thebeanogamer / rpms / qemu-kvm

Forked from rpms/qemu-kvm 5 months ago
Clone

Blame SOURCES/kvm-virtiofsd-Fix-breakage-due-to-fuse_init_in-size-chan.patch

4841a6
From 1da951c4c3b4e403a6c1668a54e6264381c0003d Mon Sep 17 00:00:00 2001
4841a6
From: Vivek Goyal <vgoyal@redhat.com>
4841a6
Date: Tue, 8 Feb 2022 15:48:04 -0500
4841a6
Subject: [PATCH 1/3] virtiofsd: Fix breakage due to fuse_init_in size change
4841a6
4841a6
RH-Author: Dr. David Alan Gilbert <dgilbert@redhat.com>
4841a6
RH-MergeRequest: 193: virtiofsd: Fix breakage due to fuse_init_in size change
4841a6
RH-Commit: [1/1] 5809db034f9361fb462181d71e7cdde1324f8e54
4841a6
RH-Bugzilla: 2097209
4841a6
RH-Acked-by: German Maglione <None>
4841a6
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
4841a6
RH-Acked-by: Vivek Goyal <None>
4841a6
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
4841a6
4841a6
Kernel version 5.17 has increased the size of "struct fuse_init_in" struct.
4841a6
Previously this struct was 16 bytes and now it has been extended to
4841a6
64 bytes in size.
4841a6
4841a6
Once qemu headers are updated to latest, it will expect to receive 64 byte
4841a6
size struct (for protocol version major 7 and minor > 6). But if guest is
4841a6
booting older kernel (older than 5.17), then it still sends older
4841a6
fuse_init_in of size 16 bytes. And do_init() fails. It is expecting
4841a6
64 byte struct. And this results in mount of virtiofs failing.
4841a6
4841a6
Fix this by parsing 16 bytes only for now. Separate patches will be
4841a6
posted which will parse rest of the bytes and enable new functionality.
4841a6
Right now we don't support any of the new functionality, so we don't
4841a6
lose anything by not parsing bytes beyond 16.
4841a6
4841a6
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
4841a6
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
4841a6
Message-Id: <20220208204813.682906-2-vgoyal@redhat.com>
4841a6
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
4841a6
(cherry picked from commit a086d54c6ffa38f7e71f182b63a25315304a3392)
4841a6
---
4841a6
 tools/virtiofsd/fuse_lowlevel.c | 4 +++-
4841a6
 1 file changed, 3 insertions(+), 1 deletion(-)
4841a6
4841a6
diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
4841a6
index e4679c73ab..5d431a7038 100644
4841a6
--- a/tools/virtiofsd/fuse_lowlevel.c
4841a6
+++ b/tools/virtiofsd/fuse_lowlevel.c
4841a6
@@ -1880,6 +1880,8 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid,
4841a6
                     struct fuse_mbuf_iter *iter)
4841a6
 {
4841a6
     size_t compat_size = offsetof(struct fuse_init_in, max_readahead);
4841a6
+    size_t compat2_size = offsetof(struct fuse_init_in, flags) +
4841a6
+                              sizeof(uint32_t);
4841a6
     struct fuse_init_in *arg;
4841a6
     struct fuse_init_out outarg;
4841a6
     struct fuse_session *se = req->se;
4841a6
@@ -1897,7 +1899,7 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid,
4841a6
 
4841a6
     /* ...and now consume the new fields. */
4841a6
     if (arg->major == 7 && arg->minor >= 6) {
4841a6
-        if (!fuse_mbuf_iter_advance(iter, sizeof(*arg) - compat_size)) {
4841a6
+        if (!fuse_mbuf_iter_advance(iter, compat2_size - compat_size)) {
4841a6
             fuse_reply_err(req, EINVAL);
4841a6
             return;
4841a6
         }
4841a6
-- 
4841a6
2.35.3
4841a6