From: ebiederm@xmission.com (Eric W. Biederman)
To: Badari Pulavarty <pbadari@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>,
linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
Hugh Dickins <hugh@veritas.com>, Tejun Heo <tj@kernel.org>,
Alexey Dobriyan <adobriyan@gmail.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
Greg Kroah-Hartman <gregkh@suse.de>,
Nick Piggin <npiggin@suse.de>,
Andrew Morton <akpm@linux-foundation.org>,
Christoph Hellwig <hch@infradead.org>,
"Eric W. Biederman" <ebiederm@maxwell.arastra.com>,
"Eric W. Biederman" <ebiederm@aristanetworks.com>
Subject: Re: [PATCH 07/23] vfs: Teach sendfile,splice,tee,and vmsplice to use file_hotplug_lock
Date: Fri, 05 Jun 2009 12:37:25 -0700 [thread overview]
Message-ID: <m1y6s64glm.fsf@fess.ebiederm.org> (raw)
In-Reply-To: <1244072363.6383.15.camel@badari-desktop> (Badari Pulavarty's message of "Wed\, 03 Jun 2009 16\:39\:23 -0700")
Badari Pulavarty <pbadari@gmail.com> writes:
> On Mon, 2009-06-01 at 14:50 -0700, Eric W. Biederman wrote:
>> From: Eric W. Biederman <ebiederm@maxwell.arastra.com>
>>
>> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
>> ---
>> fs/read_write.c | 28 +++++++++----
>> fs/splice.c | 111 +++++++++++++++++++++++++++++++++++++-----------------
>> 2 files changed, 95 insertions(+), 44 deletions(-)
>>
>> diff --git a/fs/read_write.c b/fs/read_write.c
>> index 718baea..c473d74 100644
>> --- a/fs/read_write.c
>> +++ b/fs/read_write.c
>> @@ -861,21 +861,24 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
>> goto out;
>> if (!(in_file->f_mode & FMODE_READ))
>> goto fput_in;
>> + retval = -EIO;
>> + if (!file_hotplug_read_trylock(in_file))
>> + goto fput_in;
>> retval = -EINVAL;
>> in_inode = in_file->f_path.dentry->d_inode;
>> if (!in_inode)
>> - goto fput_in;
>> + goto unlock_in;
>> if (!in_file->f_op || !in_file->f_op->splice_read)
>> - goto fput_in;
>> + goto unlock_in;
>> retval = -ESPIPE;
>> if (!ppos)
>> ppos = &in_file->f_pos;
>> else
>> if (!(in_file->f_mode & FMODE_PREAD))
>> - goto fput_in;
>> + goto unlock_in;
>> retval = rw_verify_area(READ, in_file, ppos, count);
>> if (retval < 0)
>> - goto fput_in;
>> + goto unlock_in;
>> count = retval;
>>
>> /*
>> @@ -884,16 +887,19 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
>> retval = -EBADF;
>> out_file = fget_light(out_fd, &fput_needed_out);
>> if (!out_file)
>> - goto fput_in;
>> + goto unlock_in;
>> if (!(out_file->f_mode & FMODE_WRITE))
>> goto fput_out;
>> + retval = -EIO;
>> + if (!file_hotplug_read_trylock(out_file))
>> + goto fput_out;
>> retval = -EINVAL;
>> if (!out_file->f_op || !out_file->f_op->sendpage)
>> - goto fput_out;
>> + goto unlock_out;
>> out_inode = out_file->f_path.dentry->d_inode;
>> retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count);
>> if (retval < 0)
>> - goto fput_out;
>> + goto unlock_out;
>> count = retval;
>>
>> if (!max)
>> @@ -902,11 +908,11 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
>> pos = *ppos;
>> retval = -EINVAL;
>> if (unlikely(pos < 0))
>> - goto fput_out;
>> + goto unlock_out;
>> if (unlikely(pos + count > max)) {
>> retval = -EOVERFLOW;
>> if (pos >= max)
>> - goto fput_out;
>> + goto unlock_out;
>> count = max - pos;
>> }
>>
>> @@ -933,8 +939,12 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
>> if (*ppos > max)
>> retval = -EOVERFLOW;
>>
>> +unlock_out:
>> + file_hotplug_read_unlock(out_file);
>> fput_out:
>> fput_light(out_file, fput_needed_out);
>> +unlock_in:
>> + file_hotplug_read_unlock(in_file);
>> fput_in:
>> fput_light(in_file, fput_needed_in);
>> out:
>> diff --git a/fs/splice.c b/fs/splice.c
>> index 666953d..fc6b3a5 100644
>> --- a/fs/splice.c
>> +++ b/fs/splice.c
>> @@ -1464,15 +1464,21 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, iov,
>>
>> error = -EBADF;
>> file = fget_light(fd, &fput);
>> - if (file) {
>> - if (file->f_mode & FMODE_WRITE)
>> - error = vmsplice_to_pipe(file, iov, nr_segs, flags);
>> - else if (file->f_mode & FMODE_READ)
>> - error = vmsplice_to_user(file, iov, nr_segs, flags);
>> + if (!file)
>> + goto out;
>>
>> - fput_light(file, fput);
>> - }
>> + if (!file_hotplug_read_trylock(file))
>> + goto fput_file;
>>
>> + if (file->f_mode & FMODE_WRITE)
>> + error = vmsplice_to_pipe(file, iov, nr_segs, flags);
>> + else if (file->f_mode & FMODE_READ)
>> + error = vmsplice_to_user(file, iov, nr_segs, flags);
>> +
>> + file_hotplug_read_unlock(file);
>> +fput_file:
>> + fput_light(file, fput);
>> +out:
>> return error;
>> }
>>
>> @@ -1489,21 +1495,39 @@ SYSCALL_DEFINE6(splice, int, fd_in, loff_t __user *, off_in,
>>
>> error = -EBADF;
>> in = fget_light(fd_in, &fput_in);
>> - if (in) {
>> - if (in->f_mode & FMODE_READ) {
>> - out = fget_light(fd_out, &fput_out);
>> - if (out) {
>> - if (out->f_mode & FMODE_WRITE)
>> - error = do_splice(in, off_in,
>> - out, off_out,
>> - len, flags);
>> - fput_light(out, fput_out);
>> - }
>> - }
>> + if (!in)
>> + goto out;
>>
>> - fput_light(in, fput_in);
>> - }
>> + if (!(in->f_mode & FMODE_READ))
>> + goto fput_in;
>> +
>> + error = -EIO;
>> + if (!file_hotplug_read_trylock(in))
>> + goto fput_in;
>> +
>> + error = -EBADF;
>> + out = fget_light(fd_out, &fput_out);
>> + if (!out)
>> + goto unlock_in;
>> +
>> + if (!(out->f_mode & FMODE_WRITE))
>> + goto fput_out;
>> +
>> + error = -EIO;
>> + if (!file_hotplug_read_trylock(out))
>> + goto fput_out;
>> +
>> + error = do_splice(in, off_in, out, off_out, len, flags);
>>
>> + file_hotplug_read_unlock(out);
>> +fput_out:
>> + fput_light(out, fput_out);
>> +unlock_in:
>> + file_hotplug_read_unlock(in);
>> +fput_in:
>> + fput_light(in, fput_in);
>> +
>> +out:
>> return error;
>> }
>>
>> @@ -1703,27 +1727,44 @@ static long do_tee(struct file *in, struct file *out, size_t len,
>>
>> SYSCALL_DEFINE4(tee, int, fdin, int, fdout, size_t, len, unsigned int, flags)
>> {
>> - struct file *in;
>> - int error, fput_in;
>> + struct file *in, *out;
>> + int error, fput_in, fput_out;
>>
>> if (unlikely(!len))
>> return 0;
>>
>> error = -EBADF;
>> in = fget_light(fdin, &fput_in);
>> - if (in) {
>> - if (in->f_mode & FMODE_READ) {
>> - int fput_out;
>> - struct file *out = fget_light(fdout, &fput_out);
>> -
>> - if (out) {
>> - if (out->f_mode & FMODE_WRITE)
>> - error = do_tee(in, out, len, flags);
>> - fput_light(out, fput_out);
>> - }
>> - }
>> - fput_light(in, fput_in);
>> - }
>> + if (!in)
>> + goto out;
>> +
>> + if (!(in->f_mode & FMODE_READ))
>> + goto unlock_in; <<<<<<<
>
> Shouldn't this be
> goto fput_in;
Good point. That is a bug.
> ? btw, its confusing to have labels and variables with same name:
> fput_in and fput_out. You may want to rename labels ?
Mayhap. I didn't start that one, although I am clearly spreading
it around here. Do you have a better naming suggestion?
>> + error = -EIO;
>> + if (!file_hotplug_read_trylock(in))
>> + goto fput_in;
>> +
>> + error = -EBADF;
>> + out = fget_light(fdout, &fput_out);
>> + if (!out)
>> + goto unlock_in;
>> +
>> + if (!(out->f_mode & FMODE_WRITE))
>> + goto fput_out;
>> +
>> + if (!file_hotplug_read_trylock(out))
>> + goto fput_out;
>> +
>> + error = do_tee(in, out, len, flags);
>> +
>> + file_hotplug_read_unlock(out);
>> +fput_out:
>> + fput_light(out, fput_out);
>> +unlock_in:
>> + file_hotplug_read_unlock(in);
>> +fput_in:
>> + fput_light(in, fput_in);
>> +out:
>> return error;
>> }
Eric
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next prev parent reply other threads:[~2009-06-05 19:37 UTC|newest]
Thread overview: 99+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-04-11 12:01 [RFC][PATCH 0/9] File descriptor hot-unplug support Eric W. Biederman
2009-04-11 12:03 ` [RFC][PATCH 1/9] mm: Introduce remap_file_mappings Eric W. Biederman
2009-04-11 12:05 ` [RFC][PATCH 2/9] mm: Implement generic support for revoking a mapping Eric W. Biederman
2009-04-11 12:06 ` [RFC][PATCH 3/9] sysfs: Use remap_file_mappings Eric W. Biederman
2009-04-11 12:07 ` [RFC][PATCH 4/9] vfs: Generalize the file_list Eric W. Biederman
2009-04-11 12:08 ` [RFC][PATCH 5/9] vfs: Introduce basic infrastructure for revoking a file Eric W. Biederman
2009-04-14 22:12 ` Jonathan Corbet
2009-04-15 2:55 ` Eric W. Biederman
2009-04-11 12:10 ` [RFC][PATCH 6/9] vfs: Utilize fops_read_lock where appropriate Eric W. Biederman
2009-04-11 12:11 ` [RFC][PATCH 7/9] vfs: Optimize fops_read_lock Eric W. Biederman
2009-04-11 12:13 ` [RFC][PATCH 8/9] vfs: Implement generic revoked file operations Eric W. Biederman
2009-04-12 18:56 ` Jamie Lokier
2009-04-12 20:04 ` Eric W. Biederman
2009-04-12 20:31 ` Jamie Lokier
2009-04-12 21:53 ` Eric W. Biederman
2009-04-12 20:54 ` Eric W. Biederman
2009-04-12 21:02 ` Jamie Lokier
2009-04-12 23:06 ` Eric W. Biederman
2009-04-11 12:14 ` [RFC][PATCH 9/9] proc: Use the generic vfs revoke facility that now exists Eric W. Biederman
2009-04-11 15:58 ` [RFC][PATCH 0/9] File descriptor hot-unplug support Al Viro
2009-04-11 16:49 ` Eric W. Biederman
2009-04-11 16:56 ` Al Viro
2009-04-11 23:57 ` Eric W. Biederman
2009-04-12 20:21 ` Eric W. Biederman
2009-04-14 3:16 ` Tejun Heo
2009-04-14 7:39 ` Eric W. Biederman
2009-04-14 7:45 ` Tejun Heo
2009-04-14 8:27 ` Eric W. Biederman
2009-04-14 8:49 ` Tejun Heo
2009-04-14 15:07 ` Jamie Lokier
2009-04-14 19:09 ` Eric W. Biederman
2009-06-01 21:45 ` [PATCH 0/23] File descriptor hot-unplug support v2 Eric W. Biederman
2009-06-01 21:50 ` [PATCH 01/23] mm: Introduce revoke_file_mappings Eric W. Biederman
2009-06-01 22:25 ` Andrew Morton
2009-06-02 0:12 ` Eric W. Biederman
2009-06-01 21:50 ` [PATCH 02/23] vfs: Implement unpoll_file Eric W. Biederman
2009-06-06 8:08 ` Al Viro
2009-06-01 21:50 ` [PATCH 03/23] vfs: Generalize the file_list Eric W. Biederman
2009-06-02 7:06 ` Nick Piggin
2009-06-05 19:33 ` Eric W. Biederman
2009-06-09 10:38 ` Nick Piggin
2009-06-09 18:38 ` Eric W. Biederman
2009-06-10 6:05 ` Nick Piggin
2009-06-01 21:50 ` [PATCH 04/23] vfs: Introduce infrastructure for revoking a file Eric W. Biederman
2009-06-02 5:16 ` Pekka Enberg
2009-06-02 6:51 ` Eric W. Biederman
2009-06-02 7:08 ` Pekka Enberg
2009-06-02 7:14 ` Nick Piggin
2009-06-02 17:06 ` Linus Torvalds
2009-06-02 20:52 ` Eric W. Biederman
2009-06-03 6:37 ` Nick Piggin
2009-06-02 22:56 ` Eric W. Biederman
2009-06-03 6:38 ` Nick Piggin
2009-06-05 9:03 ` Miklos Szeredi
2009-06-05 19:06 ` Eric W. Biederman
2009-06-01 21:50 ` [PATCH 05/23] vfs: Teach lseek to use file_hotplug_lock Eric W. Biederman
2009-06-01 21:50 ` [PATCH 06/23] vfs: Teach read/write to use file_hotplug_read_lock Eric W. Biederman
2009-06-01 21:50 ` [PATCH 07/23] vfs: Teach sendfile,splice,tee,and vmsplice to use file_hotplug_lock Eric W. Biederman
2009-06-03 23:39 ` Badari Pulavarty
2009-06-05 19:37 ` Eric W. Biederman [this message]
2009-06-01 21:50 ` [PATCH 08/23] vfs: Teach readdir " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 09/23] vfs: Teach poll and select " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 10/23] vfs: Teach do_path_lookup " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 11/23] mm: Teach mmap " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 12/23] vfs: Teach fcntl " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 13/23] vfs: Teach ioctl " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 14/23] vfs: Teach flock " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 15/23] vfs: Teach fallocate, and filp_close " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 16/23] vfs: Teach fstatfs, fstatfs64, ftruncate, fchdir, fchmod, fchown " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 17/23] proc: Teach /proc/<pid>/fd " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 18/23] vfs: Teach epoll " Eric W. Biederman
2009-06-02 16:51 ` Davide Libenzi
2009-06-02 21:23 ` Eric W. Biederman
2009-06-02 21:52 ` Davide Libenzi
2009-06-02 22:51 ` Eric W. Biederman
2009-06-03 14:57 ` Davide Libenzi
2009-06-03 20:53 ` Eric W. Biederman
2009-06-04 0:50 ` Davide Libenzi
2009-06-04 1:42 ` Eric W. Biederman
2009-06-01 21:50 ` [PATCH 19/23] eventpoll: Fix comment Eric W. Biederman
2009-06-01 21:50 ` [PATCH 20/23] vfs: Teach aio to use file_hotplug_lock Eric W. Biederman
2009-06-01 21:50 ` [PATCH 21/23] vfs: Teach fsync " Eric W. Biederman
2009-06-01 21:50 ` [PATCH 22/23] vfs: Teach fadvice to file_hotplug_lock Eric W. Biederman
2009-06-01 21:50 ` [PATCH 23/23] vfs: Teach readahead to use the file_hotplug_lock Eric W. Biederman
2009-06-03 23:25 ` Badari Pulavarty
2009-06-06 8:03 ` [PATCH 0/23] File descriptor hot-unplug support v2 Al Viro
2009-06-08 9:41 ` Miklos Szeredi
2009-06-08 10:24 ` Jamie Lokier
2009-06-08 16:29 ` Al Viro
2009-06-08 16:44 ` Miklos Szeredi
2009-06-08 17:50 ` Al Viro
2009-06-08 18:01 ` Linus Torvalds
2009-06-08 18:50 ` Al Viro
2009-06-08 19:18 ` Linus Torvalds
2009-06-09 6:42 ` Eric W. Biederman
2009-06-09 10:52 ` Nick Piggin
2009-06-09 5:50 ` Miklos Szeredi
2009-06-09 6:31 ` Eric W. Biederman
2009-06-09 6:22 ` Eric W. Biederman
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