You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

124 lines
3.7 KiB

diff --git a/src/elfclass.h b/src/elfclass.h
index 010958a..0826ce3 100644
--- a/src/elfclass.h
+++ b/src/elfclass.h
@@ -35,10 +35,12 @@
switch (type) {
#ifdef ELFCORE
case ET_CORE:
+ phnum = elf_getu16(swap, elfhdr.e_phnum);
+ if (phnum > MAX_PHNUM)
+ return toomany(ms, "program", phnum);
flags |= FLAGS_IS_CORE;
if (dophn_core(ms, clazz, swap, fd,
- (off_t)elf_getu(swap, elfhdr.e_phoff),
- elf_getu16(swap, elfhdr.e_phnum),
+ (off_t)elf_getu(swap, elfhdr.e_phoff), phnum,
(size_t)elf_getu16(swap, elfhdr.e_phentsize),
fsize, &flags) == -1)
return -1;
@@ -46,18 +48,24 @@
#endif
case ET_EXEC:
case ET_DYN:
+ phnum = elf_getu16(swap, elfhdr.e_phnum);
+ if (phnum > MAX_PHNUM)
+ return toomany(ms, "program", phnum);
+ shnum = elf_getu16(swap, elfhdr.e_shnum);
+ if (shnum > MAX_SHNUM)
+ return toomany(ms, "section", shnum);
if (dophn_exec(ms, clazz, swap, fd,
- (off_t)elf_getu(swap, elfhdr.e_phoff),
- elf_getu16(swap, elfhdr.e_phnum),
+ (off_t)elf_getu(swap, elfhdr.e_phoff), phnum,
(size_t)elf_getu16(swap, elfhdr.e_phentsize),
- fsize, &flags, elf_getu16(swap, elfhdr.e_shnum))
- == -1)
+ fsize, &flags, shnum) == -1)
return -1;
/*FALLTHROUGH*/
case ET_REL:
+ shnum = elf_getu16(swap, elfhdr.e_shnum);
+ if (shnum > MAX_SHNUM)
+ return toomany(ms, "section", shnum);
if (doshn(ms, clazz, swap, fd,
- (off_t)elf_getu(swap, elfhdr.e_shoff),
- elf_getu16(swap, elfhdr.e_shnum),
+ (off_t)elf_getu(swap, elfhdr.e_shoff), shnum,
(size_t)elf_getu16(swap, elfhdr.e_shentsize),
fsize, &flags, elf_getu16(swap, elfhdr.e_machine),
(int)elf_getu16(swap, elfhdr.e_shstrndx)) == -1)
diff --git a/src/readelf.c b/src/readelf.c
index de016b5..1f4d1f4 100644
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -60,6 +60,18 @@ private uint16_t getu16(int, uint16_t);
private uint32_t getu32(int, uint32_t);
private uint64_t getu64(int, uint64_t);
+#define MAX_PHNUM 2048
+#define MAX_SHNUM 32768
+
+private int
+toomany(struct magic_set *ms, const char *name, uint16_t num)
+{
+ if (file_printf(ms, ", too many %s header sections (%u)", name, num
+ ) == -1)
+ return -1;
+ return 0;
+}
+
private uint16_t
getu16(int swap, uint16_t value)
{
@@ -388,13 +400,13 @@ donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
if (namesz & 0x80000000) {
(void)file_printf(ms, ", bad note name size 0x%lx",
(unsigned long)namesz);
- return offset;
+ return 0;
}
if (descsz & 0x80000000) {
(void)file_printf(ms, ", bad note description size 0x%lx",
(unsigned long)descsz);
- return offset;
+ return 0;
}
@@ -851,6 +863,7 @@ doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
Elf32_Shdr sh32;
Elf64_Shdr sh64;
int stripped = 1;
+ size_t nbadcap = 0;
void *nbuf;
off_t noff, coff, name_off;
uint64_t cap_hw1 = 0; /* SunOS 5.x hardware capabilites */
@@ -928,6 +941,8 @@ doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
free(nbuf);
break;
case SHT_SUNW_cap:
+ if (nbadcap > 5)
+ break;
if (lseek(fd, xsh_offset, SEEK_SET) == (off_t)-1) {
file_badseek(ms);
return -1;
@@ -963,6 +978,8 @@ doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
(unsigned long long)xcap_tag,
(unsigned long long)xcap_val) == -1)
return -1;
+ if (nbadcap++ > 2)
+ coff = xsh_size;
break;
}
}
@@ -1142,7 +1159,7 @@ file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
int flags = 0;
Elf32_Ehdr elf32hdr;
Elf64_Ehdr elf64hdr;
- uint16_t type;
+ uint16_t type, phnum, shnum;
if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
return 0;