From 94dfc73e7cf4a31da66b8843f0b9283ddd6b8381 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Wed, 6 Apr 2022 19:36:51 -0500 Subject: treewide: uapi: Replace zero-length arrays with flexible-array members MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. This code was transformed with the help of Coccinelle: (linux-5.19-rc2$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch) @@ identifier S, member, array; type T1, T2; @@ struct S { ... T1 member; T2 array[ - 0 ]; }; -fstrict-flex-arrays=3 is coming and we need to land these changes to prevent issues like these in the short future: ../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0, but the source string has length 2 (including NUL byte) [-Wfortify-source] strcpy(de3->name, "."); ^ Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If this breaks anything, we can use a union with a new member name. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays Link: https://github.com/KSPP/linux/issues/78 Build-tested-by: kernel test robot Link: https://lore.kernel.org/lkml/62b675ec.wKX6AOZ6cbE71vtF%25lkp@intel.com/ Acked-by: Dan Williams # For ndctl.h Signed-off-by: Gustavo A. R. Silva --- tools/include/uapi/drm/i915_drm.h | 6 +++--- tools/include/uapi/linux/fs.h | 2 +- tools/include/uapi/linux/if_tun.h | 2 +- tools/include/uapi/linux/kvm.h | 8 ++++---- tools/include/uapi/linux/perf_event.h | 2 +- tools/include/uapi/linux/pkt_cls.h | 4 ++-- tools/include/uapi/linux/seg6.h | 4 ++-- tools/include/uapi/linux/usbdevice_fs.h | 4 ++-- tools/include/uapi/sound/asound.h | 2 +- 9 files changed, 17 insertions(+), 17 deletions(-) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/drm/i915_drm.h b/tools/include/uapi/drm/i915_drm.h index 05c3642aaece..239b91b13c60 100644 --- a/tools/include/uapi/drm/i915_drm.h +++ b/tools/include/uapi/drm/i915_drm.h @@ -2060,7 +2060,7 @@ struct i915_context_engines_load_balance { __u64 mbz64; /* reserved for future use; must be zero */ - struct i915_engine_class_instance engines[0]; + struct i915_engine_class_instance engines[]; } __attribute__((packed)); #define I915_DEFINE_CONTEXT_ENGINES_LOAD_BALANCE(name__, N__) struct { \ @@ -2098,7 +2098,7 @@ struct i915_context_engines_bond { __u64 flags; /* all undefined flags must be zero */ __u64 mbz64[4]; /* reserved for future use; must be zero */ - struct i915_engine_class_instance engines[0]; + struct i915_engine_class_instance engines[]; } __attribute__((packed)); #define I915_DEFINE_CONTEXT_ENGINES_BOND(name__, N__) struct { \ @@ -2225,7 +2225,7 @@ struct i915_context_engines_parallel_submit { * length = width (i) * num_siblings (j) * index = j + i * num_siblings */ - struct i915_engine_class_instance engines[0]; + struct i915_engine_class_instance engines[]; } __packed; diff --git a/tools/include/uapi/linux/fs.h b/tools/include/uapi/linux/fs.h index bdf7b404b3e7..b7b56871029c 100644 --- a/tools/include/uapi/linux/fs.h +++ b/tools/include/uapi/linux/fs.h @@ -90,7 +90,7 @@ struct file_dedupe_range { __u16 dest_count; /* in - total elements in info array */ __u16 reserved1; /* must be zero */ __u32 reserved2; /* must be zero */ - struct file_dedupe_range_info info[0]; + struct file_dedupe_range_info info[]; }; /* And dynamically-tunable limits and defaults: */ diff --git a/tools/include/uapi/linux/if_tun.h b/tools/include/uapi/linux/if_tun.h index 454ae31b93c7..2ec07de1d73b 100644 --- a/tools/include/uapi/linux/if_tun.h +++ b/tools/include/uapi/linux/if_tun.h @@ -108,7 +108,7 @@ struct tun_pi { struct tun_filter { __u16 flags; /* TUN_FLT_ flags see above */ __u16 count; /* Number of addresses */ - __u8 addr[0][ETH_ALEN]; + __u8 addr[][ETH_ALEN]; }; #endif /* _UAPI__IF_TUN_H */ diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h index 6a184d260c7f..37ce8cbac322 100644 --- a/tools/include/uapi/linux/kvm.h +++ b/tools/include/uapi/linux/kvm.h @@ -539,7 +539,7 @@ struct kvm_coalesced_mmio { struct kvm_coalesced_mmio_ring { __u32 first, last; - struct kvm_coalesced_mmio coalesced_mmio[0]; + struct kvm_coalesced_mmio coalesced_mmio[]; }; #define KVM_COALESCED_MMIO_MAX \ @@ -618,7 +618,7 @@ struct kvm_clear_dirty_log { /* for KVM_SET_SIGNAL_MASK */ struct kvm_signal_mask { __u32 len; - __u8 sigset[0]; + __u8 sigset[]; }; /* for KVM_TPR_ACCESS_REPORTING */ @@ -1216,7 +1216,7 @@ struct kvm_irq_routing_entry { struct kvm_irq_routing { __u32 nr; __u32 flags; - struct kvm_irq_routing_entry entries[0]; + struct kvm_irq_routing_entry entries[]; }; #endif @@ -1335,7 +1335,7 @@ struct kvm_dirty_tlb { struct kvm_reg_list { __u64 n; /* number of regs */ - __u64 reg[0]; + __u64 reg[]; }; struct kvm_one_reg { diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h index d37629dbad72..4653834f078f 100644 --- a/tools/include/uapi/linux/perf_event.h +++ b/tools/include/uapi/linux/perf_event.h @@ -491,7 +491,7 @@ struct perf_event_query_bpf { /* * User provided buffer to store program ids */ - __u32 ids[0]; + __u32 ids[]; }; /* diff --git a/tools/include/uapi/linux/pkt_cls.h b/tools/include/uapi/linux/pkt_cls.h index 12153771396a..3faee0199a9b 100644 --- a/tools/include/uapi/linux/pkt_cls.h +++ b/tools/include/uapi/linux/pkt_cls.h @@ -180,7 +180,7 @@ struct tc_u32_sel { short hoff; __be32 hmask; - struct tc_u32_key keys[0]; + struct tc_u32_key keys[]; }; struct tc_u32_mark { @@ -192,7 +192,7 @@ struct tc_u32_mark { struct tc_u32_pcnt { __u64 rcnt; __u64 rhit; - __u64 kcnts[0]; + __u64 kcnts[]; }; /* Flags */ diff --git a/tools/include/uapi/linux/seg6.h b/tools/include/uapi/linux/seg6.h index 286e8d6a8e98..f94baf154c47 100644 --- a/tools/include/uapi/linux/seg6.h +++ b/tools/include/uapi/linux/seg6.h @@ -30,7 +30,7 @@ struct ipv6_sr_hdr { __u8 flags; __u16 tag; - struct in6_addr segments[0]; + struct in6_addr segments[]; }; #define SR6_FLAG1_PROTECTED (1 << 6) @@ -49,7 +49,7 @@ struct ipv6_sr_hdr { struct sr6_tlv { __u8 type; __u8 len; - __u8 data[0]; + __u8 data[]; }; #endif diff --git a/tools/include/uapi/linux/usbdevice_fs.h b/tools/include/uapi/linux/usbdevice_fs.h index cf525cddeb94..74a84e02422a 100644 --- a/tools/include/uapi/linux/usbdevice_fs.h +++ b/tools/include/uapi/linux/usbdevice_fs.h @@ -131,7 +131,7 @@ struct usbdevfs_urb { unsigned int signr; /* signal to be sent on completion, or 0 if none should be sent. */ void __user *usercontext; - struct usbdevfs_iso_packet_desc iso_frame_desc[0]; + struct usbdevfs_iso_packet_desc iso_frame_desc[]; }; /* ioctls for talking directly to drivers */ @@ -176,7 +176,7 @@ struct usbdevfs_disconnect_claim { struct usbdevfs_streams { unsigned int num_streams; /* Not used by USBDEVFS_FREE_STREAMS */ unsigned int num_eps; - unsigned char eps[0]; + unsigned char eps[]; }; /* diff --git a/tools/include/uapi/sound/asound.h b/tools/include/uapi/sound/asound.h index 2d3e5df39a59..3974a2a911cc 100644 --- a/tools/include/uapi/sound/asound.h +++ b/tools/include/uapi/sound/asound.h @@ -1106,7 +1106,7 @@ struct snd_ctl_elem_value { struct snd_ctl_tlv { unsigned int numid; /* control element numeric identification */ unsigned int length; /* in bytes aligned to 4 */ - unsigned int tlv[0]; /* first TLV */ + unsigned int tlv[]; /* first TLV */ }; #define SNDRV_CTL_IOCTL_PVERSION _IOR('U', 0x00, int) -- cgit v1.2.3