From eacdd1606c5170ae7b062f75120deac0e7c6e887 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 12 Oct 2021 10:17:19 +0800 Subject: [PATCH] btrfs-progs: print-tree: fix chunk/block group flags output [BUG] Commit ("btrfs-progs: use raid table for profile names in print-tree.c") introduced one bug in block group and chunk flags output and changed the behavior: item 1 key (FIRST_CHUNK_TREE CHUNK_ITEM 13631488) itemoff 16105 itemsize 80 length 8388608 owner 2 stripe_len 65536 type SINGLE ... item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 22020096) itemoff 15993 itemsize 112 length 8388608 owner 2 stripe_len 65536 type DUP ... item 3 key (FIRST_CHUNK_TREE CHUNK_ITEM 30408704) itemoff 15881 itemsize 112 length 268435456 owner 2 stripe_len 65536 type DUP ... Note that, the flag string only contains the profile (SINGLE/DUP/etc...) no type (DATA/METADATA/SYSTEM). And we have new "SINGLE" string, even that profile has no extra bit to indicate that. [CAUSE] The "SINGLE" part is caused by the raid array which has a name for SINGLE profile, even it doesn't have the corresponding bit. The missing type string is caused by a code bug: strcpy(buf, name); while (*tmp) { *tmp = toupper(*tmp); tmp++; } strcpy(ret, buf); The last strcpy() call overrides the existing string in @ret. [FIX] - Enhance string handling using strn*()/snprintf() - Add extra "UKNOWN.0x%llx" output for unknown profiles - Call proper strncat() to merge type and profile - Add extra handling for "SINGLE" to keep the old output Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- kernel-shared/print-tree.c | 47 +++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 18 deletions(-) diff --git a/kernel-shared/print-tree.c b/kernel-shared/print-tree.c index 67b654e6..39655590 100644 --- a/kernel-shared/print-tree.c +++ b/kernel-shared/print-tree.c @@ -159,40 +159,51 @@ static void print_inode_ref_item(struct extent_buffer *eb, u32 size, } } -/* Caller should ensure sizeof(*ret)>=21 "DATA|METADATA|RAID10" */ +/* The minimal length for the string buffer of block group/chunk flags */ +#define BG_FLAG_STRING_LEN 64 + static void bg_flags_to_str(u64 flags, char *ret) { int empty = 1; + char profile[BG_FLAG_STRING_LEN] = {}; const char *name; + ret[0] = '\0'; if (flags & BTRFS_BLOCK_GROUP_DATA) { empty = 0; - strcpy(ret, "DATA"); + strncpy(ret, "DATA", BG_FLAG_STRING_LEN); } if (flags & BTRFS_BLOCK_GROUP_METADATA) { if (!empty) - strcat(ret, "|"); - strcat(ret, "METADATA"); + strncat(ret, "|", BG_FLAG_STRING_LEN); + strncat(ret, "METADATA", BG_FLAG_STRING_LEN); } if (flags & BTRFS_BLOCK_GROUP_SYSTEM) { if (!empty) - strcat(ret, "|"); - strcat(ret, "SYSTEM"); + strncat(ret, "|", BG_FLAG_STRING_LEN); + strncat(ret, "SYSTEM", BG_FLAG_STRING_LEN); } - strcat(ret, "|"); name = btrfs_bg_type_to_raid_name(flags); if (!name) { - strcat(ret, "UNKNOWN"); + snprintf(profile, BG_FLAG_STRING_LEN, "UNKNOWN.0x%llx", + flags & BTRFS_BLOCK_GROUP_PROFILE_MASK); } else { - char buf[32]; - char *tmp = buf; + int i; - strcpy(buf, name); - while (*tmp) { - *tmp = toupper(*tmp); - tmp++; - } - strcpy(ret, buf); + /* + * Special handing for SINGLE profile, we don't output "SINGLE" + * for SINGLE profile, since there is no such bit for it. + * Thus here we only fill @profile if it's not single. + */ + if (strncmp(name, "single", strlen("single")) != 0) + strncpy(profile, name, BG_FLAG_STRING_LEN); + + for (i = 0; i < BG_FLAG_STRING_LEN && profile[i]; i++) + profile[i] = toupper(profile[i]); + } + if (profile[0]) { + strncat(ret, "|", BG_FLAG_STRING_LEN); + strncat(ret, profile, BG_FLAG_STRING_LEN); } } @@ -215,7 +226,7 @@ void print_chunk_item(struct extent_buffer *eb, struct btrfs_chunk *chunk) u16 num_stripes = btrfs_chunk_num_stripes(eb, chunk); int i; u32 chunk_item_size; - char chunk_flags_str[32] = {0}; + char chunk_flags_str[BG_FLAG_STRING_LEN] = {}; /* The chunk must contain at least one stripe */ if (num_stripes < 1) { @@ -986,7 +997,7 @@ static void print_block_group_item(struct extent_buffer *eb, struct btrfs_block_group_item *bgi) { struct btrfs_block_group_item bg_item; - char flags_str[256]; + char flags_str[BG_FLAG_STRING_LEN] = {}; read_extent_buffer(eb, &bg_item, (unsigned long)bgi, sizeof(bg_item)); memset(flags_str, 0, sizeof(flags_str));