2007-05-02 09:13:26

by Kalpak Shah

[permalink] [raw]
Subject: [PATCH] e2fsprogs: Additions in EA checking

Hi,

This patch makes the following changes to EA checking:

1) Allow in-inode EAs to have a hash.
2) Connect zero-length inodes that have an EA to lost+found.
3) Addition of hash function for EAs

Signed-off-by: Andreas Dilger <[email protected]>
Signed-off-by: Kalpak Shah <[email protected]>

Index: e2fsprogs-1.40/e2fsck/e2fsck.h
===================================================================
--- e2fsprogs-1.40.orig/e2fsck/e2fsck.h
+++ e2fsprogs-1.40/e2fsck/e2fsck.h
@@ -475,6 +475,9 @@ extern void init_resource_track(struct r
extern int inode_has_valid_blocks(struct ext2_inode *inode);
extern void e2fsck_read_inode(e2fsck_t ctx, unsigned long ino,
struct ext2_inode * inode, const char * proc);
+extern void e2fsck_read_inode_full(e2fsck_t ctx, unsigned long ino,
+ struct ext2_inode *inode,
+ const int bufsize, const char *proc);
extern void e2fsck_write_inode(e2fsck_t ctx, unsigned long ino,
struct ext2_inode * inode, const char * proc);
extern void e2fsck_write_inode_full(e2fsck_t ctx, unsigned long ino,
Index: e2fsprogs-1.40/e2fsck/pass1.c
===================================================================
--- e2fsprogs-1.40.orig/e2fsck/pass1.c
+++ e2fsprogs-1.40/e2fsck/pass1.c
@@ -250,8 +250,8 @@ static void check_ea_in_inode(e2fsck_t c
int problem = 0;

inode = (struct ext2_inode_large *) pctx->inode;
- storage_size = EXT2_INODE_SIZE(ctx->fs->super) - EXT2_GOOD_OLD_INODE_SIZE -
- inode->i_extra_isize;
+ storage_size = EXT2_INODE_SIZE(ctx->fs->super) -
+ EXT2_GOOD_OLD_INODE_SIZE - inode->i_extra_isize;
start = ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
inode->i_extra_isize + sizeof(__u32);
end = (char *) inode + EXT2_INODE_SIZE(ctx->fs->super);
@@ -263,6 +263,7 @@ static void check_ea_in_inode(e2fsck_t c
remain = storage_size - sizeof(__u32);

while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
+ __u32 hash;

/* header eats this space */
remain -= sizeof(struct ext2_ext_attr_entry);
@@ -291,8 +292,11 @@ static void check_ea_in_inode(e2fsck_t c
goto fix;
}

- /* e_hash must be 0 in inode's ea */
- if (entry->e_hash != 0) {
+ hash = ext2fs_ext_attr_hash_entry(entry,
+ start + entry->e_value_offs);
+
+ /* e_hash may be 0 in older inode's ea */
+ if (entry->e_hash != 0 && entry->e_hash != hash) {
pctx->num = entry->e_hash;
problem = PR_1_ATTR_HASH;
goto fix;
@@ -307,9 +311,6 @@ fix:
* it seems like a corruption. it's very unlikely we could repair
* EA(s) in automatic fashion -bzzz
*/
-#if 0
- problem = PR_1_ATTR_HASH;
-#endif
if (problem == 0 || !fix_problem(ctx, problem, pctx))
return;

@@ -1357,10 +1358,13 @@ static int check_ext_attr(e2fsck_t ctx,
entry = (struct ext2_ext_attr_entry *)(header+1);
end = block_buf + fs->blocksize;
while ((char *)entry < end && *(__u32 *)entry) {
+ __u32 hash;
+
if (region_allocate(region, (char *)entry - (char *)header,
EXT2_EXT_ATTR_LEN(entry->e_name_len))) {
if (fix_problem(ctx, PR_1_EA_ALLOC_COLLISION, pctx))
goto clear_extattr;
+ break;
}
if ((ctx->ext_attr_ver == 1 &&
(entry->e_name_len == 0 || entry->e_name_index != 0)) ||
@@ -1368,6 +1372,7 @@ static int check_ext_attr(e2fsck_t ctx,
entry->e_name_index == 0)) {
if (fix_problem(ctx, PR_1_EA_BAD_NAME, pctx))
goto clear_extattr;
+ break;
}
if (entry->e_value_block != 0) {
if (fix_problem(ctx, PR_1_EA_BAD_VALUE, pctx))
@@ -1379,6 +1384,17 @@ static int check_ext_attr(e2fsck_t ctx,
if (fix_problem(ctx, PR_1_EA_ALLOC_COLLISION, pctx))
goto clear_extattr;
}
+
+ hash = ext2fs_ext_attr_hash_entry(entry, block_buf +
+ entry->e_value_offs);
+
+ if (entry->e_hash != hash) {
+ pctx->num = entry->e_hash;
+ if (fix_problem(ctx, PR_1_ATTR_HASH, pctx))
+ goto clear_extattr;
+ entry->e_hash = hash;
+ }
+
entry = EXT2_EXT_ATTR_NEXT(entry);
}
if (region_allocate(region, (char *)entry - (char *)header, 4)) {
@@ -1500,8 +1516,11 @@ static void check_blocks(e2fsck_t ctx, s
}
}

- if (inode->i_file_acl && check_ext_attr(ctx, pctx, block_buf))
+ if (inode->i_file_acl && check_ext_attr(ctx, pctx, block_buf)) {
+ if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
+ goto out;
pb.num_blocks++;
+ }

if (ext2fs_inode_has_valid_blocks(inode))
pctx->errcode = ext2fs_block_iterate2(fs, ino,
Index: e2fsprogs-1.40/e2fsck/pass4.c
===================================================================
--- e2fsprogs-1.40.orig/e2fsck/pass4.c
+++ e2fsprogs-1.40/e2fsck/pass4.c
@@ -15,6 +15,7 @@

#include "e2fsck.h"
#include "problem.h"
+#include <ext2fs/ext2_ext_attr.h>

/*
* This routine is called when an inode is not connected to the
@@ -23,31 +24,41 @@
* This subroutine returns 1 then the caller shouldn't bother with the
* rest of the pass 4 tests.
*/
-static int disconnect_inode(e2fsck_t ctx, ext2_ino_t i)
+static int disconnect_inode(e2fsck_t ctx, ext2_ino_t i,
+ struct ext2_inode *inode)
{
ext2_filsys fs = ctx->fs;
- struct ext2_inode inode;
struct problem_context pctx;
+ __u32 eamagic = 0;
+ int extra_size = 0;

- e2fsck_read_inode(ctx, i, &inode, "pass4: disconnect_inode");
+ if (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE) {
+ e2fsck_read_inode_full(ctx, i, inode,EXT2_INODE_SIZE(fs->super),
+ "pass4: disconnect_inode");
+ extra_size = ((struct ext2_inode_large *)inode)->i_extra_isize;
+ } else {
+ e2fsck_read_inode(ctx, i, inode, "pass4: disconnect_inode");
+ }
clear_problem_context(&pctx);
pctx.ino = i;
- pctx.inode = &inode;
+ pctx.inode = inode;

+ if (EXT2_INODE_SIZE(fs->super) -EXT2_GOOD_OLD_INODE_SIZE -extra_size >0)
+ eamagic = *(__u32 *)(((char *)inode) +EXT2_GOOD_OLD_INODE_SIZE +
+ extra_size);
/*
* Offer to delete any zero-length files that does not have
* blocks. If there is an EA block, it might have useful
* information, so we won't prompt to delete it, but let it be
* reconnected to lost+found.
*/
- if (!inode.i_blocks && (LINUX_S_ISREG(inode.i_mode) ||
- LINUX_S_ISDIR(inode.i_mode))) {
+ if (!inode->i_blocks && eamagic != EXT2_EXT_ATTR_MAGIC &&
+ (LINUX_S_ISREG(inode->i_mode) || LINUX_S_ISDIR(inode->i_mode))) {
if (fix_problem(ctx, PR_4_ZERO_LEN_INODE, &pctx)) {
ext2fs_icount_store(ctx->inode_link_info, i, 0);
- inode.i_links_count = 0;
- inode.i_dtime = ctx->now;
- e2fsck_write_inode(ctx, i, &inode,
- "disconnect_inode");
+ inode->i_links_count = 0;
+ inode->i_dtime = ctx->now;
+ e2fsck_write_inode(ctx, i, inode, "disconnect_inode");
/*
* Fix up the bitmaps...
*/
@@ -55,7 +66,7 @@ static int disconnect_inode(e2fsck_t ctx
ext2fs_unmark_inode_bitmap(ctx->inode_used_map, i);
ext2fs_unmark_inode_bitmap(ctx->inode_dir_map, i);
ext2fs_inode_alloc_stats2(fs, i, -1,
- LINUX_S_ISDIR(inode.i_mode));
+ LINUX_S_ISDIR(inode->i_mode));
return 0;
}
}
@@ -83,7 +94,7 @@ void e2fsck_pass4(e2fsck_t ctx)
{
ext2_filsys fs = ctx->fs;
ext2_ino_t i;
- struct ext2_inode inode;
+ struct ext2_inode *inode;
#ifdef RESOURCE_TRACK
struct resource_track rtrack;
#endif
@@ -111,6 +122,9 @@ void e2fsck_pass4(e2fsck_t ctx)
if ((ctx->progress)(ctx, 4, 0, maxgroup))
return;

+ inode = e2fsck_allocate_memory(ctx, EXT2_INODE_SIZE(fs->super),
+ "scratch inode");
+
/* Protect loop from wrap-around if s_inodes_count maxed */
for (i=1; i <= fs->super->s_inodes_count && i > 0; i++) {
if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
@@ -138,7 +152,7 @@ void e2fsck_pass4(e2fsck_t ctx)
fs->blocksize, "bad_inode buffer");
if (e2fsck_process_bad_inode(ctx, 0, i, buf))
continue;
- if (disconnect_inode(ctx, i))
+ if (disconnect_inode(ctx, i, inode))
continue;
ext2fs_icount_fetch(ctx->inode_link_info, i,
&link_count);
@@ -146,18 +160,18 @@ void e2fsck_pass4(e2fsck_t ctx)
&link_counted);
}
if (link_counted != link_count) {
- e2fsck_read_inode(ctx, i, &inode, "pass4");
+ e2fsck_read_inode(ctx, i, inode, "pass4");
pctx.ino = i;
- pctx.inode = &inode;
- if (link_count != inode.i_links_count) {
+ pctx.inode = inode;
+ if (link_count != inode->i_links_count) {
pctx.num = link_count;
fix_problem(ctx,
PR_4_INCONSISTENT_COUNT, &pctx);
}
pctx.num = link_counted;
if (fix_problem(ctx, PR_4_BAD_REF_COUNT, &pctx)) {
- inode.i_links_count = link_counted;
- e2fsck_write_inode(ctx, i, &inode, "pass4");
+ inode->i_links_count = link_counted;
+ e2fsck_write_inode(ctx, i, inode, "pass4");
}
}
}
@@ -170,6 +184,8 @@ void e2fsck_pass4(e2fsck_t ctx)
errout:
if (buf)
ext2fs_free_mem(&buf);
+
+ ext2fs_free_mem(&inode);
#ifdef RESOURCE_TRACK
if (ctx->options & E2F_OPT_TIME2) {
e2fsck_clear_progbar(ctx);
Index: e2fsprogs-1.40/e2fsck/util.c
===================================================================
--- e2fsprogs-1.40.orig/e2fsck/util.c
+++ e2fsprogs-1.40/e2fsck/util.c
@@ -361,6 +361,20 @@ void e2fsck_read_inode(e2fsck_t ctx, uns
}
}

+void e2fsck_read_inode_full(e2fsck_t ctx, unsigned long ino,
+ struct ext2_inode *inode, int bufsize,
+ const char *proc)
+{
+ int retval;
+
+ retval = ext2fs_read_inode_full(ctx->fs, ino, inode, bufsize);
+ if (retval) {
+ com_err("ext2fs_read_inode_full", retval,
+ _("while reading inode %ld in %s"), ino, proc);
+ fatal_error(ctx, 0);
+ }
+}
+
extern void e2fsck_write_inode_full(e2fsck_t ctx, unsigned long ino,
struct ext2_inode * inode, int bufsize,
const char *proc)
Index: e2fsprogs-1.40/lib/ext2fs/ext2_ext_attr.h
===================================================================
--- e2fsprogs-1.40.orig/lib/ext2fs/ext2_ext_attr.h
+++ e2fsprogs-1.40/lib/ext2fs/ext2_ext_attr.h
@@ -30,7 +30,7 @@ struct ext2_ext_attr_entry {
__u32 e_value_block; /* disk block attribute is stored on (n/i) */
__u32 e_value_size; /* size of attribute value */
__u32 e_hash; /* hash value of name and value */
-#if 0
+#if 1
char e_name[0]; /* attribute name */
#endif
};
Index: e2fsprogs-1.40/lib/ext2fs/ext2fs.h
===================================================================
--- e2fsprogs-1.40.orig/lib/ext2fs/ext2fs.h
+++ e2fsprogs-1.40/lib/ext2fs/ext2fs.h
@@ -83,10 +83,12 @@ typedef __u32 ext2_dirhash_t;
#include "com_err.h"
#include "ext2_io.h"
#include "ext2_err.h"
+#include "ext2_ext_attr.h"
#else
#include <et/com_err.h>
#include <ext2fs/ext2_io.h>
#include <ext2fs/ext2_err.h>
+#include <ext2fs/ext2_ext_attr.h>
#endif

/*
@@ -714,6 +716,8 @@ extern errcode_t ext2fs_dup_handle(ext2_
extern errcode_t ext2fs_expand_dir(ext2_filsys fs, ext2_ino_t dir);

/* ext_attr.c */
+extern __u32 ext2fs_ext_attr_hash_entry(struct ext2_ext_attr_entry *entry,
+ void *data);
extern errcode_t ext2fs_read_ext_attr(ext2_filsys fs, blk_t block, void *buf);
extern errcode_t ext2fs_write_ext_attr(ext2_filsys fs, blk_t block,
void *buf);
Index: e2fsprogs-1.40/lib/ext2fs/ext_attr.c
===================================================================
--- e2fsprogs-1.40.orig/lib/ext2fs/ext_attr.c
+++ e2fsprogs-1.40/lib/ext2fs/ext_attr.c
@@ -23,6 +23,42 @@

#include "ext2fs.h"

+#define NAME_HASH_SHIFT 5
+#define VALUE_HASH_SHIFT 16
+
+/*
+ * ext2_xattr_hash_entry()
+ *
+ * Compute the hash of an extended attribute.
+ */
+__u32 ext2fs_ext_attr_hash_entry(struct ext2_ext_attr_entry *entry, void *data)
+{
+ __u32 hash = 0;
+ char *name = entry->e_name;
+ int n;
+
+ for (n = 0; n < entry->e_name_len; n++) {
+ hash = (hash << NAME_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
+ *name++;
+ }
+
+ if (entry->e_value_block == 0 && entry->e_value_size != 0) {
+ __u32 *value = (__u32 *)data;
+ for (n = (entry->e_value_size + EXT2_EXT_ATTR_ROUND) >>
+ EXT2_EXT_ATTR_PAD_BITS; n; n--) {
+ hash = (hash << VALUE_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
+ *value++;
+ }
+ }
+
+ return hash;
+}
+
+#undef NAME_HASH_SHIFT
+#undef VALUE_HASH_SHIFT
+
errcode_t ext2fs_read_ext_attr(ext2_filsys fs, blk_t block, void *buf)
{
errcode_t retval;
Index: e2fsprogs-1.40/lib/ext2fs/swapfs.c
===================================================================
--- e2fsprogs-1.40.orig/lib/ext2fs/swapfs.c
+++ e2fsprogs-1.40/lib/ext2fs/swapfs.c
@@ -110,6 +110,7 @@ void ext2fs_swap_ext_attr(char *to, char
to_header->h_magic = ext2fs_swab32(from_header->h_magic);
to_header->h_blocks = ext2fs_swab32(from_header->h_blocks);
to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
+ to_header->h_hash = ext2fs_swab32(from_header->h_hash);
for (n=0; n<4; n++)
to_header->h_reserved[n] =
ext2fs_swab32(from_header->h_reserved[n]);
@@ -124,6 +125,7 @@ void ext2fs_swap_ext_attr(char *to, char
ext2fs_swab32(from_entry->e_value_block);
to_entry->e_value_size =
ext2fs_swab32(from_entry->e_value_size);
+ to_entry->e_hash = ext2fs_swab32(from_entry->e_hash);
from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
to_entry = EXT2_EXT_ATTR_NEXT(to_entry);
}

Thanks,
Kalpak.