From c58dc5a1f886f2fcc1133746d0cbaa1fe7fd44ff Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Tue, 2 Jul 2024 14:28:46 +0100 Subject: [PATCH] coresight: tmc: sg: Do not leak sg_table Running perf with cs_etm on Juno triggers the following kmemleak warning ! :~# cat /sys/kernel/debug/kmemleak unreferenced object 0xffffff8806b6d720 (size 96): comm "perf", pid 562, jiffies 4297810960 hex dump (first 32 bytes): 38 d8 13 07 88 ff ff ff 00 d0 9e 85 c0 ff ff ff 8............... 00 10 00 88 c0 ff ff ff 00 f0 ff f7 ff 00 00 00 ................ backtrace (crc 1dbf6e00): [] kmemleak_alloc+0xbc/0xd8 [] kmalloc_trace_noprof+0x220/0x2e8 [] tmc_alloc_sg_table+0x48/0x208 [coresight_tmc] [] tmc_etr_alloc_sg_buf+0xac/0x240 [coresight_tmc] [] tmc_alloc_etr_buf.constprop.0+0x1f0/0x260 [coresight_tmc] [] alloc_etr_buf.constprop.0.isra.0+0x74/0xa8 [coresight_tmc] [] tmc_alloc_etr_buffer+0x110/0x260 [coresight_tmc] [] etm_setup_aux+0x204/0x3b0 [coresight] [] rb_alloc_aux+0x20c/0x318 [] perf_mmap+0x2e4/0x7a0 [] mmap_region+0x3b0/0xa08 [] do_mmap+0x3a0/0x500 [] vm_mmap_pgoff+0x100/0x1d0 [] ksys_mmap_pgoff+0xb8/0x110 [] __arm64_sys_mmap+0x38/0x58 [] invoke_syscall.constprop.0+0x58/0x100 This due to the fact that we do not free the "sg_table" itself while freeing up the SG table and data pages. Fix this by freeing the sg_table in tmc_free_sg_table(). Fixes: 99443ea19e8b ("coresight: Add generic TMC sg table framework") Cc: Mike Leach Cc: James Clark Signed-off-by: Suzuki K Poulose Reviewed-by: Anshuman Khandual Link: https://lore.kernel.org/r/20240702132846.1677261-1-suzuki.poulose@arm.com --- drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index e75428fa1592..610ad51cda65 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -261,6 +261,7 @@ void tmc_free_sg_table(struct tmc_sg_table *sg_table) { tmc_free_table_pages(sg_table); tmc_free_data_pages(sg_table); + kfree(sg_table); } EXPORT_SYMBOL_GPL(tmc_free_sg_table); @@ -342,7 +343,6 @@ struct tmc_sg_table *tmc_alloc_sg_table(struct device *dev, rc = tmc_alloc_table_pages(sg_table); if (rc) { tmc_free_sg_table(sg_table); - kfree(sg_table); return ERR_PTR(rc); }