[Bug] MagiskBoot: Illegal instruction error when repacking LZMA boot image on armeabi-v7a

[MLXProjects]

Device: Samsung Galaxy Fame
Android version: 7.1.2 (doesn't matter for this case)
Magisk version name: 30.7 (Run #6047 from CI)
Magisk version code: 30700

Issue description

I'm working in a script that uses MagiskBoot on recovery to modify the installed boot image.
While unpacking works fine, repacking crashes with "Illegal instruction" since Magisk v30.1 (unlike #9550 where v30.2 worked).
v30.0 and earlier works, and this coincides with the migration to lzma-rust2 (while not sure if directly related).
This issue is like #9660 and #9550 but the other way around (unpack works, repack fails).
Funnily enough, the output boot.img (attached as boot-output.img.gz) is truncated and at the end it contains "LZMA data is corrupt". This is not a log, it's just a coincidence since the original (uploaded as boot.img.gz) contains it too; I just found it curious enough to point it out.

Some debugging

I've used GDB on the debug binary and symbols to give a proper backtrace, I don't know Rust but it may help finding the issue.

/tmp/boot # /tmp/gdb --symbols=/tmp/magiskboot.dbg --exec=/tmp/magiskboot -ex  'set args repack /dev/block/mmcblk0p5 ./boot.img'
/tmp/gdb: warning: Couldn't determine a path for the index cache directory.
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Reading symbols from /tmp/magiskboot.dbg...
(gdb) r
Starting program: /tmp/magiskboot repack /dev/block/mmcblk0p5 ./boot.img
Parsing boot image: [/dev/block/mmcblk0p5]
HEADER_VER      [0]
KERNEL_SZ       [3100276]
RAMDISK_SZ      [702560]
SECOND_SZ       [0]
EXTRA_SZ        [0]
PAGESIZE        [4096]
NAME            []
CMDLINE         [console=ttyS1,115200n8 mem=456M androidboot.console=ttyS1 gpt v3d_mem=67108864 pmem=24M@0x9E800000]
CHECKSUM        [2383a82055e1f874fba002704f093facbc06750f000000000000000000000000]
ZIMAGE_KERNEL
KERNEL_FMT      [lzma]
RAMDISK_FMT     [gzip]
Repack to boot image: [./boot.img]

Program received signal SIGILL, Illegal instruction.
0x000c1f40 in <alloc::raw_vec::RawVecInner>::with_capacity_zeroed_in ()
(gdb) bt
#0  0x000c1f40 in <alloc::raw_vec::RawVecInner>::with_capacity_zeroed_in ()
#1  0x000c1d70 in alloc::vec::from_elem::<i32> ()
#2  0x000bf75c in <lzma_rust2::lz::bt4::Bt4>::new ()
#3  0x000bf1ac in <lzma_rust2::lz::lz_encoder::LzEncoder>::new_bt4 ()
#4  0x000c4f2c in <lzma_rust2::enc::encoder::LzmaEncoder>::new ()
#5  0x0006dc26 in <lzma_rust2::enc::lzma_writer::LzmaWriter<&mut std::fs::File>>::new ()
#6  0x0003a352 in magiskboot::compress::compress_bytes ()
#7  0x00037f38 in cxxbridge1$189$compress_bytes ()
#8  0x00032184 in compress_bytes (format=FileFormat::LZMA, out_fd=3,
    in_bytes=...) at src/boot/boot-rs.cpp:202
#9  compress_len (type=FileFormat::CHROMEOS, in=..., fd=3)
    at src/boot/bootimg.cpp:29
#10 0x00031500 in repack (src_img=..., out_img=..., skip_comp=false)
    at src/boot/bootimg.cpp:778
#11 0x00050d06 in main ()
(gdb)

boot.img.gz
boot-output.img.gz