From 89a459e0d519b289c15e4da8f52ff5528c7b8a3c Mon Sep 17 00:00:00 2001 From: Zdenek Kabelac Date: Wed, 8 Nov 2017 13:44:56 +0100 Subject: [PATCH] md: free unused memory after bitmap resize [ Upstream commit 0868b99c214a3d55486c700de7c3f770b7243e7c ] When bitmap is resized, the old kalloced chunks just are not released once the resized bitmap starts to use new space. This fixes in particular kmemleak reports like this one: unreferenced object 0xffff8f4311e9c000 (size 4096): comm "lvm", pid 19333, jiffies 4295263268 (age 528.265s) hex dump (first 32 bytes): 02 80 02 80 02 80 02 80 02 80 02 80 02 80 02 80 ................ 02 80 02 80 02 80 02 80 02 80 02 80 02 80 02 80 ................ backtrace: [] kmemleak_alloc+0x4a/0xa0 [] kmem_cache_alloc_trace+0x14e/0x2e0 [] bitmap_checkpage+0x7c/0x110 [] bitmap_get_counter+0x45/0xd0 [] bitmap_set_memory_bits+0x43/0xe0 [] bitmap_init_from_disk+0x23c/0x530 [] bitmap_load+0xbe/0x160 [] raid_preresume+0x203/0x2f0 [dm_raid] [] dm_table_resume_targets+0x4f/0xe0 [] dm_resume+0x122/0x140 [] dev_suspend+0x18f/0x290 [] ctl_ioctl+0x287/0x560 [] dm_ctl_ioctl+0x13/0x20 [] do_vfs_ioctl+0xa6/0x750 [] SyS_ioctl+0x79/0x90 [] entry_SYSCALL_64_fastpath+0x1f/0xc2 Signed-off-by: Zdenek Kabelac Signed-off-by: Shaohua Li Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/md/bitmap.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index f425905c97fa..0cabf31fb163 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -2158,6 +2158,7 @@ int bitmap_resize(struct bitmap *bitmap, sector_t blocks, for (k = 0; k < page; k++) { kfree(new_bp[k].map); } + kfree(new_bp); /* restore some fields from old_counts */ bitmap->counts.bp = old_counts.bp; @@ -2208,6 +2209,14 @@ int bitmap_resize(struct bitmap *bitmap, sector_t blocks, block += old_blocks; } + if (bitmap->counts.bp != old_counts.bp) { + unsigned long k; + for (k = 0; k < old_counts.pages; k++) + if (!old_counts.bp[k].hijacked) + kfree(old_counts.bp[k].map); + kfree(old_counts.bp); + } + if (!init) { int i; while (block < (chunks << chunkshift)) { -- 2.20.1