Begin forwarded message:
Date: Thu, 1 Dec 2005 08:54:18 -0800
From: "Jayachandran C." <[email protected]>
To: [email protected]
Cc: [email protected]
Subject: Errors reported by Coverity in ext3.
[Re-sending to the ext3 list, with minor edits]
I'm in the process of fixing errors generated by the Coverity
tool on the Linux kernel, and I would like your comment on a
set of problems reported in ext3.
The main issue reported is not checking the return code of
ext3_journal_get_write_access() in various places. I would like
to know if there should be error handling in these cases. The
places where the return value is not checked are(in the current
kernel version):
fs/ext3/inode.c ext3_clear_blocks 1829
fs/ext3/namei.c ext3_append 63
fs/ext3/namei.c ext3_delete_entry 1585
fs/ext3/namei.c ext3_mkdir 1745
fs/ext3/namei.c ext3_rename 2273
fs/ext3/namei.c ext3_rename 2328
I have attached the full text of errors reported by Coverity on
kernel version 2.6.13, for reference.
---
1. Error reported in ext3/namei.c
---
CID: 3549
Checker: CHECKED_RETURN
File: fs/ext3/namei.c
Function: ext3_rename
Description: Return value of "__ext3_journal_get_write_access" is not checked
2260 } else {
2261 BUFFER_TRACE(new_bh, "get write access");
Event check_return: Called function "__ext3_journal_get_write_access"
whose return value should be checked (checked 32 out of 39 times)
Event unchecked_value: Return value of
"__ext3_journal_get_write_access" is not checked Also see events:
2262 ext3_journal_get_write_access(handle, new_bh);
---
2. Error reported in ext3/inode.c
---
CID: 3548
Checker: CHECKED_RETURN
File: fs/ext3/inode.c
Function: ext3_clear_blocks
Description: Return value of "__ext3_journal_get_write_access" is not checked
1816 if (bh) {
1817 BUFFER_TRACE(bh, "retaking write access");
Event check_return: Called function "__ext3_journal_get_write_access"
whose return value should be checked (checked 32 out of 39 times)
Event unchecked_value: Return value of
"__ext3_journal_get_write_access" is not checked Also see events:
1818 ext3_journal_get_write_access(handle, bh);
1819 }
---
3. Error reported in ext3/namei.c
---
CID: 3547
Checker: CHECKED_RETURN
File: fs/ext3/namei.c
Function: ext3_delete_entry
Description: Return value of "__ext3_journal_get_write_access" is not checked
1573 if (de == de_del) {
1574 BUFFER_TRACE(bh, "get_write_access");
Event check_return: Called function "__ext3_journal_get_write_access"
whose return value should be checked (checked 32 out of 39 times)
Event unchecked_value: Return value of "__ext3_journal_get_write_access"
is not checked Also see events:
1575 ext3_journal_get_write_access(handle, bh);
1576 if (pde)
4. Error reported in ext3/namei.c
---
CID: 3546
Checker: CHECKED_RETURN
File: fs/ext3/namei.c
Function: ext3_append
Description: Return value of "__ext3_journal_get_write_access" is not checked
58 if ((bh = ext3_bread(handle, inode, *block, 1, err))) {
59 inode->i_size += inode->i_sb->s_blocksize;
60 EXT3_I(inode)->i_disksize = inode->i_size;
Event check_return: Called function "__ext3_journal_get_write_access"
whose return value should be checked (checked 32 out of 39 times)
Event unchecked_value: Return value of "__ext3_journal_get_write_access"
is not checked Also see events:
61 ext3_journal_get_write_access(handle,bh);
62 }
63 return bh;
---
5. Error reported in ext3/balloc.c
---
CID: 3545
Checker: CHECKED_RETURN
File: fs/ext3/balloc.c
Function: ext3_free_blocks_sb
Description: Return value of "test_and_set_bit" is not checked
439 BUFFER_TRACE(bitmap_bh, "set in b_committed_data");
440 J_ASSERT_BH(bitmap_bh,
441 bh2jh(bitmap_bh)->b_committed_data != NULL);
Event check_return: Called function "test_and_set_bit" whose return
value should be checked (checked 83 out of 95 times)
Event unchecked_value: Return value of "test_and_set_bit" is not checked
442 ext3_set_bit_atomic(sb_bgl_lock(sbi, block_group), bit + i,
443 bh2jh(bitmap_bh)->b_committed_data);
--
Thanks,
-
C. Jayachandran [email protected]
On Nov 09, 2006 11:14 -0800, Andrew Morton wrote:
> 2. Error reported in ext3/inode.c
> ---
> CID: 3548
> Checker: CHECKED_RETURN
> File: fs/ext3/inode.c
> Function: ext3_clear_blocks
> Description: Return value of "__ext3_journal_get_write_access" is not checked
>
> 1816 if (bh) {
> 1817 BUFFER_TRACE(bh, "retaking write access");
>
> Event check_return: Called function "__ext3_journal_get_write_access"
> whose return value should be checked (checked 32 out of 39 times)
> Event unchecked_value: Return value of
> "__ext3_journal_get_write_access" is not checked Also see events:
>
> 1818 ext3_journal_get_write_access(handle, bh);
> 1819 }
> ---
Here is a patch we have locally for this one (though against a 2.6.9-RHEL4
kernel, likely usable in mainline with minor tweaks).
Signed-off-by: Andreas Dilger <[email protected]>
- ext3-check-jbd-errors-2.6.9.patch ---------------------------------------
Index: linux-2.6.9-full/include/linux/ext3_fs.h
===================================================================
--- linux-2.6.9-full.orig/include/linux/ext3_fs.h 2006-08-09 17:56:39.000000000 +0400
+++ linux-2.6.9-full/include/linux/ext3_fs.h 2006-08-22 12:36:22.000000000 +0400
@@ -826,6 +826,7 @@ extern void ext3_put_super (struct super
extern void ext3_write_super (struct super_block *);
extern void ext3_write_super_lockfs (struct super_block *);
extern void ext3_unlockfs (struct super_block *);
+extern void ext3_commit_super (struct super_block *, struct ext3_super_block *, int);
extern int ext3_remount (struct super_block *, int *, char *);
extern int ext3_statfs (struct super_block *, struct kstatfs *);
Index: linux-2.6.9-full/fs/ext3/super.c
===================================================================
--- linux-2.6.9-full.orig/fs/ext3/super.c 2006-08-09 17:56:40.000000000 +0400
+++ linux-2.6.9-full/fs/ext3/super.c 2006-08-09 17:56:40.000000000 +0400
@@ -43,7 +43,7 @@ static int ext3_load_journal(struct supe
unsigned long journal_devnum);
static int ext3_create_journal(struct super_block *, struct ext3_super_block *,
int);
-static void ext3_commit_super (struct super_block * sb,
+void ext3_commit_super (struct super_block * sb,
struct ext3_super_block * es,
int sync);
static void ext3_mark_recovery_complete(struct super_block * sb,
@@ -1991,7 +1991,7 @@ static int ext3_create_journal(struct su
return 0;
}
-static void ext3_commit_super (struct super_block * sb,
+void ext3_commit_super (struct super_block * sb,
struct ext3_super_block * es,
int sync)
{
Index: linux-2.6.9-full/fs/ext3/namei.c
===================================================================
--- linux-2.6.9-full.orig/fs/ext3/namei.c 2006-08-09 17:56:40.000000000 +0400
+++ linux-2.6.9-full/fs/ext3/namei.c 2006-08-09 17:56:40.000000000 +0400
@@ -1599,7 +1599,7 @@ static int ext3_delete_entry (handle_t *
struct buffer_head * bh)
{
struct ext3_dir_entry_2 * de, * pde;
- int i;
+ int i, err;
i = 0;
pde = NULL;
@@ -1609,7 +1609,9 @@ static int ext3_delete_entry (handle_t *
return -EIO;
if (de == de_del) {
BUFFER_TRACE(bh, "get_write_access");
- ext3_journal_get_write_access(handle, bh);
+ err = ext3_journal_get_write_access(handle, bh);
+ if (err)
+ return err;
if (pde)
pde->rec_len =
cpu_to_le16(le16_to_cpu(pde->rec_len) +
Index: linux-2.6.9-full/fs/ext3/inode.c
===================================================================
--- linux-2.6.9-full.orig/fs/ext3/inode.c 2006-06-02 23:37:38.000000000 +0400
+++ linux-2.6.9-full/fs/ext3/inode.c 2006-08-22 12:34:28.000000000 +0400
@@ -1807,8 +1812,18 @@ ext3_clear_blocks(handle_t *handle, stru
ext3_mark_inode_dirty(handle, inode);
ext3_journal_test_restart(handle, inode);
if (bh) {
+ int err;
BUFFER_TRACE(bh, "retaking write access");
- ext3_journal_get_write_access(handle, bh);
+ err = ext3_journal_get_write_access(handle, bh);
+ if (err) {
+ struct super_block *sb = inode->i_sb;
+ struct ext3_super_block *es = EXT3_SB(sb)->s_es;
+ printk(KERN_CRIT "EXT3-fs: can't continue truncate\n");
+ EXT3_SB(sb)->s_mount_state |= EXT3_ERROR_FS;
+ es->s_state |= cpu_to_le16(EXT3_ERROR_FS);
+ ext3_commit_super(sb, es, 1);
+ return;
+ }
}
}
Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.