diff --git a/fs/udf/dir.c b/fs/udf/dir.c index c19dba45aa20..d0f92a52e3ba 100644 --- a/fs/udf/dir.c +++ b/fs/udf/dir.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "udf_i.h" #include "udf_sb.h" @@ -44,7 +45,7 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) struct fileIdentDesc *fi = NULL; struct fileIdentDesc cfi; udf_pblk_t block, iblock; - loff_t nf_pos; + loff_t nf_pos, emit_pos = 0; int flen; unsigned char *fname = NULL, *copy_name = NULL; unsigned char *nameptr; @@ -58,6 +59,7 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) int i, num, ret = 0; struct extent_position epos = { NULL, 0, {0, 0} }; struct super_block *sb = dir->i_sb; + bool pos_valid = false; if (ctx->pos == 0) { if (!dir_emit_dot(file, ctx)) @@ -68,6 +70,21 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) if (nf_pos >= size) goto out; + /* + * Something changed since last readdir (either lseek was called or dir + * changed)? We need to verify the position correctly points at the + * beginning of some dir entry so that the directory parsing code does + * not get confused. Since UDF does not have any reliable way of + * identifying beginning of dir entry (names are under user control), + * we need to scan the directory from the beginning. + */ + if (!inode_eq_iversion(dir, file->f_version)) { + emit_pos = nf_pos; + nf_pos = 0; + } else { + pos_valid = true; + } + fname = kmalloc(UDF_NAME_LEN, GFP_NOFS); if (!fname) { ret = -ENOMEM; @@ -123,13 +140,21 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) while (nf_pos < size) { struct kernel_lb_addr tloc; + loff_t cur_pos = nf_pos; - ctx->pos = (nf_pos >> 2) + 1; + /* Update file position only if we got past the current one */ + if (nf_pos >= emit_pos) { + ctx->pos = (nf_pos >> 2) + 1; + pos_valid = true; + } fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc, &elen, &offset); if (!fi) goto out; + /* Still not at offset where user asked us to read from? */ + if (cur_pos < emit_pos) + continue; liu = le16_to_cpu(cfi.lengthOfImpUse); lfi = cfi.lengthFileIdent; @@ -187,8 +212,11 @@ static int udf_readdir(struct file *file, struct dir_context *ctx) } /* end while */ ctx->pos = (nf_pos >> 2) + 1; + pos_valid = true; out: + if (pos_valid) + file->f_version = inode_query_iversion(dir); if (fibh.sbh != fibh.ebh) brelse(fibh.ebh); brelse(fibh.sbh); diff --git a/fs/udf/namei.c b/fs/udf/namei.c index 3c3d3b20889c..3c009562375d 100644 --- a/fs/udf/namei.c +++ b/fs/udf/namei.c @@ -30,6 +30,7 @@ #include #include #include +#include static inline int udf_match(int len1, const unsigned char *name1, int len2, const unsigned char *name2) @@ -135,6 +136,8 @@ int udf_write_fi(struct inode *inode, struct fileIdentDesc *cfi, mark_buffer_dirty_inode(fibh->ebh, inode); mark_buffer_dirty_inode(fibh->sbh, inode); } + inode_inc_iversion(inode); + return 0; } diff --git a/fs/udf/super.c b/fs/udf/super.c index 5663bae95700..5193b94c0683 100644 --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -57,6 +57,7 @@ #include #include #include +#include #include "udf_sb.h" #include "udf_i.h" @@ -149,6 +150,7 @@ static struct inode *udf_alloc_inode(struct super_block *sb) init_rwsem(&ei->i_data_sem); ei->cached_extent.lstart = -1; spin_lock_init(&ei->i_extent_cache_lock); + inode_set_iversion(&ei->vfs_inode, 1); return &ei->vfs_inode; }