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charset="UTF-8" Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Wed, Jul 17, 2019 at 1:09 PM Mike Rapoport wrote: > > On Mon, Jun 24, 2019 at 06:51:21PM +0100, Catalin Marinas wrote: > > On Mon, Jun 24, 2019 at 04:32:53PM +0200, Andrey Konovalov wrote: > > > This patch is a part of a series that extends kernel ABI to allow to pass > > > tagged user pointers (with the top byte set to something else other than > > > 0x00) as syscall arguments. > > > > > > userfaultfd code use provided user pointers for vma lookups, which can > > > only by done with untagged pointers. > > > > > > Untag user pointers in validate_range(). > > > > > > Reviewed-by: Vincenzo Frascino > > > Reviewed-by: Catalin Marinas > > > Reviewed-by: Kees Cook > > > Signed-off-by: Andrey Konovalov > > > --- > > > fs/userfaultfd.c | 22 ++++++++++++---------- > > > 1 file changed, 12 insertions(+), 10 deletions(-) > > > > Same here, it needs an ack from Al Viro. > > The userfault patches usually go via -mm tree, not sure if Al looks at them :) Ah, OK, I guess than Andrew will take a look at them when merging. > > FWIW, you can add > > Reviewed-by: Mike Rapoport I will, thanks! > > > > diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c > > > index ae0b8b5f69e6..c2be36a168ca 100644 > > > --- a/fs/userfaultfd.c > > > +++ b/fs/userfaultfd.c > > > @@ -1261,21 +1261,23 @@ static __always_inline void wake_userfault(struct userfaultfd_ctx *ctx, > > > } > > > > > > static __always_inline int validate_range(struct mm_struct *mm, > > > - __u64 start, __u64 len) > > > + __u64 *start, __u64 len) > > > { > > > __u64 task_size = mm->task_size; > > > > > > - if (start & ~PAGE_MASK) > > > + *start = untagged_addr(*start); > > > + > > > + if (*start & ~PAGE_MASK) > > > return -EINVAL; > > > if (len & ~PAGE_MASK) > > > return -EINVAL; > > > if (!len) > > > return -EINVAL; > > > - if (start < mmap_min_addr) > > > + if (*start < mmap_min_addr) > > > return -EINVAL; > > > - if (start >= task_size) > > > + if (*start >= task_size) > > > return -EINVAL; > > > - if (len > task_size - start) > > > + if (len > task_size - *start) > > > return -EINVAL; > > > return 0; > > > } > > > @@ -1325,7 +1327,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, > > > goto out; > > > } > > > > > > - ret = validate_range(mm, uffdio_register.range.start, > > > + ret = validate_range(mm, &uffdio_register.range.start, > > > uffdio_register.range.len); > > > if (ret) > > > goto out; > > > @@ -1514,7 +1516,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx, > > > if (copy_from_user(&uffdio_unregister, buf, sizeof(uffdio_unregister))) > > > goto out; > > > > > > - ret = validate_range(mm, uffdio_unregister.start, > > > + ret = validate_range(mm, &uffdio_unregister.start, > > > uffdio_unregister.len); > > > if (ret) > > > goto out; > > > @@ -1665,7 +1667,7 @@ static int userfaultfd_wake(struct userfaultfd_ctx *ctx, > > > if (copy_from_user(&uffdio_wake, buf, sizeof(uffdio_wake))) > > > goto out; > > > > > > - ret = validate_range(ctx->mm, uffdio_wake.start, uffdio_wake.len); > > > + ret = validate_range(ctx->mm, &uffdio_wake.start, uffdio_wake.len); > > > if (ret) > > > goto out; > > > > > > @@ -1705,7 +1707,7 @@ static int userfaultfd_copy(struct userfaultfd_ctx *ctx, > > > sizeof(uffdio_copy)-sizeof(__s64))) > > > goto out; > > > > > > - ret = validate_range(ctx->mm, uffdio_copy.dst, uffdio_copy.len); > > > + ret = validate_range(ctx->mm, &uffdio_copy.dst, uffdio_copy.len); > > > if (ret) > > > goto out; > > > /* > > > @@ -1761,7 +1763,7 @@ static int userfaultfd_zeropage(struct userfaultfd_ctx *ctx, > > > sizeof(uffdio_zeropage)-sizeof(__s64))) > > > goto out; > > > > > > - ret = validate_range(ctx->mm, uffdio_zeropage.range.start, > > > + ret = validate_range(ctx->mm, &uffdio_zeropage.range.start, > > > uffdio_zeropage.range.len); > > > if (ret) > > > goto out; > > > -- > > > 2.22.0.410.gd8fdbe21b5-goog > > -- > Sincerely yours, > Mike. >