diff options
| author | Viresh Kumar <viresh.kumar@linaro.org> | 2019-11-07 08:50:25 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-12-17 20:38:56 +0100 |
| commit | 589d00cebfc204c579c3212dd3c00a03c298d298 (patch) | |
| tree | 53b64e12b42765eb6162bd96d9d48540aedc35c7 | |
| parent | d83013e02e15826658e25857795270e12e290529 (diff) | |
RDMA/qib: Validate ->show()/store() callbacks before calling them
commit 7ee23491b39259ae83899dd93b2a29ef0f22f0a7 upstream.
The permissions of the read-only or write-only sysfs files can be
changed (as root) and the user can then try to read a write-only file or
write to a read-only file which will lead to kernel crash here.
Protect against that by always validating the show/store callbacks.
Link: https://lore.kernel.org/r/d45cc26361a174ae12dbb86c994ef334d257924b.1573096807.git.viresh.kumar@linaro.org
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/infiniband/hw/qib/qib_sysfs.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/qib/qib_sysfs.c b/drivers/infiniband/hw/qib/qib_sysfs.c index ca2638d8f35e..d831f3e61ae8 100644 --- a/drivers/infiniband/hw/qib/qib_sysfs.c +++ b/drivers/infiniband/hw/qib/qib_sysfs.c @@ -301,6 +301,9 @@ static ssize_t qib_portattr_show(struct kobject *kobj, struct qib_pportdata *ppd = container_of(kobj, struct qib_pportdata, pport_kobj); + if (!pattr->show) + return -EIO; + return pattr->show(ppd, buf); } @@ -312,6 +315,9 @@ static ssize_t qib_portattr_store(struct kobject *kobj, struct qib_pportdata *ppd = container_of(kobj, struct qib_pportdata, pport_kobj); + if (!pattr->store) + return -EIO; + return pattr->store(ppd, buf, len); } |