On 6/15/15 6:13 PM, Julian Calaby wrote:
Hi David, On Tue, Jun 16, 2015 at 6:15 AM, David Ahern <david.ahern@xxxxxxxxxx> wrote:Processes are getting killed (sigbus or segv) while walking userspace callchains when using perf. In some instances I have seen ufp = 0x7ff which does not seem like a proper stack address. This patch adds a function to run validity checks against the address before attempting the copy_from_user. The checks are copied from the x86 version as a start point with the addition of a 4-byte alignment check. Signed-off-by: David Ahern <david.ahern@xxxxxxxxxx> --- arch/sparc/include/asm/uaccess_64.h | 22 ++++++++++++++++++++++ arch/sparc/kernel/perf_event.c | 13 +++++++++++++ 2 files changed, 35 insertions(+) diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h index a35194b7dba0..ea6e9a20f3ff 100644 --- a/arch/sparc/include/asm/uaccess_64.h +++ b/arch/sparc/include/asm/uaccess_64.h @@ -49,6 +49,28 @@ do { \ __asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \ } while(0) +/* + * Test whether a block of memory is a valid user space address. + * Returns 0 if the range is valid, nonzero otherwise.Do you mean true / false here?
Yes. I literally copied and pasted from x86 code. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
