From patchwork Wed Aug 1 20:05:55 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: sparc64: do not clobber personality flags in sys_sparc64_personality() Date: Wed, 01 Aug 2012 10:05:55 -0000 From: Jiri Kosina X-Patchwork-Id: 174587 Message-Id: To: "David S. Miller" Cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org There are multiple errors in how sys_sparc64_personality() handles personality flags stored in top three bytes. - directly comparing current->personality against PER_LINUX32 doesn't work in cases when any of the personality flags stored in the top three bytes are used. - directly forcefully setting personality to PER_LINUX32 or PER_LINUX discards any flags stored in the top three bytes Fix the first one by properly using personality() macro to compare only PER_MASK bytes. Fix the second one by setting only the bits that should be set, instead of overwriting the whole value. Signed-off-by: Jiri Kosina --- Found accidentally. Untested, I don't have the hardware. arch/sparc/kernel/sys_sparc_64.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index 0dc1f57..d48a364 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -502,12 +502,12 @@ SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality) { int ret; - if (current->personality == PER_LINUX32 && - personality == PER_LINUX) - personality = PER_LINUX32; + if (personality(current->personality) == PER_LINUX32 && + personality(personality) == PER_LINUX) + personality &= ~PER_LINUX | PER_LINUX32; ret = sys_personality(personality); - if (ret == PER_LINUX32) - ret = PER_LINUX; + if (personality(ret) == PER_LINUX32) + ret &= ~PER_LINUX32 | PER_LINUX; return ret; }