Merge tag 'net-6.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Paolo Abeni:
 "Including fixes from CAN and BPF.

  We have a regression in TC currently under investigation, otherwise
  the things that stand off most are probably the TCP and AF_PACKET
  fixes, with both issues coming from 6.5.

  Previous releases - regressions:

   - af_packet: fix fortified memcpy() without flex array.

   - tcp: fix crashes trying to free half-baked MTU probes

   - xdp: fix zero-size allocation warning in xskq_create()

   - can: sja1000: always restart the tx queue after an overrun

   - eth: mlx5e: again mutually exclude RX-FCS and RX-port-timestamp

   - eth: nfp: avoid rmmod nfp crash issues

   - eth: octeontx2-pf: fix page pool frag allocation warning

  Previous releases - always broken:

   - mctp: perform route lookups under a RCU read-side lock

   - bpf: s390: fix clobbering the caller's backchain in the trampoline

   - phy: lynx-28g: cancel the CDR check work item on the remove path

   - dsa: qca8k: fix qca8k driver for Turris 1.x

   - eth: ravb: fix use-after-free issue in ravb_tx_timeout_work()

   - eth: ixgbe: fix crash with empty VF macvlan list"

* tag 'net-6.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (54 commits)
  rswitch: Fix imbalance phy_power_off() calling
  rswitch: Fix renesas_eth_sw_remove() implementation
  octeontx2-pf: Fix page pool frag allocation warning
  nfc: nci: assert requested protocol is valid
  af_packet: Fix fortified memcpy() without flex array.
  net: tcp: fix crashes trying to free half-baked MTU probes
  net/smc: Fix pos miscalculation in statistics
  nfp: flower: avoid rmmod nfp crash issues
  net: usb: dm9601: fix uninitialized variable use in dm9601_mdio_read
  ethtool: Fix mod state of verbose no_mask bitset
  net: nfc: fix races in nfc_llcp_sock_get() and nfc_llcp_sock_get_sn()
  mctp: perform route lookups under a RCU read-side lock
  net: skbuff: fix kernel-doc typos
  s390/bpf: Fix unwinding past the trampoline
  s390/bpf: Fix clobbering the caller's backchain in the trampoline
  net/mlx5e: Again mutually exclude RX-FCS and RX-port-timestamp
  net/smc: Fix dependency of SMC on ISM
  ixgbe: fix crash with empty VF macvlan list
  net/mlx5e: macsec: use update_pn flag instead of PN comparation
  net: phy: mscc: macsec: reject PN update requests
  ...

1 files changed, 20 insertions, 5 deletions

diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 2861e3360aff..e507692e51e7 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -2066,6 +2066,7 @@ struct bpf_tramp_jit {
 				 * func_addr's original caller
 				 */
 	int stack_size;		/* Trampoline stack size */
+	int backchain_off;	/* Offset of backchain */
 	int stack_args_off;	/* Offset of stack arguments for calling
 				 * func_addr, has to be at the top
 				 */
@@ -2086,9 +2087,10 @@ struct bpf_tramp_jit {
 				 * for __bpf_prog_enter() return value and
 				 * func_addr respectively
 				 */
-	int r14_off;		/* Offset of saved %r14 */
 	int run_ctx_off;	/* Offset of struct bpf_tramp_run_ctx */
 	int tccnt_off;		/* Offset of saved tailcall counter */
+	int r14_off;		/* Offset of saved %r14, has to be at the
+				 * bottom */
 	int do_fexit;		/* do_fexit: label */
 };
 
@@ -2247,8 +2249,12 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
 	 * Calculate the stack layout.
 	 */
 
-	/* Reserve STACK_FRAME_OVERHEAD bytes for the callees. */
+	/*
+	 * Allocate STACK_FRAME_OVERHEAD bytes for the callees. As the s390x
+	 * ABI requires, put our backchain at the end of the allocated memory.
+	 */
 	tjit->stack_size = STACK_FRAME_OVERHEAD;
+	tjit->backchain_off = tjit->stack_size - sizeof(u64);
 	tjit->stack_args_off = alloc_stack(tjit, nr_stack_args * sizeof(u64));
 	tjit->reg_args_off = alloc_stack(tjit, nr_reg_args * sizeof(u64));
 	tjit->ip_off = alloc_stack(tjit, sizeof(u64));
@@ -2256,16 +2262,25 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
 	tjit->bpf_args_off = alloc_stack(tjit, nr_bpf_args * sizeof(u64));
 	tjit->retval_off = alloc_stack(tjit, sizeof(u64));
 	tjit->r7_r8_off = alloc_stack(tjit, 2 * sizeof(u64));
-	tjit->r14_off = alloc_stack(tjit, sizeof(u64));
 	tjit->run_ctx_off = alloc_stack(tjit,
 					sizeof(struct bpf_tramp_run_ctx));
 	tjit->tccnt_off = alloc_stack(tjit, sizeof(u64));
-	/* The caller has already reserved STACK_FRAME_OVERHEAD bytes. */
-	tjit->stack_size -= STACK_FRAME_OVERHEAD;
+	tjit->r14_off = alloc_stack(tjit, sizeof(u64) * 2);
+	/*
+	 * In accordance with the s390x ABI, the caller has allocated
+	 * STACK_FRAME_OVERHEAD bytes for us. 8 of them contain the caller's
+	 * backchain, and the rest we can use.
+	 */
+	tjit->stack_size -= STACK_FRAME_OVERHEAD - sizeof(u64);
 	tjit->orig_stack_args_off = tjit->stack_size + STACK_FRAME_OVERHEAD;
 
+	/* lgr %r1,%r15 */
+	EMIT4(0xb9040000, REG_1, REG_15);
 	/* aghi %r15,-stack_size */
 	EMIT4_IMM(0xa70b0000, REG_15, -tjit->stack_size);
+	/* stg %r1,backchain_off(%r15) */
+	EMIT6_DISP_LH(0xe3000000, 0x0024, REG_1, REG_0, REG_15,
+		      tjit->backchain_off);
 	/* mvc tccnt_off(4,%r15),stack_size+STK_OFF_TCCNT(%r15) */
 	_EMIT6(0xd203f000 | tjit->tccnt_off,
 	       0xf000 | (tjit->stack_size + STK_OFF_TCCNT));