forked from Minki/linux
3d6e48f433
When running a 31-bit ptrace, on either an s390 or s390x kernel, reads and writes into a padding area in struct user_regs_struct32 will result in a kernel panic. This is also known as CVE-2008-1514. Test case available here: http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/tests/ptrace-tests/tests/user-area-padding.c?cvsroot=systemtap Steps to reproduce: 1) wget the above 2) gcc -o user-area-padding-31bit user-area-padding.c -Wall -ggdb2 -D_GNU_SOURCE -m31 3) ./user-area-padding-31bit <panic> Test status ----------- Without patch, both s390 and s390x kernels panic. With patch, the test case, as well as the gdb testsuite, pass without incident, padding area reads returning zero, writes ignored. Nb: original version returned -EINVAL on write attempts, which broke the gdb test and made the test case slightly unhappy, Jan Kratochvil suggested the change to return 0 on write attempts. Signed-off-by: Jarod Wilson <jarod@redhat.com> Tested-by: Jan Kratochvil <jan.kratochvil@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
85 lines
2.4 KiB
C
85 lines
2.4 KiB
C
#ifndef _PTRACE32_H
|
|
#define _PTRACE32_H
|
|
|
|
#include "compat_linux.h" /* needed for psw_compat_t */
|
|
|
|
typedef struct {
|
|
__u32 cr[3];
|
|
} per_cr_words32;
|
|
|
|
typedef struct {
|
|
__u16 perc_atmid; /* 0x096 */
|
|
__u32 address; /* 0x098 */
|
|
__u8 access_id; /* 0x0a1 */
|
|
} per_lowcore_words32;
|
|
|
|
typedef struct {
|
|
union {
|
|
per_cr_words32 words;
|
|
} control_regs;
|
|
/*
|
|
* Use these flags instead of setting em_instruction_fetch
|
|
* directly they are used so that single stepping can be
|
|
* switched on & off while not affecting other tracing
|
|
*/
|
|
unsigned single_step : 1;
|
|
unsigned instruction_fetch : 1;
|
|
unsigned : 30;
|
|
/*
|
|
* These addresses are copied into cr10 & cr11 if single
|
|
* stepping is switched off
|
|
*/
|
|
__u32 starting_addr;
|
|
__u32 ending_addr;
|
|
union {
|
|
per_lowcore_words32 words;
|
|
} lowcore;
|
|
} per_struct32;
|
|
|
|
struct user_regs_struct32
|
|
{
|
|
psw_compat_t psw;
|
|
u32 gprs[NUM_GPRS];
|
|
u32 acrs[NUM_ACRS];
|
|
u32 orig_gpr2;
|
|
/* nb: there's a 4-byte hole here */
|
|
s390_fp_regs fp_regs;
|
|
/*
|
|
* These per registers are in here so that gdb can modify them
|
|
* itself as there is no "official" ptrace interface for hardware
|
|
* watchpoints. This is the way intel does it.
|
|
*/
|
|
per_struct32 per_info;
|
|
u32 ieee_instruction_pointer;
|
|
/* Used to give failing instruction back to user for ieee exceptions */
|
|
};
|
|
|
|
struct user32 {
|
|
/* We start with the registers, to mimic the way that "memory"
|
|
is returned from the ptrace(3,...) function. */
|
|
struct user_regs_struct32 regs; /* Where the registers are actually stored */
|
|
/* The rest of this junk is to help gdb figure out what goes where */
|
|
u32 u_tsize; /* Text segment size (pages). */
|
|
u32 u_dsize; /* Data segment size (pages). */
|
|
u32 u_ssize; /* Stack segment size (pages). */
|
|
u32 start_code; /* Starting virtual address of text. */
|
|
u32 start_stack; /* Starting virtual address of stack area.
|
|
This is actually the bottom of the stack,
|
|
the top of the stack is always found in the
|
|
esp register. */
|
|
s32 signal; /* Signal that caused the core dump. */
|
|
u32 u_ar0; /* Used by gdb to help find the values for */
|
|
/* the registers. */
|
|
u32 magic; /* To uniquely identify a core file */
|
|
char u_comm[32]; /* User command that was responsible */
|
|
};
|
|
|
|
typedef struct
|
|
{
|
|
__u32 len;
|
|
__u32 kernel_addr;
|
|
__u32 process_addr;
|
|
} ptrace_area_emu31;
|
|
|
|
#endif /* _PTRACE32_H */
|