6.17-stable review patch. If anyone has any objections, please let me know.
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From: Dave Jiang dave.jiang@intel.com
[ Upstream commit a375246fcf2bbdaeb1df7fa7ee5a8b884a89085e ]
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: <removed> [ 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 dave@stgolabs.net Reviewed-by: Alison Schofield alison.schofield@intel.com Signed-off-by: Dave Jiang dave.jiang@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/cxl/core/features.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/cxl/core/features.c b/drivers/cxl/core/features.c index 7c750599ea690..4bc484b46f439 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))