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2017-02-22Only merge acquire items with the same meta keyJulian Andres Klode
Since the introduction of by-hash, two differently named files might have the same real URL. In our case, the files icons-64x64.tar.gz and icons-128x128.tar.gz of empty tarballs. APT would try to merge them and end with weird errors because it completed the first download and enters the second stage for decompressing and verifying. After that it would queue a new item to copy the original file to the location, but that copy item would be in the wrong stage, causing it to use the hashes for the decompressed item. Closes: #838441 (cherry picked from commit 7b78e8bef1fc9de22d826db1db9df25f97d3710c) (cherry picked from commit d2749c845954fc1ea38133b050ee49d6f6544235)
2017-02-22remove 'old' FAILED files in the next acquire callDavid Kalnischkies
If apt renames a file to .FAILED it leaves its namespace and is never touched again – expect since 1.1~exp4 in which "apt clean" will remove those files. The usefulness of these files rapidly degrades if you don't keep the update log itself (together with debug output in the best case) through and on 99% of all system they will be kept around forever just to collect dust over time and eat up space. With this commit an update call will remove all FAILED files of previous runs, so that the FAILED files you have on disk are always only the ones related to the last apt run stopping apt from hoarding files. Closes: 846476 (cherry picked from commit 7ca83492e802967f183babf06ab541b1b51f1703) (cherry picked from commit c8540403ed35fa36e1610fd90aeae8f66c126fdb)
2017-02-22avoid validate/delete/load race in cache generationDavid Kalnischkies
Keeping the Fd of the cache file we have validated around to later load it into the mmap ensures not only that we load the same file (which wouldn't really be a problem in practice), but that this file also still exists and wasn't deleted e.g. by a 'apt clean' call run in parallel. (cherry picked from commit 06606f073210fe3902fe92d5ff77fa1ab621b972) (cherry picked from commit 2e5726edcac4fc9228c6b16281365c3ade189b8b)
2017-02-22use FindB instead of FindI for Debug::pkgAutoRemoveDavid Kalnischkies
Again no practical difference, but for consistency a boolean option should really be accessed via a boolean method rather than an int especially if you happen to try setting the option to "true" … Gbp-Dch: Ignore (cherry picked from commit c15ba854b6736696f164e4d2c243a944e2d4006e) (cherry picked from commit c0dc26456ba74da449eae11c04c3edb3b5f1e35e)
2017-02-22avoid producing invalid options if repo has no hostDavid Kalnischkies
This can happen e.g. for file: repositories. There is no inherent problem with setting such values internally, but its bad style, forbidden in the manpage and could be annoying in the future. Gbp-Dch: Ignore (cherry picked from commit 44ecb8c3579e5ae8828f83530e4151a0ff84d5d6) (cherry picked from commit fec19de5e786564ed8699b38310f7d1a7c348c01)
2017-02-22add TMP/TEMP/TEMPDIR to the TMPDIR DropPrivileges danceDavid Kalnischkies
apt tools do not really support these other variables, but tools apt calls might, so lets play save and clean those up as needed. Reported-By: Paul Wise (pabs) on IRC (cherry picked from commit e2c8c825a5470e33c25d00e07de188d0e03922c8) (cherry picked from commit 52067bd0a9e23642b7fa791fb63f4b69cafceb36)
2017-02-22reset HOME, USER(NAME), TMPDIR & SHELL in DropPrivilegesDavid Kalnischkies
We can't cleanup the environment like e.g. sudo would do as you usually want the environment to "leak" into these helpers, but some variables like HOME should really not have still the value of the root user – it could confuse the helpers (USER) and HOME isn't accessible anyhow. Closes: 842877 (cherry picked from commit 34b491e735ad47c4805e63f3b83a659b8d10262b) (cherry picked from commit cc5919076ba1c2dab773a6c06cb3dd5497f0c656)
2017-02-22keep Release.gpg on untrusted to trusted IMS-HitDavid Kalnischkies
A user relying on the deprecated behaviour of apt-get to accept a source with an unknown pubkey to install a package containing the key expects that the following 'apt-get update' causes the source to be considered as trusted, but in case the source hadn't changed in the meantime this wasn't happening: The source kept being untrusted until the Release file was changed. This only effects sources not using InRelease and only apt-get, the apt binary downright refuses this course of actions, but it is a common way of adding external sources. Closes: 838779 (cherry picked from commit 84eec207be35b8c117c430296d4c212b079c00c1) LP: #1657440 (cherry picked from commit 5605c9880f36c764baaca59328777d34645a32fa)
2016-12-08gpgv: Flush the files before checking for errorsJulian Andres Klode
This is a follow up to the previous issue where we did not check if getline() returned -1 due to an end of file or due to an error like memory allocation, treating both as end of file. Here we ensure that we also handle buffered writes correctly by flushing the files before checking for any errors in our error stack. Buffered writes themselves were introduced in 1.1.9, but the function was never called with a buffered file from inside apt until commit 46c4043d741cb2c1d54e7f5bfaa234f1b7580f6c which was first released with apt 1.2.10. The function is public, though, so fixing this is a good idea anyway. Affected: >= 1.1.9 (cherry picked from commit 6212ee84a517ed68217429022bd45c108ecf9f85) (cherry picked from commit e115da452632a024a2885fea27a6c2c5145282b1)
2016-12-08SECURITY UPDATE: gpgv: Check for errors when splitting files (CVE-2016-1252)Julian Andres Klode
This fixes a security issue where signatures of the InRelease files could be circumvented in a man-in-the-middle attack, giving attackers the ability to serve any packages they want to a system, in turn giving them root access. It turns out that getline() may not only return EINVAL as stated in the documentation - it might also return in case of an error when allocating memory. This fix not only adds a check that reading worked correctly, it also implicitly checks that all writes worked by reporting any other error that occurred inside the loop and was logged by apt. Affected: >= 0.9.8 Reported-By: Jann Horn <jannh@google.com> Thanks: Jann Horn, Google Project Zero for reporting the issue LP: #1647467 (cherry picked from commit 51be550c5c38a2e1ddfc2af50a9fab73ccf78026) (cherry picked from commit 4ef9e0837ce139b398299431ae2294882f531d8e)
2016-11-14Revert "if the FileFd failed already following calls should fail, too"Julian Andres Klode
This reverts commit 1b63558a39ee1eed7eb024cd0e164d73beb165b1. This commit caused a regression in the unit tests: The error was propagated to Close(), where we expected it to return true.
2016-11-14Use C locale instead of C.UTF-8 for protocol stringsJulian Andres Klode
The C.UTF-8 locale is not portable, so we need to use C, otherwise we crash on other systems. We can use std::locale::classic() for that, which might also be a bit cheaper than using locale("C"). (cherry picked from commit 0fb16c3e678044d6d06ba8a6199b1e96487ee0d8)
2016-11-14imbue .diff/Index parsing with C.UTF-8 as wellDavid Kalnischkies
In 3bdff17c894d0c3d0f813d358fc45d7a263f3552 we did it for the datetime parsing, but we use the same style in the parsing for pdiff (where the size of the file is in the middle of the three fields) so imbueing here as well is a good idea. (cherry picked from commit 1136a707b7792394ea4b1d039dda4f321fec9da4)
2016-11-14prevent C++ locale number formatting in text APIs (try 3)David Kalnischkies
This time it is the formatting of floating numbers in progress reporting with a radix charater potentially not being dot. Followup of 7303e11ff28f920a6277c159aa46f80c007350bb. Regression of b58e2c7c56b1416a343e81f9f80cb1f02c128e25 in so far as it exchanging very effected with slightly less effected code. LP: 1611010 (cherry picked from commit 0919f1df552ddf022ce4508cbf40e04eae5ef896)
2016-11-14prevent C++ locale number formatting in text APIs (try 2)David Kalnischkies
Followup of b58e2c7c56b1416a343e81f9f80cb1f02c128e25. Still a regression of sorts of 8b79c94af7f7cf2e5e5342294bc6e5a908cacabf. Closes: 832044 (cherry picked from commit 7303e11ff28f920a6277c159aa46f80c007350bb)
2016-11-14imbue datetime parsing with C.UTF-8 localeDavid Kalnischkies
Rewritten in 9febc2b238e1e322dce1f94ecbed46d595893b52 for c++ locales usage and rewritten again in 1d742e01470bba27715a8191c50adde4b39c2f19 to avoid a currently present stdlibc++6 bug in the std::get_time implementation. The later implementation uses still stringstreams for parsing, but forgot to explicitly reset the locale to something sane (for parsing english dates that is), so date and especially the parsing of a number is depending on the locale. Turns out, the French (among others) format their numbers with space as thousand separator so for some reason the stdlibc++6 thinks its a good idea to interpret the entire datetime string as a single number instead of realizing that in "25 Jun …" the later parts can't reasonably be part of that number even through there are spaces there… Workaround is hence: LC_NUMERIC=C.UTF-8 Closes: 828011 (cherry picked from commit 3bdff17c894d0c3d0f813d358fc45d7a263f3552)
2016-11-14avoid std::get_time usage to sidestep libstdc++6 bugDavid Kalnischkies
As reported upstream in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71556 the implementation of std::get_time is currently not as accepting as strptime is, especially in how hours should be formatted. Just reverting 9febc2b238e1e322dce1f94ecbed46d595893b52 would be possible, but then we would reopen the problems fixed by it, so instead I opted here for a rewrite of the parsing logic which makes this method a lot longer, but at least it provides the same benefits as the rewrite in std::get_time was intended to give us and decouples us from the fix of the issue in the standard library implementation of GCC. LP: 1593583 (cherry picked from commit 1d742e01470bba27715a8191c50adde4b39c2f19)
2016-11-14accept only the expected UTC timezones in date parsingDavid Kalnischkies
HTTP/1.1 hardcodes GMT (RFC 7231 §7.1.1.1) and what is good enough for the internet must be good enough for us™ as we reuse the implementation internally to parse (most) dates we encounter in various places like the Release files with their Date and Valid-Until header fields. Implementing a fully timezone aware parser just feels too hard for no effective benefit as it would take 5+ years (= until LTS's are out of fashion) until a repository could use non-UTC dates and expect it to work. Not counting non-apt implementations which might or might not only want to encounter UTC here as well. As a bonus, this eliminates the use of an instance of setlocale in libapt. Closes: 819697 (cherry picked from commit 9febc2b238e1e322dce1f94ecbed46d595893b52)
2016-11-14use de-localed std::put_time instead rolling our ownDavid Kalnischkies
(cherry picked from commit eceb219c2a64f3f81421c3c6587380b6ae81a530)
2016-10-05Do not read stderr from proxy autodetection scriptsJulian Andres Klode
This fixes a regression introduced in commit 8f858d560e3b7b475c623c4e242d1edce246025a don't leak FD in AutoProxyDetect command return parsing which accidentally made the proxy autodetection code also read the scripts output on stderr, not only on stdout when it switched the code from popen() to Popen(). Reported-By: Tim Small <tim@seoss.co.uk> (cherry picked from commit 0ecceb5bb9cc8727c117195945b7116aceb984fe)
2016-10-05VersionHash: Do not skip too long dependency linesJulian Andres Klode
If the dependency line does not contain spaces in the repository but does in the dpkg status file (because dpkg normalized the dependency list), the dpkg line might be longer than the line in the repository. If it now happens to be longer than 1024 characters, it would be skipped, causing the hashes to be out of date. Note that we have to bump the minor cache version again as this changes the format slightly, and we might get mismatches with an older src cache otherwise. Fixes Debian/apt#23 (cherry picked from commit 708e2f1fe99e6f067292bc909f03f12c181e4798)
2016-10-05try not to call memcpy with length 0 in hash calculationsDavid Kalnischkies
memcpy is marked as nonnull for its input, but ignores the input anyhow if the declared length is zero. Our SHA2 implementations do this as well, it was "just" MD5 and SHA1 missing, so we add the length check here as well as along the callstack as it is really pointless to do all these method calls for "nothing". Reported-By: gcc -fsanitize=undefined (cherry picked from commit 644478e8db56f305601c3628a74e53de048b28c8)
2016-10-05Base256ToNum: Fix uninitialized valueJulian Andres Klode
If the inner Base256ToNum() returned false, it did not set Num to a new value, causing it to be uninitialized, and thus might have caused the function to exit despite a good result. Also document why the Res = Num, if (Res != Num) magic is done. Reported-By: valgrind (cherry picked from commit cf7503d8a09ebce695423fdeb2402c456c18f3d8)
2016-10-05TagFile: Fix off-by-one errors in comment strippingJulian Andres Klode
Adding 1 to the value of d->End - current makes restLength one byte too long: If we pass memchr(current, ..., restLength) has thus undefined behavior. Also, reading the value of current has undefined behavior if current >= d->End, not only for current > d->End: Consider a string of length 1, that is d->End = d->Current + 1. We can only read at d->Current + 0, but d->Current + 1 is beyond the end of the string. This probably caused several inexplicable build failures on hurd-i386 in the past, and just now caused a build failure on Ubuntu's amd64 builder. Reported-By: valgrind (cherry picked from commit 923c592ceb6014b31ec751b97b3ed659fa3e88ae)
2016-10-05Fix segfault and out-of-bounds read in Binary fieldsJulian Andres Klode
If a Binary field contains one or more spaces before a comma, the code produced a segmentation fault, as it accidentally set a pointer to 0 instead of the value of the pointer. If the comma is at the beginning of the field, the code would create a binStartNext that points one element before the start of the string, which is undefined behavior. We also need to check that we do not exit the string during the replacement of spaces before commas: A string of the form " ," would normally exit the boundary of the Buffer: binStartNext = offset 1 ',' binEnd = offset 0 ' ' isspace_ascii(*binEnd) = true => --binEnd => binEnd = - 1 We get rid of the problem by only allowing spaces to be eliminated if they are not the first character of the buffer: binStartNext = offset 1 ',' binEnd = offset 0 ' ' binEnd > buffer = false, isspace_ascii(*binEnd) = true => exit loop => binEnd remains 0 (cherry picked from commit ce6cd75dc367b92f65e4fb539dd166d0f3361f8c)
2016-10-05don't loop on pinning pkgs from absolute debs by regexDavid Kalnischkies
An absolute filename for a *.deb file starts with a /. A package with the name of the file is inserted in the cache which is provided by the "real" package for internal reasons. The pinning code detects a regex based wildcard by having the regex start with /. That is no problem as a / can not be included in a package name… expect that our virtual filename package can and does. We fix this two ways actually: First, a regex is only being considered a regex if it also ends with / (we don't support flags). That stops our problem with the virtual filename packages already, but to be sure we also do not enter the loop if matcher and package name are equal. It has to be noted that the creation of pins for virtual packages like the here effected filename packages is pointless as only versions can be pinned, but checking that a package is really purely virtual is too costly compared to just creating an unused pin. Closes: 835818 (cherry picked from commit e950b7e2f89b5e48192cd469c963a44fff9f1450)
2016-10-05changelog: Respect Dir setting for local changelog gettingJulian Andres Klode
This fixes issues with chroots, but the goal here was to get the test suite working on systems without dpkg. (cherry picked from commit 2ed62ba6abcad809d1898a40950f86217af73812)
2016-10-05install-progress: Call the real ::fork() in our fork() methodJulian Andres Klode
We basically called ourselves before, creating an endless loop. Reported-By: clang (cherry picked from commit d651c4cd71a43c385c3d3bcd3a9f25bf0a67f8f2)
2016-10-05Ignore SIGINT and SIGQUIT for Pre-Install hooksJulian Andres Klode
Instead of erroring out when receiving a SIGINT, let the child deal with it - we'll error out anyway if the child exits with an error or due to the signal. Also ignore SIGQUIT, as system() ignores it. This basically fixes Bug #832593, but: we are running the hooks via sh -c. Some shells exit with a signal error even if the command they are executing catches the signal and exits successfully. So far, this has been noticed on dash, which unfortunately, is our default shell. Example: $ cat trap.sh trap 'echo int' INT; sleep 10; exit 0 $ if dash -c ./trap.sh; then echo OK: $?; else echo FAIL: $?; fi ^Cint FAIL: 130 $ if mksh -c ./trap.sh; then echo OK: $?; else echo FAIL: $?; fi ^Cint OK: 0 $ if bash -c ./trap.sh; then echo OK: $?; else echo FAIL: $?; fi ^Cint OK: 0 (cherry picked from commit a6ae3d3df490e7a5a1c8324ba9dc2e63972b1529)
2016-10-05set the correct item FileSize in by-hash caseDavid Kalnischkies
In af81ab9030229b4ce6cbe28f0f0831d4896fda01 we implement by-hash as a special compression type, which breaks this filesize setting as the code is looking for a foobar.by-hash file then. Dealing this slightly gets us the intended value. Note that this has no direct effect as this value will be set in other ways, too, and could only effect progress reporting. Gbp-Dch: Ignore (cherry picked from commit 3084ef2292642d43e533654354a4929abe55d91b)
2016-10-05drop incorrect const attribute from DirectoryExistsDavid Kalnischkies
Since its existence in 2010 DirectoryExists was always marked with this attribute, but for no real reason. Arguably a check for the existence of the file is not modifying global state, so theoretically this shouldn't be a problem. It is wrong from a logical point of view through as between two calls the directory could be created so the promise we made to the compiler that it could remove the second call would be wrong, so API wise it is wrong. It's a bit mysterious that this is only observeable on ppc64el and can be fixed by reordering code ever so slightly, but in the end its more our fault for adding this attribute than the compilers fault for doing something silly based on the attribute. LP: 1473674 (cherry picked from commit 9445fa62386c80c9822e77484d30b2109aa0f2dc)
2016-10-05fileutl: empty file support: Avoid fstat() on -1 fd and check resultJulian Andres Klode
When checking if a file is empty, we forget to check that fstat() actually worked. (cherry picked from commit 15fe8e62d37bc87114c59d385bed7ceefb72886b)
2016-10-05allow user@host (aka: no password) in URI parsingDavid Kalnischkies
If the URI had no password the username was ignored (cherry picked from commit a1f3ac8aba0675321dd46d074af8abcbb10c19fd)
2016-10-05pass --force-remove-essential to dpkg only if neededDavid Kalnischkies
APT (usually) knows which package is essential or not, so we can avoid passing this force flag to dpkg unconditionally if the user hasn't chosen a non-default essential handling obscuring the information. (cherry picked from commit d3930f8716f439c229cd3d11813823d847a2ecff)
2016-10-05gpgv: Unlink the correct temp file in error caseJulian Andres Klode
Previously, when data could be created and sig not, we would unlink sig, not data (and vice versa). (cherry picked from commit d0d06f44ed60a3888528d834a799bae86c2978d5)
2016-10-05if the FileFd failed already following calls should fail, tooDavid Kalnischkies
There is no point in trying to perform Write/Read on a FileFd which already failed as they aren't going to work as expected, so we should make sure that they fail early on and hard. (cherry picked from commit 02c38073af51802c02bb104d4450e0e112d641ad)
2016-10-05(error) va_list 'args' was opened but not closed by va_end()David Kalnischkies
Reported-By: cppcheck Gbp-Dch: Ignore (cherry picked from commit 196d590a99e309764e07c9dc23ea98897eebf53a)
2016-08-31rred: truncate result file before writing to itDavid Kalnischkies
If another file in the transaction fails and hence dooms the transaction we can end in a situation in which a -patched file (= rred writes the result of the patching to it) remains in the partial/ directory. The next apt call will perform the rred patching again and write its result again to the -patched file, but instead of starting with an empty file as intended it will override the content previously in the file which has the same result if the new content happens to be longer than the old content, but if it isn't parts of the old content remain in the file which will pass verification as the new content written to it matches the hashes and if the entire transaction passes the file will be moved the lists/ directory where it might or might not trigger errors depending on if the old content which remained forms a valid file together with the new content. This has no real security implications as no untrusted data is involved: The old content consists of a base file which passed verification and a bunch of patches which all passed multiple verifications as well, so the old content isn't controllable by an attacker and the new one isn't either (as the new content alone passes verification). So the best an attacker can do is letting the user run into the same issue as in the report. Closes: #831762 (cherry picked from commit 0e071dfe205ad21d8b929b4bb8164b008dc7c474)
2016-08-31verify hash of input file in rredDavid Kalnischkies
We read the entire input file we want to patch anyhow, so we can also calculate the hash for that file and compare it with what he had expected it to be. Note that this isn't really a security improvement as a) the file we patch is trusted & b) if the input is incorrect, the result will hardly be matching, so this is just for failing slightly earlier with a more relevant error message (althrough, in terms of rred its ignored and complete download attempt instead). (cherry picked from commit 6e71ec6fcdcaa926c98fa58cd4af38e42556df15)
2016-08-31call flush on the wrapped writebuffered FileFdDavid Kalnischkies
The flush call is a no-op in most FileFd implementations so this isn't as critical as it might sound as the only non-trivial implementation is in the buffered writer, which tends not be used to buffer another buffer… (cherry picked from commit 8ca481e8419c19b6ef9074b68cc028177a507161)
2016-08-31report all instead of first error up the acquire chainDavid Kalnischkies
If we don't give a specific error to report up it is likely that all error currently in the error stack are equally important, so reporting just one could turn out to be confusing e.g. if name resolution failed in a SRV record list. (cherry picked from commit b50dfa6b2dd2d459e0c2746ac9367982b96ffac0)
2016-08-31don't change owner/perms/times through file:// symlinksDavid Kalnischkies
If we have files in partial/ from a previous invocation or similar such those could be symlinks created by file:// sources. The code is expecting only real files through and happily changes owner, modification times and permission on the file the symlink points to which tend to be files we have no business in touching in this way. Permissions of symlinks shouldn't be changed, changing owner is usually pointless to, but just to be sure we pick the easy way out and use lchown, check for symlinks before chmod/utimes. Reported-By: Mattia Rizzolo on IRC (cherry picked from commit 3465138575e1fd0d5892d9b6be1ae232eb873460)
2016-08-31do not treat same-version local debs as downgradeDavid Kalnischkies
As the volatile sources are parsed last they were sorted behind the dpkg/status file and hence are treated as a downgrade, which isn't really what you want to happen as from a user POV its an upgrade. (cherry picked from commit cb9ac09bd6a36e73c2dce1d529acde6e4d15e32d)
2016-08-31reinstalling local deb file is no downgradeDavid Kalnischkies
If we have a (e.g. locally built) deb file installed and do try to install it again apt complained about this being a downgrade, but it wasn't as it is the very same version… it was just confused into not merging the versions together which looks like a downgrade then. The same size assumption is usually good, but given that volatile files are parsed last (even after the status file) the base assumption no longer holds, but is easy to adept without actually changing anything in practice. (cherry picked from commit e7edb2fef8370d54a4b8e5a01266e6eda81ef84e)
2016-08-31protect only the latest same-source providers from autoremoveDavid Kalnischkies
Traditionally all providers are protected providing something as apt can't know which of them is actually really providing the functionality for the user ensuring that we don't propose the removal of used stuff, but that is of course also keeping stuff around which could be removed. That can cause the collection of multiple old providers until the provided package is itself no longer needed (e.g. out-of-tree kernel modules). We combat this by marking providers only from the newest source package version so that old providers built by older versions of the same source package can be garbage collected. (cherry picked from commit a0ed43f7323b9d7976ed0ba8d437a42e24af9eaf)
2016-08-31more explicit MarkRequired algorithm code (part 2)David Kalnischkies
As the previous commit, this shouldn't change behavior at all, but beside being more explicit and perhaps faster its also considerably shorter (granted, mostly by if0-block elimination). Gbp-Dch: Ignore (cherry picked from commit 5a3339db48479114a0e1e11ebc8d640eb3e49933)
2016-08-31more explicit MarkRequired algorithm codeDavid Kalnischkies
Piling everything in a single if statement always made my head wobble, but it hasn't even a benefit as the most common case of a package which isn't installed passes all of the old if and lands in the non-existent else-part of the inner if. So beside a subjective cleanup of what goes on this implementation should also be a bit faster. No change in behavior should be present. Gbp-Dch: Ignore (cherry picked from commit 769e9f3ea1cbe67d3b98e6db6c956abde2384868)
2016-08-31factor out Pkg/DepIterator prettyprinters into own headerDavid Kalnischkies
The old prettyprinters have only access to the struct they pretty print, which isn't enough usually as we want to know for a package also a bit of state information like which version is the candidate. We therefore need to pull the DepCache into context and hence use a temporary struct which is printed instead of the iterator itself. (cherry picked from commit 84573326f41dd09b914b8374548e7ee7c93d0439)
2016-08-31write auto-bits before calling dpkg & again after if neededDavid Kalnischkies
Writing first means that even in the event of a power-failure the autobit is saved for future processing instead of "forgotten" so that the package is treated as manually installed. In some cases we have to re-run the writing after dpkg is done through as dpkg can let packages disappear and in such cases apt will move autobits around (or in that case non-autobits) which we need to store. (cherry picked from commit 309f497b7280a45e3626493318adb6d39ba5c69b)
2016-08-31if reading of autobit state failed, let write failDavid Kalnischkies
If we can't read the old file we can't just move forward as that would discard potentially discard old data (especially other fields). We let it fail only after we are done writing the new file so a user has the chance to look into and merge the new data (which is otherwise discarded). (cherry picked from commit 520931867ee2fac8415a624204414d3b62550996)