This is a note to let you know that I've just added the patch titled
mISDN: Fix a use after free in hfcmulti_tx()
to the 5.4-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:
misdn-fix-a-use-after-free-in-hfcmulti_tx.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d821b2eb81c1e849278f5b1cd0ec54c4ab676938
Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Wed Jul 24 11:08:18 2024 -0500
mISDN: Fix a use after free in hfcmulti_tx()
[ Upstream commit 61ab751451f5ebd0b98e02276a44e23a10110402 ]
Don't dereference *sp after calling dev_kfree_skb(*sp).
Fixes: af69fb3a8ffa ("Add mISDN HFC multiport driver")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Link: https://patch.msgid.link/8be65f5a-c2dd-4ba0-8a10-bfe5980b8cfb@stanley.mountain
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c
index 2c74064652334..6e09975613300 100644
--- a/drivers/isdn/hardware/mISDN/hfcmulti.c
+++ b/drivers/isdn/hardware/mISDN/hfcmulti.c
@@ -1931,7 +1931,7 @@ hfcmulti_dtmf(struct hfc_multi *hc)
static void
hfcmulti_tx(struct hfc_multi *hc, int ch)
{
- int i, ii, temp, len = 0;
+ int i, ii, temp, tmp_len, len = 0;
int Zspace, z1, z2; /* must be int for calculation */
int Fspace, f1, f2;
u_char *d;
@@ -2152,14 +2152,15 @@ hfcmulti_tx(struct hfc_multi *hc, int ch)
HFC_wait_nodebug(hc);
}
+ tmp_len = (*sp)->len;
dev_kfree_skb(*sp);
/* check for next frame */
if (bch && get_next_bframe(bch)) {
- len = (*sp)->len;
+ len = tmp_len;
goto next_frame;
}
if (dch && get_next_dframe(dch)) {
- len = (*sp)->len;
+ len = tmp_len;
goto next_frame;
}
