| Message ID | 172343558582.6062.9756574878881138559@noble.neil.brown.name (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | SQUASH: nfsd: move error choice for incorrect object types to version-specific code. | expand |
On Mon, 2024-08-12 at 14:06 +1000, NeilBrown wrote: > > [This should be squashed into the existing patch for the same name, > with this commit message used instead of the current one. It addresses > the pynfs failures that Jeff found] > > If an NFS operation expects a particular sort of object (file, dir, link, > etc) but gets a file handle for a different sort of object, it must > return an error. The actual error varies among NFS version in non-trivial > ways. > > For v2 and v3 there are ISDIR and NOTDIR errors and, for NFSv4 only, > INVAL is suitable. > > For v4.0 there is also NFS4ERR_SYMLINK which should be used if a SYMLINK > was found when not expected. This take precedence over NOTDIR. > > For v4.1+ there is also NFS4ERR_WRONG_TYPE which should be used in > preference to EINVAL when none of the specific error codes apply. > > When nfsd_mode_check() finds a symlink where it expected a directory it > needs to return an error code that can be converted to NOTDIR for v2 or > v3 but will be SYMLINK for v4. It must be different from the error > code returns when it finds a symlink but expects a regular file - that > must be converted to EINVAL or SYMLINK. > > So we introduce an internal error code nfserr_symlink_not_dir which each > version converts as appropriate. > > nfsd_check_obj_isreg() is similar to nfsd_mode_check() except that it is > only used by NFSv4 and only for OPEN. NFSERR_INVAL is never a suitable > error if the object is the wrong time. For v4.0 we use nfserr_symlink > for non-dirs even if not a symlink. For v4.1 we have nfserr_wrong_type. > To handle this difference we introduce an internal status code > nfserr_wrong_type_open. > > As a result of these changes, nfsd_mode_check() doesn't need an rqstp > arg any more. > > Note that NFSv4 operations are actually performed in the xdr code(!!!) > so to the only place that we can map the status code successfully is in > nfsd4_encode_operation(). > > Signed-off-by: NeilBrown <neilb@suse.de> > --- > fs/nfsd/nfs4proc.c | 21 +-------------------- > fs/nfsd/nfs4xdr.c | 26 ++++++++++++++++++++++++++ > fs/nfsd/nfsd.h | 6 ++++++ > 3 files changed, 33 insertions(+), 20 deletions(-) > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > index 2e355085e443..e010d627d545 100644 > --- a/fs/nfsd/nfs4proc.c > +++ b/fs/nfsd/nfs4proc.c > @@ -168,7 +168,7 @@ static __be32 nfsd_check_obj_isreg(struct svc_fh *fh) > return nfserr_isdir; > if (S_ISLNK(mode)) > return nfserr_symlink; > - return nfserr_wrong_type; > + return nfserr_wrong_type_open; > } > > static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate, struct nfsd4_open *open, struct svc_fh *resfh) > @@ -179,23 +179,6 @@ static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate > &resfh->fh_handle); > } > > -static __be32 nfsd4_map_status(__be32 status, u32 minor) > -{ > - switch (status) { > - case nfs_ok: > - break; > - case nfserr_wrong_type: > - /* RFC 8881 - 15.1.2.9 */ > - if (minor == 0) > - status = nfserr_inval; > - break; > - case nfserr_symlink_not_dir: > - status = nfserr_symlink; > - break; > - } > - return status; > -} > - > static inline bool nfsd4_create_is_exclusive(int createmode) > { > return createmode == NFS4_CREATE_EXCLUSIVE || > @@ -2815,8 +2798,6 @@ nfsd4_proc_compound(struct svc_rqst *rqstp) > nfsd4_encode_replay(resp->xdr, op); > status = op->status = op->replay->rp_status; > } else { > - op->status = nfsd4_map_status(op->status, > - cstate->minorversion); > nfsd4_encode_operation(resp, op); > status = op->status; > } > diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c > index 42b41d55d4ed..a0c1fc19aea4 100644 > --- a/fs/nfsd/nfs4xdr.c > +++ b/fs/nfsd/nfs4xdr.c > @@ -5729,6 +5729,30 @@ __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize) > return nfserr_rep_too_big; > } > > +static __be32 nfsd4_map_status(__be32 status, u32 minor) > +{ > + switch (status) { > + case nfs_ok: > + break; > + case nfserr_wrong_type: > + /* RFC 8881 - 15.1.2.9 */ > + if (minor == 0) > + status = nfserr_inval; > + break; > + case nfserr_wrong_type_open: > + /* RFC 7530 - 16.16.6 */ > + if (minor == 0) > + status = nfserr_symlink; > + else > + status = nfserr_wrong_type; > + break; > + case nfserr_symlink_not_dir: > + status = nfserr_symlink; > + break; > + } > + return status; > +} > + > void > nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) > { > @@ -5796,6 +5820,8 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) > so->so_replay.rp_buf, len); > } > status: > + op->status = nfsd4_map_status(op->status, > + resp->cstate.minorversion); > *p = op->status; > release: > if (opdesc && opdesc->op_release) > diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > index 4ccbf014a2c7..b4503e698ffd 100644 > --- a/fs/nfsd/nfsd.h > +++ b/fs/nfsd/nfsd.h > @@ -359,6 +359,12 @@ enum { > */ > NFSERR_SYMLINK_NOT_DIR, > #define nfserr_symlink_not_dir cpu_to_be32(NFSERR_SYMLINK_NOT_DIR) > + > +/* non-{reg,dir,symlink} found by open - handled differently > + * in v4.0 than v4.1. > + */ > + NFSERR_WRONG_TYPE_OPEN, > +#define nfserr_wrong_type_open cpu_to_be32(NFSERR_WRONG_TYPE_OPEN) > }; > > /* Check for dir entries '.' and '..' */ Much better! I ran it through pynfs and everything passed. Reviewed-by: Jeff Layton <jlayton@kernel.org>
On Mon, Aug 12, 2024 at 02:06:25PM +1000, NeilBrown wrote: > > [This should be squashed into the existing patch for the same name, > with this commit message used instead of the current one. It addresses > the pynfs failures that Jeff found] > > If an NFS operation expects a particular sort of object (file, dir, link, > etc) but gets a file handle for a different sort of object, it must > return an error. The actual error varies among NFS version in non-trivial > ways. > > For v2 and v3 there are ISDIR and NOTDIR errors and, for NFSv4 only, > INVAL is suitable. > > For v4.0 there is also NFS4ERR_SYMLINK which should be used if a SYMLINK > was found when not expected. This take precedence over NOTDIR. > > For v4.1+ there is also NFS4ERR_WRONG_TYPE which should be used in > preference to EINVAL when none of the specific error codes apply. > > When nfsd_mode_check() finds a symlink where it expected a directory it > needs to return an error code that can be converted to NOTDIR for v2 or > v3 but will be SYMLINK for v4. It must be different from the error > code returns when it finds a symlink but expects a regular file - that > must be converted to EINVAL or SYMLINK. > > So we introduce an internal error code nfserr_symlink_not_dir which each > version converts as appropriate. > > nfsd_check_obj_isreg() is similar to nfsd_mode_check() except that it is > only used by NFSv4 and only for OPEN. NFSERR_INVAL is never a suitable > error if the object is the wrong time. For v4.0 we use nfserr_symlink > for non-dirs even if not a symlink. For v4.1 we have nfserr_wrong_type. > To handle this difference we introduce an internal status code > nfserr_wrong_type_open. > > As a result of these changes, nfsd_mode_check() doesn't need an rqstp > arg any more. > > Note that NFSv4 operations are actually performed in the xdr code(!!!) > so to the only place that we can map the status code successfully is in > nfsd4_encode_operation(). Thanks for noting the RFC sections in the comments, that will be very helpful for us forgetful old farts. nfsd_check_obj_isreg's only caller is do_open_lookup, and the minor version number is available there, via nfsd4_compound_state. If the minor version is passed to nfsd_check_obj_isreg, it can correctly choose to return nfserr_symlink or nfserr_wrong_type, yes? That would eliminate the need for nfserr_wrong_type_open, perhaps. What were the other error code leaks you found? > Signed-off-by: NeilBrown <neilb@suse.de> > --- > fs/nfsd/nfs4proc.c | 21 +-------------------- > fs/nfsd/nfs4xdr.c | 26 ++++++++++++++++++++++++++ > fs/nfsd/nfsd.h | 6 ++++++ > 3 files changed, 33 insertions(+), 20 deletions(-) > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > index 2e355085e443..e010d627d545 100644 > --- a/fs/nfsd/nfs4proc.c > +++ b/fs/nfsd/nfs4proc.c > @@ -168,7 +168,7 @@ static __be32 nfsd_check_obj_isreg(struct svc_fh *fh) > return nfserr_isdir; > if (S_ISLNK(mode)) > return nfserr_symlink; > - return nfserr_wrong_type; > + return nfserr_wrong_type_open; > } > > static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate, struct nfsd4_open *open, struct svc_fh *resfh) > @@ -179,23 +179,6 @@ static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate > &resfh->fh_handle); > } > > -static __be32 nfsd4_map_status(__be32 status, u32 minor) > -{ > - switch (status) { > - case nfs_ok: > - break; > - case nfserr_wrong_type: > - /* RFC 8881 - 15.1.2.9 */ > - if (minor == 0) > - status = nfserr_inval; > - break; > - case nfserr_symlink_not_dir: > - status = nfserr_symlink; > - break; > - } > - return status; > -} > - > static inline bool nfsd4_create_is_exclusive(int createmode) > { > return createmode == NFS4_CREATE_EXCLUSIVE || > @@ -2815,8 +2798,6 @@ nfsd4_proc_compound(struct svc_rqst *rqstp) > nfsd4_encode_replay(resp->xdr, op); > status = op->status = op->replay->rp_status; > } else { > - op->status = nfsd4_map_status(op->status, > - cstate->minorversion); > nfsd4_encode_operation(resp, op); > status = op->status; > } > diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c > index 42b41d55d4ed..a0c1fc19aea4 100644 > --- a/fs/nfsd/nfs4xdr.c > +++ b/fs/nfsd/nfs4xdr.c > @@ -5729,6 +5729,30 @@ __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize) > return nfserr_rep_too_big; > } > > +static __be32 nfsd4_map_status(__be32 status, u32 minor) > +{ > + switch (status) { > + case nfs_ok: > + break; > + case nfserr_wrong_type: > + /* RFC 8881 - 15.1.2.9 */ > + if (minor == 0) > + status = nfserr_inval; > + break; > + case nfserr_wrong_type_open: > + /* RFC 7530 - 16.16.6 */ > + if (minor == 0) > + status = nfserr_symlink; > + else > + status = nfserr_wrong_type; > + break; > + case nfserr_symlink_not_dir: > + status = nfserr_symlink; > + break; > + } > + return status; > +} > + > void > nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) > { > @@ -5796,6 +5820,8 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) > so->so_replay.rp_buf, len); > } > status: > + op->status = nfsd4_map_status(op->status, > + resp->cstate.minorversion); > *p = op->status; > release: > if (opdesc && opdesc->op_release) > diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > index 4ccbf014a2c7..b4503e698ffd 100644 > --- a/fs/nfsd/nfsd.h > +++ b/fs/nfsd/nfsd.h > @@ -359,6 +359,12 @@ enum { > */ > NFSERR_SYMLINK_NOT_DIR, > #define nfserr_symlink_not_dir cpu_to_be32(NFSERR_SYMLINK_NOT_DIR) > + > +/* non-{reg,dir,symlink} found by open - handled differently > + * in v4.0 than v4.1. > + */ > + NFSERR_WRONG_TYPE_OPEN, > +#define nfserr_wrong_type_open cpu_to_be32(NFSERR_WRONG_TYPE_OPEN) > }; > > /* Check for dir entries '.' and '..' */ > -- > 2.44.0 >
On Tue, 13 Aug 2024, Chuck Lever wrote: > On Mon, Aug 12, 2024 at 02:06:25PM +1000, NeilBrown wrote: > > > > [This should be squashed into the existing patch for the same name, > > with this commit message used instead of the current one. It addresses > > the pynfs failures that Jeff found] > > > > If an NFS operation expects a particular sort of object (file, dir, link, > > etc) but gets a file handle for a different sort of object, it must > > return an error. The actual error varies among NFS version in non-trivial > > ways. > > > > For v2 and v3 there are ISDIR and NOTDIR errors and, for NFSv4 only, > > INVAL is suitable. > > > > For v4.0 there is also NFS4ERR_SYMLINK which should be used if a SYMLINK > > was found when not expected. This take precedence over NOTDIR. > > > > For v4.1+ there is also NFS4ERR_WRONG_TYPE which should be used in > > preference to EINVAL when none of the specific error codes apply. > > > > When nfsd_mode_check() finds a symlink where it expected a directory it > > needs to return an error code that can be converted to NOTDIR for v2 or > > v3 but will be SYMLINK for v4. It must be different from the error > > code returns when it finds a symlink but expects a regular file - that > > must be converted to EINVAL or SYMLINK. > > > > So we introduce an internal error code nfserr_symlink_not_dir which each > > version converts as appropriate. > > > > nfsd_check_obj_isreg() is similar to nfsd_mode_check() except that it is > > only used by NFSv4 and only for OPEN. NFSERR_INVAL is never a suitable > > error if the object is the wrong time. For v4.0 we use nfserr_symlink > > for non-dirs even if not a symlink. For v4.1 we have nfserr_wrong_type. > > To handle this difference we introduce an internal status code > > nfserr_wrong_type_open. > > > > As a result of these changes, nfsd_mode_check() doesn't need an rqstp > > arg any more. > > > > Note that NFSv4 operations are actually performed in the xdr code(!!!) > > so to the only place that we can map the status code successfully is in > > nfsd4_encode_operation(). > > Thanks for noting the RFC sections in the comments, that will be > very helpful for us forgetful old farts. > > nfsd_check_obj_isreg's only caller is do_open_lookup, and the minor > version number is available there, via nfsd4_compound_state. If the > minor version is passed to nfsd_check_obj_isreg, it can correctly > choose to return nfserr_symlink or nfserr_wrong_type, yes? That > would eliminate the need for nfserr_wrong_type_open, perhaps. Probably a good idea. The original goal of this series was to reduce the number of checks on version number by moving version-specific choices to version-specific code. However that doesn't apply to differences between 4.0 and 4.1 as we don't have distinct code for the distinct minor versions. I'll post an alternate SQUASH patch. > > What were the other error code leaks you found? They were happening because I was calling nfsd4_map_status() before nfsd4_encode_operation(). This is *before* the status in set in many cases. status is often set inside the xdr encode functions called by nfsd4_encode_operation(). Moving the call to nfsd4_map_status() inside that function fixed those leaks. NeilBrown
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 2e355085e443..e010d627d545 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -168,7 +168,7 @@ static __be32 nfsd_check_obj_isreg(struct svc_fh *fh) return nfserr_isdir; if (S_ISLNK(mode)) return nfserr_symlink; - return nfserr_wrong_type; + return nfserr_wrong_type_open; } static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate, struct nfsd4_open *open, struct svc_fh *resfh) @@ -179,23 +179,6 @@ static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate &resfh->fh_handle); } -static __be32 nfsd4_map_status(__be32 status, u32 minor) -{ - switch (status) { - case nfs_ok: - break; - case nfserr_wrong_type: - /* RFC 8881 - 15.1.2.9 */ - if (minor == 0) - status = nfserr_inval; - break; - case nfserr_symlink_not_dir: - status = nfserr_symlink; - break; - } - return status; -} - static inline bool nfsd4_create_is_exclusive(int createmode) { return createmode == NFS4_CREATE_EXCLUSIVE || @@ -2815,8 +2798,6 @@ nfsd4_proc_compound(struct svc_rqst *rqstp) nfsd4_encode_replay(resp->xdr, op); status = op->status = op->replay->rp_status; } else { - op->status = nfsd4_map_status(op->status, - cstate->minorversion); nfsd4_encode_operation(resp, op); status = op->status; } diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 42b41d55d4ed..a0c1fc19aea4 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -5729,6 +5729,30 @@ __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize) return nfserr_rep_too_big; } +static __be32 nfsd4_map_status(__be32 status, u32 minor) +{ + switch (status) { + case nfs_ok: + break; + case nfserr_wrong_type: + /* RFC 8881 - 15.1.2.9 */ + if (minor == 0) + status = nfserr_inval; + break; + case nfserr_wrong_type_open: + /* RFC 7530 - 16.16.6 */ + if (minor == 0) + status = nfserr_symlink; + else + status = nfserr_wrong_type; + break; + case nfserr_symlink_not_dir: + status = nfserr_symlink; + break; + } + return status; +} + void nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) { @@ -5796,6 +5820,8 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) so->so_replay.rp_buf, len); } status: + op->status = nfsd4_map_status(op->status, + resp->cstate.minorversion); *p = op->status; release: if (opdesc && opdesc->op_release) diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 4ccbf014a2c7..b4503e698ffd 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -359,6 +359,12 @@ enum { */ NFSERR_SYMLINK_NOT_DIR, #define nfserr_symlink_not_dir cpu_to_be32(NFSERR_SYMLINK_NOT_DIR) + +/* non-{reg,dir,symlink} found by open - handled differently + * in v4.0 than v4.1. + */ + NFSERR_WRONG_TYPE_OPEN, +#define nfserr_wrong_type_open cpu_to_be32(NFSERR_WRONG_TYPE_OPEN) }; /* Check for dir entries '.' and '..' */
[This should be squashed into the existing patch for the same name, with this commit message used instead of the current one. It addresses the pynfs failures that Jeff found] If an NFS operation expects a particular sort of object (file, dir, link, etc) but gets a file handle for a different sort of object, it must return an error. The actual error varies among NFS version in non-trivial ways. For v2 and v3 there are ISDIR and NOTDIR errors and, for NFSv4 only, INVAL is suitable. For v4.0 there is also NFS4ERR_SYMLINK which should be used if a SYMLINK was found when not expected. This take precedence over NOTDIR. For v4.1+ there is also NFS4ERR_WRONG_TYPE which should be used in preference to EINVAL when none of the specific error codes apply. When nfsd_mode_check() finds a symlink where it expected a directory it needs to return an error code that can be converted to NOTDIR for v2 or v3 but will be SYMLINK for v4. It must be different from the error code returns when it finds a symlink but expects a regular file - that must be converted to EINVAL or SYMLINK. So we introduce an internal error code nfserr_symlink_not_dir which each version converts as appropriate. nfsd_check_obj_isreg() is similar to nfsd_mode_check() except that it is only used by NFSv4 and only for OPEN. NFSERR_INVAL is never a suitable error if the object is the wrong time. For v4.0 we use nfserr_symlink for non-dirs even if not a symlink. For v4.1 we have nfserr_wrong_type. To handle this difference we introduce an internal status code nfserr_wrong_type_open. As a result of these changes, nfsd_mode_check() doesn't need an rqstp arg any more. Note that NFSv4 operations are actually performed in the xdr code(!!!) so to the only place that we can map the status code successfully is in nfsd4_encode_operation(). Signed-off-by: NeilBrown <neilb@suse.de> --- fs/nfsd/nfs4proc.c | 21 +-------------------- fs/nfsd/nfs4xdr.c | 26 ++++++++++++++++++++++++++ fs/nfsd/nfsd.h | 6 ++++++ 3 files changed, 33 insertions(+), 20 deletions(-)