From: Dave Jiang Date: Thu, 9 Oct 2025 15:40:01 +0000 (-0700) Subject: cxl/features: Add check for no entries in cxl_feature_info X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a375246fcf2bbdaeb1df7fa7ee5a8b884a89085e;p=users%2Fhch%2Fmisc.git cxl/features: Add check for no entries in cxl_feature_info cxl EDAC calls cxl_feature_info() to get the feature information and if the hardware has no Features support, cxlfs may be passed in as NULL. [ 51.957498] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 51.965571] #PF: supervisor read access in kernel mode [ 51.971559] #PF: error_code(0x0000) - not-present page [ 51.977542] PGD 17e4f6067 P4D 0 [ 51.981384] Oops: Oops: 0000 [#1] SMP NOPTI [ 51.986300] CPU: 49 UID: 0 PID: 3782 Comm: systemd-udevd Not tainted 6.17.0dj test+ #64 PREEMPT(voluntary) [ 51.997355] Hardware name: [ 52.009790] RIP: 0010:cxl_feature_info+0xa/0x80 [cxl_core] Add a check for cxlfs before dereferencing it and return -EOPNOTSUPP if there is no cxlfs created due to no hardware support. Fixes: eb5dfcb9e36d ("cxl: Add support to handle user feature commands for set feature") Reviewed-by: Davidlohr Bueso Reviewed-by: Alison Schofield Signed-off-by: Dave Jiang --- diff --git a/drivers/cxl/core/features.c b/drivers/cxl/core/features.c index 7c750599ea69..4bc484b46f43 100644 --- a/drivers/cxl/core/features.c +++ b/drivers/cxl/core/features.c @@ -371,6 +371,9 @@ cxl_feature_info(struct cxl_features_state *cxlfs, { struct cxl_feat_entry *feat; + if (!cxlfs || !cxlfs->entries) + return ERR_PTR(-EOPNOTSUPP); + for (int i = 0; i < cxlfs->entries->num_features; i++) { feat = &cxlfs->entries->ent[i]; if (uuid_equal(uuid, &feat->uuid))