From: Dmitry V. Levin Date: Sat, 26 Dec 2015 23:13:27 +0000 (+0300) Subject: sparc64: fix incorrect sign extension in sys_sparc64_personality X-Git-Tag: v4.1.12-92~198^2~3 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=8d7598b43c2f114c84ab10664f3e01d320f21b51;p=users%2Fjedix%2Flinux-maple.git sparc64: fix incorrect sign extension in sys_sparc64_personality 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 Cc: Signed-off-by: David S. Miller (cherry picked from commit 525fd5a94e1be0776fa652df5c687697db508c91) Signed-off-by: Allen Pais --- diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index ca709ef1206ea..155f86892dc92 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -413,7 +413,7 @@ out: SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality) { - int ret; + long ret; if (personality(current->personality) == PER_LINUX32 && personality(personality) == PER_LINUX)