| Message ID | 20210824160015.979155-1-yoong.siang.song@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,1/1] net: stmmac: fix kernel panic due to NULL pointer dereference of buf->xdp | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 6 maintainers not CCed: andrii@kernel.org kafai@fb.com yhs@fb.com songliubraving@fb.com alexandre.torgue@foss.st.com kpsingh@kernel.org |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 20 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 7b8404a21544..fa90bcdf4e45 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4914,6 +4914,10 @@ static int stmmac_rx_zc(struct stmmac_priv *priv, int limit, u32 queue) prefetch(np); + /* Ensure a valid XSK buffer before proceed */ + if (!buf->xdp) + break; + if (priv->extend_desc) stmmac_rx_extended_status(priv, &priv->dev->stats, &priv->xstats, @@ -4934,10 +4938,6 @@ static int stmmac_rx_zc(struct stmmac_priv *priv, int limit, u32 queue) continue; } - /* Ensure a valid XSK buffer before proceed */ - if (!buf->xdp) - break; - /* XSK pool expects RX frame 1:1 mapped to XSK buffer */ if (likely(status & rx_not_ls)) { xsk_buff_free(buf->xdp);
Ensure a valid XSK buffer before proceed to free the xdp buffer. The following kernel panic is observed without this patch: RIP: 0010:xp_free+0x5/0x40 Call Trace: stmmac_napi_poll_rxtx+0x332/0xb30 [stmmac] ? stmmac_tx_timer+0x3c/0xb0 [stmmac] net_rx_action+0x13d/0x3d0 __do_softirq+0xfc/0x2fb ? smpboot_register_percpu_thread+0xe0/0xe0 run_ksoftirqd+0x32/0x70 smpboot_thread_fn+0x1d8/0x2c0 kthread+0x169/0x1a0 ? kthread_park+0x90/0x90 ret_from_fork+0x1f/0x30 ---[ end trace 0000000000000002 ]--- Fixes: bba2556efad6 ("net: stmmac: Enable RX via AF_XDP zero-copy") Cc: <stable@vger.kernel.org> # 5.13.x Suggested-by: Ong Boon Leong <boon.leong.ong@intel.com> Signed-off-by: Song Yoong Siang <yoong.siang.song@intel.com> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)