4.6-stable review patch. If anyone has any objections, please let me know.
------------------ From: Ville Viinikka <[email protected]> commit bfe5b1b1e013f7b1c0fd2ac3b3c8c380114b3fb9 upstream. Set 'idata->buf' to NULL so that it never gets returned without initialization. This fixes a bug where mmc_blk_ioctl_cmd() would free both 'idata' and 'idata->buf' but 'idata->buf' was returned uninitialized. Fixes: 1ff8950c0433 ("mmc: block: change to use kmalloc when copy data from userspace") Signed-off-by: Ville Viinikka <[email protected]> Signed-off-by: Ulf Hansson <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/mmc/card/block.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -352,8 +352,10 @@ static struct mmc_blk_ioc_data *mmc_blk_ goto idata_err; } - if (!idata->buf_bytes) + if (!idata->buf_bytes) { + idata->buf = NULL; return idata; + } idata->buf = kmalloc(idata->buf_bytes, GFP_KERNEL); if (!idata->buf) {
