From 2d3862d26e67a59340ba1cf1748196c76c5787de Mon Sep 17 00:00:00 2001
From: Yinghai Lu <yinghai@kernel.org>
Date: Wed, 9 Sep 2015 15:39:12 -0700
Subject: lib/decompressors: use real out buf size for gunzip with kernel
When loading x86 64bit kernel above 4GiB with patched grub2, got kernel
gunzip error.
| early console in decompress_kernel
| decompress_kernel:
| input: [0x807f2143b4-0x807ff61aee]
| output: [0x807cc00000-0x807f3ea29b] 0x027ea29c: output_len
| boot via startup_64
| KASLR using RDTSC...
| new output: [0x46fe000000-0x470138cfff] 0x0338d000: output_run_size
| decompress: [0x46fe000000-0x47007ea29b] <=== [0x807f2143b4-0x807ff61aee]
|
| Decompressing Linux... gz...
|
| uncompression error
|
| -- System halted
the new buffer is at 0x46fe000000ULL, decompressor_gzip is using
0xffffffb901ffffff as out_len. gunzip in lib/zlib_inflate/inflate.c cap
that len to 0x01ffffff and decompress fails later.
We could hit this problem with crashkernel booting that uses kexec loading
kernel above 4GiB.
We have decompress_* support:
1. inbuf[]/outbuf[] for kernel preboot.
2. inbuf[]/flush() for initramfs
3. fill()/flush() for initrd.
This bug only affect kernel preboot path that use outbuf[].
Add __decompress and take real out_buf_len for gunzip instead of guessing
wrong buf size.
Fixes: 1431574a1c4 (lib/decompressors: fix "no limit" output buffer length)
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Jon Medhurst <tixy@linaro.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
arch/x86/boot/compressed/misc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
(limited to 'arch/x86/boot')
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index f63797942bb5..79dac1758e7c 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -448,7 +448,8 @@ asmlinkage __visible void *decompress_kernel(void *rmode, memptr heap,
#endif
debug_putstr("\nDecompressing Linux... ");
- decompress(input_data, input_len, NULL, NULL, output, NULL, error);
+ __decompress(input_data, input_len, NULL, NULL, output, output_len,
+ NULL, error);
parse_elf(output);
/*
* 32-bit always performs relocations. 64-bit relocations are only
--
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