From b9604bde694de3dbc35fe39ce851815fed449c21 Mon Sep 17 00:00:00 2001 From: Anders Roxell Date: Fri, 4 Jul 2025 08:31:32 +0200 Subject: [PATCH 1/3] pps: Fix IDR memory leak in module exit Add missing idr_destroy() call in pps_exit() to properly free the pps_idr radix tree nodes. Without this, module load/unload cycles leak 576-byte radix tree node allocations, detectable by kmemleak as: unreferenced object (size 576): backtrace: [] radix_tree_node_alloc+0xa0/0xf0 [] idr_get_free+0x128/0x280 The pps_idr is initialized via DEFINE_IDR() at line 32 and used throughout the PPS subsystem for device ID management. The fix follows the documented pattern in lib/idr.c and matches the cleanup approach used by other drivers such as drivers/uio/uio.c. This leak was discovered through comprehensive module testing with cumulative kmemleak detection across 10 load/unload iterations per module. Signed-off-by: Anders Roxell --- drivers/pps/pps.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pps/pps.c b/drivers/pps/pps.c index 6a02245ea35f..25ed0d44b121 100644 --- a/drivers/pps/pps.c +++ b/drivers/pps/pps.c @@ -456,6 +456,7 @@ static void __exit pps_exit(void) { class_destroy(pps_class); __unregister_chrdev(pps_major, 0, PPS_MAX_SOURCES, "pps"); + idr_destroy(&pps_idr); } static int __init pps_init(void) -- 2.47.2