Commit-ID: 722d0172377a5697919b9f7e5beb95165b1dec4e Gitweb: http://git.kernel.org/tip/722d0172377a5697919b9f7e5beb95165b1dec4e Author: Andi Kleen <andi@xxxxxxxxxxxxxx> AuthorDate: Tue, 8 Dec 2009 13:19:42 +0100 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Tue, 8 Dec 2009 14:59:36 +0100 futex: Take mmap_sem for get_user_pages in fault_in_user_writeable get_user_pages() must be called with mmap_sem held. Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxx Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxx> Cc: Nick Piggin <npiggin@xxxxxxx> Cc: Darren Hart <dvhltc@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> LKML-Reference: <20091208121942.GA21298@xxxxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- kernel/futex.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff --git a/kernel/futex.c b/kernel/futex.c index fb65e82..d73ef1f 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -304,8 +304,14 @@ void put_futex_key(int fshared, union futex_key *key) */ static int fault_in_user_writeable(u32 __user *uaddr) { - int ret = get_user_pages(current, current->mm, (unsigned long)uaddr, - 1, 1, 0, NULL, NULL); + struct mm_struct *mm = current->mm; + int ret; + + down_read(&mm->mmap_sem); + ret = get_user_pages(current, mm, (unsigned long)uaddr, + 1, 1, 0, NULL, NULL); + up_read(&mm->mmap_sem); + return ret < 0 ? ret : 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html