From 1fb62d581554435800ba339e7f7912cd81d619ba Mon Sep 17 00:00:00 2001
From: Dmitry Vyukov <dvyukov@google.com>
Date: Thu, 9 Aug 2018 16:03:06 +0200
Subject: [PATCH] executor: fix FS_XFLAG_IMMUTABLE for 32-bit mode

FS_IOC_FSSETXATTR is not supported in compat mode, use FS_IOC_SETFLAGS instead.
---
 executor/common_linux.h  | 20 +++++---------------
 pkg/csource/generated.go | 18 +++++-------------
 2 files changed, 10 insertions(+), 28 deletions(-)

diff --git a/executor/common_linux.h b/executor/common_linux.h
index e491c1f9..b5963327 100644
--- a/executor/common_linux.h
+++ b/executor/common_linux.h
@@ -1741,17 +1741,7 @@ static int do_sandbox_namespace(void)
 #include <sys/ioctl.h>
 #include <sys/mount.h>
 
-// This should be in <linux/fs.h> but is not there on some distros/arches as expected.
-struct fsxattr {
-	uint32 fsx_xflags;
-	uint32 fsx_extsize;
-	uint32 fsx_nextents;
-	uint32 fsx_projid;
-	uint32 fsx_cowextsize;
-	char fsx_pad[8];
-};
-
-#define FS_IOC_FSSETXATTR _IOW('X', 32, struct fsxattr)
+#define FS_IOC_SETFLAGS _IOW('f', 2, long)
 
 // One does not simply remove a directory.
 // There can be mounts, so we need to try to umount.
@@ -1803,8 +1793,8 @@ retry:
 				// Try to reset FS_XFLAG_IMMUTABLE.
 				int fd = open(filename, O_RDONLY);
 				if (fd != -1) {
-					struct fsxattr attr = {0};
-					if (ioctl(fd, FS_IOC_FSSETXATTR, &attr) == 0)
+					long flags = 0;
+					if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0)
 						debug("reset FS_XFLAG_IMMUTABLE\n");
 					close(fd);
 					continue;
@@ -1832,8 +1822,8 @@ retry:
 				// Try to reset FS_XFLAG_IMMUTABLE.
 				int fd = open(dir, O_RDONLY);
 				if (fd != -1) {
-					struct fsxattr attr = {0};
-					if (ioctl(fd, FS_IOC_FSSETXATTR, &attr) == 0)
+					long flags = 0;
+					if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0)
 						debug("reset FS_XFLAG_IMMUTABLE\n");
 					close(fd);
 					continue;
diff --git a/pkg/csource/generated.go b/pkg/csource/generated.go
index a5b25001..595a8709 100644
--- a/pkg/csource/generated.go
+++ b/pkg/csource/generated.go
@@ -3218,16 +3218,8 @@ static int do_sandbox_namespace(void)
 #include <string.h>
 #include <sys/ioctl.h>
 #include <sys/mount.h>
-struct fsxattr {
-	uint32 fsx_xflags;
-	uint32 fsx_extsize;
-	uint32 fsx_nextents;
-	uint32 fsx_projid;
-	uint32 fsx_cowextsize;
-	char fsx_pad[8];
-};
 
-#define FS_IOC_FSSETXATTR _IOW('X', 32, struct fsxattr)
+#define FS_IOC_SETFLAGS _IOW('f', 2, long)
 static void remove_dir(const char* dir)
 {
 	DIR* dp;
@@ -3267,8 +3259,8 @@ retry:
 			if (errno == EPERM) {
 				int fd = open(filename, O_RDONLY);
 				if (fd != -1) {
-					struct fsxattr attr = {0};
-					if (ioctl(fd, FS_IOC_FSSETXATTR, &attr) == 0)
+					long flags = 0;
+					if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0)
 						debug("reset FS_XFLAG_IMMUTABLE\n");
 					close(fd);
 					continue;
@@ -3295,8 +3287,8 @@ retry:
 			if (errno == EPERM) {
 				int fd = open(dir, O_RDONLY);
 				if (fd != -1) {
-					struct fsxattr attr = {0};
-					if (ioctl(fd, FS_IOC_FSSETXATTR, &attr) == 0)
+					long flags = 0;
+					if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0)
 						debug("reset FS_XFLAG_IMMUTABLE\n");
 					close(fd);
 					continue;