[PATCH 5.15 817/917] nfc: pn533: Fix double free when pn533_fill_fragment_skbs() fails
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-11-16 00:36:35
Also in:
lkml
Subsystem:
nfc subsystem, the rest · Maintainers:
David Heidelberg, Linus Torvalds
From: Chengfeng Ye <redacted>
[ Upstream commit 9fec40f850658e00a14a7dd9e06f7fbc7e59cc4a ]
skb is already freed by dev_kfree_skb in pn533_fill_fragment_skbs,
but follow error handler branch when pn533_fill_fragment_skbs()
fails, skb is freed again, results in double free issue. Fix this
by not free skb in error path of pn533_fill_fragment_skbs.
Fixes: 963a82e07d4e ("NFC: pn533: Split large Tx frames in chunks")
Fixes: 93ad42020c2d ("NFC: pn533: Target mode Tx fragmentation support")
Signed-off-by: Chengfeng Ye <redacted>
Reviewed-by: Dan Carpenter <redacted>
Reviewed-by: Krzysztof Kozlowski <redacted>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/nfc/pn533/pn533.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/nfc/pn533/pn533.c b/drivers/nfc/pn533/pn533.c
index 2f3f3fe9a0baa..d32aec0c334fe 100644
--- a/drivers/nfc/pn533/pn533.c
+++ b/drivers/nfc/pn533/pn533.c@@ -2218,7 +2218,7 @@ static int pn533_fill_fragment_skbs(struct pn533 *dev, struct sk_buff *skb) frag = pn533_alloc_skb(dev, frag_size); if (!frag) { skb_queue_purge(&dev->fragment_skb); - break; + return -ENOMEM; } if (!dev->tgt_mode) {
@@ -2287,7 +2287,7 @@ static int pn533_transceive(struct nfc_dev *nfc_dev, /* jumbo frame ? */ if (skb->len > PN533_CMD_DATAEXCH_DATA_MAXLEN) { rc = pn533_fill_fragment_skbs(dev, skb); - if (rc <= 0) + if (rc < 0) goto error; skb = skb_dequeue(&dev->fragment_skb);
@@ -2355,7 +2355,7 @@ static int pn533_tm_send(struct nfc_dev *nfc_dev, struct sk_buff *skb) /* let's split in multiple chunks if size's too big */ if (skb->len > PN533_CMD_DATAEXCH_DATA_MAXLEN) { rc = pn533_fill_fragment_skbs(dev, skb); - if (rc <= 0) + if (rc < 0) goto error; /* get the first skb */
--
2.33.0