From 36cb0f52aeb929b141f3f580481eb04c65b6e2b9 Mon Sep 17 00:00:00 2001 From: Kemeng Shi Date: Sat, 4 Mar 2023 01:21:06 +0800 Subject: ext4: protect pa->pa_free in ext4_discard_allocated_blocks If ext4_mb_mark_diskspace_used fails in ext4_mb_new_blocks, we may discard pa already in list. Protect pa with pa_lock to avoid race. Signed-off-by: Kemeng Shi Reviewed-by: Ojaswin Mujoo Link: https://lore.kernel.org/r/20230303172120.3800725-7-shikemeng@huaweicloud.com Signed-off-by: Theodore Ts'o --- fs/ext4/mballoc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/ext4') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 0af2ac678170..9d4091fad78d 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4267,8 +4267,11 @@ static void ext4_discard_allocated_blocks(struct ext4_allocation_context *ac) ext4_mb_unload_buddy(&e4b); return; } - if (pa->pa_type == MB_INODE_PA) + if (pa->pa_type == MB_INODE_PA) { + spin_lock(&pa->pa_lock); pa->pa_free += ac->ac_b_ex.fe_len; + spin_unlock(&pa->pa_lock); + } } /* -- cgit v1.2.3-70-g09d2