unix: update glibc to 2.43

Change-Id: Iba1e8753f68af6ac6ee741953b1efdb24183a204
GitHub-Last-Rev: ec88943ac752989571ab2713a8fff4a25070610f
GitHub-Pull-Request: golang/sys#280
Reviewed-on: https://go-review.googlesource.com/c/sys/+/790440
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
LUCI-TryBot-Result: golang-scoped@luci-project-accounts.iam.gserviceaccount.com <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
diff --git a/unix/linux/Dockerfile b/unix/linux/Dockerfile
index 226600f..8c35ef0 100644
--- a/unix/linux/Dockerfile
+++ b/unix/linux/Dockerfile
@@ -17,8 +17,8 @@
 RUN git config --global advice.detachedHead false
 # Linux Kernel: Released 13 Apr 2026
 RUN git clone --branch v7.0 --depth 1 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
-# GNU C library: Released 29 Jan 2025
-RUN git clone --branch release/2.41/master --depth 1 https://sourceware.org/git/glibc.git
+# GNU C library: Released 23 Jan 2026
+RUN git clone --branch release/2.43/master --depth 1 https://sourceware.org/git/glibc.git
 
 # Get Go
 ENV GOLANG_VERSION=1.25.1
diff --git a/unix/zerrors_linux.go b/unix/zerrors_linux.go
index 9d72a6b..5bb51d7 100644
--- a/unix/zerrors_linux.go
+++ b/unix/zerrors_linux.go
@@ -1359,6 +1359,7 @@
 	FAN_UNLIMITED_MARKS                         = 0x20
 	FAN_UNLIMITED_QUEUE                         = 0x10
 	FD_CLOEXEC                                  = 0x1
+	FD_PIDFS_ROOT                               = -0x2712
 	FD_SETSIZE                                  = 0x400
 	FF0                                         = 0x0
 	FIB_RULE_DEV_DETACHED                       = 0x8
@@ -1970,6 +1971,8 @@
 	MADV_DONTNEED                               = 0x4
 	MADV_DONTNEED_LOCKED                        = 0x18
 	MADV_FREE                                   = 0x8
+	MADV_GUARD_INSTALL                          = 0x66
+	MADV_GUARD_REMOVE                           = 0x67
 	MADV_HUGEPAGE                               = 0xe
 	MADV_HWPOISON                               = 0x64
 	MADV_KEEPONFORK                             = 0x13
@@ -2114,7 +2117,7 @@
 	MS_NOSEC                                    = 0x10000000
 	MS_NOSUID                                   = 0x2
 	MS_NOSYMFOLLOW                              = 0x100
-	MS_NOUSER                                   = -0x80000000
+	MS_NOUSER                                   = 0x80000000
 	MS_POSIXACL                                 = 0x10000
 	MS_PRIVATE                                  = 0x40000
 	MS_RDONLY                                   = 0x1
@@ -3786,6 +3789,9 @@
 	TCPOPT_TIMESTAMP                            = 0x8
 	TCPOPT_TSTAMP_HDR                           = 0x101080a
 	TCPOPT_WINDOW                               = 0x3
+	TCP_AO_KEYF_EXCLUDE_OPT                     = 0x2
+	TCP_AO_KEYF_IFINDEX                         = 0x1
+	TCP_AO_MAXKEYLEN                            = 0x50
 	TCP_CC_INFO                                 = 0x1a
 	TCP_CM_INQ                                  = 0x24
 	TCP_CONGESTION                              = 0xd