The commit is pushed to "branch-rh7-3.10.0-229.7.2.vz7.8.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git after rh7-3.10.0-229.7.2.vz7.8.5 ------> commit 654ec46a26256b119505ba7dcc48e60c3c6a5cf5 Author: Maxim Patlasov <mpatla...@virtuozzo.com> Date: Mon Oct 12 14:19:03 2015 +0400
ms/fuse: break infinite loop in fuse_fill_write_pages() Backport bugfix from LKML. Original patch description: I got a report about unkillable task eating CPU. Thge further investigation shows, that the problem is in the fuse_fill_write_pages() function. If iov's first segment has zero length, we get an infinite loop, because we never reach iov_iter_advance() call. Fix this by calling iov_iter_advance() before repeating an attempt to copy data from userspace. A similar problem is described in 124d3b7041f ("fix writev regression: pan hanging unkillable and un-straceable"). Signed-off-by: Roman Gushchin <kl...@yandex-team.ru> Cc: Miklos Szeredi <mik...@szeredi.hu> Signed-off-by: Maxim Patlasov <mpatla...@virtuozzo.com> Acked-by: Dmitry Monakhov <dmonak...@virtuozzo.com> --- fs/fuse/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index a5c4125..88e6e46 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1327,6 +1327,7 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req, mark_page_accessed(page); + iov_iter_advance(ii, tmp); if (!tmp) { unlock_page(page); page_cache_release(page); @@ -1339,7 +1340,6 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req, req->page_descs[req->num_pages].length = tmp; req->num_pages++; - iov_iter_advance(ii, tmp); count += tmp; pos += tmp; offset += tmp; _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel