From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-x42d.google.com (mail-pf1-x42d.google.com [IPv6:2607:f8b0:4864:20::42d]) by sourceware.org (Postfix) with ESMTPS id 71F693858406 for ; Wed, 10 Aug 2022 17:21:55 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 71F693858406 Received: by mail-pf1-x42d.google.com with SMTP id y141so14288497pfb.7 for ; Wed, 10 Aug 2022 10:21:55 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=t8VDmmANPsqiMKRFYKZdZcmFB5DiH3DAtx60w2V3e2k=; b=tMUhIiqFMr0lmwl4QYwK0r/J55sLvJsCbAwe18zm8UcychLVJV2fke+u3VGyuYRs0z 2jb3r4Hu3fXCtvvcwms8CqlWrwd1AEFaizzqH396P2N0dLnOCy6QiqM8z3Uh52lMaO1G egF+KnY+WBRIpFz720YJPwOj5DiUUtqx+TuremlHSQ1+Q3uw9sVNn3nM1URDk6rKD0MI JykwM4GlluQpA3qVeFtFVLw8jnyff+GB3CTe97bWmoH/i9WPn/I/rFKWFIPMrBo4FXGR Xvnm+qhQRmOG3ExwdDZiVTkYkoDNQgqKSfp37CEfOodrIjI/QyyYRIDkwvl+Uth2EUzd n5Sw== X-Gm-Message-State: ACgBeo2Ts+leUiJ4fHyAUx6uBSbkMQ2+4Y8emU8vZutS+ARbNDCRZBG7 6tS0MhEK9u1S22xNwwLi69xFhV/fMipnYzn56RU= X-Google-Smtp-Source: AA6agR6aJ02UNzdPgJgakGyg581aF6aC3tZXVBWSkXPueHMgp72WtJMAEecy1/Q/nEMJ75gccLldIcT2YkKND0EuxP8= X-Received: by 2002:a63:8bc3:0:b0:41d:4b74:b975 with SMTP id j186-20020a638bc3000000b0041d4b74b975mr14903517pge.309.1660152114245; Wed, 10 Aug 2022 10:21:54 -0700 (PDT) MIME-Version: 1.0 References: <2022febb8297564e4cd6f349f16bba6e8b91509b.camel@redhat.com> In-Reply-To: <2022febb8297564e4cd6f349f16bba6e8b91509b.camel@redhat.com> From: Mir Immad Date: Wed, 10 Aug 2022 22:51:41 +0530 Message-ID: Subject: Re: [PATCH] analyzer: fix ICE casued by dup2 in sm-fd.cc[PR106551] To: David Malcolm Cc: gcc-patches@gcc.gnu.org X-Spam-Status: No, score=-8.0 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_ENVFROM_END_DIGIT, FREEMAIL_FROM, GIT_PATCH_0, HTML_MESSAGE, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 10 Aug 2022 17:21:57 -0000 > Can you please rebase and see if your patch > does fix it? No, the patch that I sent did not attempt to fix this. Now that I have made the correction, XFAIL in fd-uninit-1.c has changed to XPASS. Should i remove the dg-bogus warning from fd-uninit-1.c test_1? Thanks. Immad. On Wed, Aug 10, 2022 at 10:26 PM David Malcolm wrote: > On Wed, 2022-08-10 at 20:34 +0530, Mir Immad wrote: > > > if you convert the "int m;" locals into an extern global, like in > > > comment #0 of bug 106551, does that still trigger the crash on the > > > unpatched sm-fd.cc? > > > > Yes, it does, since m would be in "m_start" state. I'm sending an > > updated > > patch. > > Great! > > Note that I recently committed a fix for bug 106573, which has an xfail > on a dg-bogus to mark a false positive which your patch hopefully also > fixes (in fd-uninit-1.c). Can you please rebase and see if your patch > does fix it? > > Thanks > Dave > > > > > > Thanks > > Immad. > > > > On Wed, Aug 10, 2022 at 1:32 AM David Malcolm > > wrote: > > > > > On Tue, 2022-08-09 at 21:42 +0530, Immad Mir wrote: > > > > This patch fixes the ICE caused by valid_to_unchecked_state, > > > > at analyzer/sm-fd.cc by handling the m_start state in > > > > check_for_dup. > > > > > > > > Tested lightly on x86_64. > > > > > > > > gcc/analyzer/ChangeLog: > > > > PR analyzer/106551 > > > > * sm-fd.cc (check_for_dup): handle the m_start > > > > state when transitioning the state of LHS > > > > of dup, dup2 and dup3 call. > > > > > > > > gcc/testsuite/ChangeLog: > > > > * gcc.dg/analyzer/fd-dup-1.c: New testcases. > > > > > > > > Signed-off-by: Immad Mir > > > > --- > > > > gcc/analyzer/sm-fd.cc | 4 ++-- > > > > gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c | 28 > > > > +++++++++++++++++++++++- > > > > 2 files changed, 29 insertions(+), 3 deletions(-) > > > > > > > > diff --git a/gcc/analyzer/sm-fd.cc b/gcc/analyzer/sm-fd.cc > > > > index 8bb76d72b05..c8b9930a7b6 100644 > > > > --- a/gcc/analyzer/sm-fd.cc > > > > +++ b/gcc/analyzer/sm-fd.cc > > > > @@ -983,7 +983,7 @@ fd_state_machine::check_for_dup (sm_context > > > > *sm_ctxt, const supernode *node, > > > > case DUP_1: > > > > if (lhs) > > > > { > > > > - if (is_constant_fd_p (state_arg_1)) > > > > + if (is_constant_fd_p (state_arg_1) || state_arg_1 == > > > > m_start) > > > > sm_ctxt->set_next_state (stmt, lhs, > > > > m_unchecked_read_write); > > > > else > > > > sm_ctxt->set_next_state (stmt, lhs, > > > > @@ -1011,7 +1011,7 @@ fd_state_machine::check_for_dup (sm_context > > > > *sm_ctxt, const supernode *node, > > > > file descriptor i.e the first argument. */ > > > > if (lhs) > > > > { > > > > - if (is_constant_fd_p (state_arg_1)) > > > > + if (is_constant_fd_p (state_arg_1) || state_arg_1 == > > > > m_start) > > > > sm_ctxt->set_next_state (stmt, lhs, > > > > m_unchecked_read_write); > > > > else > > > > sm_ctxt->set_next_state (stmt, lhs, > > > > diff --git a/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c > > > > b/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c > > > > index eba2570568f..ed4d6de57db 100644 > > > > --- a/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c > > > > +++ b/gcc/testsuite/gcc.dg/analyzer/fd-dup-1.c > > > > @@ -220,4 +220,30 @@ test_19 (const char *path, void *buf) > > > > close (fd); > > > > } > > > > > > > > -} > > > > \ No newline at end of file > > > > +} > > > > + > > > > +void > > > > +test_20 () > > > > +{ > > > > + int m; > > > > + int fd = dup (m); /* { dg-warning "'dup' on possibly invalid > > > > file descriptor 'm'" } */ > > > > + close (fd); > > > > +} > > > > + > > > > +void > > > > +test_21 () > > > > +{ > > > > + int m; > > > > + int fd = dup2 (m, 1); /* { dg-warning "'dup2' on possibly > > > > invalid file descriptor 'm'" } */ > > > > + close (fd); > > > > +} > > > > + > > > > +void > > > > +test_22 (int flags) > > > > +{ > > > > + int m; > > > > + int fd = dup3 (m, 1, flags); /* { dg-warning "'dup3' on > > > > possibly > > > > invalid file descriptor 'm'" } */ > > > > + close (fd); > > > > +} > > > > > > Thanks for the updated patch. > > > > > > The test cases looked suspicious to me - I was wondering why the > > > analyzer doesn't complain about the uninitialized values being > > > passed > > > to the various dup functions as parameters. So your test cases > > > seem to > > > have uncovered a hidden pre-existing bug in the analyzer's > > > uninitialized value detection, which I've filed for myself to deal > > > with > > > as PR analyzer/106573. > > > > > > If you convert the "int m;" locals into an extern global, like in > > > comment #0 of bug 106551, does that still trigger the crash on the > > > unpatched sm-fd.cc? If so, then that's greatly preferable as a > > > regression test, since otherwise I'll have to modify that test case > > > when I fix bug 106573. > > > > > > Dave > > > > > > > > > > > > > > >