diff options
Diffstat (limited to 'user/libsndfile/CVE-2017-12562.patch')
| -rw-r--r-- | user/libsndfile/CVE-2017-12562.patch | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/user/libsndfile/CVE-2017-12562.patch b/user/libsndfile/CVE-2017-12562.patch new file mode 100644 index 000000000..f195e87e4 --- /dev/null +++ b/user/libsndfile/CVE-2017-12562.patch @@ -0,0 +1,88 @@ +From cf7a8182c2642c50f1cf90dddea9ce96a8bad2e8 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?J=C3=B6rn=20Heusipp?= <osmanx@problemloesungsmaschine.de> +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(-) + +diff --git a/src/common.c b/src/common.c +index 1a6204ca..6b2a2ee9 100644 +--- a/src/common.c ++++ b/src/common.c +@@ -681,16 +681,16 @@ psf_binheader_writef (SF_PRIVATE *psf, const char *format, ...) + /* 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 ; +@@ -703,16 +703,15 @@ psf_binheader_writef (SF_PRIVATE *psf, const char *format, ...) + */ + 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 ; + +@@ -724,7 +723,7 @@ psf_binheader_writef (SF_PRIVATE *psf, const char *format, ...) + 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) ; |