From 8de52778798fe39660a8d6b26f290e0c93202761 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 6 Feb 2012 12:45:27 -0500 Subject: vfs: check i_nlink limits in vfs_{mkdir,rename_dir,link} New field of struct super_block - ->s_max_links. Maximal allowed value of ->i_nlink or 0; in the latter case all checks still need to be done in ->link/->mkdir/->rename instances. Note that this limit applies both to directoris and to non-directories. Signed-off-by: Al Viro --- fs/sysv/namei.c | 12 +----------- fs/sysv/super.c | 24 ++++++++++++------------ fs/sysv/sysv.h | 1 - 3 files changed, 13 insertions(+), 24 deletions(-) (limited to 'fs/sysv') diff --git a/fs/sysv/namei.c b/fs/sysv/namei.c index b217797e621b..d7466e293614 100644 --- a/fs/sysv/namei.c +++ b/fs/sysv/namei.c @@ -121,9 +121,6 @@ static int sysv_link(struct dentry * old_dentry, struct inode * dir, { struct inode *inode = old_dentry->d_inode; - if (inode->i_nlink >= SYSV_SB(inode->i_sb)->s_link_max) - return -EMLINK; - inode->i_ctime = CURRENT_TIME_SEC; inode_inc_link_count(inode); ihold(inode); @@ -134,10 +131,8 @@ static int sysv_link(struct dentry * old_dentry, struct inode * dir, static int sysv_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode) { struct inode * inode; - int err = -EMLINK; + int err; - if (dir->i_nlink >= SYSV_SB(dir->i_sb)->s_link_max) - goto out; inode_inc_link_count(dir); inode = sysv_new_inode(dir, S_IFDIR|mode); @@ -251,11 +246,6 @@ static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry, drop_nlink(new_inode); inode_dec_link_count(new_inode); } else { - if (dir_de) { - err = -EMLINK; - if (new_dir->i_nlink >= SYSV_SB(new_dir->i_sb)->s_link_max) - goto out_dir; - } err = sysv_add_link(new_dentry, old_inode); if (err) goto out_dir; diff --git a/fs/sysv/super.c b/fs/sysv/super.c index f60c196913ea..f467740e088c 100644 --- a/fs/sysv/super.c +++ b/fs/sysv/super.c @@ -44,7 +44,7 @@ enum { JAN_1_1980 = (10*365 + 2) * 24 * 60 * 60 }; -static void detected_xenix(struct sysv_sb_info *sbi) +static void detected_xenix(struct sysv_sb_info *sbi, unsigned *max_links) { struct buffer_head *bh1 = sbi->s_bh1; struct buffer_head *bh2 = sbi->s_bh2; @@ -59,7 +59,7 @@ static void detected_xenix(struct sysv_sb_info *sbi) sbd2 = (struct xenix_super_block *) (bh2->b_data - 512); } - sbi->s_link_max = XENIX_LINK_MAX; + *max_links = XENIX_LINK_MAX; sbi->s_fic_size = XENIX_NICINOD; sbi->s_flc_size = XENIX_NICFREE; sbi->s_sbd1 = (char *)sbd1; @@ -75,7 +75,7 @@ static void detected_xenix(struct sysv_sb_info *sbi) sbi->s_nzones = fs32_to_cpu(sbi, sbd1->s_fsize); } -static void detected_sysv4(struct sysv_sb_info *sbi) +static void detected_sysv4(struct sysv_sb_info *sbi, unsigned *max_links) { struct sysv4_super_block * sbd; struct buffer_head *bh1 = sbi->s_bh1; @@ -86,7 +86,7 @@ static void detected_sysv4(struct sysv_sb_info *sbi) else sbd = (struct sysv4_super_block *) bh2->b_data; - sbi->s_link_max = SYSV_LINK_MAX; + *max_links = SYSV_LINK_MAX; sbi->s_fic_size = SYSV_NICINOD; sbi->s_flc_size = SYSV_NICFREE; sbi->s_sbd1 = (char *)sbd; @@ -103,7 +103,7 @@ static void detected_sysv4(struct sysv_sb_info *sbi) sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); } -static void detected_sysv2(struct sysv_sb_info *sbi) +static void detected_sysv2(struct sysv_sb_info *sbi, unsigned *max_links) { struct sysv2_super_block *sbd; struct buffer_head *bh1 = sbi->s_bh1; @@ -114,7 +114,7 @@ static void detected_sysv2(struct sysv_sb_info *sbi) else sbd = (struct sysv2_super_block *) bh2->b_data; - sbi->s_link_max = SYSV_LINK_MAX; + *max_links = SYSV_LINK_MAX; sbi->s_fic_size = SYSV_NICINOD; sbi->s_flc_size = SYSV_NICFREE; sbi->s_sbd1 = (char *)sbd; @@ -131,14 +131,14 @@ static void detected_sysv2(struct sysv_sb_info *sbi) sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); } -static void detected_coherent(struct sysv_sb_info *sbi) +static void detected_coherent(struct sysv_sb_info *sbi, unsigned *max_links) { struct coh_super_block * sbd; struct buffer_head *bh1 = sbi->s_bh1; sbd = (struct coh_super_block *) bh1->b_data; - sbi->s_link_max = COH_LINK_MAX; + *max_links = COH_LINK_MAX; sbi->s_fic_size = COH_NICINOD; sbi->s_flc_size = COH_NICFREE; sbi->s_sbd1 = (char *)sbd; @@ -154,12 +154,12 @@ static void detected_coherent(struct sysv_sb_info *sbi) sbi->s_nzones = fs32_to_cpu(sbi, sbd->s_fsize); } -static void detected_v7(struct sysv_sb_info *sbi) +static void detected_v7(struct sysv_sb_info *sbi, unsigned *max_links) { struct buffer_head *bh2 = sbi->s_bh2; struct v7_super_block *sbd = (struct v7_super_block *)bh2->b_data; - sbi->s_link_max = V7_LINK_MAX; + *max_links = V7_LINK_MAX; sbi->s_fic_size = V7_NICINOD; sbi->s_flc_size = V7_NICFREE; sbi->s_sbd1 = (char *)sbd; @@ -290,7 +290,7 @@ static char *flavour_names[] = { [FSTYPE_AFS] = "AFS", }; -static void (*flavour_setup[])(struct sysv_sb_info *) = { +static void (*flavour_setup[])(struct sysv_sb_info *, unsigned *) = { [FSTYPE_XENIX] = detected_xenix, [FSTYPE_SYSV4] = detected_sysv4, [FSTYPE_SYSV2] = detected_sysv2, @@ -310,7 +310,7 @@ static int complete_read_super(struct super_block *sb, int silent, int size) sbi->s_firstinodezone = 2; - flavour_setup[sbi->s_type](sbi); + flavour_setup[sbi->s_type](sbi, &sb->s_max_links); sbi->s_truncate = 1; sbi->s_ndatazones = sbi->s_nzones - sbi->s_firstdatazone; diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h index 0e4b821c5691..11b07672f6c5 100644 --- a/fs/sysv/sysv.h +++ b/fs/sysv/sysv.h @@ -24,7 +24,6 @@ struct sysv_sb_info { char s_bytesex; /* bytesex (le/be/pdp) */ char s_truncate; /* if 1: names > SYSV_NAMELEN chars are truncated */ /* if 0: they are disallowed (ENAMETOOLONG) */ - nlink_t s_link_max; /* max number of hard links to a file */ unsigned int s_inodes_per_block; /* number of inodes per block */ unsigned int s_inodes_per_block_1; /* inodes_per_block - 1 */ unsigned int s_inodes_per_block_bits; /* log2(inodes_per_block) */ -- cgit v1.2.3-59-g8ed1b