ext4: avoid arithemetic overflow that can trigger a BUG
authorTheodore Ts'o <tytso@mit.edu>
Sat, 1 Sep 2018 16:45:04 +0000 (12:45 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 29 Sep 2018 10:06:06 +0000 (03:06 -0700)
commit779af00b3fa38d040a4798afdb2c57cc64ba346e
treeb1fc41b567f8f0ac5ea71d9e39cb6a693974e863
parent3f9eafe8772f9a86cab2e431a44bce775f6b7ba5
ext4: avoid arithemetic overflow that can trigger a BUG

commit bcd8e91f98c156f4b1ebcfacae675f9cfd962441 upstream.

A maliciously crafted file system can cause an overflow when the
results of a 64-bit calculation is stored into a 32-bit length
parameter.

https://bugzilla.kernel.org/show_bug.cgi?id=200623

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Wen Xu <wen.xu@gatech.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/ext4/ext4.h
fs/ext4/inode.c