diff options
| author | Ma Ke <make24@iscas.ac.cn> | 2025-07-17 10:23:07 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-01 09:48:43 +0100 |
| commit | cf8e62f6e1b25075e08e88aa8a187f1c28ab79c4 (patch) | |
| tree | f013197c51cc97921696cd332efcf1625750b5d6 | |
| parent | 5b8d6cb9a03dd8ef6418b29bf95f3779cb5ed4b2 (diff) | |
bus: fsl-mc: Fix potential double device reference in fsl_mc_get_endpoint()
commit bddbe13d36a02d5097b99cf02354d5752ad1ac60 upstream.
The fsl_mc_get_endpoint() function may call fsl_mc_device_lookup()
twice, which would increment the device's reference count twice if
both lookups find a device. This could lead to a reference count leak.
Found by code review.
Cc: stable@vger.kernel.org
Fixes: 1ac210d128ef ("bus: fsl-mc: add the fsl_mc_get_endpoint function")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Fixes: 8567494cebe5 ("bus: fsl-mc: rescan devices if endpoint not found")
Link: https://patch.msgid.link/20250717022309.3339976-1-make24@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/bus/fsl-mc/fsl-mc-bus.c | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c index 58d16ff166c2..4575d9a4e5ed 100644 --- a/drivers/bus/fsl-mc/fsl-mc-bus.c +++ b/drivers/bus/fsl-mc/fsl-mc-bus.c @@ -942,6 +942,7 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev, struct fsl_mc_obj_desc endpoint_desc = {{ 0 }}; struct dprc_endpoint endpoint1 = {{ 0 }}; struct dprc_endpoint endpoint2 = {{ 0 }}; + struct fsl_mc_bus *mc_bus; int state, err; mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent); @@ -965,6 +966,8 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev, strcpy(endpoint_desc.type, endpoint2.type); endpoint_desc.id = endpoint2.id; endpoint = fsl_mc_device_lookup(&endpoint_desc, mc_bus_dev); + if (endpoint) + return endpoint; /* * We know that the device has an endpoint because we verified by @@ -972,17 +975,13 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev, * yet discovered by the fsl-mc bus, thus the lookup returned NULL. * Force a rescan of the devices in this container and retry the lookup. */ - if (!endpoint) { - struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev); - - if (mutex_trylock(&mc_bus->scan_mutex)) { - err = dprc_scan_objects(mc_bus_dev, true); - mutex_unlock(&mc_bus->scan_mutex); - } - - if (err < 0) - return ERR_PTR(err); + mc_bus = to_fsl_mc_bus(mc_bus_dev); + if (mutex_trylock(&mc_bus->scan_mutex)) { + err = dprc_scan_objects(mc_bus_dev, true); + mutex_unlock(&mc_bus->scan_mutex); } + if (err < 0) + return ERR_PTR(err); endpoint = fsl_mc_device_lookup(&endpoint_desc, mc_bus_dev); /* |