Initial remote commit

2026-04-30 11:04:05 +00:00
commit b86e4f9a98
103 changed files with 262770 additions and 0 deletions
--- a/test/patch5.sh
+++ b/test/patch5.sh
@@ -0,0 +1,76 @@
+pip install crcmod --break-system-packages -q
+
+python3 -c "
+import struct, crcmod
+
+crc32c = crcmod.predefined.mkCrcFun('crc-32c')
+
+with open('/dev/nbd0','rb') as f:
+    f.seek(1024)
+    sb = f.read(1024)
+
+uuid      = sb[104:120]
+csum_seed = struct.unpack_from('<I', sb, 408)[0]
+BSIZE     = 4096
+
+def compute_bitmap_csum(bitmap_data):
+    return crc32c(uuid + bitmap_data, csum_seed) & 0xFFFF
+
+def compute_gdt_csum(g, entry):
+    e = bytearray(entry)
+    struct.pack_into('<H', e, 30, 0)
+    return crc32c(uuid + struct.pack('<H', g) + bytes(e), csum_seed) & 0xFFFF
+
+data = bytearray(open('/tmp/merged_gdt.bin','rb').read())
+
+print('Fixing groups 0-12 only (zeroed by fast initialization)...')
+with open('/dev/nbd0','rb') as f:
+    for g in range(13):
+        e = data[g*64:(g+1)*64]
+
+        # Read actual inode bitmap (will be zeros for damaged groups)
+        ib_block = struct.unpack_from('<I', e, 4)[0]
+        f.seek(ib_block * BSIZE)
+        ib_data = f.read(BSIZE)
+
+        # Read actual block bitmap
+        bb_block = struct.unpack_from('<I', e, 0)[0]
+        f.seek(bb_block * BSIZE)
+        bb_data = f.read(BSIZE)
+
+        # Compute correct checksums from actual bitmap data
+        ib_csum = compute_bitmap_csum(ib_data)
+        bb_csum = compute_bitmap_csum(bb_data)
+
+        struct.pack_into('<H', data, g*64+26, ib_csum)  # ib_csum_lo
+        struct.pack_into('<H', data, g*64+50, 0)        # ib_csum_hi
+        struct.pack_into('<H', data, g*64+24, bb_csum)  # bb_csum_lo
+        struct.pack_into('<H', data, g*64+48, 0)        # bb_csum_hi
+
+        # Recompute GDT entry checksum
+        gdt_csum = compute_gdt_csum(g, data[g*64:(g+1)*64])
+        struct.pack_into('<H', data, g*64+30, gdt_csum)
+
+        print(f'  Group {g:2d}: ib_csum=0x{ib_csum:04x} '
+              f'bb_csum=0x{bb_csum:04x} gdt_csum=0x{gdt_csum:04x}')
+
+with open('/tmp/merged_gdt.bin','wb') as f:
+    f.write(data)
+print('Saved')
+"
+
+pkill -f nbd_server
+nbd-client -d /dev/nbd0 2>/dev/null
+sleep 1
+python3 nbd_server_v9.py &
+sleep 2
+nbd-client 127.0.0.1 10809 /dev/nbd0 -N ""
+
+e2fsck -n /dev/nbd0 2>&1 | head -10
+
+ext4magic /dev/nbd0 \
+  -s 4096 -n 32768 \
+  -M \
+  -a $(date -d "2023-01-01" +%s) \
+  -d /mnt/recovered \
+  2>&1 | tee /tmp/ext4magic.log