Commit 40e261b89b (lib/LzmaEnc: Validate "len" before subtracting)
ensures that the variable len is at least 2. As a result, GetLenToPosState(len)
never returns a value greater than or equal to kNumLenToPosStates,
making the changes introduced in the commit 16c0dbf4bc (lzma: Make
sure we don't dereference past array) unreachable and no longer necessary.
This reverts commit 16c0dbf4bc (lzma: Make sure we don't dereference past array).
Fixes: CID 481982
Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
In LzmaEnc_CodeOneBlock(), both GetOptimumFast() and GetOptimum()
returns a value of greater or equal to 1, which is assigned to
"len". But since LZMA_MATCH_LEN_MIN == 2, "len" should be validated
before performing "len - LZMA_MATCH_LEN_MIN" to avoid underflow
when "len" equals to 1.
Fixes: CID 51508
Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Compiling under clang 10 gives:
grub-core/lib/LzmaEnc.c:1362:9: error: misleading indentation; statement is not part of the previous 'if' [-Werror,-Wmisleading-indentation]
{
^
grub-core/lib/LzmaEnc.c:1358:7: note: previous statement is here
if (repIndex == 0)
^
1 error generated.
It's not really that unclear in context: there's a commented-out
if-statement. But tweak the alignment anyway so that clang is happy.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The two dimensional array p->posSlotEncoder[4][64] is being dereferenced
using the GetLenToPosState() macro which checks if len is less than 5,
and if so subtracts 2 from it. If len = 0, that is 0 - 2 = 4294967294.
Obviously we don't want to dereference that far out so we check if the
position found is greater or equal kNumLenToPosStates (4) and bail out.
N.B.: Upstream LZMA 18.05 and later has this function completely rewritten
without any history.
Fixes: CID 51526
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Lidong Chen