From: Dave Gerlach Date: Wed, 25 May 2016 20:41:28 +0000 (-0500) Subject: remoteproc: Fix potential race condition in rproc_add X-Git-Tag: v4.7.2~115 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=53a234d9cbbbbbd7b25097c6f521c889473b56a8;p=thirdparty%2Fkernel%2Fstable.git remoteproc: Fix potential race condition in rproc_add commit d2e12e66a939c54ed84e5f1b6947f0c45f6c56eb upstream. rproc_add adds the newly created remoteproc to a list for use by rproc_get_by_phandle and then does some additional processing to finish adding the remoteproc. This leaves a small window of time in which the rproc is available in the list but not yet fully initialized, so if another driver comes along and gets a handle to the rproc, it will be invalid. Rearrange the code in rproc_add to make sure the rproc is added to the list only after it has been successfuly initialized. Fixes: fec47d863587 ("remoteproc: introduce rproc_get_by_phandle API") Signed-off-by: Dave Gerlach Signed-off-by: Bjorn Andersson Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index db3958b3f0945..fe0539ed9cb59 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -1264,11 +1264,6 @@ int rproc_add(struct rproc *rproc) if (ret < 0) return ret; - /* expose to rproc_get_by_phandle users */ - mutex_lock(&rproc_list_mutex); - list_add(&rproc->node, &rproc_list); - mutex_unlock(&rproc_list_mutex); - dev_info(dev, "%s is available\n", rproc->name); dev_info(dev, "Note: remoteproc is still under development and considered experimental.\n"); @@ -1276,8 +1271,16 @@ int rproc_add(struct rproc *rproc) /* create debugfs entries */ rproc_create_debug_dir(rproc); + ret = rproc_add_virtio_devices(rproc); + if (ret < 0) + return ret; - return rproc_add_virtio_devices(rproc); + /* expose to rproc_get_by_phandle users */ + mutex_lock(&rproc_list_mutex); + list_add(&rproc->node, &rproc_list); + mutex_unlock(&rproc_list_mutex); + + return 0; } EXPORT_SYMBOL(rproc_add);