Merge tag 'v5.0-rc7' into patchwork

Linux 5.0-rc7

* tag 'v5.0-rc7': (1667 commits)
  Linux 5.0-rc7
  Input: elan_i2c - add ACPI ID for touchpad in Lenovo V330-15ISK
  Input: st-keyscan - fix potential zalloc NULL dereference
  Input: apanel - switch to using brightness_set_blocking()
  powerpc/64s: Fix possible corruption on big endian due to pgd/pud_present()
  efi/arm: Revert "Defer persistent reservations until after paging_init()"
  arm64, mm, efi: Account for GICv3 LPI tables in static memblock reserve table
  sunrpc: fix 4 more call sites that were using stack memory with a scatterlist
  include/linux/module.h: copy __init/__exit attrs to init/cleanup_module
  Compiler Attributes: add support for __copy (gcc >= 9)
  lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure
  auxdisplay: ht16k33: fix potential user-after-free on module unload
  x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls
  i2c: bcm2835: Clear current buffer pointers and counts after a transfer
  i2c: cadence: Fix the hold bit setting
  drm: Use array_size() when creating lease
  dm thin: fix bug where bio that overwrites thin block ignores FUA
  Revert "exec: load_script: don't blindly truncate shebang string"
  Revert "gfs2: read journal in large chunks to locate the head"
  net: ethernet: freescale: set FEC ethtool regs version
  ...

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 15 insertions, 2 deletions

diff --git a/net/ipv6/fou6.c b/net/ipv6/fou6.c
index bd675c61deb1..b858bd5280bf 100644
--- a/net/ipv6/fou6.c
+++ b/net/ipv6/fou6.c
@@ -90,10 +90,11 @@ static int gue6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 {
 	int transport_offset = skb_transport_offset(skb);
 	struct guehdr *guehdr;
-	size_t optlen;
+	size_t len, optlen;
 	int ret;
 
-	if (skb->len < sizeof(struct udphdr) + sizeof(struct guehdr))
+	len = sizeof(struct udphdr) + sizeof(struct guehdr);
+	if (!pskb_may_pull(skb, len))
 		return -EINVAL;
 
 	guehdr = (struct guehdr *)&udp_hdr(skb)[1];
@@ -128,9 +129,21 @@ static int gue6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 
 	optlen = guehdr->hlen << 2;
 
+	if (!pskb_may_pull(skb, len + optlen))
+		return -EINVAL;
+
+	guehdr = (struct guehdr *)&udp_hdr(skb)[1];
 	if (validate_gue_flags(guehdr, optlen))
 		return -EINVAL;
 
+	/* Handling exceptions for direct UDP encapsulation in GUE would lead to
+	 * recursion. Besides, this kind of encapsulation can't even be
+	 * configured currently. Discard this.
+	 */
+	if (guehdr->proto_ctype == IPPROTO_UDP ||
+	    guehdr->proto_ctype == IPPROTO_UDPLITE)
+		return -EOPNOTSUPP;
+
 	skb_set_transport_header(skb, -(int)sizeof(struct icmp6hdr));
 	ret = gue6_err_proto_handler(guehdr->proto_ctype, skb,
 				     opt, type, code, offset, info);