diff options
| author | Dave Martin <Dave.Martin@arm.com> | 2017-03-27 15:10:54 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-31 09:49:53 +0200 |
| commit | e1dc8904b33b8c01f22d904fed4cb5f2060f5da3 (patch) | |
| tree | 59110962d9aaab7674d09855919cd3d01227423b | |
| parent | 6e174bbd0631865acc193804fa4043852f3198c5 (diff) | |
h8300/ptrace: Fix incorrect register transfer count
commit 502585c7555083d4a949c08350306b9ec196779e upstream.
regs_set() and regs_get() are vulnerable to an off-by-1 buffer overrun
if CONFIG_CPU_H8S is set, since this adds an extra entry to
register_offset[] but not to user_regs_struct.
So, iterate over user_regs_struct based on its actual size, not based on
the length of register_offset[].
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/h8300/kernel/ptrace.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/h8300/kernel/ptrace.c b/arch/h8300/kernel/ptrace.c index 92075544a19a..0dc1c8f622bc 100644 --- a/arch/h8300/kernel/ptrace.c +++ b/arch/h8300/kernel/ptrace.c @@ -95,7 +95,8 @@ static int regs_get(struct task_struct *target, long *reg = (long *)®s; /* build user regs in buffer */ - for (r = 0; r < ARRAY_SIZE(register_offset); r++) + BUILD_BUG_ON(sizeof(regs) % sizeof(long) != 0); + for (r = 0; r < sizeof(regs) / sizeof(long); r++) *reg++ = h8300_get_reg(target, r); return user_regset_copyout(&pos, &count, &kbuf, &ubuf, @@ -113,7 +114,8 @@ static int regs_set(struct task_struct *target, long *reg; /* build user regs in buffer */ - for (reg = (long *)®s, r = 0; r < ARRAY_SIZE(register_offset); r++) + BUILD_BUG_ON(sizeof(regs) % sizeof(long) != 0); + for (reg = (long *)®s, r = 0; r < sizeof(regs) / sizeof(long); r++) *reg++ = h8300_get_reg(target, r); ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, @@ -122,7 +124,7 @@ static int regs_set(struct task_struct *target, return ret; /* write back to pt_regs */ - for (reg = (long *)®s, r = 0; r < ARRAY_SIZE(register_offset); r++) + for (reg = (long *)®s, r = 0; r < sizeof(regs) / sizeof(long); r++) h8300_put_reg(target, r, *reg++); return 0; } |