From 64d4ce892383b2ad6d782e080d25502f91bf2a38 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 2 Dec 2019 18:02:12 +0100 Subject: [PATCH 01/10] ext4: fix ext4_empty_dir() for directories with holes Function ext4_empty_dir() doesn't correctly handle directories with holes and crashes on bh->b_data dereference when bh is NULL. Reorganize the loop to use 'offset' variable all the times instead of comparing pointers to current direntry with bh->b_data pointer. Also add more strict checking of '.' and '..' directory entries to avoid entering loop in possibly invalid state on corrupted filesystems. References: CVE-2019-19037 CC: stable@vger.kernel.org Fixes: 4e19d6b65fb4 ("ext4: allow directory holes") Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20191202170213.4761-2-jack@suse.cz Signed-off-by: Theodore Ts'o --- fs/ext4/namei.c | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index a856997d87b5..9e6d14748b5a 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -2822,7 +2822,7 @@ bool ext4_empty_dir(struct inode *inode) { unsigned int offset; struct buffer_head *bh; - struct ext4_dir_entry_2 *de, *de1; + struct ext4_dir_entry_2 *de; struct super_block *sb; if (ext4_has_inline_data(inode)) { @@ -2847,19 +2847,25 @@ bool ext4_empty_dir(struct inode *inode) return true; de = (struct ext4_dir_entry_2 *) bh->b_data; - de1 = ext4_next_entry(de, sb->s_blocksize); - if (le32_to_cpu(de->inode) != inode->i_ino || - le32_to_cpu(de1->inode) == 0 || - strcmp(".", de->name) || strcmp("..", de1->name)) { - ext4_warning_inode(inode, "directory missing '.' and/or '..'"); + if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size, + 0) || + le32_to_cpu(de->inode) != inode->i_ino || strcmp(".", de->name)) { + ext4_warning_inode(inode, "directory missing '.'"); brelse(bh); return true; } - offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + - ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); - de = ext4_next_entry(de1, sb->s_blocksize); + offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); + de = ext4_next_entry(de, sb->s_blocksize); + if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size, + offset) || + le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) { + ext4_warning_inode(inode, "directory missing '..'"); + brelse(bh); + return true; + } + offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); while (offset < inode->i_size) { - if ((void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { + if (!(offset & (sb->s_blocksize - 1))) { unsigned int lblock; brelse(bh); lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); @@ -2870,12 +2876,11 @@ bool ext4_empty_dir(struct inode *inode) } if (IS_ERR(bh)) return true; - de = (struct ext4_dir_entry_2 *) bh->b_data; } + de = (struct ext4_dir_entry_2 *) (bh->b_data + + (offset & (sb->s_blocksize - 1))); if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, bh->b_size, offset)) { - de = (struct ext4_dir_entry_2 *)(bh->b_data + - sb->s_blocksize); offset = (offset | (sb->s_blocksize - 1)) + 1; continue; } @@ -2884,7 +2889,6 @@ bool ext4_empty_dir(struct inode *inode) return false; } offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); - de = ext4_next_entry(de, sb->s_blocksize); } brelse(bh); return true; From 109ba779d6cca2d519c5dd624a3276d03e21948e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 2 Dec 2019 18:02:13 +0100 Subject: [PATCH 02/10] ext4: check for directory entries too close to block end ext4_check_dir_entry() currently does not catch a case when a directory entry ends so close to the block end that the header of the next directory entry would not fit in the remaining space. This can lead to directory iteration code trying to access address beyond end of current buffer head leading to oops. CC: stable@vger.kernel.org Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20191202170213.4761-3-jack@suse.cz Signed-off-by: Theodore Ts'o --- fs/ext4/dir.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index 9fdd2b269d61..6305d5ec25af 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -81,6 +81,11 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, error_msg = "rec_len is too small for name_len"; else if (unlikely(((char *) de - buf) + rlen > size)) error_msg = "directory entry overrun"; + else if (unlikely(((char *) de - buf) + rlen > + size - EXT4_DIR_REC_LEN(1) && + ((char *) de - buf) + rlen != size)) { + error_msg = "directory entry too close to block end"; + } else if (unlikely(le32_to_cpu(de->inode) > le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))) error_msg = "inode out of bounds"; From 707d1a2f601bea6110a5633054253c0cb71b44c1 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sun, 8 Dec 2019 19:43:46 -0500 Subject: [PATCH 03/10] ext4: optimize __ext4_check_dir_entry() Make __ext4_check_dir_entry() a bit easier to understand, and reduce the object size of the function by over 11%. Signed-off-by: Theodore Ts'o Link: https://lore.kernel.org/r/20191209004346.38526-1-tytso@mit.edu Signed-off-by: Theodore Ts'o --- fs/ext4/dir.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index 6305d5ec25af..9f00fc0bf21d 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -72,6 +72,7 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, const char *error_msg = NULL; const int rlen = ext4_rec_len_from_disk(de->rec_len, dir->i_sb->s_blocksize); + const int next_offset = ((char *) de - buf) + rlen; if (unlikely(rlen < EXT4_DIR_REC_LEN(1))) error_msg = "rec_len is smaller than minimal"; @@ -79,13 +80,11 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, error_msg = "rec_len % 4 != 0"; else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len))) error_msg = "rec_len is too small for name_len"; - else if (unlikely(((char *) de - buf) + rlen > size)) + else if (unlikely(next_offset > size)) error_msg = "directory entry overrun"; - else if (unlikely(((char *) de - buf) + rlen > - size - EXT4_DIR_REC_LEN(1) && - ((char *) de - buf) + rlen != size)) { + else if (unlikely(next_offset > size - EXT4_DIR_REC_LEN(1) && + next_offset != size)) error_msg = "directory entry too close to block end"; - } else if (unlikely(le32_to_cpu(de->inode) > le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))) error_msg = "inode out of bounds"; From 7f420d64a08c1dcd65b27be82a27cf2bdb2e7847 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 13 Dec 2019 21:50:11 +0300 Subject: [PATCH 04/10] ext4: unlock on error in ext4_expand_extra_isize() We need to unlock the xattr before returning on this error path. Cc: stable@kernel.org # 4.13 Fixes: c03b45b853f5 ("ext4, project: expand inode extra size if possible") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/20191213185010.6k7yl2tck3wlsdkt@kili.mountain Signed-off-by: Theodore Ts'o --- fs/ext4/inode.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 310e4abd9aca..16e72621e995 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5689,7 +5689,7 @@ int ext4_expand_extra_isize(struct inode *inode, error = ext4_journal_get_write_access(handle, iloc->bh); if (error) { brelse(iloc->bh); - goto out_stop; + goto out_unlock; } error = __ext4_expand_extra_isize(inode, new_extra_isize, iloc, @@ -5699,8 +5699,8 @@ int ext4_expand_extra_isize(struct inode *inode, if (!error) error = rc; +out_unlock: ext4_write_unlock_xattr(inode, &no_expand); -out_stop: ext4_journal_stop(handle); return error; } From a70fd5ac2ea787cafe07b69dadd16b3648ad64ac Mon Sep 17 00:00:00 2001 From: yangerkun Date: Fri, 13 Dec 2019 09:49:00 +0800 Subject: [PATCH 05/10] ext4: reserve revoke credits in __ext4_new_inode It's possible that __ext4_new_inode will release the xattr block, so it will trigger a warning since there is revoke credits will be 0 if the handle == NULL. The below scripts can reproduce it easily. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 3861 at fs/jbd2/revoke.c:374 jbd2_journal_revoke+0x30e/0x540 fs/jbd2/revoke.c:374 ... __ext4_forget+0x1d7/0x800 fs/ext4/ext4_jbd2.c:248 ext4_free_blocks+0x213/0x1d60 fs/ext4/mballoc.c:4743 ext4_xattr_release_block+0x55b/0x780 fs/ext4/xattr.c:1254 ext4_xattr_block_set+0x1c2c/0x2c40 fs/ext4/xattr.c:2112 ext4_xattr_set_handle+0xa7e/0x1090 fs/ext4/xattr.c:2384 __ext4_set_acl+0x54d/0x6c0 fs/ext4/acl.c:214 ext4_init_acl+0x218/0x2e0 fs/ext4/acl.c:293 __ext4_new_inode+0x352a/0x42b0 fs/ext4/ialloc.c:1151 ext4_mkdir+0x2e9/0xbd0 fs/ext4/namei.c:2774 vfs_mkdir+0x386/0x5f0 fs/namei.c:3811 do_mkdirat+0x11c/0x210 fs/namei.c:3834 do_syscall_64+0xa1/0x530 arch/x86/entry/common.c:294 ... ------------------------------------- scripts: mkfs.ext4 /dev/vdb mount /dev/vdb /mnt cd /mnt && mkdir dir && for i in {1..8}; do setfacl -dm "u:user_"$i":rx" dir; done mkdir dir/dir1 && mv dir/dir1 ./ sh repro.sh && add some user [root@localhost ~]# cat repro.sh while [ 1 -eq 1 ]; do rm -rf dir rm -rf dir1/dir1 mkdir dir for i in {1..8}; do setfacl -dm "u:test"$i":rx" dir; done setfacl -m "u:user_9:rx" dir & mkdir dir1/dir1 & done Before exec repro.sh, dir1 has inherit the default acl from dir, and xattr block of dir1 dir is not the same, so the h_refcount of these two dir's xattr block will be 1. Then repro.sh can trigger the warning with the situation show as below. The last h_refcount can be clear with mkdir, and __ext4_new_inode has not reserved revoke credits, so the warning will happened, fix it by reserve revoke credits in __ext4_new_inode. Thread 1 Thread 2 mkdir dir set default acl(will create a xattr block blk1 and the refcount of ext4_xattr_header will be 1) ... mkdir dir1/dir1 ->....->ext4_init_acl ->__ext4_set_acl(set default acl, will reuse blk1, and h_refcount will be 2) setfacl->ext4_set_acl->... ->ext4_xattr_block_set(will create new block blk2 to store xattr) ->__ext4_set_acl(set access acl, since h_refcount of blk1 is 2, will create blk3 to store xattr) ->ext4_xattr_release_block(dec h_refcount of blk1 to 1) ->ext4_xattr_release_block(dec h_refcount and since it is 0, will release the block and trigger the warning) Link: https://lore.kernel.org/r/20191213014900.47228-1-yangerkun@huawei.com Reported-by: Hulk Robot Reviewed-by: Jan Kara Signed-off-by: yangerkun Signed-off-by: Theodore Ts'o --- fs/ext4/ialloc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index dc333e8e51e8..8ca4a23129aa 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -921,8 +921,8 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir, if (!handle) { BUG_ON(nblocks <= 0); handle = __ext4_journal_start_sb(dir->i_sb, line_no, - handle_type, nblocks, - 0, 0); + handle_type, nblocks, 0, + ext4_trans_default_revoke_credits(sb)); if (IS_ERR(handle)) { err = PTR_ERR(handle); ext4_std_error(sb, err); From 9803387c55f7d2ce69aa64340c5fdc6b3027dbc8 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sun, 15 Dec 2019 01:09:03 -0500 Subject: [PATCH 06/10] ext4: validate the debug_want_extra_isize mount option at parse time Instead of setting s_want_extra_size and then making sure that it is a valid value afterwards, validate the field before we set it. This avoids races and other problems when remounting the file system. Link: https://lore.kernel.org/r/20191215063020.GA11512@mit.edu Cc: stable@kernel.org Signed-off-by: Theodore Ts'o Reported-and-tested-by: syzbot+4a39a025912b265cacef@syzkaller.appspotmail.com --- fs/ext4/super.c | 143 +++++++++++++++++++++++------------------------- 1 file changed, 69 insertions(+), 74 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index b205112ca051..46b6d5b150ac 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1886,6 +1886,13 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, } sbi->s_commit_interval = HZ * arg; } else if (token == Opt_debug_want_extra_isize) { + if ((arg & 1) || + (arg < 4) || + (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) { + ext4_msg(sb, KERN_ERR, + "Invalid want_extra_isize %d", arg); + return -1; + } sbi->s_want_extra_isize = arg; } else if (token == Opt_max_batch_time) { sbi->s_max_batch_time = arg; @@ -3540,40 +3547,6 @@ int ext4_calculate_overhead(struct super_block *sb) return 0; } -static void ext4_clamp_want_extra_isize(struct super_block *sb) -{ - struct ext4_sb_info *sbi = EXT4_SB(sb); - struct ext4_super_block *es = sbi->s_es; - unsigned def_extra_isize = sizeof(struct ext4_inode) - - EXT4_GOOD_OLD_INODE_SIZE; - - if (sbi->s_inode_size == EXT4_GOOD_OLD_INODE_SIZE) { - sbi->s_want_extra_isize = 0; - return; - } - if (sbi->s_want_extra_isize < 4) { - sbi->s_want_extra_isize = def_extra_isize; - if (ext4_has_feature_extra_isize(sb)) { - if (sbi->s_want_extra_isize < - le16_to_cpu(es->s_want_extra_isize)) - sbi->s_want_extra_isize = - le16_to_cpu(es->s_want_extra_isize); - if (sbi->s_want_extra_isize < - le16_to_cpu(es->s_min_extra_isize)) - sbi->s_want_extra_isize = - le16_to_cpu(es->s_min_extra_isize); - } - } - /* Check if enough inode space is available */ - if ((sbi->s_want_extra_isize > sbi->s_inode_size) || - (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize > - sbi->s_inode_size)) { - sbi->s_want_extra_isize = def_extra_isize; - ext4_msg(sb, KERN_INFO, - "required extra inode space not available"); - } -} - static void ext4_set_resv_clusters(struct super_block *sb) { ext4_fsblk_t resv_clusters; @@ -3781,6 +3754,68 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) */ sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT; + if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) { + sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE; + sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO; + } else { + sbi->s_inode_size = le16_to_cpu(es->s_inode_size); + sbi->s_first_ino = le32_to_cpu(es->s_first_ino); + if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) { + ext4_msg(sb, KERN_ERR, "invalid first ino: %u", + sbi->s_first_ino); + goto failed_mount; + } + if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) || + (!is_power_of_2(sbi->s_inode_size)) || + (sbi->s_inode_size > blocksize)) { + ext4_msg(sb, KERN_ERR, + "unsupported inode size: %d", + sbi->s_inode_size); + goto failed_mount; + } + /* + * i_atime_extra is the last extra field available for + * [acm]times in struct ext4_inode. Checking for that + * field should suffice to ensure we have extra space + * for all three. + */ + if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) + + sizeof(((struct ext4_inode *)0)->i_atime_extra)) { + sb->s_time_gran = 1; + sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX; + } else { + sb->s_time_gran = NSEC_PER_SEC; + sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX; + } + sb->s_time_min = EXT4_TIMESTAMP_MIN; + } + if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) { + sbi->s_want_extra_isize = sizeof(struct ext4_inode) - + EXT4_GOOD_OLD_INODE_SIZE; + if (ext4_has_feature_extra_isize(sb)) { + unsigned v, max = (sbi->s_inode_size - + EXT4_GOOD_OLD_INODE_SIZE); + + v = le16_to_cpu(es->s_want_extra_isize); + if (v > max) { + ext4_msg(sb, KERN_ERR, + "bad s_want_extra_isize: %d", v); + goto failed_mount; + } + if (sbi->s_want_extra_isize < v) + sbi->s_want_extra_isize = v; + + v = le16_to_cpu(es->s_min_extra_isize); + if (v > max) { + ext4_msg(sb, KERN_ERR, + "bad s_min_extra_isize: %d", v); + goto failed_mount; + } + if (sbi->s_want_extra_isize < v) + sbi->s_want_extra_isize = v; + } + } + if (sbi->s_es->s_mount_opts[0]) { char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts, sizeof(sbi->s_es->s_mount_opts), @@ -4019,42 +4054,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) has_huge_files); sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files); - if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) { - sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE; - sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO; - } else { - sbi->s_inode_size = le16_to_cpu(es->s_inode_size); - sbi->s_first_ino = le32_to_cpu(es->s_first_ino); - if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) { - ext4_msg(sb, KERN_ERR, "invalid first ino: %u", - sbi->s_first_ino); - goto failed_mount; - } - if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) || - (!is_power_of_2(sbi->s_inode_size)) || - (sbi->s_inode_size > blocksize)) { - ext4_msg(sb, KERN_ERR, - "unsupported inode size: %d", - sbi->s_inode_size); - goto failed_mount; - } - /* - * i_atime_extra is the last extra field available for [acm]times in - * struct ext4_inode. Checking for that field should suffice to ensure - * we have extra space for all three. - */ - if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) + - sizeof(((struct ext4_inode *)0)->i_atime_extra)) { - sb->s_time_gran = 1; - sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX; - } else { - sb->s_time_gran = NSEC_PER_SEC; - sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX; - } - - sb->s_time_min = EXT4_TIMESTAMP_MIN; - } - sbi->s_desc_size = le16_to_cpu(es->s_desc_size); if (ext4_has_feature_64bit(sb)) { if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT || @@ -4503,8 +4502,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) } else if (ret) goto failed_mount4a; - ext4_clamp_want_extra_isize(sb); - ext4_set_resv_clusters(sb); err = ext4_setup_system_zone(sb); @@ -5292,8 +5289,6 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) goto restore_opts; } - ext4_clamp_want_extra_isize(sb); - if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^ test_opt(sb, JOURNAL_CHECKSUM)) { ext4_msg(sb, KERN_ERR, "changing journal_checksum " From 69000d82eee1b41d88afc75861153b7e514bb777 Mon Sep 17 00:00:00 2001 From: Phong Tran Date: Fri, 13 Dec 2019 22:33:07 +0700 Subject: [PATCH 07/10] ext4: use RCU API in debug_print_tree struct ext4_sb_info.system_blks was marked __rcu. But access the pointer without using RCU lock and dereference. Sparse warning with __rcu notation: block_validity.c:139:29: warning: incorrect type in argument 1 (different address spaces) block_validity.c:139:29: expected struct rb_root const * block_validity.c:139:29: got struct rb_root [noderef] * Link: https://lore.kernel.org/r/20191213153306.30744-1-tranmanphong@gmail.com Reviewed-by: Jan Kara Signed-off-by: Phong Tran Signed-off-by: Theodore Ts'o --- fs/ext4/block_validity.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/ext4/block_validity.c b/fs/ext4/block_validity.c index d4d4fdfac1a6..1ee04e76bbe0 100644 --- a/fs/ext4/block_validity.c +++ b/fs/ext4/block_validity.c @@ -133,10 +133,13 @@ static void debug_print_tree(struct ext4_sb_info *sbi) { struct rb_node *node; struct ext4_system_zone *entry; + struct ext4_system_blocks *system_blks; int first = 1; printk(KERN_INFO "System zones: "); - node = rb_first(&sbi->system_blks->root); + rcu_read_lock(); + system_blks = rcu_dereference(sbi->system_blks); + node = rb_first(&system_blks->root); while (node) { entry = rb_entry(node, struct ext4_system_zone, node); printk(KERN_CONT "%s%llu-%llu", first ? "" : ", ", @@ -144,6 +147,7 @@ static void debug_print_tree(struct ext4_sb_info *sbi) first = 0; node = rb_next(node); } + rcu_read_unlock(); printk(KERN_CONT "\n"); } From d82d47d5d8a6d40bb622cef31b6c6fa09cbd01ea Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sun, 8 Dec 2019 20:31:32 -0800 Subject: [PATCH 08/10] jbd2: fix kernel-doc notation warning Fix kernel-doc warning by inserting a beginning '*' character for the kernel-doc line. ../include/linux/jbd2.h:461: warning: bad line: journal. These are dirty buffers and revoke descriptor blocks. Link: https://lore.kernel.org/r/53e3ce27-ceae-560d-0fd4-f95728a33e12@infradead.org Cc: stable@kernel.org Signed-off-by: Randy Dunlap Signed-off-by: Theodore Ts'o --- include/linux/jbd2.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 842b62606025..89bf48a81798 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -457,7 +457,7 @@ struct jbd2_revoke_table_s; * @h_journal: Which journal handle belongs to - used iff h_reserved set. * @h_rsv_handle: Handle reserved for finishing the logical operation. * @h_total_credits: Number of remaining buffers we are allowed to add to - journal. These are dirty buffers and revoke descriptor blocks. + * journal. These are dirty buffers and revoke descriptor blocks. * @h_revoke_credits: Number of remaining revoke records available for handle * @h_ref: Reference count on this handle. * @h_err: Field for caller's use to track errors through large fs operations. From 68d7b2d838f1aff4d46a793a2fae33e8ad19223e Mon Sep 17 00:00:00 2001 From: Yunfeng Ye Date: Tue, 17 Dec 2019 22:46:49 +0800 Subject: [PATCH 09/10] ext4: fix unused-but-set-variable warning in ext4_add_entry() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Warning is found when compile with "-Wunused-but-set-variable": fs/ext4/namei.c: In function ‘ext4_add_entry’: fs/ext4/namei.c:2167:23: warning: variable ‘sbi’ set but not used [-Wunused-but-set-variable] struct ext4_sb_info *sbi; ^~~ Fix this by moving the variable @sbi under CONFIG_UNICODE. Signed-off-by: Yunfeng Ye Reviewed-by: Ritesh Harjani Link: https://lore.kernel.org/r/cb5eb904-224a-9701-c38f-cb23514b1fff@huawei.com Signed-off-by: Theodore Ts'o --- fs/ext4/namei.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 9e6d14748b5a..1cb42d940784 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -2164,7 +2164,9 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, struct buffer_head *bh = NULL; struct ext4_dir_entry_2 *de; struct super_block *sb; +#ifdef CONFIG_UNICODE struct ext4_sb_info *sbi; +#endif struct ext4_filename fname; int retval; int dx_fallback=0; @@ -2176,12 +2178,12 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, csum_size = sizeof(struct ext4_dir_entry_tail); sb = dir->i_sb; - sbi = EXT4_SB(sb); blocksize = sb->s_blocksize; if (!dentry->d_name.len) return -EINVAL; #ifdef CONFIG_UNICODE + sbi = EXT4_SB(sb); if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) && sbi->s_encoding && utf8_validate(sbi->s_encoding, &dentry->d_name)) return -EINVAL; From 23f6b02405343103791c6a9533d73716cdf0c672 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 18 Dec 2019 12:12:10 +0100 Subject: [PATCH 10/10] ext4: clarify impact of 'commit' mount option The description of 'commit' mount option dates back to ext3 times. Update the description to match current meaning for ext4. Reported-by: Paul Richards Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20191218111210.14161-1-jack@suse.cz Signed-off-by: Theodore Ts'o --- Documentation/admin-guide/ext4.rst | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/Documentation/admin-guide/ext4.rst b/Documentation/admin-guide/ext4.rst index 059ddcbe769d..9bc93f0ce0c9 100644 --- a/Documentation/admin-guide/ext4.rst +++ b/Documentation/admin-guide/ext4.rst @@ -181,14 +181,17 @@ When mounting an ext4 filesystem, the following option are accepted: system after its metadata has been committed to the journal. commit=nrsec (*) - Ext4 can be told to sync all its data and metadata every 'nrsec' - seconds. The default value is 5 seconds. This means that if you lose - your power, you will lose as much as the latest 5 seconds of work (your - filesystem will not be damaged though, thanks to the journaling). This - default value (or any low value) will hurt performance, but it's good - for data-safety. Setting it to 0 will have the same effect as leaving - it at the default (5 seconds). Setting it to very large values will - improve performance. + This setting limits the maximum age of the running transaction to + 'nrsec' seconds. The default value is 5 seconds. This means that if + you lose your power, you will lose as much as the latest 5 seconds of + metadata changes (your filesystem will not be damaged though, thanks + to the journaling). This default value (or any low value) will hurt + performance, but it's good for data-safety. Setting it to 0 will have + the same effect as leaving it at the default (5 seconds). Setting it + to very large values will improve performance. Note that due to + delayed allocation even older data can be lost on power failure since + writeback of those data begins only after time set in + /proc/sys/vm/dirty_expire_centisecs. barrier=<0|1(*)>, barrier(*), nobarrier This enables/disables the use of write barriers in the jbd code.