4.20-stable review patch. If anyone has any objections, please let me know.
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From: Gustavo A. R. Silva gustavo@embeddedor.com
commit e25df7812c91f62581301f9a7ac102acf92e4937 upstream.
There is a potential NULL pointer dereference in case kzalloc() fails and returns NULL.
Fix this by adding a NULL check on *session*
Also, update the function header with information about the expected return on failure and remove unnecessary variable rc.
This issue was detected with the help of Coccinelle.
Fixes: 0eca353e7ae7 ("misc: IBM Virtual Management Channel Driver (VMC)") Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva gustavo@embeddedor.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/misc/ibmvmc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
--- a/drivers/misc/ibmvmc.c +++ b/drivers/misc/ibmvmc.c @@ -820,21 +820,24 @@ static int ibmvmc_send_msg(struct crq_se * * Return: * 0 - Success + * Non-zero - Failure */ static int ibmvmc_open(struct inode *inode, struct file *file) { struct ibmvmc_file_session *session; - int rc = 0;
pr_debug("%s: inode = 0x%lx, file = 0x%lx, state = 0x%x\n", __func__, (unsigned long)inode, (unsigned long)file, ibmvmc.state);
session = kzalloc(sizeof(*session), GFP_KERNEL); + if (!session) + return -ENOMEM; + session->file = file; file->private_data = session;
- return rc; + return 0; }
/**