[pve-devel] [PATCH common] tools: add fchownat syscall

[Fabian Grünbichler]

and constant AT_EMPTY_PATH for chowning a directory/file opened via
openat(2), for example when walking/creating a directory tree without
following symlinks.

Signed-off-by: Fabian Grünbichler <f.gruenbichler at proxmox.com>
---
 src/PVE/Syscall.pm | 1 +
 src/PVE/Tools.pm   | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/src/PVE/Syscall.pm b/src/PVE/Syscall.pm
index a2903b7..99e43e7 100644
--- a/src/PVE/Syscall.pm
+++ b/src/PVE/Syscall.pm
@@ -14,6 +14,7 @@ BEGIN {
 	mkdirat => &SYS_mkdirat,
 	faccessat => &SYS_faccessat,
 	setresuid => &SYS_setresuid,
+	fchownat => &SYS_fchownat,
     );
 };
 
diff --git a/src/PVE/Tools.pm b/src/PVE/Tools.pm
index 676647e..550da09 100644
--- a/src/PVE/Tools.pm
+++ b/src/PVE/Tools.pm
@@ -85,6 +85,8 @@ use constant {CLONE_NEWNS   => 0x00020000,
 use constant {O_PATH    => 0x00200000,
               O_TMPFILE => 0x00410000}; # This includes O_DIRECTORY
 
+use constant {AT_EMPTY_PATH => 0x1000};
+
 sub run_with_timeout {
     my ($timeout, $code, @param) = @_;
 
@@ -1556,6 +1558,11 @@ sub mkdirat($$$) {
     return syscall(PVE::Syscall::mkdirat, $dirfd, $name, $mode) == 0;
 }
 
+sub fchownat($$$$$) {
+    my ($dirfd, $pathname, $owner, $group, $flags) = @_;
+    return syscall(PVE::Syscall::fchownat, $dirfd, $pathname, $owner, $group, $flags) == 0;
+}
+
 my $salt_starter = time();
 
 sub encrypt_pw {
-- 
2.20.1