diff options
| author |   Richard Cheng <icheng@nvidia.com> | 2026-06-26 18:41:02 +0800 |
|---|---|---|
| committer |   Dave Jiang <dave.jiang@intel.com> | 2026-07-14 13:41:03 -0700 |
| commit | 2aeb21fe557ef154f0cdf4f9745ebd8d5b31ca83 (patch) | |
| tree | 0a13ceb85d1eb32d828c3b4d2787d13cbc886abe | |
| parent | cxl/features: Reject Set Features output buffer smaller than the header (diff) | |
cxl/features: Clamp Get Feature output size to the remaining buffer
cxl_get_feature() reads a feature in a loop but passes a fixed size_out
as the output capacity every iteration. On the last partial iteration
the buffer has less room left, so a device that returns more than asked
can overflow feat_out.
Use the per-iter size data_to_rd_size, which already tracks the
remaining room, as the output capacity.
Fixes: 5e5ac21f629d ("cxl/mbox: Add GET_FEATURE mailbox command")
Signed-off-by: Richard Cheng <icheng@nvidia.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Link: https://patch.msgid.link/20260626104102.53892-4-icheng@nvidia.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
| -rw-r--r-- | drivers/cxl/core/features.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/cxl/core/features.c b/drivers/cxl/core/features.c index 2eedabb5f702..ba6d2a5acb74 100644 --- a/drivers/cxl/core/features.c +++ b/drivers/cxl/core/features.c @@ -225,7 +225,7 @@ size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid, void *feat_out, size_t feat_out_size, u16 offset, u16 *return_code) { - size_t data_to_rd_size, size_out; + size_t data_to_rd_size; struct cxl_mbox_get_feat_in pi; struct cxl_mbox_cmd mbox_cmd; size_t data_rcvd_size = 0; @@ -237,7 +237,6 @@ size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid, if (!feat_out || !feat_out_size) return 0; - size_out = min(feat_out_size, cxl_mbox->payload_size); uuid_copy(&pi.uuid, feat_uuid); pi.selection = selection; @@ -252,7 +251,7 @@ size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid, .opcode = CXL_MBOX_OP_GET_FEATURE, .size_in = sizeof(pi), .payload_in = &pi, - .size_out = size_out, + .size_out = data_to_rd_size, .payload_out = feat_out + data_rcvd_size, .min_out = data_to_rd_size, }; |