This is a note to let you know that I've just added the patch titled
NFC: nci: fix memory leak in nci_rx_data_packet()
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfc-nci-fix-memory-leak-in-nci_rx_data_packet.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 886b5b4c1bbdb78823553d4f213b88e6e3124594
Author: Liu Shixin <liushixin2@xxxxxxxxxx>
Date: Fri Nov 18 16:24:19 2022 +0800
NFC: nci: fix memory leak in nci_rx_data_packet()
[ Upstream commit 53270fb0fd77fe786d8c07a0793981d797836b93 ]
Syzbot reported a memory leak about skb:
unreferenced object 0xffff88810e144e00 (size 240):
comm "syz-executor284", pid 3701, jiffies 4294952403 (age 12.620s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff83ab79a9>] __alloc_skb+0x1f9/0x270 net/core/skbuff.c:497
[<ffffffff82a5cf64>] alloc_skb include/linux/skbuff.h:1267 [inline]
[<ffffffff82a5cf64>] virtual_ncidev_write+0x24/0xe0 drivers/nfc/virtual_ncidev.c:116
[<ffffffff815f6503>] do_loop_readv_writev fs/read_write.c:759 [inline]
[<ffffffff815f6503>] do_loop_readv_writev fs/read_write.c:743 [inline]
[<ffffffff815f6503>] do_iter_write+0x253/0x300 fs/read_write.c:863
[<ffffffff815f66ed>] vfs_writev+0xdd/0x240 fs/read_write.c:934
[<ffffffff815f68f6>] do_writev+0xa6/0x1c0 fs/read_write.c:977
[<ffffffff848802d5>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff848802d5>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84a00087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
In nci_rx_data_packet(), if we don't get a valid conn_info, we will return
directly but forget to release the skb.
Reported-by: syzbot+cdb9a427d1bc08815104@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 4aeee6871e8c ("NFC: nci: Add dynamic logical connections support")
Signed-off-by: Liu Shixin <liushixin2@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221118082419.239475-1-liushixin2@xxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/nfc/nci/data.c b/net/nfc/nci/data.c
index 9e3f9460f14f..5d46d8dfad72 100644
--- a/net/nfc/nci/data.c
+++ b/net/nfc/nci/data.c
@@ -291,8 +291,10 @@ void nci_rx_data_packet(struct nci_dev *ndev, struct sk_buff *skb)
nci_plen(skb->data));
conn_info = nci_get_conn_info_by_conn_id(ndev, nci_conn_id(skb->data));
- if (!conn_info)
+ if (!conn_info) {
+ kfree_skb(skb);
return;
+ }
/* strip the nci data header */
skb_pull(skb, NCI_DATA_HDR_SIZE);
