From: bigbrotherwei <1965867461@qq.com>
Date: Wed, 17 Jan 2024 15:58:27 +0000 (+0800)
Subject: Add processing for FUSE_CAP_HANDLE_KILLPRIV and disable it by default
X-Git-Tag: fuse-3.17.1-rc0~156
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=0c12204145d43ad4683136379a130385ef16d166;p=qemu-gpiodev%2Flibfuse.git

Add processing for FUSE_CAP_HANDLE_KILLPRIV and disable it by default

'FUSE_CAP_HANDLE_KILLPRIV' is not enabled by default anymore, as that
would be a sudden security issue introduced by a new ABI and API
compatible libfuse version.
---

diff --git a/include/fuse_common.h b/include/fuse_common.h
index fedbaa9..bdbd7cb 100644
--- a/include/fuse_common.h
+++ b/include/fuse_common.h
@@ -363,7 +363,7 @@ struct fuse_loop_config_v1 {
  * setuid and setgid bits when a file is written, truncated, or
  * its owner is changed.
  *
- * This feature is enabled by default when supported by the kernel.
+ * This feature is disabled by default.
  */
 #define FUSE_CAP_HANDLE_KILLPRIV         (1 << 20)
 
diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c
index d8f5466..def1918 100644
--- a/lib/fuse_lowlevel.c
+++ b/lib/fuse_lowlevel.c
@@ -2054,7 +2054,6 @@ void do_init(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
 		se->conn.want |= (cap)
 	LL_SET_DEFAULT(1, FUSE_CAP_ASYNC_READ);
 	LL_SET_DEFAULT(1, FUSE_CAP_AUTO_INVAL_DATA);
-	LL_SET_DEFAULT(1, FUSE_CAP_HANDLE_KILLPRIV);
 	LL_SET_DEFAULT(1, FUSE_CAP_ASYNC_DIO);
 	LL_SET_DEFAULT(1, FUSE_CAP_IOCTL_DIR);
 	LL_SET_DEFAULT(1, FUSE_CAP_ATOMIC_O_TRUNC);
@@ -2146,6 +2145,8 @@ void do_init(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
 		outargflags |= FUSE_PARALLEL_DIROPS;
 	if (se->conn.want & FUSE_CAP_POSIX_ACL)
 		outargflags |= FUSE_POSIX_ACL;
+	if (se->conn.want & FUSE_CAP_HANDLE_KILLPRIV)
+		outargflags |= FUSE_HANDLE_KILLPRIV;
 	if (se->conn.want & FUSE_CAP_CACHE_SYMLINKS)
 		outargflags |= FUSE_CACHE_SYMLINKS;
 	if (se->conn.want & FUSE_CAP_EXPLICIT_INVAL_DATA)