Paolo Bonzini <pbonz...@redhat.com> writes:
> Il 28/01/2014 11:55, Kirill A. Shutemov ha scritto:
>> Currently we have few issues with P9_STATS_GEN:
>>
>> - We don't try to read st_gen anything except files or directories, but
>> still set P9_STATS_GEN bit in st_result_mask. It may mislead client:
>> we present garbage as valid st_gen.
>>
>> - If we failed to get valid st_gen with ENOTTY, we ignore error, but
>> still set P9_STATS_GEN bit in st_result_mask.
>>
>> - If we failed to get valid st_gen with any other errno, we fail
>> getattr altogether. It's excessive: we block valid client use-cases,
>> like chdir(2) to non-readable directory with execution bit set.
>>
>> The patch fixes these issues and cleanup code a bit.
>>
>> Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
>> Reviewed-by: Daniel P. Berrange <berra...@redhat.com>
>> Reviewed-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
>> ---
>> hw/9pfs/cofile.c | 4 ----
>> hw/9pfs/virtio-9p-handle.c | 8 +++++++-
>> hw/9pfs/virtio-9p-local.c | 10 ++++++----
>> hw/9pfs/virtio-9p-proxy.c | 3 ++-
>> hw/9pfs/virtio-9p.c | 12 ++++++++++--
>> 5 files changed, 25 insertions(+), 12 deletions(-)
>>
>> diff --git a/hw/9pfs/cofile.c b/hw/9pfs/cofile.c
>> index 194c1306c665..2efebf35710f 100644
>> --- a/hw/9pfs/cofile.c
>> +++ b/hw/9pfs/cofile.c
>> @@ -38,10 +38,6 @@ int v9fs_co_st_gen(V9fsPDU *pdu, V9fsPath *path, mode_t
>> st_mode,
>> });
>> v9fs_path_unlock(s);
>> }
>> - /* The ioctl may not be supported depending on the path */
>> - if (err == -ENOTTY) {
>> - err = 0;
>> - }
>> return err;
>> }
>>
>> diff --git a/hw/9pfs/virtio-9p-handle.c b/hw/9pfs/virtio-9p-handle.c
>> index fe8e0ed19dcc..17002a3d2867 100644
>> --- a/hw/9pfs/virtio-9p-handle.c
>> +++ b/hw/9pfs/virtio-9p-handle.c
>> @@ -582,6 +582,7 @@ static int handle_unlinkat(FsContext *ctx, V9fsPath *dir,
>> static int handle_ioc_getversion(FsContext *ctx, V9fsPath *path,
>> mode_t st_mode, uint64_t *st_gen)
>> {
>> +#ifdef FS_IOC_GETVERSION
>> int err;
>> V9fsFidOpenState fid_open;
>>
>> @@ -590,7 +591,8 @@ static int handle_ioc_getversion(FsContext *ctx,
>> V9fsPath *path,
>> * We can get fd for regular files and directories only
>> */
>> if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
>> - return 0;
>> + errno = ENOTTY;
>> + return -1;
>> }
>> err = handle_open(ctx, path, O_RDONLY, &fid_open);
>> if (err < 0) {
>> @@ -599,6 +601,10 @@ static int handle_ioc_getversion(FsContext *ctx,
>> V9fsPath *path,
>> err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
>> handle_close(ctx, &fid_open);
>> return err;
>> +#else
>> + errno = ENOTTY;
>> + return -1;
>> +#endif
>> }
>>
>> static int handle_init(FsContext *ctx)
>> diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c
>> index fc93e9e6e8da..df0dbffa7ac4 100644
>> --- a/hw/9pfs/virtio-9p-local.c
>> +++ b/hw/9pfs/virtio-9p-local.c
>> @@ -1068,8 +1068,8 @@ err_out:
>> static int local_ioc_getversion(FsContext *ctx, V9fsPath *path,
>> mode_t st_mode, uint64_t *st_gen)
>> {
>> - int err;
>> #ifdef FS_IOC_GETVERSION
>> + int err;
>> V9fsFidOpenState fid_open;
>>
>> /*
>> @@ -1077,7 +1077,8 @@ static int local_ioc_getversion(FsContext *ctx,
>> V9fsPath *path,
>> * We can get fd for regular files and directories only
>> */
>> if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
>> - return 0;
>> + errno = ENOTTY;
>> + return -1;
>> }
>> err = local_open(ctx, path, O_RDONLY, &fid_open);
>> if (err < 0) {
>> @@ -1085,10 +1086,11 @@ static int local_ioc_getversion(FsContext *ctx,
>> V9fsPath *path,
>> }
>> err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
>> local_close(ctx, &fid_open);
>> + return err;
>> #else
>> - err = -ENOTTY;
>> + errno = ENOTTY;
>> + return -1;
>> #endif
>> - return err;
>> }
>>
>> static int local_init(FsContext *ctx)
>> diff --git a/hw/9pfs/virtio-9p-proxy.c b/hw/9pfs/virtio-9p-proxy.c
>> index 5f44bb758b35..b57966d9d883 100644
>> --- a/hw/9pfs/virtio-9p-proxy.c
>> +++ b/hw/9pfs/virtio-9p-proxy.c
>> @@ -1086,7 +1086,8 @@ static int proxy_ioc_getversion(FsContext *fs_ctx,
>> V9fsPath *path,
>> * we can get fd for regular files and directories only
>> */
>> if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
>> - return 0;
>> + errno = ENOTTY;
>> + return -1;
>> }
>> err = v9fs_request(fs_ctx->private, T_GETVERSION, st_gen, "s", path);
>> if (err < 0) {
>> diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c
>> index 8cbb8ae32a03..3e51fcd152f8 100644
>> --- a/hw/9pfs/virtio-9p.c
>> +++ b/hw/9pfs/virtio-9p.c
>> @@ -1080,10 +1080,18 @@ static void v9fs_getattr(void *opaque)
>> /* fill st_gen if requested and supported by underlying fs */
>> if (request_mask & P9_STATS_GEN) {
>> retval = v9fs_co_st_gen(pdu, &fidp->path, stbuf.st_mode,
>> &v9stat_dotl);
>> - if (retval < 0) {
>> + switch (retval) {
>> + case 0:
>> + /* we have valid st_gen: update result mask */
>> + v9stat_dotl.st_result_mask |= P9_STATS_GEN;
>> + break;
>> + case -EINTR:
>> + /* request cancelled */
>> goto out;
>> + default:
>> + /* failed to get st_gen: not fatal, ignore */
>> + break;
>> }
>> - v9stat_dotl.st_result_mask |= P9_STATS_GEN;
>> }
>> retval = pdu_marshal(pdu, offset, "A", &v9stat_dotl);
>> if (retval < 0) {
>>
>
> Michael, are you going to take this patch given that the virtio-9p
> maintainer is AWOL?
I did review the patch, and also specifically asked if we need a pull
request with this just one patch or can it be taken directly to upstream
tree. I was not sure whether generating a pull request with just one
patch was useful.
-aneesh
