Merge branch 'jk/push-client-deadlock-fix'

"git push" from a corrupt repository that attempts to push a large
number of refs deadlocked; the thread to relay rejection notices
for these ref updates blocked on writing them to the main thread,
after the main thread at the receiving end notices that the push
failed and decides not to read these notices and return a failure.

* jk/push-client-deadlock-fix:
t5504: drop sigpipe=ok from push tests
fetch-pack: isolate sigpipe in demuxer thread
send-pack: isolate sigpipe in demuxer thread
run-command: teach async threads to ignore SIGPIPE
send-pack: close demux pipe before finishing async process

diff --git a/fetch-pack.c b/fetch-pack.c
index f96f6dfb35afb419ac38fcec9b4013fbf0e6d36d..b501d5c320a5117020a934a50fce2a356b0c2f0e 100644 (file)
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -15,7 +15,6 @@
 #include "version.h"
 #include "prio-queue.h"
 #include "sha1-array.h"
-#include "sigchain.h"
 
 static int transfer_unpack_limit = -1;
 static int fetch_unpack_limit = -1;
@@ -674,10 +673,8 @@ static int sideband_demux(int in, int out, void *data)
        int *xd = data;
        int ret;
 
-       sigchain_push(SIGPIPE, SIG_IGN);
        ret = recv_sideband("fetch-pack", xd[0], out);
        close(out);
-       sigchain_pop(SIGPIPE);
        return ret;
 }
 
@@ -701,6 +698,7 @@ static int get_pack(struct fetch_pack_args *args,
                demux.proc = sideband_demux;
                demux.data = xd;
                demux.out = -1;
+               demux.isolate_sigpipe = 1;
                if (start_async(&demux))
                        die("fetch-pack: unable to fork off sideband"
                            " demultiplexer");

diff --git a/run-command.c b/run-command.c
index 8c7115ade496e5bbaf1b584199da8f3ab21fa087..e4593cd99b13fdbfec02939526ac151270aa20f5 100644 (file)
--- a/run-command.c
+++ b/run-command.c
@@ -590,6 +590,16 @@ static void *run_thread(void *data)
        struct async *async = data;
        intptr_t ret;
 
+       if (async->isolate_sigpipe) {
+               sigset_t mask;
+               sigemptyset(&mask);
+               sigaddset(&mask, SIGPIPE);
+               if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) {
+                       ret = error("unable to block SIGPIPE in async thread");
+                       return (void *)ret;
+               }
+       }
+
        pthread_setspecific(async_key, async);
        ret = async->proc(async->proc_in, async->proc_out, async->data);
        return (void *)ret;

diff --git a/run-command.h b/run-command.h
index de1727efab9d7e57a41626ac8bd89e5149412dc8..11f76b04edf65fe6117604782c220e55b2d80661 100644 (file)
--- a/run-command.h
+++ b/run-command.h
@@ -116,6 +116,7 @@ struct async {
        int proc_in;
        int proc_out;
 #endif
+       int isolate_sigpipe;
 };
 
 int start_async(struct async *async);

diff --git a/send-pack.c b/send-pack.c
index 047bd18fde3d09921902ebb656ab78bfbcf940a8..37ee04ea3bf41b3bc4b0b920d52449c2f6d681d7 100644 (file)
--- a/send-pack.c
+++ b/send-pack.c
@@ -518,6 +518,7 @@ int send_pack(struct send_pack_args *args,
                demux.proc = sideband_demux;
                demux.data = fd;
                demux.out = -1;
+               demux.isolate_sigpipe = 1;
                if (start_async(&demux))
                        die("send-pack: unable to fork off sideband demultiplexer");
                in = demux.out;
@@ -531,8 +532,10 @@ int send_pack(struct send_pack_args *args,
                                close(out);
                        if (git_connection_is_socket(conn))
                                shutdown(fd[0], SHUT_WR);
-                       if (use_sideband)
+                       if (use_sideband) {
+                               close(demux.out);
                                finish_async(&demux);
+                       }
                        fd[1] = -1;
                        return -1;
                }
@@ -551,11 +554,11 @@ int send_pack(struct send_pack_args *args,
                packet_flush(out);
 
        if (use_sideband && cmds_sent) {
+               close(demux.out);
                if (finish_async(&demux)) {
                        error("error in sideband demultiplexer");
                        ret = -1;
                }
-               close(demux.out);
        }
 
        if (ret < 0)

diff --git a/t/t5504-fetch-receive-strict.sh b/t/t5504-fetch-receive-strict.sh
index a3e12d295afedb170b3a917ce9d23122c1a0bc1d..44f3d5fb284e9848180df9ed9cfbc44a91762277 100755 (executable)
--- a/t/t5504-fetch-receive-strict.sh
+++ b/t/t5504-fetch-receive-strict.sh
@@ -100,11 +100,8 @@ test_expect_success 'push with receive.fsckobjects' '
                git config receive.fsckobjects true &&
                git config transfer.fsckobjects false
        ) &&
-       test_must_fail ok=sigpipe git push --porcelain dst master:refs/heads/test >act &&
-       {
-               test_cmp exp act ||
-               ! test -s act
-       }
+       test_must_fail git push --porcelain dst master:refs/heads/test >act &&
+       test_cmp exp act
 '
 
 test_expect_success 'push with transfer.fsckobjects' '
@@ -114,7 +111,8 @@ test_expect_success 'push with transfer.fsckobjects' '
                cd dst &&
                git config transfer.fsckobjects true
        ) &&
-       test_must_fail ok=sigpipe git push --porcelain dst master:refs/heads/test >act
+       test_must_fail git push --porcelain dst master:refs/heads/test >act &&
+       test_cmp exp act
 '
 
 cat >bogus-commit <<\EOF