tree 20c5c1376f4b5a1793a729bc23828e74f8387c7d
parent 755eb6b6069efb3edbbaa335899d34369ddea83a
author Tom Cherry <tomcherry@google.com> 1592329724 +0000
committer Randall Huang <huangrandall@google.com> 1592350359 +0000

fsmgr: fix integer overflow in fs_mgr

As the EXT4_MAX_BLOCK_SIZE defined as 65536 which reached maxium value
of unsigned int. The superblock value maybe larger than 65536. This is
found by the Integer Overflow Sanitizer.

This patch fixed below boot error when userdata is corrupted:
init: processing action (fs) from
(/vendor/etc/init/hw/init.freescale.rc:221)
init: [libfs_mgr]Invalid ext4 superblock on '/dev/block/by-name/userdata'
init: InitFatalReboot: signal 6 init: #00 pc 00000000000af7e8  /system/bin/init
(android::init::InitFatalReboot(int)+208) init: #01 pc 00000000000afbd0  /system/bin/init
(android::init::InstallRebootSignalHandlers()::$_22::__invoke(int)+32)
init: #02 pc 00000000000006bc  [vdso:0000ffff9691b000] (__kernel_rt_sigreturn)
init: #03 pc 000000000004e070  /system/lib64/bootstrap/libc.so (abort+176)
init: #04 pc 000000000003427c  /system/lib64/libfs_mgr.so
(read_ext4_superblock(std::__1::basic_string<char, std::__1::char_
traits<char>, std::__1::allocator<char> > const&,
android::fs_mgr::FstabEntry const&, ext4_super_block*, int*)+1804)

Test: boot with corrupted ext4 superblock
Bug: 156200421

Signed-off-by: Haoran.Wang <elven.wang@nxp.com>
Change-Id: Ib1b69bf4623f69696cb637b226ec3359fc2ed409
(cherry picked from commit cb472b92e54ba1647c02397565958322f0d74929)