git/t/t5303-pack-corruption-resilience.sh
Jeff King 18f60f2d3d t5303: use printf to generate delta bases
The exact byte count of the delta base file is important.
The test-delta helper will feed it to patch_delta(), which
will barf if it doesn't match the size byte given in the
delta. Using "echo" may end up with unexpected line endings
on some platforms (e.g,. "\r\n" instead of just "\n").

This actually wouldn't cause the test to fail (since we
already expect test-delta to complain about these bogus
deltas), but would mean that we're not exercising the code
we think we are.

Let's use printf instead (which we already trust to give us
byte-perfect output when we generate the deltas).

While we're here, let's tighten the 5-byte result size used
in the "truncated copy parameters" test. This just needs to
have enough room to attempt to parse the bogus copy command,
meaning 2 is sufficient. Using 5 was arbitrary and just
copied from the base size; since those no longer match, it's
simply confusing. Let's use a more meaningful number.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-30 13:15:13 -07:00

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#!/bin/sh
#
# Copyright (c) 2008 Nicolas Pitre
#
test_description='resilience to pack corruptions with redundant objects'
. ./test-lib.sh
# Note: the test objects are created with knowledge of their pack encoding
# to ensure good code path coverage, and to facilitate direct alteration
# later on. The assumed characteristics are:
#
# 1) blob_2 is a delta with blob_1 for base and blob_3 is a delta with blob2
# for base, such that blob_3 delta depth is 2;
#
# 2) the bulk of object data is uncompressible so the text part remains
# visible;
#
# 3) object header is always 2 bytes.
create_test_files() {
test-tool genrandom "foo" 2000 > file_1 &&
test-tool genrandom "foo" 1800 > file_2 &&
test-tool genrandom "foo" 1800 > file_3 &&
echo " base " >> file_1 &&
echo " delta1 " >> file_2 &&
echo " delta delta2 " >> file_3 &&
test-tool genrandom "bar" 150 >> file_2 &&
test-tool genrandom "baz" 100 >> file_3
}
create_new_pack() {
rm -rf .git &&
git init &&
blob_1=$(git hash-object -t blob -w file_1) &&
blob_2=$(git hash-object -t blob -w file_2) &&
blob_3=$(git hash-object -t blob -w file_3) &&
pack=$(printf "$blob_1\n$blob_2\n$blob_3\n" |
git pack-objects $@ .git/objects/pack/pack) &&
pack=".git/objects/pack/pack-${pack}" &&
git verify-pack -v ${pack}.pack
}
do_repack() {
pack=$(printf "$blob_1\n$blob_2\n$blob_3\n" |
git pack-objects $@ .git/objects/pack/pack) &&
pack=".git/objects/pack/pack-${pack}"
}
do_corrupt_object() {
ofs=$(git show-index < ${pack}.idx | grep $1 | cut -f1 -d" ") &&
ofs=$(($ofs + $2)) &&
chmod +w ${pack}.pack &&
dd of=${pack}.pack bs=1 conv=notrunc seek=$ofs &&
test_must_fail git verify-pack ${pack}.pack
}
printf '\0' > zero
test_expect_success \
'initial setup validation' \
'create_test_files &&
create_new_pack &&
git prune-packed &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'create corruption in header of first object' \
'do_corrupt_object $blob_1 0 < zero &&
test_must_fail git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_1 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and loose copy of first delta allows for partial recovery' \
'git prune-packed &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
test_must_fail git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'create corruption in data of first object' \
'create_new_pack &&
git prune-packed &&
chmod +w ${pack}.pack &&
perl -i.bak -pe "s/ base /abcdef/" ${pack}.pack &&
test_must_fail git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_1 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and loose copy of second object allows for partial recovery' \
'git prune-packed &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
test_must_fail git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'create corruption in header of first delta' \
'create_new_pack &&
git prune-packed &&
do_corrupt_object $blob_2 0 < zero &&
git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and then a repack "clears" the corruption' \
'do_repack &&
git prune-packed &&
git verify-pack ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'create corruption in data of first delta' \
'create_new_pack &&
git prune-packed &&
chmod +w ${pack}.pack &&
perl -i.bak -pe "s/ delta1 /abcdefgh/" ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and then a repack "clears" the corruption' \
'do_repack &&
git prune-packed &&
git verify-pack ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'corruption in delta base reference of first delta (OBJ_REF_DELTA)' \
'create_new_pack &&
git prune-packed &&
do_corrupt_object $blob_2 2 < zero &&
git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and then a repack "clears" the corruption' \
'do_repack &&
git prune-packed &&
git verify-pack ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'corruption #0 in delta base reference of first delta (OBJ_OFS_DELTA)' \
'create_new_pack --delta-base-offset &&
git prune-packed &&
do_corrupt_object $blob_2 2 < zero &&
git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and then a repack "clears" the corruption' \
'do_repack --delta-base-offset &&
git prune-packed &&
git verify-pack ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'corruption #1 in delta base reference of first delta (OBJ_OFS_DELTA)' \
'create_new_pack --delta-base-offset &&
git prune-packed &&
printf "\001" | do_corrupt_object $blob_2 2 &&
git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_2 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and then a repack "clears" the corruption' \
'do_repack --delta-base-offset &&
git prune-packed &&
git verify-pack ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and a redundant pack allows for full recovery too' \
'do_corrupt_object $blob_2 2 < zero &&
git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null &&
mv ${pack}.idx tmp &&
git hash-object -t blob -w file_1 &&
git hash-object -t blob -w file_2 &&
printf "$blob_1\n$blob_2\n" | git pack-objects .git/objects/pack/pack &&
git prune-packed &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'corruption of delta base reference pointing to wrong object' \
'create_new_pack --delta-base-offset &&
git prune-packed &&
printf "\220\033" | do_corrupt_object $blob_3 2 &&
git cat-file blob $blob_1 >/dev/null &&
git cat-file blob $blob_2 >/dev/null &&
test_must_fail git cat-file blob $blob_3 >/dev/null'
test_expect_success \
'... but having a loose copy allows for full recovery' \
'mv ${pack}.idx tmp &&
git hash-object -t blob -w file_3 &&
mv tmp ${pack}.idx &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'... and then a repack "clears" the corruption' \
'do_repack --delta-base-offset --no-reuse-delta &&
git prune-packed &&
git verify-pack ${pack}.pack &&
git cat-file blob $blob_1 > /dev/null &&
git cat-file blob $blob_2 > /dev/null &&
git cat-file blob $blob_3 > /dev/null'
test_expect_success \
'corrupting header to have too small output buffer fails unpack' \
'create_new_pack &&
git prune-packed &&
printf "\262\001" | do_corrupt_object $blob_1 0 &&
test_must_fail git cat-file blob $blob_1 > /dev/null &&
test_must_fail git cat-file blob $blob_2 > /dev/null &&
test_must_fail git cat-file blob $blob_3 > /dev/null'
# \0 - empty base
# \1 - one byte in result
# \1 - one literal byte (X)
test_expect_success \
'apply good minimal delta' \
'printf "\0\1\1X" > minimal_delta &&
test-tool delta -p /dev/null minimal_delta /dev/null'
# \0 - empty base
# \1 - 1 byte in result
# \2 - two literal bytes (one too many)
test_expect_success \
'apply delta with too many literal bytes' \
'printf "\0\1\2XX" > too_big_literal &&
test_must_fail test-tool delta -p /dev/null too_big_literal /dev/null'
# \4 - four bytes in base
# \1 - one byte in result
# \221 - copy, one byte offset, one byte size
# \0 - copy from offset 0
# \2 - copy two bytes (one too many)
test_expect_success \
'apply delta with too many copied bytes' \
'printf "\4\1\221\0\2" > too_big_copy &&
printf base >base &&
test_must_fail test-tool delta -p base too_big_copy /dev/null'
# \0 - empty base
# \2 - two bytes in result
# \2 - two literal bytes (we are short one)
test_expect_success \
'apply delta with too few literal bytes' \
'printf "\0\2\2X" > truncated_delta &&
test_must_fail test-tool delta -p /dev/null truncated_delta /dev/null'
# \0 - empty base
# \1 - one byte in result
# \221 - copy, one byte offset, one byte size
# \0 - copy from offset 0
# \1 - copy one byte (we are short one)
test_expect_success \
'apply delta with too few bytes in base' \
'printf "\0\1\221\0\1" > truncated_base &&
test_must_fail test-tool delta -p /dev/null truncated_base /dev/null'
# \4 - four bytes in base
# \2 - two bytes in result
# \1 - one literal byte (X)
# \221 - copy, one byte offset, one byte size
# (offset/size missing)
#
# Note that the literal byte is necessary to get past the uninteresting minimum
# delta size check.
test_expect_success \
'apply delta with truncated copy parameters' \
'printf "\4\2\1X\221" > truncated_copy_delta &&
printf base >base &&
test_must_fail test-tool delta -p base truncated_copy_delta /dev/null'
# \0 - empty base
# \1 - one byte in result
# \1 - one literal byte (X)
# \1 - trailing garbage command
test_expect_success \
'apply delta with trailing garbage literal' \
'printf "\0\1\1X\1" > tail_garbage_literal &&
test_must_fail test-tool delta -p /dev/null tail_garbage_literal /dev/null'
# \4 - four bytes in base
# \1 - one byte in result
# \1 - one literal byte (X)
# \221 - copy, one byte offset, one byte size
# \0 - copy from offset 0
# \1 - copy 1 byte
test_expect_success \
'apply delta with trailing garbage copy' \
'printf "\4\1\1X\221\0\1" > tail_garbage_copy &&
printf base >base &&
test_must_fail test-tool delta -p /dev/null tail_garbage_copy /dev/null'
# \0 - empty base
# \1 - one byte in result
# \1 - one literal byte (X)
# \0 - bogus opcode
test_expect_success \
'apply delta with trailing garbage opcode' \
'printf "\0\1\1X\0" > tail_garbage_opcode &&
test_must_fail test-tool delta -p /dev/null tail_garbage_opcode /dev/null'
test_done