Re: [PATCH 2/2] Avoid potentially dereferencing a NULL pointer

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+To: Austin Clements <amdragon@MIT.EDU>, \r
+From: Justus Winter <4winter@informatik.uni-hamburg.de>\r
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+References:\r
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+Subject: Re: [PATCH 2/2] Avoid potentially dereferencing a NULL pointer\r
+Date: Mon, 24 Sep 2012 14:55:10 +0200\r
+Cc: notmuch@notmuchmail.org\r
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+\r
+Quoting Austin Clements (2012-09-22 18:19:08)\r
+> Quoth Justus Winter on Sep 21 at  2:50 pm:\r
+> > GMIME_IS_MULTIPART and GMIME_IS_MESSAGE both handle NULL pointers\r
+> > gracefully, but the G_OBJECT_TYPE used in the error handling block\r
+> > dereferences it without checking it first.\r
+> > =\r
+\r
+> > Fix this by checking whether parent->part is valid.\r
+> > =\r
+\r
+> > Found using the clang static analyzer.\r
+> =\r
+\r
+> Neat.\r
+\r
+Yes. Besides this the code turns up no warnings (modulo one false\r
+positive, clang doesn't understand that progress_notify is never\r
+called if it's NULL in notmuch_database_upgrade b/c the signal handler\r
+isn't set up then).\r
+\r
+> Can this actually happen, though?  If so, I think this point is too\r
+> late to be checking for a NULL part field.  It should probably be\r
+> checked when the mime_node_t is created so that mime_node_t never has\r
+> a NULL part field.\r
+\r
+I'm not sure actually. Then again this patch isn't hacky at all and\r
+being somewhat defensive isn't bad imho.\r
+\r
+Justus\r