6 +1020,7 @@ init_dynamic_block (grub_gzio_t gzio)
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     {
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       huft_free (gzio->tl);
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       gzio->tl = 0;
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+      gzio->td = 0;
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       grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
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 		  "failed in building a Huffman code table");
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       return;