kernel/linux.git/fs/splice.c, branch v5.10.258

splice: don't generate zero-len segement bvecs

2024-11-17T13:59:37+00:00

commit 0f1d344feb534555a0dcd0beafb7211a37c5355e upstream. iter_file_splice_write() may spawn bvec segments with zero-length. In preparation for prohibiting them, filter out by hand at splice level. Reviewed-by: Christoph Hellwig Signed-off-by: Pavel Begunkov Reviewed-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman

Revert "fs: check FMODE_LSEEK to control internal pipe splicing"

2022-10-17T15:26:07+00:00

This reverts commit fd0a6e99b61e6c08fa5cf585d54fd956f70c73a6. Which was upstream commit 97ef77c52b789ec1411d360ed99dca1efe4b2c81. The commit is missing dependencies and breaks NFS tests, remove it for now. Reported-by: Saeed Mirzamohammadi Signed-off-by: Sasha Levin

fs: check FMODE_LSEEK to control internal pipe splicing

2022-08-21T13:15:47+00:00

[ Upstream commit 97ef77c52b789ec1411d360ed99dca1efe4b2c81 ] The original direct splicing mechanism from Jens required the input to be a regular file because it was avoiding the special socket case. It also recognized blkdevs as being close enough to a regular file. But it forgot about chardevs, which behave the same way and work fine here. This is an okayish heuristic, but it doesn't totally work. For example, a few chardevs should be spliceable here. And a few regular files shouldn't. This patch fixes this by instead checking whether FMODE_LSEEK is set, which represents decently enough what we need rewinding for when splicing to internal pipes. Fixes: b92ce5589374 ("[PATCH] splice: add direct fd <-> fd splicing support") Cc: Jens Axboe Signed-off-by: Jason A. Donenfeld Signed-off-by: Al Viro Signed-off-by: Sasha Levin

Merge tag 'io_uring-5.10-2020-10-24' of git://git.kernel.dk/linux-block

2020-10-24T19:40:18+00:00

Pull io_uring fixes from Jens Axboe: - fsize was missed in previous unification of work flags - Few fixes cleaning up the flags unification creds cases (Pavel) - Fix NUMA affinities for completely unplugged/replugged node for io-wq - Two fallout fixes from the set_fs changes. One local to io_uring, one for the splice entry point that io_uring uses. - Linked timeout fixes (Pavel) - Removal of ->flush() ->files work-around that we don't need anymore with referenced files (Pavel) - Various cleanups (Pavel) * tag 'io_uring-5.10-2020-10-24' of git://git.kernel.dk/linux-block: splice: change exported internal do_splice() helper to take kernel offset io_uring: make loop_rw_iter() use original user supplied pointers io_uring: remove req cancel in ->flush() io-wq: re-set NUMA node affinities if CPUs come online io_uring: don't reuse linked_timeout io_uring: unify fsize with def->work_flags io_uring: fix racy REQ_F_LINK_TIMEOUT clearing io_uring: do poll's hash_node init in common code io_uring: inline io_poll_task_handler() io_uring: remove extra ->file check in poll prep io_uring: make cached_cq_overflow non atomic_t io_uring: inline io_fail_links() io_uring: kill ref get/drop in personality init io_uring: flags-based creds init in queue

splice: change exported internal do_splice() helper to take kernel offset

2020-10-22T20:15:51+00:00

With the set_fs change, we can no longer rely on copy_{to,from}_user() accepting a kernel pointer, and it was bad form to do so anyway. Clean this up and change the internal helper that io_uring uses to deal with kernel pointers instead. This puts the offset copy in/out in __do_splice() instead, which just calls the same helper. Signed-off-by: Jens Axboe

Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2020-10-22T16:59:21+00:00

Pull initial set_fs() removal from Al Viro: "Christoph's set_fs base series + fixups" * 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Allow a NULL pos pointer to __kernel_read fs: Allow a NULL pos pointer to __kernel_write powerpc: remove address space overrides using set_fs() powerpc: use non-set_fs based maccess routines x86: remove address space overrides using set_fs() x86: make TASK_SIZE_MAX usable from assembly code x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h lkdtm: remove set_fs-based tests test_bitmap: remove user bitmap tests uaccess: add infrastructure for kernel builds with set_fs() fs: don't allow splice read/write without explicit ops fs: don't allow kernel reads and writes without iter ops sysctl: Convert to iter interfaces proc: add a read_iter method to proc proc_ops proc: cleanup the compat vs no compat file ops proc: remove a level of indentation in proc_get_inode

Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2020-10-12T23:35:51+00:00

Pull compat iovec cleanups from Al Viro: "Christoph's series around import_iovec() and compat variant thereof" * 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: security/keys: remove compat_keyctl_instantiate_key_iov mm: remove compat_process_vm_{readv,writev} fs: remove compat_sys_vmsplice fs: remove the compat readv/writev syscalls fs: remove various compat readv/writev helpers iov_iter: transparently handle compat iovecs in import_iovec iov_iter: refactor rw_copy_check_uvector and import_iovec iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c compat.h: fix a spelling error in

splice: teach splice pipe reading about empty pipe buffers

2020-10-06T17:27:22+00:00

Tetsuo Handa reports that splice() can return 0 before the real EOF, if the data in the splice source pipe is an empty pipe buffer. That empty pipe buffer case doesn't happen in any normal situation, but you can trigger it by doing a write to a pipe that fails due to a page fault. Tetsuo has a test-case to show the behavior: #define _GNU_SOURCE #include #include #include #include int main(int argc, char *argv[]) { const int fd = open("/tmp/testfile", O_WRONLY | O_CREAT, 0600); int pipe_fd[2] = { -1, -1 }; pipe(pipe_fd); write(pipe_fd[1], NULL, 4096); /* This splice() should wait unless interrupted. */ return !splice(pipe_fd[0], NULL, fd, NULL, 65536, 0); } which results in write(5, NULL, 4096) = -1 EFAULT (Bad address) splice(4, NULL, 3, NULL, 65536, 0) = 0 and this can confuse splice() users into believing they have hit EOF prematurely. The issue was introduced when the pipe write code started pre-allocating the pipe buffers before copying data from user space. This is modified verion of Tetsuo's original patch. Fixes: a194dfe6e6f6 ("pipe: Rearrange sequence in pipe_write() to preallocate slot") Link:https://lore.kernel.org/linux-fsdevel/20201005121339.4063-1-penguin-kernel@I-love.SAKURA.ne.jp/ Reported-by: Tetsuo Handa Acked-by: Tetsuo Handa Signed-off-by: Linus Torvalds

fs: remove compat_sys_vmsplice

2020-10-03T04:02:15+00:00

Now that import_iovec handles compat iovecs, the native vmsplice syscall can be used for the compat case as well. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro

iov_iter: transparently handle compat iovecs in import_iovec

2020-10-03T04:02:13+00:00

Use in compat_syscall to import either native or the compat iovecs, and remove the now superflous compat_import_iovec. This removes the need for special compat logic in most callers, and the remaining ones can still be simplified by using __import_iovec with a bool compat parameter. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro