diff options
| author | Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> | 2009-05-14 19:38:24 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-05-15 08:03:23 -0700 |
| commit | 1f71ebedb3f8ce9108978168759c8551d873a912 (patch) | |
| tree | 604f633fa092872f8b70873780c36e024de3677a /fs/devpts | |
| parent | bd67ce0f661482bd073f94144dd7e5a093ef012f (diff) | |
| download | linux-1f71ebedb3f8ce9108978168759c8551d873a912.tar.bz2 | |
devpts: correctly set default options
devpts_get_sb() calls memset(0) to clear mount options and calls
parse_mount_options() if user specified any mount options.
The memset(0) is bogus since the 'mode' and 'ptmxmode' options are
non-zero by default. parse_mount_options() restores options to default
anyway and can properly deal with NULL mount options.
So in devpts_get_sb() remove memset(0) and call parse_mount_options() even
for NULL mount options.
Bug reported by Eric Paris: http://lkml.org/lkml/2009/5/7/448.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Reported-by: Eric Paris <eparis@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Reviewed-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/devpts')
| -rw-r--r-- | fs/devpts/inode.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c index 21165cf934ff..c68edb969441 100644 --- a/fs/devpts/inode.c +++ b/fs/devpts/inode.c @@ -90,6 +90,15 @@ static inline struct super_block *pts_sb_from_inode(struct inode *inode) #define PARSE_MOUNT 0 #define PARSE_REMOUNT 1 +/* + * parse_mount_options(): + * Set @opts to mount options specified in @data. If an option is not + * specified in @data, set it to its default value. The exception is + * 'newinstance' option which can only be set/cleared on a mount (i.e. + * cannot be changed during remount). + * + * Note: @data may be NULL (in which case all options are set to default). + */ static int parse_mount_options(char *data, int op, struct pts_mount_opts *opts) { char *p; @@ -355,12 +364,9 @@ static int devpts_get_sb(struct file_system_type *fs_type, struct pts_mount_opts opts; struct super_block *s; - memset(&opts, 0, sizeof(opts)); - if (data) { - error = parse_mount_options(data, PARSE_MOUNT, &opts); - if (error) - return error; - } + error = parse_mount_options(data, PARSE_MOUNT, &opts); + if (error) + return error; if (opts.newinstance) s = sget(fs_type, NULL, set_anon_super, NULL); |