4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx> commit 96a3aefb8ffde23180130460b0b2407b328eb727 upstream. In xfs_dir3_data_read, we can encounter the situation where err == 0 and *bpp == NULL if the given bno offset happens to be a hole; this leads to a crash if we try to set the buffer type after the _da_read_buf call. Holes can happen due to corrupt or malicious entries in the bmbt data, so be a little more careful when we're handling buffers. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx> Signed-off-by: Dave Chinner <david@xxxxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/xfs/libxfs/xfs_dir2_data.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/xfs/libxfs/xfs_dir2_data.c +++ b/fs/xfs/libxfs/xfs_dir2_data.c @@ -329,7 +329,7 @@ xfs_dir3_data_read( err = xfs_da_read_buf(tp, dp, bno, mapped_bno, bpp, XFS_DATA_FORK, &xfs_dir3_data_buf_ops); - if (!err && tp) + if (!err && tp && *bpp) xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF); return err; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html