From b1e542206bed371e6c191008ad8b2b7d1f0cba151d67852f209b86cabe0c5989 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 8 Aug 2017 09:26:19 +0000 Subject: [PATCH] Accepting request 515150 from home:tiwai:branches:multimedia:libs - Fix Heap-based Buffer Overflow in the psf_binheader_writef (CVE-2017-12562, bsc#1052476): 0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch OBS-URL: https://build.opensuse.org/request/show/515150 OBS-URL: https://build.opensuse.org/package/show/multimedia:libs/libsndfile?expand=0&rev=62 --- ...-heap-buffer-overflows-when-writing-.patch | 86 +++++++++++++++++++ libsndfile.changes | 7 ++ libsndfile.spec | 2 + 3 files changed, 95 insertions(+) create mode 100644 0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch diff --git a/0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch b/0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch new file mode 100644 index 0000000..f90f9a3 --- /dev/null +++ b/0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch @@ -0,0 +1,86 @@ +From cf7a8182c2642c50f1cf90dddea9ce96a8bad2e8 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?J=C3=B6rn=20Heusipp?= +Date: Wed, 14 Jun 2017 12:25:40 +0200 +Subject: [PATCH] src/common.c: Fix heap buffer overflows when writing strings + in binheader + +Fixes the following problems: + 1. Case 's' only enlarges the buffer by 16 bytes instead of size bytes. + 2. psf_binheader_writef() enlarges the header buffer (if needed) prior to the + big switch statement by an amount (16 bytes) which is enough for all cases + where only a single value gets added. Cases 's', 'S', 'p' however + additionally write an arbitrary length block of data and again enlarge the + buffer to the required amount. However, the required space calculation does + not take into account the size of the length field which gets output before + the data. + 3. Buffer size requirement calculation in case 'S' does not account for the + padding byte ("size += (size & 1) ;" happens after the calculation which + uses "size"). + 4. Case 'S' can overrun the header buffer by 1 byte when no padding is + involved + ("memcpy (&(psf->header.ptr [psf->header.indx]), strptr, size + 1) ;" while + the buffer is only guaranteed to have "size" space available). + 5. "psf->header.ptr [psf->header.indx] = 0 ;" in case 'S' always writes 1 byte + beyond the space which is guaranteed to be allocated in the header buffer. + 6. Case 's' can overrun the provided source string by 1 byte if padding is + involved ("memcpy (&(psf->header.ptr [psf->header.indx]), strptr, size) ;" + where "size" is "strlen (strptr) + 1" (which includes the 0 terminator, + plus optionally another 1 which is padding and not guaranteed to be + readable via the source string pointer). + +Closes: https://github.com/erikd/libsndfile/issues/292 +--- + src/common.c | 15 +++++++-------- + 1 file changed, 7 insertions(+), 8 deletions(-) + +--- a/src/common.c ++++ b/src/common.c +@@ -675,16 +675,16 @@ psf_binheader_writef (SF_PRIVATE *psf, c + /* Write a C string (guaranteed to have a zero terminator). */ + strptr = va_arg (argptr, char *) ; + size = strlen (strptr) + 1 ; +- size += (size & 1) ; + +- if (psf->header.indx + (sf_count_t) size >= psf->header.len && psf_bump_header_allocation (psf, 16)) ++ if (psf->header.indx + 4 + (sf_count_t) size + (sf_count_t) (size & 1) > psf->header.len && psf_bump_header_allocation (psf, 4 + size + (size & 1))) + return count ; + + if (psf->rwf_endian == SF_ENDIAN_BIG) +- header_put_be_int (psf, size) ; ++ header_put_be_int (psf, size + (size & 1)) ; + else +- header_put_le_int (psf, size) ; ++ header_put_le_int (psf, size + (size & 1)) ; + memcpy (&(psf->header.ptr [psf->header.indx]), strptr, size) ; ++ size += (size & 1) ; + psf->header.indx += size ; + psf->header.ptr [psf->header.indx - 1] = 0 ; + count += 4 + size ; +@@ -697,16 +697,15 @@ psf_binheader_writef (SF_PRIVATE *psf, c + */ + strptr = va_arg (argptr, char *) ; + size = strlen (strptr) ; +- if (psf->header.indx + (sf_count_t) size > psf->header.len && psf_bump_header_allocation (psf, size)) ++ if (psf->header.indx + 4 + (sf_count_t) size + (sf_count_t) (size & 1) > psf->header.len && psf_bump_header_allocation (psf, 4 + size + (size & 1))) + return count ; + if (psf->rwf_endian == SF_ENDIAN_BIG) + header_put_be_int (psf, size) ; + else + header_put_le_int (psf, size) ; +- memcpy (&(psf->header.ptr [psf->header.indx]), strptr, size + 1) ; ++ memcpy (&(psf->header.ptr [psf->header.indx]), strptr, size + (size & 1)) ; + size += (size & 1) ; + psf->header.indx += size ; +- psf->header.ptr [psf->header.indx] = 0 ; + count += 4 + size ; + break ; + +@@ -718,7 +717,7 @@ psf_binheader_writef (SF_PRIVATE *psf, c + size = (size & 1) ? size : size + 1 ; + size = (size > 254) ? 254 : size ; + +- if (psf->header.indx + (sf_count_t) size > psf->header.len && psf_bump_header_allocation (psf, size)) ++ if (psf->header.indx + 1 + (sf_count_t) size > psf->header.len && psf_bump_header_allocation (psf, 1 + size)) + return count ; + + header_put_byte (psf, size) ; diff --git a/libsndfile.changes b/libsndfile.changes index 770c7a9..28c422f 100644 --- a/libsndfile.changes +++ b/libsndfile.changes @@ -1,3 +1,10 @@ +------------------------------------------------------------------- +Tue Aug 8 11:00:09 CEST 2017 - tiwai@suse.de + +- Fix Heap-based Buffer Overflow in the psf_binheader_writef + (CVE-2017-12562, bsc#1052476): + 0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch + ------------------------------------------------------------------- Tue Jun 13 08:36:52 CEST 2017 - tiwai@suse.de diff --git a/libsndfile.spec b/libsndfile.spec index cb29f88..f953521 100644 --- a/libsndfile.spec +++ b/libsndfile.spec @@ -32,6 +32,7 @@ Source3: baselibs.conf Patch1: 0001-FLAC-Fix-a-buffer-read-overrun.patch Patch2: 0002-src-flac.c-Fix-a-buffer-read-overflow.patch Patch10: 0010-src-aiff.c-Fix-a-buffer-read-overflow.patch +Patch20: 0020-src-common.c-Fix-heap-buffer-overflows-when-writing-.patch # PATCH-FIX-OPENSUSE Patch100: sndfile-ocloexec.patch BuildRequires: alsa-devel @@ -82,6 +83,7 @@ libsndfile library. %patch1 -p1 %patch2 -p1 %patch10 -p1 +%patch20 -p1 %patch100 -p1 %build