From 373c3b80e459cb57c34381b928588a3794eb5bbd Mon Sep 17 00:00:00 2001
From: Johannes Thumshirn <jthumshirn@suse.de>
Date: Mon, 15 Jul 2019 15:16:12 +0200
Subject: [PATCH] btrfs: don't leak extent_map in btrfs_get_io_geometry()
btrfs_get_io_geometry() calls btrfs_get_chunk_map() to acquire a reference
on a extent_map, but on normal operation it does not drop this reference
anymore.
This leads to excessive kmemleak reports.
Always call free_extent_map(), not just in the error case.
Fixes: 5f1411265e16 ("btrfs: Introduce btrfs_io_geometry infrastructure")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/volumes.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index a13ddba1ebc3b..d74b74ca07afd 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5941,6 +5941,7 @@ int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
u64 stripe_len;
u64 raid56_full_stripe_start = (u64)-1;
int data_stripes;
+ int ret = 0;
ASSERT(op != BTRFS_MAP_DISCARD);
@@ -5961,8 +5962,8 @@ int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
btrfs_crit(fs_info,
"stripe math has gone wrong, stripe_offset=%llu offset=%llu start=%llu logical=%llu stripe_len=%llu",
stripe_offset, offset, em->start, logical, stripe_len);
- free_extent_map(em);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
/* stripe_offset is the offset of this block in its stripe */
@@ -6009,7 +6010,10 @@ int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
io_geom->stripe_offset = stripe_offset;
io_geom->raid56_stripe_offset = raid56_full_stripe_start;
- return 0;
+out:
+ /* once for us */
+ free_extent_map(em);
+ return ret;
}
static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
--
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