From 4d07bbf2d45683841e578a2f255e4c174534bf38 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:44 -0700 Subject: [PATCH 1/8] tools: ynl-gen: don't declare loop iterator in place The codegen tries to follow the "old" C style and declare loop iterators at the start of the block / function. Only nested request handling breaks this style, so adjust it. Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-2-kuba@kernel.org Signed-off-by: Jakub Kicinski --- tools/net/ynl/pyynl/ynl_gen_c.py | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py index a1427c537030..305f5696bc4f 100755 --- a/tools/net/ynl/pyynl/ynl_gen_c.py +++ b/tools/net/ynl/pyynl/ynl_gen_c.py @@ -654,10 +654,10 @@ class TypeMultiAttr(Type): def attr_put(self, ri, var): if self.attr['type'] in scalars: put_type = self.type - ri.cw.p(f"for (unsigned int i = 0; i < {var}->n_{self.c_name}; i++)") + ri.cw.p(f"for (i = 0; i < {var}->n_{self.c_name}; i++)") ri.cw.p(f"ynl_attr_put_{put_type}(nlh, {self.enum_name}, {var}->{self.c_name}[i]);") elif 'type' not in self.attr or self.attr['type'] == 'nest': - ri.cw.p(f"for (unsigned int i = 0; i < {var}->n_{self.c_name}; i++)") + ri.cw.p(f"for (i = 0; i < {var}->n_{self.c_name}; i++)") self._attr_put_line(ri, var, f"{self.nested_render_name}_put(nlh, " + f"{self.enum_name}, &{var}->{self.c_name}[i])") else: @@ -1644,11 +1644,23 @@ def put_req_nested_prototype(ri, struct, suffix=';'): def put_req_nested(ri, struct): + local_vars = [] + init_lines = [] + + local_vars.append('struct nlattr *nest;') + init_lines.append("nest = ynl_attr_nest_start(nlh, attr_type);") + + for _, arg in struct.member_list(): + if arg.presence_type() == 'count': + local_vars.append('unsigned int i;') + break + put_req_nested_prototype(ri, struct, suffix='') ri.cw.block_start() - ri.cw.write_func_lvar('struct nlattr *nest;') + ri.cw.write_func_lvar(local_vars) - ri.cw.p("nest = ynl_attr_nest_start(nlh, attr_type);") + for line in init_lines: + ri.cw.p(line) for _, arg in struct.member_list(): arg.attr_put(ri, "obj") @@ -1850,6 +1862,11 @@ def print_req(ri): local_vars += ['size_t hdr_len;', 'void *hdr;'] + for _, attr in ri.struct["request"].member_list(): + if attr.presence_type() == 'count': + local_vars += ['unsigned int i;'] + break + print_prototype(ri, direction, terminate=False) ri.cw.block_start() ri.cw.write_func_lvar(local_vars) From dfa464b4a603984d648a9beb9bce72df5858c1e2 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:45 -0700 Subject: [PATCH 2/8] tools: ynl-gen: move local vars after the opening bracket The "function writing helper" tries to put local variables between prototype and the opening bracket. Clearly wrong, but up until now nothing actually uses it to write local vars so it wasn't noticed. Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-3-kuba@kernel.org Signed-off-by: Jakub Kicinski --- tools/net/ynl/pyynl/ynl_gen_c.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py index 305f5696bc4f..662a925bd9e1 100755 --- a/tools/net/ynl/pyynl/ynl_gen_c.py +++ b/tools/net/ynl/pyynl/ynl_gen_c.py @@ -1399,9 +1399,9 @@ class CodeWriter: def write_func(self, qual_ret, name, body, args=None, local_vars=None): self.write_func_prot(qual_ret=qual_ret, name=name, args=args) + self.block_start() self.write_func_lvar(local_vars=local_vars) - self.block_start() for line in body: self.p(line) self.block_end() From ce6cb8113c842b94e77364b247c4f85c7b34e0c2 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:46 -0700 Subject: [PATCH 3/8] tools: ynl-gen: individually free previous values on double set When user calls request_attrA_set() multiple times (for the same attribute), and attrA is of type which allocates memory - we try to free the previously associated values. For array types (including multi-attr) we have only freed the array, but the array may have contained pointers. Refactor the code generation for free attr and reuse the generated lines in setters to flush out the previous state. Since setters are static inlines in the header we need to add forward declarations for the free helpers of pure nested structs. Track which types get used by arrays and include the right forwad declarations. At least ethtool string set and bit set would not be freed without this. Tho, admittedly, overriding already set attribute twice is likely a very very rare thing to do. Fixes: be5bea1cc0bf ("net: add basic C code generators for Netlink") Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-4-kuba@kernel.org Signed-off-by: Jakub Kicinski --- tools/net/ynl/pyynl/ynl_gen_c.py | 62 +++++++++++++++++++++++--------- 1 file changed, 45 insertions(+), 17 deletions(-) diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py index 662a925bd9e1..2d856ccc88f4 100755 --- a/tools/net/ynl/pyynl/ynl_gen_c.py +++ b/tools/net/ynl/pyynl/ynl_gen_c.py @@ -162,9 +162,15 @@ class Type(SpecAttr): def free_needs_iter(self): return False - def free(self, ri, var, ref): + def _free_lines(self, ri, var, ref): if self.is_multi_val() or self.presence_type() == 'len': - ri.cw.p(f'free({var}->{ref}{self.c_name});') + return [f'free({var}->{ref}{self.c_name});'] + return [] + + def free(self, ri, var, ref): + lines = self._free_lines(ri, var, ref) + for line in lines: + ri.cw.p(line) def arg_member(self, ri): member = self._complex_member_type(ri) @@ -263,6 +269,10 @@ class Type(SpecAttr): var = "req" member = f"{var}->{'.'.join(ref)}" + local_vars = [] + if self.free_needs_iter(): + local_vars += ['unsigned int i;'] + code = [] presence = '' for i in range(0, len(ref)): @@ -272,6 +282,10 @@ class Type(SpecAttr): if i == len(ref) - 1 and self.presence_type() != 'bit': continue code.append(presence + ' = 1;') + ref_path = '.'.join(ref[:-1]) + if ref_path: + ref_path += '.' + code += self._free_lines(ri, var, ref_path) code += self._setter_lines(ri, member, presence) func_name = f"{op_prefix(ri, direction, deref=deref)}_set_{'_'.join(ref)}" @@ -279,7 +293,8 @@ class Type(SpecAttr): alloc = bool([x for x in code if 'alloc(' in x]) if free and not alloc: func_name = '__' + func_name - ri.cw.write_func('static inline void', func_name, body=code, + ri.cw.write_func('static inline void', func_name, local_vars=local_vars, + body=code, args=[f'{type_name(ri, direction, deref=deref)} *{var}'] + self.arg_member(ri)) @@ -482,8 +497,7 @@ class TypeString(Type): ['unsigned int len;'] def _setter_lines(self, ri, member, presence): - return [f"free({member});", - f"{presence}_len = strlen({self.c_name});", + return [f"{presence}_len = strlen({self.c_name});", f"{member} = malloc({presence}_len + 1);", f'memcpy({member}, {self.c_name}, {presence}_len);', f'{member}[{presence}_len] = 0;'] @@ -536,8 +550,7 @@ class TypeBinary(Type): ['unsigned int len;'] def _setter_lines(self, ri, member, presence): - return [f"free({member});", - f"{presence}_len = len;", + return [f"{presence}_len = len;", f"{member} = malloc({presence}_len);", f'memcpy({member}, {self.c_name}, {presence}_len);'] @@ -574,12 +587,14 @@ class TypeNest(Type): def _complex_member_type(self, ri): return self.nested_struct_type - def free(self, ri, var, ref): + def _free_lines(self, ri, var, ref): + lines = [] at = '&' if self.is_recursive_for_op(ri): at = '' - ri.cw.p(f'if ({var}->{ref}{self.c_name})') - ri.cw.p(f'{self.nested_render_name}_free({at}{var}->{ref}{self.c_name});') + lines += [f'if ({var}->{ref}{self.c_name})'] + lines += [f'{self.nested_render_name}_free({at}{var}->{ref}{self.c_name});'] + return lines def _attr_typol(self): return f'.type = YNL_PT_NEST, .nest = &{self.nested_render_name}_nest, ' @@ -632,15 +647,19 @@ class TypeMultiAttr(Type): def free_needs_iter(self): return 'type' not in self.attr or self.attr['type'] == 'nest' - def free(self, ri, var, ref): + def _free_lines(self, ri, var, ref): + lines = [] if self.attr['type'] in scalars: - ri.cw.p(f"free({var}->{ref}{self.c_name});") + lines += [f"free({var}->{ref}{self.c_name});"] elif 'type' not in self.attr or self.attr['type'] == 'nest': - ri.cw.p(f"for (i = 0; i < {var}->{ref}n_{self.c_name}; i++)") - ri.cw.p(f'{self.nested_render_name}_free(&{var}->{ref}{self.c_name}[i]);') - ri.cw.p(f"free({var}->{ref}{self.c_name});") + lines += [ + f"for (i = 0; i < {var}->{ref}n_{self.c_name}; i++)", + f'{self.nested_render_name}_free(&{var}->{ref}{self.c_name}[i]);', + f"free({var}->{ref}{self.c_name});", + ] else: raise Exception(f"Free of MultiAttr sub-type {self.attr['type']} not supported yet") + return lines def _attr_policy(self, policy): return self.base_type._attr_policy(policy) @@ -666,8 +685,7 @@ class TypeMultiAttr(Type): def _setter_lines(self, ri, member, presence): # For multi-attr we have a count, not presence, hack up the presence presence = presence[:-(len('_present.') + len(self.c_name))] + "n_" + self.c_name - return [f"free({member});", - f"{member} = {self.c_name};", + return [f"{member} = {self.c_name};", f"{presence} = n_{self.c_name};"] @@ -755,6 +773,7 @@ class Struct: self.request = False self.reply = False self.recursive = False + self.in_multi_val = False # used by a MultiAttr or and legacy arrays self.attr_list = [] self.attrs = dict() @@ -1122,6 +1141,10 @@ class Family(SpecFamily): if attr in rs_members['reply']: self.pure_nested_structs[nested].reply = True + if spec.is_multi_val(): + child = self.pure_nested_structs.get(nested) + child.in_multi_val = True + self._sort_pure_types() # Propagate the request / reply / recursive @@ -1136,6 +1159,8 @@ class Family(SpecFamily): struct.child_nests.update(child.child_nests) child.request |= struct.request child.reply |= struct.reply + if spec.is_multi_val(): + child.in_multi_val = True if attr_set in struct.child_nests: struct.recursive = True @@ -2958,6 +2983,9 @@ def main(): for attr_set, struct in parsed.pure_nested_structs.items(): ri = RenderInfo(cw, parsed, args.mode, "", "", attr_set) print_type_full(ri, struct) + if struct.request and struct.in_multi_val: + free_rsp_nested_prototype(ri) + cw.nl() for op_name, op in parsed.ops.items(): cw.p(f"/* ============== {op.enum_name} ============== */") From 57e7dedf2b8c72caa6f04b9e08b19e4f370562fa Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:47 -0700 Subject: [PATCH 4/8] tools: ynl-gen: make sure we validate subtype of array-nest ArrayNest AKA indexed-array support currently skips inner type validation. We count the attributes and then we parse them, make sure we call validate, too. Otherwise buggy / unexpected kernel response may lead to crashes. Fixes: be5bea1cc0bf ("net: add basic C code generators for Netlink") Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-5-kuba@kernel.org Signed-off-by: Jakub Kicinski --- tools/net/ynl/pyynl/ynl_gen_c.py | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py index 2d856ccc88f4..30c0a34b2784 100755 --- a/tools/net/ynl/pyynl/ynl_gen_c.py +++ b/tools/net/ynl/pyynl/ynl_gen_c.py @@ -714,8 +714,11 @@ class TypeArrayNest(Type): def _attr_get(self, ri, var): local_vars = ['const struct nlattr *attr2;'] get_lines = [f'attr_{self.c_name} = attr;', - 'ynl_attr_for_each_nested(attr2, attr)', - f'\t{var}->n_{self.c_name}++;'] + 'ynl_attr_for_each_nested(attr2, attr) {', + '\tif (ynl_attr_validate(yarg, attr2))', + '\t\treturn YNL_PARSE_CB_ERROR;', + f'\t{var}->n_{self.c_name}++;', + '}'] return get_lines, None, local_vars From acf4da17deada7f8b120e051aa6c9cac40dbd83b Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:48 -0700 Subject: [PATCH 5/8] netlink: specs: rt-link: add an attr layer around alt-ifname alt-ifname attr is directly placed in requests (as an alternative to ifname) but in responses its wrapped up in IFLA_PROP_LIST and only there is may be multi-attr. See rtnl_fill_prop_list(). Fixes: b2f63d904e72 ("doc/netlink: Add spec for rt link messages") Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-6-kuba@kernel.org Signed-off-by: Jakub Kicinski --- Documentation/netlink/specs/rt_link.yaml | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/Documentation/netlink/specs/rt_link.yaml b/Documentation/netlink/specs/rt_link.yaml index 31238455f8e9..200e9a7e5b11 100644 --- a/Documentation/netlink/specs/rt_link.yaml +++ b/Documentation/netlink/specs/rt_link.yaml @@ -1113,11 +1113,10 @@ attribute-sets: - name: prop-list type: nest - nested-attributes: link-attrs + nested-attributes: prop-list-link-attrs - name: alt-ifname type: string - multi-attr: true - name: perm-address type: binary @@ -1163,6 +1162,13 @@ attribute-sets: - name: netns-immutable type: u8 + - + name: prop-list-link-attrs + subset-of: link-attrs + attributes: + - + name: alt-ifname + multi-attr: true - name: af-spec-attrs attributes: @@ -2453,7 +2459,6 @@ operations: - min-mtu - max-mtu - prop-list - - alt-ifname - perm-address - proto-down-reason - parent-dev-name From 540201c0ef7e8e7b169f68a238ade931a81a31a6 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:49 -0700 Subject: [PATCH 6/8] netlink: specs: rtnetlink: attribute naming corrections Some attribute names diverge in very minor ways from the C names. These are most likely typos, and they prevent the C codegen from working. Fixes: bc515ed06652 ("netlink: specs: Add a spec for neighbor tables in rtnetlink") Fixes: b2f63d904e72 ("doc/netlink: Add spec for rt link messages") Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-7-kuba@kernel.org Signed-off-by: Jakub Kicinski --- Documentation/netlink/specs/rt_link.yaml | 6 +++--- Documentation/netlink/specs/rt_neigh.yaml | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/Documentation/netlink/specs/rt_link.yaml b/Documentation/netlink/specs/rt_link.yaml index 200e9a7e5b11..03323d7f58dc 100644 --- a/Documentation/netlink/specs/rt_link.yaml +++ b/Documentation/netlink/specs/rt_link.yaml @@ -1591,7 +1591,7 @@ attribute-sets: name: nf-call-iptables type: u8 - - name: nf-call-ip6-tables + name: nf-call-ip6tables type: u8 - name: nf-call-arptables @@ -2083,7 +2083,7 @@ attribute-sets: name: id type: u16 - - name: flag + name: flags type: binary struct: ifla-vlan-flags - @@ -2171,7 +2171,7 @@ attribute-sets: type: binary struct: ifla-cacheinfo - - name: icmp6-stats + name: icmp6stats type: binary struct: ifla-icmp6-stats - diff --git a/Documentation/netlink/specs/rt_neigh.yaml b/Documentation/netlink/specs/rt_neigh.yaml index e670b6dc07be..a1e137a16abd 100644 --- a/Documentation/netlink/specs/rt_neigh.yaml +++ b/Documentation/netlink/specs/rt_neigh.yaml @@ -189,7 +189,7 @@ attribute-sets: type: binary display-hint: ipv4 - - name: lladr + name: lladdr type: binary display-hint: mac - From beb3c5ad8829b52057f48a776a9d9558b98c157f Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:50 -0700 Subject: [PATCH 7/8] netlink: specs: rt-link: adjust mctp attribute naming MCTP attribute naming is inconsistent. In C we have: IFLA_MCTP_NET, IFLA_MCTP_PHYS_BINDING, ^^^^ but in YAML: - mctp-net - phys-binding ^ no "mctp" It's unclear whether the "mctp" part of the name is supposed to be a prefix or part of attribute name. Make it a prefix, seems cleaner, even tho technically phys-binding was added later. Fixes: b2f63d904e72 ("doc/netlink: Add spec for rt link messages") Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-8-kuba@kernel.org Signed-off-by: Jakub Kicinski --- Documentation/netlink/specs/rt_link.yaml | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Documentation/netlink/specs/rt_link.yaml b/Documentation/netlink/specs/rt_link.yaml index 03323d7f58dc..6b9d5ee87d93 100644 --- a/Documentation/netlink/specs/rt_link.yaml +++ b/Documentation/netlink/specs/rt_link.yaml @@ -2185,9 +2185,10 @@ attribute-sets: type: u32 - name: mctp-attrs + name-prefix: ifla-mctp- attributes: - - name: mctp-net + name: net type: u32 - name: phys-binding From e31f86ee4b9ccb844baf2131da8e5d4d6f23aa1d Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 14 Apr 2025 14:18:51 -0700 Subject: [PATCH 8/8] netlink: specs: rt-neigh: prefix struct nfmsg members with ndm Attach ndm- to all members of struct nfmsg. We could possibly use name-prefix just for C, but I don't think we have any precedent for using name-prefix on structs, and other rtnetlink sub-specs give full names for fixed header struct members. Fixes: bc515ed06652 ("netlink: specs: Add a spec for neighbor tables in rtnetlink") Reviewed-by: Donald Hunter Reviewed-by: Jacob Keller Link: https://patch.msgid.link/20250414211851.602096-9-kuba@kernel.org Signed-off-by: Jakub Kicinski --- Documentation/netlink/specs/rt_neigh.yaml | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/Documentation/netlink/specs/rt_neigh.yaml b/Documentation/netlink/specs/rt_neigh.yaml index a1e137a16abd..a843caa72259 100644 --- a/Documentation/netlink/specs/rt_neigh.yaml +++ b/Documentation/netlink/specs/rt_neigh.yaml @@ -13,25 +13,25 @@ definitions: type: struct members: - - name: family + name: ndm-family type: u8 - - name: pad + name: ndm-pad type: pad len: 3 - - name: ifindex + name: ndm-ifindex type: s32 - - name: state + name: ndm-state type: u16 enum: nud-state - - name: flags + name: ndm-flags type: u8 enum: ntf-flags - - name: type + name: ndm-type type: u8 enum: rtm-type -