The patch titled Subject: radix-tree: fix oops after radix_tree_iter_retry has been added to the -mm tree. Its filename is radix-tree-fix-oops-after-radix_tree_iter_retry.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/radix-tree-fix-oops-after-radix_tree_iter_retry.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/radix-tree-fix-oops-after-radix_tree_iter_retry.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Konstantin Khlebnikov <koct9i@xxxxxxxxx> Subject: radix-tree: fix oops after radix_tree_iter_retry Helper radix_tree_iter_retry() resets next_index to the current index. In following radix_tree_next_slot current chunk size becomes zero. This isn't checked and it tries to dereference null pointer in slot. Tagged iterator is fine because retry happens only at slot 0 where tag bitmask in iter->tags is filled with single bit. Fixes: 46437f9a554f ("radix-tree: fix race in gang lookup") Signed-off-by: Konstantin Khlebnikov <koct9i@xxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Ohad Ben-Cohen <ohad@xxxxxxxxxx> Cc: Jeremiah Mahler <jmmahler@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/radix-tree.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff -puN include/linux/radix-tree.h~radix-tree-fix-oops-after-radix_tree_iter_retry include/linux/radix-tree.h --- a/include/linux/radix-tree.h~radix-tree-fix-oops-after-radix_tree_iter_retry +++ a/include/linux/radix-tree.h @@ -400,7 +400,7 @@ void **radix_tree_iter_retry(struct radi * @iter: pointer to radix tree iterator * Returns: current chunk size */ -static __always_inline unsigned +static __always_inline long radix_tree_chunk_size(struct radix_tree_iter *iter) { return iter->next_index - iter->index; @@ -434,9 +434,9 @@ radix_tree_next_slot(void **slot, struct return slot + offset + 1; } } else { - unsigned size = radix_tree_chunk_size(iter) - 1; + long size = radix_tree_chunk_size(iter); - while (size--) { + while (--size > 0) { slot++; iter->index++; if (likely(*slot)) _ Patches currently in -mm which might be from koct9i@xxxxxxxxx are mm-replace-vma_lock_anon_vma-with-anon_vma_lock_read-write.patch radix-tree-fix-oops-after-radix_tree_iter_retry.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html