nfsd and lockd call vfs_lock_file() to lock/unlock the inode returned by locks_inode(file). Many places in nfsd/lockd code use the inode returned by file_inode(file) for lock manipulation. With Overlayfs, file_inode() (the underlying inode) is not the same object as locks_inode() (the overlay inode). This can result in "Leaked POSIX lock" messages and eventually to a kernel crash as reported by Eddie Horng: https://marc.info/?l=linux-unionfs&m=153086643202072&w=2 Fix all the call sites in nfsd/lockd that should use locks_inode(). This is a correctness bug that manifested when overlayfs gained NFS export support in v4.16. Reported-by: Eddie Horng <eddiehorng.tw@xxxxxxxxx> Tested-by: Eddie Horng <eddiehorng.tw@xxxxxxxxx> Cc: Jeff Layton <jlayton@xxxxxxxxxx> Fixes: 8383f1748829 ("ovl: wire up NFS export operations") Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- Hi Bruce, For the purpose of locks, nfsd/lockd should look at locks_inode() just like vfs lock functions. Hopefully, Miklos's work on stacked overlayfs file operations will be merged soon and locks_inode() will become the same as file_inode(), but we will still need this fix for stable kernels v4.16 through v4.18. Beyond testing by Eddie, I also verified no regressions when running nfstest with exported overlayfs. Thanks, Amir. fs/lockd/clntlock.c | 2 +- fs/lockd/clntproc.c | 2 +- fs/lockd/svclock.c | 16 ++++++++-------- fs/lockd/svcsubs.c | 4 ++-- fs/nfsd/nfs4state.c | 2 +- include/linux/lockd/lockd.h | 4 ++-- 6 files changed, 15 insertions(+), 15 deletions(-) diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c index 96c1d14c18f1..c2a128678e6e 100644 --- a/fs/lockd/clntlock.c +++ b/fs/lockd/clntlock.c @@ -187,7 +187,7 @@ __be32 nlmclnt_grant(const struct sockaddr *addr, const struct nlm_lock *lock) continue; if (!rpc_cmp_addr(nlm_addr(block->b_host), addr)) continue; - if (nfs_compare_fh(NFS_FH(file_inode(fl_blocked->fl_file)) ,fh) != 0) + if (nfs_compare_fh(NFS_FH(locks_inode(fl_blocked->fl_file)), fh) != 0) continue; /* Alright, we found a lock. Set the return status * and wake up the caller diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index a2c0dfc6fdc0..d20b92f271c2 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -128,7 +128,7 @@ static void nlmclnt_setlockargs(struct nlm_rqst *req, struct file_lock *fl) char *nodename = req->a_host->h_rpcclnt->cl_nodename; nlmclnt_next_cookie(&argp->cookie); - memcpy(&lock->fh, NFS_FH(file_inode(fl->fl_file)), sizeof(struct nfs_fh)); + memcpy(&lock->fh, NFS_FH(locks_inode(fl->fl_file)), sizeof(struct nfs_fh)); lock->caller = nodename; lock->oh.data = req->a_owner; lock->oh.len = snprintf(req->a_owner, sizeof(req->a_owner), "%u@%s", diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index 3701bccab478..74330daeab71 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -405,8 +405,8 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file, __be32 ret; dprintk("lockd: nlmsvc_lock(%s/%ld, ty=%d, pi=%d, %Ld-%Ld, bl=%d)\n", - file_inode(file->f_file)->i_sb->s_id, - file_inode(file->f_file)->i_ino, + locks_inode(file->f_file)->i_sb->s_id, + locks_inode(file->f_file)->i_ino, lock->fl.fl_type, lock->fl.fl_pid, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end, @@ -511,8 +511,8 @@ nlmsvc_testlock(struct svc_rqst *rqstp, struct nlm_file *file, __be32 ret; dprintk("lockd: nlmsvc_testlock(%s/%ld, ty=%d, %Ld-%Ld)\n", - file_inode(file->f_file)->i_sb->s_id, - file_inode(file->f_file)->i_ino, + locks_inode(file->f_file)->i_sb->s_id, + locks_inode(file->f_file)->i_ino, lock->fl.fl_type, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end); @@ -566,8 +566,8 @@ nlmsvc_unlock(struct net *net, struct nlm_file *file, struct nlm_lock *lock) int error; dprintk("lockd: nlmsvc_unlock(%s/%ld, pi=%d, %Ld-%Ld)\n", - file_inode(file->f_file)->i_sb->s_id, - file_inode(file->f_file)->i_ino, + locks_inode(file->f_file)->i_sb->s_id, + locks_inode(file->f_file)->i_ino, lock->fl.fl_pid, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end); @@ -595,8 +595,8 @@ nlmsvc_cancel_blocked(struct net *net, struct nlm_file *file, struct nlm_lock *l int status = 0; dprintk("lockd: nlmsvc_cancel(%s/%ld, pi=%d, %Ld-%Ld)\n", - file_inode(file->f_file)->i_sb->s_id, - file_inode(file->f_file)->i_ino, + locks_inode(file->f_file)->i_sb->s_id, + locks_inode(file->f_file)->i_ino, lock->fl.fl_pid, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end); diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c index 4ec3d6e03e76..899360ba3b84 100644 --- a/fs/lockd/svcsubs.c +++ b/fs/lockd/svcsubs.c @@ -44,7 +44,7 @@ static inline void nlm_debug_print_fh(char *msg, struct nfs_fh *f) static inline void nlm_debug_print_file(char *msg, struct nlm_file *file) { - struct inode *inode = file_inode(file->f_file); + struct inode *inode = locks_inode(file->f_file); dprintk("lockd: %s %s/%ld\n", msg, inode->i_sb->s_id, inode->i_ino); @@ -414,7 +414,7 @@ nlmsvc_match_sb(void *datap, struct nlm_file *file) { struct super_block *sb = datap; - return sb == file_inode(file->f_file)->i_sb; + return sb == locks_inode(file->f_file)->i_sb; } /** diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 857141446d6b..4a17fad93411 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -6293,7 +6293,7 @@ check_for_locks(struct nfs4_file *fp, struct nfs4_lockowner *lowner) return status; } - inode = file_inode(filp); + inode = locks_inode(filp); flctx = inode->i_flctx; if (flctx && !list_empty_careful(&flctx->flc_posix)) { diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index 4fd95dbeb52f..b065ef406770 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -299,7 +299,7 @@ int nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr); static inline struct inode *nlmsvc_file_inode(struct nlm_file *file) { - return file_inode(file->f_file); + return locks_inode(file->f_file); } static inline int __nlm_privileged_request4(const struct sockaddr *sap) @@ -359,7 +359,7 @@ static inline int nlm_privileged_requester(const struct svc_rqst *rqstp) static inline int nlm_compare_locks(const struct file_lock *fl1, const struct file_lock *fl2) { - return file_inode(fl1->fl_file) == file_inode(fl2->fl_file) + return locks_inode(fl1->fl_file) == locks_inode(fl2->fl_file) && fl1->fl_pid == fl2->fl_pid && fl1->fl_owner == fl2->fl_owner && fl1->fl_start == fl2->fl_start -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
