fs/minix: set s_maxbytes correctly

The minix filesystem leaves super_block::s_maxbytes at MAX_NON_LFS rather
than setting it to the actual filesystem-specific limit.  This is broken
because it means userspace doesn't see the standard behavior like getting
EFBIG and SIGXFSZ when exceeding the maximum file size.

Fix this by setting s_maxbytes correctly.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Qiujun Huang <anenbupt@gmail.com>
Link: http://lkml.kernel.org/r/20200628060846.682158-5-ebiggers@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index 0dd9293..7b09a91 100644 (file)
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -150,8 +150,10 @@ static int minix_remount (struct super_block * sb, int * flags, char * data)
        return 0;
 }
 
-static bool minix_check_superblock(struct minix_sb_info *sbi)
+static bool minix_check_superblock(struct super_block *sb)
 {
+       struct minix_sb_info *sbi = minix_sb(sb);
+
        if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
                return false;
 
@@ -161,7 +163,7 @@ static bool minix_check_superblock(struct minix_sb_info *sbi)
         * of indirect blocks which places the limit well above U32_MAX.
         */
        if (sbi->s_version == MINIX_V1 &&
-           sbi->s_max_size > (7 + 512 + 512*512) * BLOCK_SIZE)
+           sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
                return false;
 
        return true;
@@ -202,7 +204,7 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
        sbi->s_zmap_blocks = ms->s_zmap_blocks;
        sbi->s_firstdatazone = ms->s_firstdatazone;
        sbi->s_log_zone_size = ms->s_log_zone_size;
-       sbi->s_max_size = ms->s_max_size;
+       s->s_maxbytes = ms->s_max_size;
        s->s_magic = ms->s_magic;
        if (s->s_magic == MINIX_SUPER_MAGIC) {
                sbi->s_version = MINIX_V1;
@@ -233,7 +235,7 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
                sbi->s_zmap_blocks = m3s->s_zmap_blocks;
                sbi->s_firstdatazone = m3s->s_firstdatazone;
                sbi->s_log_zone_size = m3s->s_log_zone_size;
-               sbi->s_max_size = m3s->s_max_size;
+               s->s_maxbytes = m3s->s_max_size;
                sbi->s_ninodes = m3s->s_ninodes;
                sbi->s_nzones = m3s->s_zones;
                sbi->s_dirsize = 64;
@@ -245,7 +247,7 @@ static int minix_fill_super(struct super_block *s, void *data, int silent)
        } else
                goto out_no_fs;
 
-       if (!minix_check_superblock(sbi))
+       if (!minix_check_superblock(s))
                goto out_illegal_sb;
 
        /*

diff --git a/fs/minix/itree_v1.c b/fs/minix/itree_v1.c
index 046cc96..c0d4182 100644 (file)
--- a/fs/minix/itree_v1.c
+++ b/fs/minix/itree_v1.c
@@ -29,7 +29,7 @@ static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
        if (block < 0) {
                printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
                        block, inode->i_sb->s_bdev);
-       } else if (block >= (minix_sb(inode->i_sb)->s_max_size/BLOCK_SIZE)) {
+       } else if (block >= inode->i_sb->s_maxbytes/BLOCK_SIZE) {
                if (printk_ratelimit())
                        printk("MINIX-fs: block_to_path: "
                               "block %ld too big on dev %pg\n",

diff --git a/fs/minix/itree_v2.c b/fs/minix/itree_v2.c
index f7fc7ec..ee8af2f 100644 (file)
--- a/fs/minix/itree_v2.c
+++ b/fs/minix/itree_v2.c
@@ -32,8 +32,7 @@ static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
        if (block < 0) {
                printk("MINIX-fs: block_to_path: block %ld < 0 on dev %pg\n",
                        block, sb->s_bdev);
-       } else if ((u64)block * (u64)sb->s_blocksize >=
-                       minix_sb(sb)->s_max_size) {
+       } else if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes) {
                if (printk_ratelimit())
                        printk("MINIX-fs: block_to_path: "
                               "block %ld too big on dev %pg\n",

diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index df081e8..168d45d 100644 (file)
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -32,7 +32,6 @@ struct minix_sb_info {
        unsigned long s_zmap_blocks;
        unsigned long s_firstdatazone;
        unsigned long s_log_zone_size;
-       unsigned long s_max_size;
        int s_dirsize;
        int s_namelen;
        struct buffer_head ** s_imap;