{"id":351,"date":"2016-02-16T16:46:17","date_gmt":"2016-02-16T14:46:17","guid":{"rendered":"http:\/\/blogs.gentoo.org\/ago\/?p=351"},"modified":"2016-09-07T14:37:29","modified_gmt":"2016-09-07T12:37:29","slug":"portage-utils-heap-based-buffer-overflow-in-qlop-c","status":"publish","type":"post","link":"https:\/\/blogs.gentoo.org\/ago\/2016\/02\/16\/portage-utils-heap-based-buffer-overflow-in-qlop-c\/","title":{"rendered":"portage-utils: heap-based buffer overflow in qlop.c"},"content":{"rendered":"<p><strong>Description<\/strong>:<br \/>\n<a href=\"https:\/\/wiki.gentoo.org\/wiki\/Portage-utils\">Portage-utils<\/a> is small and fast portage helper tools written in C.<\/p>\n<p>I discovered that a crafted file is able to cause an heap-based buffer overflow.<\/p>\n<p>The complete ASan output:<\/p>\n<pre><font size=\"2\">~ # qlop -f $CRAFTED_FILE -s\r\nMon Jan 25 11:38:31 2016 &gt;&gt;&gt; gentoo\r\n=================================================================\r\n==14281==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61900001e44a at pc 0x000000425676 bp 0x7fff2b3f3970 sp 0x7fff2b3f3130\r\nREAD of size 1 at 0x61900001e44a thread T0\r\n    #0 0x425675 in __interceptor_strncmp \/var\/tmp\/portage\/sys-devel\/llvm-3.7.1\/work\/llvm-3.7.1.src\/projects\/compiler-rt\/lib\/asan\/..\/sanitizer_common\/sanitizer_common_interceptors.inc:218:3\r\n    #1 0x50d5b1 in show_sync_history \/tmp\/portage\/app-portage\/portage-utils-0.60\/work\/portage-utils-0.60\/.\/qlop.c:350:7\r\n    #2 0x50d5b1 in qlop_main \/tmp\/portage\/app-portage\/portage-utils-0.60\/work\/portage-utils-0.60\/.\/qlop.c:687\r\n    #3 0x4e7f22 in q_main \/tmp\/portage\/app-portage\/portage-utils-0.60\/work\/portage-utils-0.60\/.\/q.c:79:10\r\n    #4 0x4e7afe in main \/tmp\/portage\/app-portage\/portage-utils-0.60\/work\/portage-utils-0.60\/main.c:1405:9\r\n    #5 0x7fafd8594854 in __libc_start_main \/tmp\/portage\/sys-libs\/glibc-2.21-r1\/work\/glibc-2.21\/csu\/libc-start.c:289\r\n    #6 0x4192f8 in _init (\/usr\/bin\/q+0x4192f8)\r\n\r\n0x61900001e44a is located 0 bytes to the right of 970-byte region [0x61900001e080,0x61900001e44a)\r\nallocated by thread T0 here:\r\n    #0 0x4a839e in realloc \/var\/tmp\/portage\/sys-devel\/llvm-3.7.1\/work\/llvm-3.7.1.src\/projects\/compiler-rt\/lib\/asan\/asan_malloc_linux.cc:61:3\r\n    #1 0x7fafd85dc95f in getdelim \/tmp\/portage\/sys-libs\/glibc-2.21-r1\/work\/glibc-2.21\/libio\/iogetdelim.c:106\r\n\r\nSUMMARY: AddressSanitizer: heap-buffer-overflow \/var\/tmp\/portage\/sys-devel\/llvm-3.7.1\/work\/llvm-3.7.1.src\/projects\/compiler-rt\/lib\/asan\/..\/sanitizer_common\/sanitizer_common_interceptors.inc:218:3 in __interceptor_strncmp\r\nShadow bytes around the buggy address:\r\n  0x0c327fffbc30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n  0x0c327fffbc40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n  0x0c327fffbc50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n  0x0c327fffbc60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n  0x0c327fffbc70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\r\n=&gt;0x0c327fffbc80: 00 00 00 00 00 00 00 00 00[02]fa fa fa fa fa fa\r\n  0x0c327fffbc90: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\n  0x0c327fffbca0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa\r\n  0x0c327fffbcb0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd\r\n  0x0c327fffbcc0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd\r\n  0x0c327fffbcd0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd                                                                                                                                                                                                              \r\nShadow byte legend (one shadow byte represents 8 application bytes):                                                                                                                                                                                                           \r\n  Addressable:           00                                                                                                                                                                                                                                                    \r\n  Partially addressable: 01 02 03 04 05 06 07                                                                                                                                                                                                                                  \r\n  Heap left redzone:       fa                                                                                                                                                                                                                                                  \r\n  Heap right redzone:      fb                                                                                                                                                                                                                                                  \r\n  Freed heap region:       fd                                                                                                                                                                                                                                                  \r\n  Stack left redzone:      f1                                                                                                                                                                                                                                                  \r\n  Stack mid redzone:       f2                                                                                                                                                                                                                                                  \r\n  Stack right redzone:     f3                                                                                                                                                                                                                                                  \r\n  Stack partial redzone:   f4                                                                                                                                                                                                                                                  \r\n  Stack after return:      f5                                                                                                                                                                                                                                                  \r\n  Stack use after scope:   f8                                                                                                                                                                                                                                                  \r\n  Global redzone:          f9                                                                                                                                                                                                                                                  \r\n  Global init order:       f6                                                                                                                                                                                                                                                  \r\n  Poisoned by user:        f7                                                                                                                                                                                                                                                  \r\n  Container overflow:      fc                                                                                                                                                                                                                                                  \r\n  Array cookie:            ac                                                                                                                                                                                                                                                  \r\n  Intra object redzone:    bb                                                                                                                                                                                                                                                  \r\n  ASan internal:           fe                                                                                                                                                                                                                                                  \r\n  Left alloca redzone:     ca                                                                                                                                                                                                                                                  \r\n  Right alloca redzone:    cb                                                                                                                                                                                                                                                  \r\n==14281==ABORTING\r\n<\/font><\/pre>\n<p><strong>Affected version:<\/strong><br \/>\nAll versions.<\/p>\n<p><strong>Fixed version:<\/strong><br \/>\n0.61<\/p>\n<p><strong>Commit fix:<\/strong><br \/>\n<a href=\"https:\/\/gitweb.gentoo.org\/proj\/portage-utils.git\/commit\/?id=7aff0263204d80304108dbe4f0061f44ed8f189f\">https:\/\/gitweb.gentoo.org\/proj\/portage-utils.git\/commit\/?id=7aff0263204d80304108dbe4f0061f44ed8f189f<\/a><\/p>\n<p><strong>Credit:<\/strong><br \/>\nThis bug was discovered by Agostino Sarubbo of Gentoo.<\/p>\n<p><strong>Timeline:<\/strong><br \/>\n2016-01-26: bug discovered<br \/>\n2016-01-27: bug reported to upstream<br \/>\n2016-01-29: upstream release a fix<br \/>\n2016-02-16: blog post about the issue<\/p>\n<p><strong>Note:<\/strong><br \/>\nThis bug was found with <a href=\"http:\/\/lcamtuf.coredump.cx\/afl\">American Fuzzy Lop<\/a>.<\/p>\n<p><strong>Permalink:<\/strong><\/p>\n<blockquote data-secret=\"21R3NLeSWQ\" class=\"wp-embedded-content\"><p><a href=\"http:\/\/blogs.gentoo.org\/ago\/2016\/02\/16\/portage-utils-heap-based-buffer-overflow-in-qlop-c\/\">portage-utils: heap-based buffer overflow in qlop.c<\/a><\/p><\/blockquote>\n<p><iframe class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; clip: rect(1px, 1px, 1px, 1px);\" src=\"http:\/\/blogs.gentoo.org\/ago\/2016\/02\/16\/portage-utils-heap-based-buffer-overflow-in-qlop-c\/embed\/#?secret=21R3NLeSWQ\" data-secret=\"21R3NLeSWQ\" width=\"600\" height=\"338\" title=\"&#8220;portage-utils: heap-based buffer overflow in qlop.c&#8221; &#8212; agostino&#039;s blog\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Description: Portage-utils is small and fast portage helper tools written in C. I discovered that a crafted file is able to cause an heap-based buffer overflow. The complete ASan output: ~ # qlop -f $CRAFTED_FILE -s Mon Jan 25 11:38:31 &hellip; <a href=\"https:\/\/blogs.gentoo.org\/ago\/2016\/02\/16\/portage-utils-heap-based-buffer-overflow-in-qlop-c\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":140,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false,"jetpack_publicize_feature_enabled":true},"categories":[12,10],"tags":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2EaBc-5F","_links":{"self":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/351"}],"collection":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/users\/140"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/comments?post=351"}],"version-history":[{"count":10,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/351\/revisions"}],"predecessor-version":[{"id":394,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/351\/revisions\/394"}],"wp:attachment":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/media?parent=351"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/categories?post=351"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/tags?post=351"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}