| Message ID | 20210820132622.4175839-1-vee.khee.wong@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [net] net: stmmac: fix kernel panic due to NULL pointer dereference of plat->est | expand |
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Fri, 20 Aug 2021 21:26:22 +0800 you wrote: > In the case of taprio offload is not enabled, the error handling path > causes a kernel crash due to kernel NULL pointer deference. > > Fix this by adding check for NULL before attempt to access 'plat->est' > on the mutex_lock() call. > > The following kernel panic is observed without this patch: > > [...] Here is the summary with links: - [net] net: stmmac: fix kernel panic due to NULL pointer dereference of plat->est https://git.kernel.org/netdev/net/c/82a44ae113b7 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c index 4f3b6437b114..8160087ee92f 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c @@ -884,11 +884,13 @@ static int tc_setup_taprio(struct stmmac_priv *priv, return 0; disable: - mutex_lock(&priv->plat->est->lock); - priv->plat->est->enable = false; - stmmac_est_configure(priv, priv->ioaddr, priv->plat->est, - priv->plat->clk_ptp_rate); - mutex_unlock(&priv->plat->est->lock); + if (priv->plat->est) { + mutex_lock(&priv->plat->est->lock); + priv->plat->est->enable = false; + stmmac_est_configure(priv, priv->ioaddr, priv->plat->est, + priv->plat->clk_ptp_rate); + mutex_unlock(&priv->plat->est->lock); + } priv->plat->fpe_cfg->enable = false; stmmac_fpe_configure(priv, priv->ioaddr,
In the case of taprio offload is not enabled, the error handling path causes a kernel crash due to kernel NULL pointer deference. Fix this by adding check for NULL before attempt to access 'plat->est' on the mutex_lock() call. The following kernel panic is observed without this patch: RIP: 0010:mutex_lock+0x10/0x20 Call Trace: tc_setup_taprio+0x482/0x560 [stmmac] kmem_cache_alloc_trace+0x13f/0x490 taprio_disable_offload.isra.0+0x9d/0x180 [sch_taprio] taprio_destroy+0x6c/0x100 [sch_taprio] qdisc_create+0x2e5/0x4f0 tc_modify_qdisc+0x126/0x740 rtnetlink_rcv_msg+0x12b/0x380 _raw_spin_lock_irqsave+0x19/0x40 _raw_spin_unlock_irqrestore+0x18/0x30 create_object+0x212/0x340 rtnl_calcit.isra.0+0x110/0x110 netlink_rcv_skb+0x50/0x100 netlink_unicast+0x191/0x230 netlink_sendmsg+0x243/0x470 sock_sendmsg+0x5e/0x60 ____sys_sendmsg+0x20b/0x280 copy_msghdr_from_user+0x5c/0x90 __mod_memcg_state+0x87/0xf0 ___sys_sendmsg+0x7c/0xc0 lru_cache_add+0x7f/0xa0 _raw_spin_unlock+0x16/0x30 wp_page_copy+0x449/0x890 handle_mm_fault+0x921/0xfc0 __sys_sendmsg+0x59/0xa0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ---[ end trace b1f19b24368a96aa ]--- Fixes: b60189e0392f ("net: stmmac: Integrate EST with TAPRIO scheduler API") Cc: <stable@vger.kernel.org> # 5.10.x Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com> --- drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)