gnu: upx: Fix CVE-2017-15056.

* gnu/packages/patches/upx-protect-against-bad-crafted-input.patch: New file.
* gnu/packages/compression.scm (upx)[source]: Use it.
* gnu/local.mk (dist_patch_DATA): Add it.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

1 files changed, 96 insertions, 0 deletions

diff --git a/gnu/packages/patches/upx-fix-CVE-2017-15056.patch b/gnu/packages/patches/upx-fix-CVE-2017-15056.patch
new file mode 100644
index 0000000000..525980e73e
--- /dev/null
+++ b/gnu/packages/patches/upx-fix-CVE-2017-15056.patch
@@ -0,0 +1,96 @@
+From 3e0c2966dffb5dadb512a476ef4be3d0cc51c2be Mon Sep 17 00:00:00 2001
+From: Pierre Neidhardt <ambrevar@gmail.com>
+Date: Sat, 16 Jun 2018 16:35:00 +0200
+Subject: [PATCH] Protect against bad crafted input
+
+Also check for wrap-around when checking oversize involving e_shoff and e_shnum.
+
+raised by https://github.com/upx/upx/pull/190
+	modified:   p_lx_elf.cpp
+---
+ src/p_lx_elf.cpp | 30 ++++++++++++++++++++++++++++++
+ 1 file changed, 30 insertions(+)
+
+diff --git a/src/p_lx_elf.cpp b/src/p_lx_elf.cpp
+index 822a7652..41e805ee 100644
+--- a/src/p_lx_elf.cpp
++++ b/src/p_lx_elf.cpp
+@@ -235,8 +235,17 @@ PackLinuxElf32::PackLinuxElf32help1(InputFile *f)
+         sz_phdrs = 0;
+         return;
+     }
++    if (0==e_phnum) throwCantUnpack("0==e_phnum");
+     e_phoff = get_te32(&ehdri.e_phoff);
++    unsigned const last_Phdr = e_phoff + e_phnum * sizeof(Elf32_Phdr);
++    if (last_Phdr < e_phoff || (unsigned long)file_size < last_Phdr) {
++        throwCantUnpack("bad e_phoff");
++    }
+     e_shoff = get_te32(&ehdri.e_shoff);
++    unsigned const last_Shdr = e_shoff + e_shnum * sizeof(Elf32_Shdr);
++    if (last_Shdr < e_shoff || (unsigned long)file_size < last_Shdr) {
++        throwCantUnpack("bad e_shoff");
++    }
+     sz_phdrs = e_phnum * e_phentsize;
+ 
+     if (f && Elf32_Ehdr::ET_DYN!=e_type) {
+@@ -599,8 +608,17 @@ PackLinuxElf64::PackLinuxElf64help1(InputFile *f)
+         sz_phdrs = 0;
+         return;
+     }
++    if (0==e_phnum) throwCantUnpack("0==e_phnum");
+     e_phoff = get_te64(&ehdri.e_phoff);
++    upx_uint64_t const last_Phdr = e_phoff + e_phnum * sizeof(Elf64_Phdr);
++    if (last_Phdr < e_phoff || (unsigned long)file_size < last_Phdr) {
++        throwCantUnpack("bad e_phoff");
++    }
+     e_shoff = get_te64(&ehdri.e_shoff);
++    upx_uint64_t const last_Shdr = e_shoff + e_shnum * sizeof(Elf64_Shdr);
++    if (last_Shdr < e_shoff || (unsigned long)file_size < last_Shdr) {
++        throwCantUnpack("bad e_shoff");
++    }
+     sz_phdrs = e_phnum * e_phentsize;
+ 
+     if (f && Elf64_Ehdr::ET_DYN!=e_type) {
+@@ -3763,6 +3781,9 @@ void PackLinuxElf64::pack4(OutputFile *fo, Filter &ft)
+ 
+ void PackLinuxElf64::unpack(OutputFile *fo)
+ {
++    if (e_phoff != sizeof(Elf64_Ehdr)) {// Phdrs not contiguous with Ehdr
++        throwCantUnpack("bad e_phoff");
++    }
+     unsigned const c_phnum = get_te16(&ehdri.e_phnum);
+     upx_uint64_t old_data_off = 0;
+     upx_uint64_t old_data_len = 0;
+@@ -3828,6 +3849,9 @@ void PackLinuxElf64::unpack(OutputFile *fo)
+     unsigned total_out = 0;
+     unsigned c_adler = upx_adler32(NULL, 0);
+     unsigned u_adler = upx_adler32(NULL, 0);
++    if ((MAX_ELF_HDR - sizeof(Elf64_Ehdr))/sizeof(Elf64_Phdr) < u_phnum) {
++        throwCantUnpack("bad compressed e_phnum");
++    }
+ 
+     // Packed ET_EXE has no PT_DYNAMIC.
+     // Packed ET_DYN has original PT_DYNAMIC for info needed by rtld.
+@@ -4383,6 +4407,9 @@ Elf64_Sym const *PackLinuxElf64::elf_lookup(char const *name) const
+ 
+ void PackLinuxElf32::unpack(OutputFile *fo)
+ {
++    if (e_phoff != sizeof(Elf32_Ehdr)) {// Phdrs not contiguous with Ehdr
++        throwCantUnpack("bad e_phoff");
++    }
+     unsigned const c_phnum = get_te16(&ehdri.e_phnum);
+     unsigned old_data_off = 0;
+     unsigned old_data_len = 0;
+@@ -4449,6 +4476,9 @@ void PackLinuxElf32::unpack(OutputFile *fo)
+     unsigned total_out = 0;
+     unsigned c_adler = upx_adler32(NULL, 0);
+     unsigned u_adler = upx_adler32(NULL, 0);
++    if ((MAX_ELF_HDR - sizeof(Elf32_Ehdr))/sizeof(Elf32_Phdr) < u_phnum) {
++        throwCantUnpack("bad compressed e_phnum");
++    }
+ 
+     // Packed ET_EXE has no PT_DYNAMIC.
+     // Packed ET_DYN has original PT_DYNAMIC for info needed by rtld.
+-- 
+2.17.0
+