| Message ID | 20151226231327.GA18682@altlinux.org |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index 30e7ddb..c690c8e 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -413,15 +413,15 @@ out: SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality) { - int ret; + long ret; if (personality(current->personality) == PER_LINUX32 && personality(personality) == PER_LINUX) personality |= PER_LINUX32; ret = sys_personality(personality); if (personality(ret) == PER_LINUX32) ret &= ~PER_LINUX32; return ret; }
The value returned by sys_personality has type "long int". It is saved to a variable of type "int", which is not a problem yet because the type of task_struct->pesonality is "unsigned int". The problem is the sign extension from "int" to "long int" that happens on return from sys_sparc64_personality. For example, a userspace call personality((unsigned) -EINVAL) will result to any subsequent personality call, including absolutely harmless read-only personality(0xffffffff) call, failing with errno set to EINVAL. Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Cc: <stable@vger.kernel.org> --- arch/sparc/kernel/sys_sparc_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)