Looks good to me. Maybe change the FYI in the cifs_dbg line above to VFS?
On Fri, Feb 5, 2021 at 6:42 AM Aurélien Aptel aaptel@suse.com wrote:
From: Aurelien Aptel aaptel@suse.com
Assuming
- //HOST/a is mounted on /mnt
- //HOST/b is mounted on /mnt/b
On a slow connection, running 'df' and killing it while it's processing /mnt/b can make cifs_get_inode_info() returns -ERESTARTSYS.
This triggers the following chain of events: => the dentry revalidation fail => dentry is put and released => superblock associated with the dentry is put => /mnt/b is unmounted
This patch makes cifs_d_revalidate() return the error instead of 0 (invalid) when cifs_revalidate_dentry() fails, except for ENOENT (file deleted) and ESTALE (file recreated).
Signed-off-by: Aurelien Aptel aaptel@suse.com Suggested-by: Shyam Prasad N nspmangalore@gmail.com CC: stable@vger.kernel.org
fs/cifs/dir.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index 68900f1629bff..97ac363b5df16 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -737,6 +737,7 @@ static int cifs_d_revalidate(struct dentry *direntry, unsigned int flags) { struct inode *inode;
int rc; if (flags & LOOKUP_RCU) return -ECHILD;@@ -746,8 +747,25 @@ cifs_d_revalidate(struct dentry *direntry, unsigned int flags) if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode))) CIFS_I(inode)->time = 0; /* force reval */
if (cifs_revalidate_dentry(direntry))return 0;
rc = cifs_revalidate_dentry(direntry);if (rc) {cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);switch (rc) {case -ENOENT:case -ESTALE:/** Those errors mean the dentry is invalid* (file was deleted or recreated)*/return 0;default:/** Otherwise some unexpected error happened* report it as-is to VFS layer*/return rc;}} else { /* * If the inode wasn't known to be a dfs entry when-- 2.29.2