On Mon, Jan 26, 2009 at 5:59 PM, Jan Kara <jack@xxxxxxx> wrote: >> On Tue, Jan 20, 2009 at 10:36 PM, Manish Katiyar <mkatiyar@xxxxxxxxx> wrote: >> > ext2_quota_read doesn't bzeroes tmp_bh before calling ext2_get_block() >> > where we access the b_size of it. Since it is a local variable it >> > might contain some garbage. Make sure it is filled with zero before >> > passing. >> >> Hi Ted/mingming, >> >> Any feedback on this ?? > Ops, sorry. I wanted to reply but first I wanted to research more > whether we can set b_size to 0 and then forgot about it. Looking into > other code (e.g. in fs/mpage.c or fs/buffer.c) I think it would be > better to set b_size to sb->s_blocksize and be done with that. Mapping > code does not need anything else set to a deterministic value so using > memset is a bit overkill. Thanks Jan for your comments. Yes memset is an overkill. I did it just because other users of ext2_get_block were doing the same way. Will rework the patch with setting b_size as blocksize and send again. Thanks - Manish > > Honza > >> > Signed-off-by : Manish Katiyar <mkatiyar@xxxxxxxxx> >> > --- >> > fs/ext2/super.c | 4 ++-- >> > 1 files changed, 2 insertions(+), 2 deletions(-) >> > >> > diff --git a/fs/ext2/super.c b/fs/ext2/super.c >> > index da8bdea..d10aa44 100644 >> > --- a/fs/ext2/super.c >> > +++ b/fs/ext2/super.c >> > @@ -1327,7 +1327,7 @@ static ssize_t ext2_quota_read(struct >> > super_block *sb, int type, char *data, >> > tocopy = sb->s_blocksize - offset < toread ? >> > sb->s_blocksize - offset : toread; >> > >> > - tmp_bh.b_state = 0; >> > + memset(&tmp_bh, 0, sizeof(struct buffer_head)); >> > err = ext2_get_block(inode, blk, &tmp_bh, 0); >> > if (err < 0) >> > return err; >> > @@ -1366,7 +1366,7 @@ static ssize_t ext2_quota_write(struct >> > super_block *sb, int type, >> > tocopy = sb->s_blocksize - offset < towrite ? >> > sb->s_blocksize - offset : towrite; >> > >> > - tmp_bh.b_state = 0; >> > + memset(&tmp_bh, 0, sizeof(struct buffer_head)); >> > err = ext2_get_block(inode, blk, &tmp_bh, 1); >> > if (err < 0) >> > goto out; >> > -- >> > 1.5.4.3 >> > >> > >> > Thanks - >> > Manish >> > >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > Jan Kara <jack@xxxxxxx> > SuSE CR Labs > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
