Messages in this thread Patch in this message | | | Date | Wed, 1 Aug 2012 20:48:48 +0200 (CEST) | From | Jiri Kosina <> | Subject | [PATCH] [S390] do not clobber personality flags in sys_32_personality() |
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There are multiple errors in how sys_32_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 bytes covered by PER_MASK. Fix the second one by setting only the bits that should be set, instead of overwriting the whole value.
Signed-off-by: Jiri Kosina <jkosina@suse.cz> --- arch/s390/kernel/sys_s390.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/arch/s390/kernel/sys_s390.c b/arch/s390/kernel/sys_s390.c index b4a29ee..6afcfd9 100644 --- a/arch/s390/kernel/sys_s390.c +++ b/arch/s390/kernel/sys_s390.c @@ -81,11 +81,12 @@ SYSCALL_DEFINE1(s390_personality, unsigned int, personality) { unsigned 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; } -- Jiri Kosina SUSE Labs
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