From 27f238e0bf1d3abbc4849b2fc93aae8c9c6dc6b3 Mon Sep 17 00:00:00 2001
From: Charan Teja Reddy <quic_charante@quicinc.com>
Date: Tue, 10 May 2022 01:19:57 +0530
Subject: dma-buf: call dma_buf_stats_setup after dmabuf is in valid list
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Git-commit: ef3a6b70507a2add2cd2e01f5eb9b54d561bacb9
Patch-mainline: v5.18-rc7
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
When dma_buf_stats_setup() fails, it closes the dmabuf file which
results into the calling of dma_buf_file_release() where it does
list_del(&dmabuf->list_node) with out first adding it to the proper
list. This is resulting into panic in the below path:
__list_del_entry_valid+0x38/0xac
dma_buf_file_release+0x74/0x158
__fput+0xf4/0x428
____fput+0x14/0x24
task_work_run+0x178/0x24c
do_notify_resume+0x194/0x264
work_pending+0xc/0x5f0
Fix it by moving the dma_buf_stats_setup() after dmabuf is added to the
list.
Fixes: bdb8d06dfefd ("dmabuf: Add the capability to expose DMA-BUF stats in sysfs")
Signed-off-by: Charan Teja Reddy <quic_charante@quicinc.com>
Tested-by: T.J. Mercier <tjmercier@google.com>
Acked-by: T.J. Mercier <tjmercier@google.com>
Cc: <stable@vger.kernel.org> # 5.15.x+
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1652125797-2043-1-git-send-email-quic_charante@quicinc.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/dma-buf/dma-buf.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index df23239b04fc..b1e25ae98302 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -543,10 +543,6 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
file->f_mode |= FMODE_LSEEK;
dmabuf->file = file;
- ret = dma_buf_stats_setup(dmabuf);
- if (ret)
- goto err_sysfs;
-
mutex_init(&dmabuf->lock);
INIT_LIST_HEAD(&dmabuf->attachments);
@@ -554,6 +550,10 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
list_add(&dmabuf->list_node, &db_list.head);
mutex_unlock(&db_list.lock);
+ ret = dma_buf_stats_setup(dmabuf);
+ if (ret)
+ goto err_sysfs;
+
return dmabuf;
err_sysfs:
--
2.38.1