Subject: [merged] mm-shift-vm_grows-check-from-mmap_region-to-do_mmap_pgoff-v2.patch removed from -mm tree To: oleg@xxxxxxxxxx,hughd@xxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Thu, 12 Sep 2013 12:42:19 -0700 The patch titled Subject: mm: shift VM_GROWS* check from mmap_region() to do_mmap_pgoff() has been removed from the -mm tree. Its filename was mm-shift-vm_grows-check-from-mmap_region-to-do_mmap_pgoff-v2.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: mm: shift VM_GROWS* check from mmap_region() to do_mmap_pgoff() mmap() doesn't allow the non-anonymous mappings with VM_GROWS* bit set. In particular this means that mmap_region()->vma_merge(file, vm_flags) must always fail if "vm_flags & VM_GROWS" is set incorrectly. So it does not make sense to check VM_GROWS* after we already allocated the new vma, the only caller, do_mmap_pgoff(), which can pass this flag can do the check itself. And this looks a bit more correct, mmap_region() already unmapped the old mapping at this stage. But if mmap() is going to fail, it should avoid do_munmap() if possible. Note: we check VM_GROWS at the end to ensure that do_mmap_pgoff() won't return EINVAL in the case when it currently returns another error code. Many thanks to Hugh who nacked the buggy v1. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Acked-by: Hugh Dickins <hughd@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mmap.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff -puN mm/mmap.c~mm-shift-vm_grows-check-from-mmap_region-to-do_mmap_pgoff-v2 mm/mmap.c --- a/mm/mmap.c~mm-shift-vm_grows-check-from-mmap_region-to-do_mmap_pgoff-v2 +++ a/mm/mmap.c @@ -1302,6 +1302,8 @@ unsigned long do_mmap_pgoff(struct file if (!file->f_op || !file->f_op->mmap) return -ENODEV; + if (vm_flags & (VM_GROWSDOWN|VM_GROWSUP)) + return -EINVAL; break; default: @@ -1310,6 +1312,8 @@ unsigned long do_mmap_pgoff(struct file } else { switch (flags & MAP_TYPE) { case MAP_SHARED: + if (vm_flags & (VM_GROWSDOWN|VM_GROWSUP)) + return -EINVAL; /* * Ignore pgoff. */ @@ -1544,11 +1548,7 @@ munmap_back: vma->vm_pgoff = pgoff; INIT_LIST_HEAD(&vma->anon_vma_chain); - error = -EINVAL; /* when rejecting VM_GROWSDOWN|VM_GROWSUP */ - if (file) { - if (vm_flags & (VM_GROWSDOWN|VM_GROWSUP)) - goto free_vma; if (vm_flags & VM_DENYWRITE) { error = deny_write_access(file); if (error) @@ -1573,8 +1573,6 @@ munmap_back: pgoff = vma->vm_pgoff; vm_flags = vma->vm_flags; } else if (vm_flags & VM_SHARED) { - if (unlikely(vm_flags & (VM_GROWSDOWN|VM_GROWSUP))) - goto free_vma; error = shmem_zero_setup(vma); if (error) goto free_vma; _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are origin.patch anon_inodefs-forbid-open-via-proc.patch autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch signals-eventpoll-set-saved_sigmask-at-the-start.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html