Add test case

No functional change. The large number of partitions in the test is to ensure that the code correctly handles such partition tables without a buffer overflow. Previous versions of the code did have a buffer overflow due to incorrectly computing the buffer size.
QubesOS · Dec 8, 2024 · f3a860d · f3a860d
1 parent 3fbb214
commit f3a860d
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diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
@@ -1,6 +1,7 @@
 checks:tests:
   after_script:
   - (cd qrexec-lib; gcov *.c || :)
+  - (cd gptfixer; gcov *.c || :)
   - ./ci/codecov-wrapper --gcov
   before_script:
   - sudo dnf install -y python3-pip 'pkgconfig(icu-uc)' sequoia-sqv
@@ -11,6 +12,7 @@ checks:tests:
   - python3 -m coverage run -m unittest discover -v imgconverter -p test.py
   - export CFLAGS="--coverage -DCOVERAGE" LDFLAGS=--coverage
   - make -C qrexec-lib check NO_REBUILD_TABLE=1
+  - gptfixer/test.sh
   stage: checks
   tags:
   - docker

diff --git a/gptfixer/layout b/gptfixer/layout
@@ -0,0 +1,42 @@
+label: gpt
+label-id: F4796A2A-E377-45BD-B539-D6D49E569055
+device: /dev/loop0
+unit: sectors
+first-lba: 24
+sector-size: 512
+table-length: 33
+last-lba: 41943029
+
+/dev/loop0p1 : start=32, size=409592, type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, uuid=FA4D6529-56DA-47C7-AE88-E2DFECB72621, name="EFI System"
+/dev/loop0p2 : start=411648, size=        4096, type=21686148-6449-6E6F-744E-656564454649, uuid=1E6C9DB4-1E91-46C4-846A-2030DCB13B8C, name="BIOS boot partition"
+/dev/loop0p3 : start=415744, size=        4096, type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, uuid=5DCECC9F-71B8-4357-8039-1BEBB7A48653, name="/home"
+/dev/loop0p4 : start=419840, size=        4096, type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, uuid=3EA4A03F-ACCF-4EDF-99EC-8E5F2B382459, name="/usr"
+/dev/loop0p5 : start=423944,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p6 : start=423952,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p7 : start=423960,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p8 : start=423968,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p9 : start=423976,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p10 : start=423984,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p11 : start=423992,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p12 : start=424000,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p13 : start=424008,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p14 : start=424016,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p15 : start=424024,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p16 : start=424032,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p17 : start=424040,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p18 : start=424048,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p19 : start=424056,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p20 : start=424064,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p21 : start=424072,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p22 : start=424080,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p23 : start=424088,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p24 : start=424096,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p25 : start=424104,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p26 : start=424112,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p27 : start=424120,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p28 : start=424128,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p29 : start=424136,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p30 : start=424144,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p31 : start=424152,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p32 : start=424160,size=8, type=00000000-0000-0000-0000-000000000000,uuid=00000000-0000-0000-0000-000000000000,name=""
+/dev/loop0p33 : start=424168,size=41518848,type=0FC63DAF-8483-4772-8E79-3D69D8477DE4,uuid=693244E6-3E07-47BF-AD79-ACADE4293FE7,name="Root filesystem"
diff --git a/gptfixer/test.sh b/gptfixer/test.sh
@@ -0,0 +1,38 @@
+#!/bin/bash --
+set -euo pipefail
+
+case $0 in (/*) cd "${0%/*}/";; (*/*) cd "./${0%/*}";; (*) :;; esac
+make -C .. gptfixer/gpt
+chk () {
+    loopdev=$(sudo losetup --nooverlap --find --sector-size "$1" --show -- dummy.img)
+    if [[ "$loopdev" != '/dev/loop0' ]]; then
+        printf 'Loop device is not /dev/loop0 (got %q), expect test failure\n' "$loopdev"
+    fi >&3
+    echo Dumping broken partition table
+    sudo sfdisk --label=gpt --dump -- "$loopdev"
+    sudo ./gpt fix "$loopdev"
+    echo Dumping fixed partition table
+    sudo sfdisk --label=gpt --dump -- "$loopdev"
+    sudo losetup -d "$loopdev"
+}
+
+go () (
+    set -x
+    truncate -s 0 dummy.img
+    truncate -s 20GiB dummy.img
+    sfdisk --force dummy.img < layout
+    chk 4096
+    chk 512
+)
+
+case "$#,${1-}" in
+('1,update') go 3>&2 > test.sh.stdout 2> test.sh.stderr;;
+(0,)
+    tmpdir=$(mktemp -d)
+    go 3>&2 > "$tmpdir/stdout" 2> "$tmpdir/stderr"
+    diff -u -- "$tmpdir/stdout" test.sh.stdout
+    diff -u -- "$tmpdir/stderr" test.sh.stderr
+    rm -rf -- "$tmpdir"
+;;
+(*) echo "Usage: test.sh [update]" >&2; exit 1;;
+esac
diff --git a/gptfixer/test.sh.stderr b/gptfixer/test.sh.stderr
@@ -0,0 +1,27 @@
++ truncate -s 0 dummy.img
++ truncate -s 20GiB dummy.img
++ sfdisk --force dummy.img
++ chk 4096
+++ sudo losetup --nooverlap --find --sector-size 4096 --show -- dummy.img
++ loopdev=/dev/loop0
++ [[ /dev/loop0 != \/\d\e\v\/\l\o\o\p\0 ]]
++ echo Dumping broken partition table
++ sudo sfdisk --label=gpt --dump -- /dev/loop0
+GPT PMBR size mismatch (41943039 != 5242879) will be corrected by write.
++ sudo ./gpt fix /dev/loop0
+gpt: Found GPT with different sector size, altering
++ echo Dumping fixed partition table
++ sudo sfdisk --label=gpt --dump -- /dev/loop0
++ sudo losetup -d /dev/loop0
++ chk 512
+++ sudo losetup --nooverlap --find --sector-size 512 --show -- dummy.img
++ loopdev=/dev/loop0
++ [[ /dev/loop0 != \/\d\e\v\/\l\o\o\p\0 ]]
++ echo Dumping broken partition table
++ sudo sfdisk --label=gpt --dump -- /dev/loop0
+GPT PMBR size mismatch (5242879 != 41943039) will be corrected by write.
++ sudo ./gpt fix /dev/loop0
+gpt: Found GPT with different sector size, altering
++ echo Dumping fixed partition table
++ sudo sfdisk --label=gpt --dump -- /dev/loop0
++ sudo losetup -d /dev/loop0