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Revision 1fb844961818ce94e782acf6a96b92dc2303553b authored by Alexey Dobriyan on 26 January 2007, 08:57:16 UTC, committed by Linus Torvalds on 26 January 2007, 21:51:00 UTC 
[PATCH] core-dumping unreadable binaries via PT_INTERP
 
Proposed patch to fix #5 in
http://www.isec.pl/vulnerabilities/isec-0017-binfmt_elf.txt
aka
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2004-1073

To reproduce, do
* grab poc at the end of advisory.
* add line "eph.p_memsz = 4096;" after "eph.p_filesz = 4096;"
  where first "4096" is something equal to or greater than 4096.
* ./poc /usr/bin/sudo && ls -l

Here I get with 2.6.20-rc5:

 -rw------- 1 ad   ad   102400 2007-01-15 19:17 core
 ---s--x--x 2 root root 101820 2007-01-15 19:15 /usr/bin/sudo

Check for MAY_READ like binfmt_misc.c does.

Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent c20086d
Raw File
audit.c 
#include <linux/init.h>
#include <linux/types.h>
#include <linux/audit.h>
#include <asm/unistd.h>

static unsigned dir_class[] = {
#include <asm-generic/audit_dir_write.h>
~0U
};

static unsigned read_class[] = {
#include <asm-generic/audit_read.h>
~0U
};

static unsigned write_class[] = {
#include <asm-generic/audit_write.h>
~0U
};

static unsigned chattr_class[] = {
#include <asm-generic/audit_change_attr.h>
~0U
};

int audit_classify_syscall(int abi, unsigned syscall)
{
	switch(syscall) {
	case __NR_open:
		return 2;
#ifdef __NR_openat
	case __NR_openat:
		return 3;
#endif
#ifdef __NR_socketcall
	case __NR_socketcall:
		return 4;
#endif
	case __NR_execve:
		return 5;
	default:
		return 0;
	}
}

static int __init audit_classes_init(void)
{
	audit_register_class(AUDIT_CLASS_WRITE, write_class);
	audit_register_class(AUDIT_CLASS_READ, read_class);
	audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class);
	audit_register_class(AUDIT_CLASS_CHATTR, chattr_class);
	return 0;
}

__initcall(audit_classes_init);
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