- Use ftruncate64 instead of ftruncate to workaround seccomp
- Cast uint32_t to off64_t before making it negative
Note: Using ftruncate with a modern NDK libc should actually be
fine as the syscall wrapper in bionic will use ftruncate64 internally.
However, since we are using the libc.a from r10e built for Gingerbread,
seccomp wasn't a thing back then, and also the ftruncate64 symbol is
missing; we have to create our own wrapper and call it instead on
32-bit ABIs.
Props to @jnotuo for discovering the overflow bug and seccomp issue
Fix#3703, close#4915
- legacy devices brought up to Android 10 may now use a compressed dt in a hdr_v0 AOSP dt variant extra section, so detect, decompress and recompress this
- so far these have only been done using lz4 compression (latest format revision magic), e.g. LOS 17.1 victara (Moto X)
- some Samsung devices (e.g. Galaxy S5 SMG-900H) use a slightly different AOSP bootimg.h variant with `#define BOOT_NAME_SIZE 20` instead of 16
- since all known examples of these device images do not have anything in the NAME or CMDLINE fields, and the bootloader also accepts standard AOSP images, simply offset the SHA1/SHA256 detection by 4 bytes to avoid false positives from these images, remain an equally effective detection shortcut, and ensure a proper SHA1 checksum on repack
aosp-dtbhdt2-4offhash-seandroid-256sig-samsung_gs5-smg900h-boot.img
UNPACK CHECKSUM [00000000b11580f7d20f70297cdc31e02626def0356c82b90000000000000000]
REPACK CHECKSUM [73b18751202e56c433f89dfd1902c290eaf4eef3e167fcf03b814b59a5e984b6]
AIK CHECKSUM [b11580f7d20f70297cdc31e02626def0356c82b9000000000000000000000000]
This patch should result in a `magiskboot unpack -n boot.img; magiskboot repack boot.img` new-boot.img matching the AIK CHECKSUM above.
- support unpack without decompression to allow easy testing of magiskboot's header, structure and hashing handling by comparing repack checksum versus origbootimg
- make -n first to match repack
