[PATCH] fs/9p: Fix bit operation logic error

From: Eric Van Hensbergen
Date: Wed Apr 26 2023 - 12:31:29 EST


This re-introduces a fix that somehow got dropped during rebase of the
current series in for-next. When writeback is enabled, opens
are forced to support both read and write operations but with the
logic error other flags may be dropped unintentionaly.

Reported-by: Christophe Jaillet <christophe.jaillet@xxxxxxxxxx>
Signed-off-by: Eric Van Hensbergen <ericvh@xxxxxxxxxx>
---
fs/9p/vfs_inode.c | 2 +-
fs/9p/vfs_inode_dotl.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 54dfe4f10f43..3791f642c502 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -823,7 +823,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
p9_omode = v9fs_uflags2omode(flags, v9fs_proto_dotu(v9ses));

if ((v9ses->cache & CACHE_WRITEBACK) && (p9_omode & P9_OWRITE)) {
- p9_omode = (p9_omode & !P9_OWRITE) | P9_ORDWR;
+ p9_omode = (p9_omode & ~P9_OWRITE) | P9_ORDWR;
p9_debug(P9_DEBUG_CACHE,
"write-only file with writeback enabled, creating w/ O_RDWR\n");
}
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index f9371b5b70ea..3acf2bcb69cc 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -288,7 +288,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
}

if ((v9ses->cache & CACHE_WRITEBACK) && (p9_omode & P9_OWRITE)) {
- p9_omode = (p9_omode & !P9_OWRITE) | P9_ORDWR;
+ p9_omode = (p9_omode & ~P9_OWRITE) | P9_ORDWR;
p9_debug(P9_DEBUG_CACHE,
"write-only file with writeback enabled, creating w/ O_RDWR\n");
}

---
base-commit: 4eb3117888a923f6b9b1ad2dd093641c49a63ae5
change-id: 20230426-fix-bitops-c862099c8d28

Best regards,
--
Eric Van Hensbergen <ericvh@xxxxxxxxxx>