linux-toradex.git/fs/seq_file.c, branch v3.14.3

seq_file: always clear m->count when we free m->buf

2013-11-19T03:07:53+00:00

Once we'd freed m->buf, m->count should become zero - we have no valid
contents reachable via m->buf.

Reported-by: Charley (Hao Chuan) Chu 
Signed-off-by: Al Viro 
Signed-off-by: Linus Torvalds

seq_file: introduce seq_setwidth() and seq_pad()

2013-11-15T00:32:20+00:00

There are several users who want to know bytes written by seq_*() for
alignment purpose.  Currently they are using %n format for knowing it
because seq_*() returns 0 on success.

This patch introduces seq_setwidth() and seq_pad() for allowing them to
align without using %n format.

Signed-off-by: Tetsuo Handa 
Signed-off-by: Kees Cook 
Cc: Joe Perches 
Cc: David Miller 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

seq_file: always update file->f_pos in seq_lseek()

2013-10-25T14:46:40+00:00

This issue was first pointed out by Jiaxing Wang several months ago, but no
further comments:
https://lkml.org/lkml/2013/6/29/41

As we know pread() does not change f_pos, so after pread(), file->f_pos
and m->read_pos become different. And seq_lseek() does not update file->f_pos
if offset equals to m->read_pos, so after pread() and seq_lseek()(lseek to
m->read_pos), then a subsequent read may read from a wrong position, the
following program produces the problem:

    char str1[32] = { 0 };
    char str2[32] = { 0 };
    int poffset = 10;
    int count = 20;

    /*open any seq file*/
    int fd = open("/proc/modules", O_RDONLY);

    pread(fd, str1, count, poffset);
    printf("pread:%s\n", str1);

    /*seek to where m->read_pos is*/
    lseek(fd, poffset+count, SEEK_SET);

    /*supposed to read from poffset+count, but this read from position 0*/
    read(fd, str2, count);
    printf("read:%s\n", str2);

out put:
pread:
 ck_netbios_ns 12665
read:
 nf_conntrack_netbios

/proc/modules:
nf_conntrack_netbios_ns 12665 0 - Live 0xffffffffa038b000
nf_conntrack_broadcast 12589 1 nf_conntrack_netbios_ns, Live 0xffffffffa0386000

So we always update file->f_pos to offset in seq_lseek() to fix this issue.

Signed-off-by: Jiaxing Wang 
Signed-off-by: Gu Zheng 
Signed-off-by: Al Viro

seq_file: add seq_list_*_percpu helpers

2013-07-08T09:36:41+00:00

When we convert the file_lock_list to a set of percpu lists, we'll need
a way to iterate over them in order to output /proc/locks info. Add
some seq_list_*_percpu helpers to handle that.

Signed-off-by: Jeff Layton 
Acked-by: J. Bruce Fields 
Signed-off-by: Al Viro

new helper: single_open_size()

2013-04-09T18:13:29+00:00

Same as single_open(), but preallocates the buffer of given size.
Doesn't make any sense for sizes up to PAGE_SIZE and doesn't make
sense if output of show() exceeds PAGE_SIZE only rarely - seq_read()
will take care of growing the buffer and redoing show().  If you
_know_ that it will be large, it might make more sense to look into
saner iterator, rather than go with single-shot one.  If that's
impossible, single_open_size() might be for you.

Again, don't use that without a good reason; occasionally that's really
the best way to go, but very often there are better solutions.

Signed-off-by: Al Viro

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2013-03-03T21:23:03+00:00

Pull  more VFS bits from Al Viro:
 "Unfortunately, it looks like xattr series will have to wait until the
  next cycle ;-/

  This pile contains 9p cleanups and fixes (races in v9fs_fid_add()
  etc), fixup for nommu breakage in shmem.c, several cleanups and a bit
  more file_inode() work"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  constify path_get/path_put and fs_struct.c stuff
  fix nommu breakage in shmem.c
  cache the value of file_inode() in struct file
  9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry
  9p: make sure ->lookup() adds fid to the right dentry
  9p: untangle ->lookup() a bit
  9p: double iput() in ->lookup() if d_materialise_unique() fails
  9p: v9fs_fid_add() can't fail now
  v9fs: get rid of v9fs_dentry
  9p: turn fid->dlist into hlist
  9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine
  more file_inode() open-coded instances
  selinux: opened file can't have NULL or negative ->f_path.dentry

(In the meantime, the hlist traversal macros have changed, so this
required a semantic conflict fixup for the newly hlistified fid->dlist)

fs/seq_file.c:seq_lseek(): fix switch statement indenting

2013-02-28T03:10:12+00:00

[akpm@linux-foundation.org: checkpatch fixes]
Cc: Cyrill Gorcunov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

seq-file: use SEEK_ macros instead of hardcoded numbers

2013-02-28T03:10:12+00:00

Signed-off-by: Cyrill Gorcunov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

more file_inode() open-coded instances

2013-02-27T21:59:05+00:00

Signed-off-by: Al Viro

seq_file: fix new kernel-doc warnings

2013-01-10T22:35:24+00:00

Fix kernel-doc warnings in fs/seq_file.c:

  Warning(fs/seq_file.c:304): No description found for parameter 'whence'
  Warning(fs/seq_file.c:304): Excess function parameter 'origin' description in 'seq_lseek'

Signed-off-by: Randy Dunlap 
Cc: Alexander Viro 
Signed-off-by: Linus Torvalds