{"id":1684,"date":"2017-04-29T15:33:44","date_gmt":"2017-04-29T13:33:44","guid":{"rendered":"http:\/\/blogs.gentoo.org\/ago\/?p=1684"},"modified":"2017-05-01T13:23:27","modified_gmt":"2017-05-01T11:23:27","slug":"libsndfile-global-buffer-overflow-in-i2les_array-pcm-c","status":"publish","type":"post","link":"https:\/\/blogs.gentoo.org\/ago\/2017\/04\/29\/libsndfile-global-buffer-overflow-in-i2les_array-pcm-c\/","title":{"rendered":"libsndfile: global buffer overflow in i2les_array (pcm.c)"},"content":{"rendered":"<p><strong>Description<\/strong>:<br \/>\n<a href=\"http:\/\/www.mega-nerd.com\/libsndfile\">libsndfile<\/a> is a C library for reading and writing files containing sampled sound.<\/p>\n<p>The complete ASan output of the issue:<\/p>\n<pre><font size=\"2\"># sndfile-convert $FILE out.wav\r\n==27948==ERROR: AddressSanitizer: global-buffer-overflow on address 0x0000013cd13c at pc 0x7f59caaaaace bp 0x7ffcab360cf0 sp 0x7ffcab360ce8                                                                       \r\nREAD of size 4 at 0x0000013cd13c thread T0                                                                                                                                                                        \r\n    #0 0x7f59caaaaacd in i2les_array \/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/src\/pcm.c:670:15                                                                                            \r\n    #1 0x7f59caaaaacd in pcm_write_i2les \/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/src\/pcm.c:1696                                                                                          \r\n    #2 0x7f59ca7bf831 in sf_writef_int \/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/src\/sndfile.c:2342:10                                                                                     \r\n    #3 0x514b70 in sfe_copy_data_int \/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/programs\/common.c:88:3                                                                                      \r\n    #4 0x5138d1 in main \/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/programs\/sndfile-convert.c:340:3                                                                                         \r\n    #5 0x7f59c974178f in __libc_start_main \/tmp\/portage\/sys-libs\/glibc-2.23-r3\/work\/glibc-2.23\/csu\/..\/csu\/libc-start.c:289                                                                                        \r\n    #6 0x419e18 in _init (\/usr\/bin\/sndfile-convert+0x419e18)                                                                                                                                                      \r\n                                                                                                                                                                                                                  \r\n0x0000013cd13c is located 4092 bytes to the right of global variable 'data' defined in '\/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/programs\/common.c:80:14' (0x13c8140) of size 16384       \r\nSUMMARY: AddressSanitizer: global-buffer-overflow \/tmp\/portage\/media-libs\/libsndfile-1.0.28\/work\/libsndfile-1.0.28\/src\/pcm.c:670:15 in i2les_array                                                                \r\nShadow bytes around the buggy address:                                                                                                                                                                            \r\n  0x0000802719d0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9                                                                                                                                                 \r\n  0x0000802719e0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9                                                                                                                                                 \r\n  0x0000802719f0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9                                                                                                                                                 \r\n  0x000080271a00: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9                                                                                                                                                 \r\n  0x000080271a10: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9                                                                                                                                                 \r\n=&gt;0x000080271a20: f9 f9 f9 f9 f9 f9 f9[f9]00 00 00 00 00 00 00 00                                                                                                                                                 \r\n  0x000080271a30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00                                                                                                                                                 \r\n  0x000080271a40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00                                                                                                                                                 \r\n  0x000080271a50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00                                                                                                                                                 \r\n  0x000080271a60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00                                                                                                                                                 \r\n  0x000080271a70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00                                                                                                                                                 \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  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 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==27948==ABORTING\r\n<\/font><\/pre>\n<p><strong>Affected version:<\/strong><br \/>\n1.0.28<\/p>\n<p><strong>Fixed version:<\/strong><br \/>\nN\/A<\/p>\n<p><strong>Commit fix:<\/strong><br \/>\n<a href=\"https:\/\/github.com\/erikd\/libsndfile\/commit\/fd0484aba8e51d16af1e3a880f9b8b857b385eb3\">https:\/\/github.com\/erikd\/libsndfile\/commit\/fd0484aba8e51d16af1e3a880f9b8b857b385eb3<\/a><\/p>\n<p><strong>Credit:<\/strong><br \/>\nThis bug was discovered by Agostino Sarubbo of Gentoo.<\/p>\n<p><strong>CVE:<\/strong><br \/>\nCVE-2017-8365<\/p>\n<p><strong>Reproducer:<\/strong><br \/>\n<a href=\"https:\/\/github.com\/asarubbo\/poc\/blob\/master\/00263-libsndfile-globaloverflow-i2les_array\">https:\/\/github.com\/asarubbo\/poc\/blob\/master\/00263-libsndfile-globaloverflow-i2les_array<\/a><\/p>\n<p><strong>Timeline:<\/strong><br \/>\n2017-04-11: bug discovered and reported to upstream<br \/>\n2017-04-12: upstream released a patch<br \/>\n2017-04-29: blog post about the issue<br \/>\n2017-04-30: CVE assigned<\/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=\"oMPRpicGLA\" class=\"wp-embedded-content\"><p><a href=\"http:\/\/blogs.gentoo.org\/ago\/2017\/04\/29\/libsndfile-global-buffer-overflow-in-i2les_array-pcm-c\/\">libsndfile: global buffer overflow in i2les_array (pcm.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\/2017\/04\/29\/libsndfile-global-buffer-overflow-in-i2les_array-pcm-c\/embed\/#?secret=oMPRpicGLA\" data-secret=\"oMPRpicGLA\" width=\"600\" height=\"338\" title=\"&#8220;libsndfile: global buffer overflow in i2les_array (pcm.c)&#8221; &#8212; agostino&#039;s blog\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Description: libsndfile is a C library for reading and writing files containing sampled sound. The complete ASan output of the issue: # sndfile-convert $FILE out.wav ==27948==ERROR: AddressSanitizer: global-buffer-overflow on address 0x0000013cd13c at pc 0x7f59caaaaace bp 0x7ffcab360cf0 sp 0x7ffcab360ce8 READ of &hellip; <a href=\"https:\/\/blogs.gentoo.org\/ago\/2017\/04\/29\/libsndfile-global-buffer-overflow-in-i2les_array-pcm-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-ra","_links":{"self":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/1684"}],"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=1684"}],"version-history":[{"count":3,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/1684\/revisions"}],"predecessor-version":[{"id":1734,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/posts\/1684\/revisions\/1734"}],"wp:attachment":[{"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/media?parent=1684"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/categories?post=1684"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.gentoo.org\/ago\/wp-json\/wp\/v2\/tags?post=1684"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}