From: Dan Carpenter dan.carpenter@linaro.org

stable inclusion from stable-v4.19.320 commit 70db2c84631f50e02e6b32b543700699dd395803 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAKPV2 CVE: CVE-2024-42280

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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[ 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@linaro.org Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/8be65f5a-c2dd-4ba0-8a10-bfe5980b8cfb@stanley.mounta... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zhang Changzhong zhangchangzhong@huawei.com --- drivers/isdn/hardware/mISDN/hfcmulti.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/isdn/hardware/mISDN/hfcmulti.c b/drivers/isdn/hardware/mISDN/hfcmulti.c index 0928fd1..c03ded7 100644 --- a/drivers/isdn/hardware/mISDN/hfcmulti.c +++ b/drivers/isdn/hardware/mISDN/hfcmulti.c @@ -1945,7 +1945,7 @@ 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; @@ -2166,14 +2166,15 @@ 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; }