The patch titled Subject: mm: iov_iter: have iov_iter_advance() decrement nr_segs appropriately has been removed from the -mm tree. Its filename was iov_iter-have-iov_iter_advance-decrement-nr_segs-appropriately.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ From: Jeff Layton <jlayton@xxxxxxxxxx> Subject: mm: iov_iter: have iov_iter_advance() decrement nr_segs appropriately Currently, when you call iov_iter_advance, then the pointer to the iovec array can be incremented, but it does not decrement the nr_segs value in the iov_iter struct. The result is a iov_iter struct with a nr_segs value that goes beyond the end of the array. While I'm not aware of anything that's specifically broken by this, it seems odd and a bit dangerous not to decrement that value. If someone were to trust the nr_segs value to be correct, then they could end up walking off the end of the array. Changing this might also provide some micro-optimization when dealing with the last iovec in an array. Many of the other routines that deal with iov_iter have optimized codepaths when nr_segs == 1. Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> Cc: Nick Piggin <npiggin@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/filemap.c | 3 +++ 1 file changed, 3 insertions(+) diff -puN mm/filemap.c~iov_iter-have-iov_iter_advance-decrement-nr_segs-appropriately mm/filemap.c --- a/mm/filemap.c~iov_iter-have-iov_iter_advance-decrement-nr_segs-appropriately +++ a/mm/filemap.c @@ -2115,6 +2115,7 @@ void iov_iter_advance(struct iov_iter *i } else { const struct iovec *iov = i->iov; size_t base = i->iov_offset; + unsigned long nr_segs = i->nr_segs; /* * The !iov->iov_len check ensures we skip over unlikely @@ -2130,11 +2131,13 @@ void iov_iter_advance(struct iov_iter *i base += copy; if (iov->iov_len == base) { iov++; + nr_segs--; base = 0; } } i->iov = iov; i->iov_offset = base; + i->nr_segs = nr_segs; } } EXPORT_SYMBOL(iov_iter_advance); _ Patches currently in -mm which might be from jlayton@xxxxxxxxxx are origin.patch linux-next.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