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* usage.c: drop set_error_handle()bw/forking-and-threadingJeff King2017-05-152-10/+1
| | | | | | | | | | | | | | | | | | The set_error_handle() function was introduced by 3b331e926 (vreportf: report to arbitrary filehandles, 2015-08-11) so that run-command could send post-fork, pre-exec errors to the parent's original stderr. That use went away in 79319b194 (run-command: eliminate calls to error handling functions in child, 2017-04-19), which pushes all of the error reporting to the parent. This leaves no callers of set_error_handle(). As we're not likely to add any new ones, let's drop it. Signed-off-by: Jeff King <peff@peff.net> Acked-by: Brandon Williams <bmwill@google.com> Reviewed-by: Ramsay Jones <ramsay@ramsayjones.plus.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: restrict PATH search to executable filesBrandon Williams2017-04-252-1/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some situations run-command will incorrectly try (and fail) to execute a directory instead of an executable file. This was observed by having a directory called "ssh" in $PATH before the real ssh and trying to use ssh protoccol, reslting in the following: $ git ls-remote ssh://url fatal: cannot exec 'ssh': Permission denied It ends up being worse and run-command will even try to execute a non-executable file if it preceeds the executable version of a file on the PATH. For example, if PATH=~/bin1:~/bin2:~/bin3 and there exists a directory 'git-hello' in 'bin1', a non-executable file 'git-hello' in bin2 and an executable file 'git-hello' (which prints "Hello World!") in bin3 the following will occur: $ git hello fatal: cannot exec 'git-hello': Permission denied This is due to only checking 'access()' when locating an executable in PATH, which doesn't distinguish between files and directories. Instead use 'is_executable()' which check that the path is to a regular, executable file. Now run-command won't try to execute the directory or non-executable file 'git-hello': $ git hello Hello World! which matches what execvp(3) would have done when asked to execute git-hello with such a $PATH. Reported-by: Brian Hatfield <bhatfield@google.com> Signed-off-by: Brandon Williams <bmwill@google.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: expose is_executable functionBrandon Williams2017-04-253-42/+44
| | | | | | | | | | | Move the logic for 'is_executable()' from help.c to run_command.c and expose it so that callers from outside help.c can access the function. This is to enable run-command to be able to query if a file is executable in a future patch. Signed-off-by: Brandon Williams <bmwill@google.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: block signals between fork and execveEric Wong2017-04-201-0/+68
| | | | | | | | | | | | | | | | | | | | | | Signal handlers of the parent firing in the forked child may have unintended side effects. Rather than auditing every signal handler we have and will ever have, block signals while forking and restore default signal handlers in the child before execve. Restoring default signal handlers is required because execve does not unblock signals, it only restores default signal handlers. So we must restore them with sigprocmask before execve, leaving a window when signal handlers we control can fire in the child. Continue ignoring ignored signals, but reset the rest to defaults. Similarly, disable pthread cancellation to future-proof our code in case we start using cancellation; as cancellation is implemented with signals in glibc. Signed-off-by: Eric Wong <e@80x24.org> Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: add note about forking and threadingBrandon Williams2017-04-201-0/+9
| | | | | | | | | | | | | | | | | All non-Async-Signal-Safe functions (e.g. malloc and die) were removed between 'fork' and 'exec' in start_command in order to avoid potential deadlocking when forking while multiple threads are running. This deadlocking is possible when a thread (other than the one forking) has acquired a lock and didn't get around to releasing it before the fork. This leaves the lock in a locked state in the resulting process with no hope of it ever being released. Add a note describing this potential pitfall before the call to 'fork()' so people working in this section of the code know to only use Async-Signal-Safe functions in the child process. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: handle dup2 and close errors in childBrandon Williams2017-04-201-16/+42
| | | | | Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: eliminate calls to error handling functions in childBrandon Williams2017-04-201-32/+89
| | | | | | | | | | | | | | | All of our standard error handling paths have the potential to call malloc or take stdio locks; so we must avoid them inside the forked child. Instead, the child only writes an 8 byte struct atomically to the parent through the notification pipe to propagate an error. All user-visible error reporting happens from the parent; even avoiding functions like atexit(3) and exit(3). Helped-by: Eric Wong <e@80x24.org> Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: don't die in child when duping /dev/nullBrandon Williams2017-04-201-15/+13
| | | | | Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: prepare child environment before forkingBrandon Williams2017-04-201-10/+56
| | | | | | | | | | | In order to avoid allocation between 'fork()' and 'exec()' prepare the environment to be used in the child process prior to forking. Switch to using 'execve()' so that the construct child environment can used in the exec'd process. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* string-list: add string_list_remove functionBrandon Williams2017-04-202-0/+25
| | | | | | | | Teach string-list to be able to remove a string from a sorted 'struct string_list'. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: use the async-signal-safe execv instead of execvpBrandon Williams2017-04-201-1/+29
| | | | | | | | | | | | | | | | | | | | | Convert the function used to exec from 'execvp()' to 'execv()' as the (p) variant of exec isn't async-signal-safe and has the potential to call malloc during the path resolution it performs. Instead we simply do the path resolution ourselves during the preparation stage prior to forking. There also don't exist any portable (p) variants which also take in an environment to use in the exec'd process. This allows easy migration to using 'execve()' in a future patch. Also, as noted in [1], in the event of an ENOEXEC the (p) variants of exec will attempt to execute the command by interpreting it with the 'sh' utility. To maintain this functionality, if 'execv()' fails with ENOEXEC, start_command will atempt to execute the command by interpreting it with 'sh'. [1] http://pubs.opengroup.org/onlinepubs/009695399/functions/exec.html Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* run-command: prepare command before forkingBrandon Williams2017-04-201-20/+26
| | | | | | | | | | | | | According to [1] we need to only call async-signal-safe operations between fork and exec. Using malloc to build the argv array isn't async-signal-safe. In order to avoid allocation between 'fork()' and 'exec()' prepare the argv array used in the exec call prior to forking the process. [1] http://pubs.opengroup.org/onlinepubs/009695399/functions/fork.html Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* t0061: run_command executes scripts without a #! lineBrandon Williams2017-04-201-0/+11
| | | | | | | | | | | | | Add a test to 't0061-run-command.sh' to ensure that run_command can continue to execute scripts which don't include a '#!' line. As shell scripts are not natively executable on Windows, we use a workaround to check "#!" when running scripts from Git. As this test requires the platform (not with Git's help) to run scripts without "#!", skipt it on Windows. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* t5550: use write_script to generate post-update hookBrandon Williams2017-04-181-2/+3
| | | | | | | | | | The post-update hooks created in t5550-http-fetch-dumb.sh is missing the "!#/bin/sh" line which can cause issues with portability. Instead create the hook using the 'write_script' function which includes the proper "#!" line. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Twelfth batch for 2.13Junio C Hamano2017-04-161-0/+16
| | | | Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Merge branch 'js/difftool-builtin'Junio C Hamano2017-04-162-18/+39
|\ | | | | | | | | | | | | | | Code cleanup. * js/difftool-builtin: difftool: fix use-after-free difftool: avoid strcpy
| * difftool: fix use-after-freejs/difftool-builtinJohannes Schindelin2017-04-132-2/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The left and right base directories were pointed to the buf field of two strbufs, which were subject to change. A contrived test case shows the problem where a file with a long enough name to force the strbuf to grow is up-to-date (hence the code path is used where the work tree's version of the file is reused), and then a file that is not up-to-date needs to be written (hence the code path is used where checkout_entry() uses the previously recorded base_dir that is invalid by now). Let's just copy the base_dir strings for use with checkout_entry(), never touch them until the end, and release them then. This is an easily verifiable fix (as opposed to the next-obvious alternative: to re-set base_dir after every loop iteration). This fixes https://github.com/git-for-windows/git/issues/1124 Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
| * difftool: avoid strcpyJeff King2017-03-301-16/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to checkout files, difftool reads "diff --raw" output and feeds the names to checkout_entry(). That function requires us to have a "struct cache_entry". And because that struct uses a FLEX_ARRAY for the name field, we have to actually copy in our new name. The current code allocates a single re-usable cache_entry that can hold a name up to PATH_MAX, and then copies filenames into it using strcpy(). But there's no guarantee that incoming names are smaller than PATH_MAX. They've come from "diff --raw" output which might be diffing between two trees (and hence we'd be subject to the PATH_MAX of some other system, or even none at all if they were created directly via "update-index"). We can fix this by using make_cache_entry() to create a correctly-sized cache_entry for each name. This incurs an extra allocation per file, but this is negligible compared to actually writing out the file contents. To make this simpler, we can push this procedure into a new helper function. Note that we can also get rid of the "len" variables for src_path and dst_path (and in fact we must, as the compiler complains that they are unused). Signed-off-by: Jeff King <peff@peff.net> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | Merge branch 'sb/unpack-trees-would-lose-submodule-message-update'Junio C Hamano2017-04-161-1/+1
|\ \ | | | | | | | | | | | | | | | | | | Update an error message. * sb/unpack-trees-would-lose-submodule-message-update: unpack-trees.c: align submodule error message to the other error messages
| * | unpack-trees.c: align submodule error message to the other error messagessb/unpack-trees-would-lose-submodule-message-updateStefan Beller2017-03-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | As the place holder in the error message is for multiple submodules, we don't want to encapsulate the string place holder in single quotes. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | Merge branch 'ab/regen-perl-mak-with-different-perl'Junio C Hamano2017-04-161-0/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update the build dependency so that an update to /usr/bin/perl etc. result in recomputation of perl.mak file. * ab/regen-perl-mak-with-different-perl: perl: regenerate perl.mak if perl -V changes
| * | | perl: regenerate perl.mak if perl -V changesab/regen-perl-mak-with-different-perlÆvar Arnfjörð Bjarmason2017-03-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change the perl/perl.mak build process so that the file is regenerated if the output of "perl -V" changes. Before this change updating e.g. /usr/bin/perl to a new major version would cause the next "make" command to fail, since perl.mak has hardcoded paths to perl library paths retrieved from its first run. Now the logic added in commit ee9be06770 ("perl: detect new files in MakeMaker builds", 2012-07-27) is extended to regenerate perl/perl.mak if there's any change to "perl -V". This will in some cases redundantly trigger perl/perl.mak to be re-made, e.g. if @INC is modified in ways the build process doesn't care about through sitecustomize.pl, but the common case is that we just do the right thing and re-generate perl/perl.mak when needed. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | Merge branch 'sb/show-diff-for-submodule-in-diff-fix'Junio C Hamano2017-04-162-0/+30
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "git diff --submodule=diff" learned to work better in a project with a submodule that in turn has its own submodules. * sb/show-diff-for-submodule-in-diff-fix: diff: submodule inline diff to initialize env array.
| * | | | diff: submodule inline diff to initialize env array.sb/show-diff-for-submodule-in-diff-fixStefan Beller2017-04-022-0/+30
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | David reported: > When I try to run `git diff --submodule=diff` in a submodule which has > it's own submodules that have changes I get the error: fatal: bad > object. This happens, because we do not properly initialize the environment in which the diff is run in the submodule. That means we inherit the environment from the main process, which sets environment variables. (Apparently we do set environment variables which we do not set when not in a submodules, i.e. the .git directory is linked) This commit, just like fd47ae6a5b (diff: teach diff to display submodule difference with an inline diff, 2016-08-31) introduces bad test code (i.e. hard coded hash values), which will be cleanup up in a later patch. Reported-by: David Parrish <daveparrish@gmail.com> Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | Merge branch 'qp/bisect-docfix'Junio C Hamano2017-04-161-1/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Doc update. * qp/bisect-docfix: git-bisect.txt: add missing word
| * | | | git-bisect.txt: add missing wordqp/bisect-docfixQuentin Pradet2017-04-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Quentin Pradet <quentin.pradet@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | | Merge branch 'mm/ls-files-s-doc'Junio C Hamano2017-04-161-1/+1
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Doc update. * mm/ls-files-s-doc: Documentation: document elements in "ls-files -s" output in order
| * | | | | Documentation: document elements in "ls-files -s" output in ordermm/ls-files-s-docMostyn Bramley-Moore2017-04-011-1/+1
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | List the fields in order of appearance in the command output. Signed-off-by: Mostyn Bramley-Moore <mostyn@antipode.se> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | | Merge branch 'jk/loose-object-info-report-error'Junio C Hamano2017-04-163-1/+27
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update error handling for codepath that deals with corrupt loose objects. * jk/loose-object-info-report-error: index-pack: detect local corruption in collision check sha1_loose_object_info: return error for corrupted objects
| * | | | | index-pack: detect local corruption in collision checkjk/loose-object-info-report-errorJeff King2017-04-012-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we notice that we have a local copy of an incoming object, we compare the two objects to make sure we haven't found a collision. Before we get to the actual object bytes, though, we compare the type and size from sha1_object_info(). If our local object is corrupted, then the type will be OBJ_BAD, which obviously will not match the incoming type, and we'll report "SHA1 COLLISION FOUND" (with capital letters and everything). This is confusing, as the problem is not a collision but rather local corruption. We should report that instead (just like we do if reading the rest of the object content fails a few lines later). Note that we _could_ just ignore the error and mark it as a non-collision. That would let you "git fetch" to replace a corrupted object. But it's not a very reliable method for repairing a repository. The earlier want/have negotiation tries to get the other side to omit objects we already have, and it would not realize that we are "missing" this corrupted object. So we're better off complaining loudly when we see corruption, and letting the user take more drastic measures to repair (like making a full clone elsewhere and copying the pack into place). Note that the test sets transfer.unpackLimit in the receiving repository so that we use index-pack (which is what does the collision check). Normally for such a small push we'd use unpack-objects, which would simply try to write the loose object, and discard the new one when we see that there's already an old one. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
| * | | | | sha1_loose_object_info: return error for corrupted objectsJeff King2017-04-012-1/+8
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When sha1_loose_object_info() finds that a loose object file cannot be stat(2)ed or mmap(2)ed, it returns -1 to signal an error to the caller. However, if it found that the loose object file is corrupt and the object data cannot be used from it, it stuffs OBJ_BAD into "type" field of the object_info, but returns zero (i.e., success), which can confuse callers. This is due to 052fe5eac (sha1_loose_object_info: make type lookup optional, 2013-07-12), which switched the return to a strict success/error, rather than returning the type (but botched the return). Callers of regular sha1_object_info() don't notice the difference, as that function returns the type (which is OBJ_BAD in this case). However, direct callers of sha1_object_info_extended() see the function return success, but without setting any meaningful values in the object_info struct, leading them to access potentially uninitialized memory. The easiest way to see the bug is via "cat-file -s", which will happily ignore the corruption and report whatever value happened to be in the "size" variable. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | | Merge branch 'jc/bs-t-is-not-a-tab-for-sed'Junio C Hamano2017-04-161-2/+2
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Code cleanup. * jc/bs-t-is-not-a-tab-for-sed: contrib/git-resurrect.sh: do not write \t for HT in sed scripts
| * | | | | contrib/git-resurrect.sh: do not write \t for HT in sed scriptsjc/bs-t-is-not-a-tab-for-sedJunio C Hamano2017-03-311-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Just like we did in 0d1d6e50 ("t/t7003: replace \t with literal tab in sed expression", 2010-08-12), avoid writing "\t" for HT in sed scripts, which is not portable. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | | | Merge branch 'jc/unused-symbols'Junio C Hamano2017-04-162-2/+1
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Code cleanup. * jc/unused-symbols: remote.[ch]: parse_push_cas_option() can be static
| * | | | | | remote.[ch]: parse_push_cas_option() can be staticjc/unused-symbolsJunio C Hamano2017-03-312-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since 068c77a5 ("builtin/send-pack.c: use parse_options API", 2015-08-19), there is no external user of this helper function. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | | | | | | Merge branch 'jk/snprintf-cleanups'Junio C Hamano2017-04-1628-224/+239
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Code clean-up. * jk/snprintf-cleanups: daemon: use an argv_array to exec children gc: replace local buffer with git_path transport-helper: replace checked snprintf with xsnprintf convert unchecked snprintf into xsnprintf combine-diff: replace malloc/snprintf with xstrfmt replace unchecked snprintf calls with heap buffers receive-pack: print --pack-header directly into argv array name-rev: replace static buffer with strbuf create_branch: use xstrfmt for reflog message create_branch: move msg setup closer to point of use avoid using mksnpath for refs avoid using fixed PATH_MAX buffers for refs fetch: use heap buffer to format reflog tag: use strbuf to format tag header diff: avoid fixed-size buffer for patch-ids odb_mkstemp: use git_path_buf odb_mkstemp: write filename into strbuf do not check odb_mkstemp return value for errors
| * | | | | | | daemon: use an argv_array to exec childrenJeff King2017-03-301-21/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Our struct child_process already has its own argv_array. Let's use that to avoid having to format options into separate buffers. Note that we'll need to declare the child process outside of the run_service_command() helper to do this. But that opens up a further simplification, which is that the helper can append to our argument list, saving each caller from specifying "." manually. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | gc: replace local buffer with git_pathJeff King2017-03-301-7/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We probe the "17/" loose object directory for auto-gc, and use a local buffer to format the path. We can just use git_path() for this. It handles paths of any length (reducing our error handling). And because we feed the result straight to a system call, we can just use the static variant. Note that git_path also knows the string "objects/" is special, and will replace it with git_object_directory() when necessary. Another alternative would be to use sha1_file_name() for the pretend object "170000...", but that ends up being more hassle for no gain, as we have to truncate the final path component. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | transport-helper: replace checked snprintf with xsnprintfJeff King2017-03-301-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can use xsnprintf to do our truncation check with less code. The error message isn't as specific, but the point is that this isn't supposed to trigger in the first place (because our buffer is big enough to handle any int). Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | convert unchecked snprintf into xsnprintfJeff King2017-03-305-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These calls to snprintf should always succeed, because their input is small and fixed. Let's use xsnprintf to make sure this is the case (and to make auditing for actual truncation easier). These could be candidates for turning into heap buffers, but they fall into a few broad categories that make it not worth doing: - formatting single numbers is simple enough that we can see the result should fit - the size of a sha1 is likewise well-known, and I didn't want to cause unnecessary conflicts with the ongoing process to convert these constants to GIT_MAX_HEXSZ - the interface for curl_errorstr is dictated by curl Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | combine-diff: replace malloc/snprintf with xstrfmtJeff King2017-03-301-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no need to use the magic "100" when a strbuf can do it for us. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | replace unchecked snprintf calls with heap buffersJeff King2017-03-304-14/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We'd prefer to avoid unchecked snprintf calls because truncation can lead to unexpected results. These are all cases where truncation shouldn't ever happen, because the input to snprintf is fixed in size. That makes them candidates for xsnprintf(), but it's simpler still to just use the heap, and then nobody has to wonder if "100" is big enough. We'll use xstrfmt() where possible, and a strbuf when we need the resulting size or to reuse the same buffer in a loop. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | receive-pack: print --pack-header directly into argv arrayJeff King2017-03-301-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After receive-pack reads the pack header from the client, it feeds the already-read part to index-pack and unpack-objects via their --pack-header command-line options. To do so, we format it into a fixed buffer, then duplicate it into the child's argv_array. Our buffer is long enough to handle any possible input, so this isn't wrong. But it's more complicated than it needs to be; we can just argv_array_pushf() the final value and avoid the intermediate copy. This drops the magic number and is more efficient, too. Note that we need to push to the argv_array in order, which means we can't do the push until we are in the "unpack-objects versus index-pack" conditional. Rather than duplicate the slightly complicated format specifier, I pushed it into a helper function. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | name-rev: replace static buffer with strbufJeff King2017-03-301-9/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When name-rev needs to format an actual name, we do so into a fixed-size buffer. That includes the actual ref tip, as well as any traversal information. Since refs can exceed 1024 bytes, this means you can get a bogus result. E.g., doing: git tag $(perl -e 'print join("/", 1..1024)') git describe --contains HEAD^ results in ".../282/283", when it should be ".../1023/1024~1". We can solve this by using a heap buffer. We'll use a strbuf, which lets us write into the same buffer from our loop without having to reallocate. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | create_branch: use xstrfmt for reflog messageJeff King2017-03-301-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We generate a reflog message that contains some fixed text plus a branch name, and use a buffer of size PATH_MAX + 20. This mostly works if you assume that refnames are shorter than PATH_MAX, but: 1. That's not necessarily true. PATH_MAX is not always the filesystem's limit. 2. The "20" is not sufficiently large for the fixed text anyway. Let's just switch to a heap buffer so we don't have to even care. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | create_branch: move msg setup closer to point of useJeff King2017-03-301-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In create_branch() we write the reflog msg into a buffer in the main function, but then use it only inside a conditional. If you carefully follow the logic, you can confirm that we never use the buffer uninitialized nor write when it would not be used. But we can make this a lot more obvious by simply moving the write step inside the conditional. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | avoid using mksnpath for refsJeff King2017-03-301-18/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Like the previous commit, we'd like to avoid the assumption that refs fit into PATH_MAX-sized buffers. These callsites have an extra twist, though: they write the refnames using mksnpath. This does two things beyond a regular snprintf: 1. It quietly writes "/bad-path/" when truncation occurs. This saves the caller having to check the error code, but if you aren't actually feeding the result to a system call (and we aren't here), it's questionable. 2. It calls cleanup_path(), which removes leading instances of "./". That's questionable when dealing with refnames, as we could silently canonicalize a syntactically bogus refname into a valid one. Let's convert each case to use a strbuf. This is preferable to xstrfmt() because we can reuse the same buffer as we loop. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | avoid using fixed PATH_MAX buffers for refsJeff King2017-03-304-39/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many functions which handle refs use a PATH_MAX-sized buffer to do so. This is mostly reasonable as we have to write loose refs into the filesystem, and at least on Linux the 4K PATH_MAX is big enough that nobody would care. But: 1. The static PATH_MAX is not always the filesystem limit. 2. On other platforms, PATH_MAX may be much smaller. 3. As we move to alternate ref storage, we won't be bound by filesystem limits. Let's convert these to heap buffers so we don't have to worry about truncation or size limits. We may want to eventually constrain ref lengths for sanity and to prevent malicious names, but we should do so consistently across all platforms, and in a central place (like the ref code). Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | fetch: use heap buffer to format reflogJeff King2017-03-301-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Part of the reflog content comes from the environment, which can be much larger than our fixed buffer. Let's use a heap buffer so we avoid truncating it. Signed-off-by: Jeff King <peff@peff.net>
| * | | | | | | tag: use strbuf to format tag headerJeff King2017-03-301-15/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We format the tag header into a fixed 1024-byte buffer. But since the tag-name and tagger ident can be arbitrarily large, we may unceremoniously die with "tag header too big". Let's just use a strbuf instead. Note that it looks at first glance like we can just format this directly into the "buf" strbuf where it will ultimately go. But that buffer may already contain the tag message, and we have no easy way to prepend formatted data to a strbuf (we can only splice in an already-generated buffer). This isn't a performance-critical path, so going through an extra buffer isn't a big deal. Signed-off-by: Jeff King <peff@peff.net>