From 776dc4b1650062099df3cb4f90fa01c8e73eecfa Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Tue, 8 Feb 2022 15:48:06 -0500 Subject: [PATCH] virtiofsd: Parse extended "struct fuse_init_in" Add some code to parse extended "struct fuse_init_in". And use a local variable "flag" to represent 64 bit flags. This will make it easier to add more features without having to worry about two 32bit flags (->flags and ->flags2) in "fuse_struct_in". Signed-off-by: Vivek Goyal Message-Id: <20220208204813.682906-4-vgoyal@redhat.com> Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Dr. David Alan Gilbert dgilbert: Fixed up long line --- tools/virtiofsd/fuse_lowlevel.c | 61 +++++++++++++++++++++------------ 1 file changed, 39 insertions(+), 22 deletions(-) diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c index 5d431a7038..03d60f462a 100644 --- a/tools/virtiofsd/fuse_lowlevel.c +++ b/tools/virtiofsd/fuse_lowlevel.c @@ -1882,11 +1882,14 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, size_t compat_size = offsetof(struct fuse_init_in, max_readahead); size_t compat2_size = offsetof(struct fuse_init_in, flags) + sizeof(uint32_t); + /* Fuse structure extended with minor version 36 */ + size_t compat3_size = endof(struct fuse_init_in, unused); struct fuse_init_in *arg; struct fuse_init_out outarg; struct fuse_session *se = req->se; size_t bufsize = se->bufsize; size_t outargsize = sizeof(outarg); + uint64_t flags = 0; (void)nodeid; @@ -1903,11 +1906,25 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, fuse_reply_err(req, EINVAL); return; } + flags |= arg->flags; + } + + /* + * fuse_init_in was extended again with minor version 36. Just read + * current known size of fuse_init so that future extension and + * header rebase does not cause breakage. + */ + if (sizeof(*arg) > compat2_size && (arg->flags & FUSE_INIT_EXT)) { + if (!fuse_mbuf_iter_advance(iter, compat3_size - compat2_size)) { + fuse_reply_err(req, EINVAL); + return; + } + flags |= (uint64_t) arg->flags2 << 32; } fuse_log(FUSE_LOG_DEBUG, "INIT: %u.%u\n", arg->major, arg->minor); if (arg->major == 7 && arg->minor >= 6) { - fuse_log(FUSE_LOG_DEBUG, "flags=0x%08x\n", arg->flags); + fuse_log(FUSE_LOG_DEBUG, "flags=0x%016llx\n", flags); fuse_log(FUSE_LOG_DEBUG, "max_readahead=0x%08x\n", arg->max_readahead); } se->conn.proto_major = arg->major; @@ -1935,68 +1952,68 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, if (arg->max_readahead < se->conn.max_readahead) { se->conn.max_readahead = arg->max_readahead; } - if (arg->flags & FUSE_ASYNC_READ) { + if (flags & FUSE_ASYNC_READ) { se->conn.capable |= FUSE_CAP_ASYNC_READ; } - if (arg->flags & FUSE_POSIX_LOCKS) { + if (flags & FUSE_POSIX_LOCKS) { se->conn.capable |= FUSE_CAP_POSIX_LOCKS; } - if (arg->flags & FUSE_ATOMIC_O_TRUNC) { + if (flags & FUSE_ATOMIC_O_TRUNC) { se->conn.capable |= FUSE_CAP_ATOMIC_O_TRUNC; } - if (arg->flags & FUSE_EXPORT_SUPPORT) { + if (flags & FUSE_EXPORT_SUPPORT) { se->conn.capable |= FUSE_CAP_EXPORT_SUPPORT; } - if (arg->flags & FUSE_DONT_MASK) { + if (flags & FUSE_DONT_MASK) { se->conn.capable |= FUSE_CAP_DONT_MASK; } - if (arg->flags & FUSE_FLOCK_LOCKS) { + if (flags & FUSE_FLOCK_LOCKS) { se->conn.capable |= FUSE_CAP_FLOCK_LOCKS; } - if (arg->flags & FUSE_AUTO_INVAL_DATA) { + if (flags & FUSE_AUTO_INVAL_DATA) { se->conn.capable |= FUSE_CAP_AUTO_INVAL_DATA; } - if (arg->flags & FUSE_DO_READDIRPLUS) { + if (flags & FUSE_DO_READDIRPLUS) { se->conn.capable |= FUSE_CAP_READDIRPLUS; } - if (arg->flags & FUSE_READDIRPLUS_AUTO) { + if (flags & FUSE_READDIRPLUS_AUTO) { se->conn.capable |= FUSE_CAP_READDIRPLUS_AUTO; } - if (arg->flags & FUSE_ASYNC_DIO) { + if (flags & FUSE_ASYNC_DIO) { se->conn.capable |= FUSE_CAP_ASYNC_DIO; } - if (arg->flags & FUSE_WRITEBACK_CACHE) { + if (flags & FUSE_WRITEBACK_CACHE) { se->conn.capable |= FUSE_CAP_WRITEBACK_CACHE; } - if (arg->flags & FUSE_NO_OPEN_SUPPORT) { + if (flags & FUSE_NO_OPEN_SUPPORT) { se->conn.capable |= FUSE_CAP_NO_OPEN_SUPPORT; } - if (arg->flags & FUSE_PARALLEL_DIROPS) { + if (flags & FUSE_PARALLEL_DIROPS) { se->conn.capable |= FUSE_CAP_PARALLEL_DIROPS; } - if (arg->flags & FUSE_POSIX_ACL) { + if (flags & FUSE_POSIX_ACL) { se->conn.capable |= FUSE_CAP_POSIX_ACL; } - if (arg->flags & FUSE_HANDLE_KILLPRIV) { + if (flags & FUSE_HANDLE_KILLPRIV) { se->conn.capable |= FUSE_CAP_HANDLE_KILLPRIV; } - if (arg->flags & FUSE_NO_OPENDIR_SUPPORT) { + if (flags & FUSE_NO_OPENDIR_SUPPORT) { se->conn.capable |= FUSE_CAP_NO_OPENDIR_SUPPORT; } - if (!(arg->flags & FUSE_MAX_PAGES)) { + if (!(flags & FUSE_MAX_PAGES)) { size_t max_bufsize = FUSE_DEFAULT_MAX_PAGES_PER_REQ * getpagesize() + FUSE_BUFFER_HEADER_SIZE; if (bufsize > max_bufsize) { bufsize = max_bufsize; } } - if (arg->flags & FUSE_SUBMOUNTS) { + if (flags & FUSE_SUBMOUNTS) { se->conn.capable |= FUSE_CAP_SUBMOUNTS; } - if (arg->flags & FUSE_HANDLE_KILLPRIV_V2) { + if (flags & FUSE_HANDLE_KILLPRIV_V2) { se->conn.capable |= FUSE_CAP_HANDLE_KILLPRIV_V2; } - if (arg->flags & FUSE_SETXATTR_EXT) { + if (flags & FUSE_SETXATTR_EXT) { se->conn.capable |= FUSE_CAP_SETXATTR_EXT; } #ifdef HAVE_SPLICE @@ -2064,7 +2081,7 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, if (se->conn.max_write < bufsize - FUSE_BUFFER_HEADER_SIZE) { se->bufsize = se->conn.max_write + FUSE_BUFFER_HEADER_SIZE; } - if (arg->flags & FUSE_MAX_PAGES) { + if (flags & FUSE_MAX_PAGES) { outarg.flags |= FUSE_MAX_PAGES; outarg.max_pages = (se->conn.max_write - 1) / getpagesize() + 1; }