| Message ID | 1349784762-28069-1-git-send-email-lczerner@redhat.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Tue, Oct 09, 2012 at 02:12:42PM +0200, Lukas Czerner wrote: > Currently if len argument in ext4_trim_fs() is smaller than one block, > the 'end' variable underflow. Avoid that by exiting right away if len > is smaller than one file system block. > > Signed-off-by: Lukas Czerner <lczerner@redhat.com> > --- > fs/ext4/mballoc.c | 7 ++++++- > 1 files changed, 6 insertions(+), 1 deletions(-) > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c > index f8b27bf..06c8526 100644 > --- a/fs/ext4/mballoc.c > +++ b/fs/ext4/mballoc.c > @@ -4989,13 +4989,18 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) > int ret = 0; > > start = range->start >> sb->s_blocksize_bits; > - end = start + (range->len >> sb->s_blocksize_bits) - 1; > minlen = EXT4_NUM_B2C(EXT4_SB(sb), > range->minlen >> sb->s_blocksize_bits); > > if (unlikely(minlen > EXT4_CLUSTERS_PER_GROUP(sb)) || > unlikely(start >= max_blks)) > return -EINVAL; > + > + end = range->len >> sb->s_blocksize_bits; > + if (0 == end) > + goto out; > + end += start - 1; > + > if (end >= max_blks) > end = max_blks - 1; > if (end <= first_data_blk) > -- > 1.7.7.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Looks good, Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index f8b27bf..06c8526 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4989,13 +4989,18 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) int ret = 0; start = range->start >> sb->s_blocksize_bits; - end = start + (range->len >> sb->s_blocksize_bits) - 1; minlen = EXT4_NUM_B2C(EXT4_SB(sb), range->minlen >> sb->s_blocksize_bits); if (unlikely(minlen > EXT4_CLUSTERS_PER_GROUP(sb)) || unlikely(start >= max_blks)) return -EINVAL; + + end = range->len >> sb->s_blocksize_bits; + if (0 == end) + goto out; + end += start - 1; + if (end >= max_blks) end = max_blks - 1; if (end <= first_data_blk)
Currently if len argument in ext4_trim_fs() is smaller than one block, the 'end' variable underflow. Avoid that by exiting right away if len is smaller than one file system block. Signed-off-by: Lukas Czerner <lczerner@redhat.com> --- fs/ext4/mballoc.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-)