Attachment 313174 Details for Bug 457507 – Proposed backported patch

[patch] Proposed backported patch

patch (text/plain), 2.03 KB, created by Eugene Teo (Security Response) on 2008-08-01 09:54:34 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Eugene Teo (Security Response)

Created: 2008-08-01 09:54:34 UTC

Size: 2.03 KB

patch

obsolete

>[mrg-1] kernel: tmpfs: fix kernel BUG in shmem_delete_inode
>
>This is for bz#457507
>
>Backport of upstream commit 14fcc23fdc78e9d32372553ccf21758a9bd56fa1
>
>SuSE's insserve initscript ordering program hits kernel BUG at mm/shmem.c:814
>on 2.6.26.  It's using posix_fadvise on directories, and the shmem_readpage
>method added in 2.6.23 is letting POSIX_FADV_WILLNEED allocate useless pages
>to a tmpfs directory, incrementing i_blocks count but never decrementing it.
>
>Fix this by assigning shmem_aops (pointing to readpage and writepage and
>set_page_dirty) only when it's needed, on a regular file or a long symlink.
>
>Many thanks to Kel for outstanding bugreport and steps to reproduce it.
>
>Signed-off-by: Eugene Teo <eteo@redhat.com>
>---
> mm/shmem.c |    3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
>diff -uprN -X kernel-rt-2.6.24.7-74.el5rt/Documentation/dontdiff kernel-rt-2.6.24.7-74.el5rt.default/mm/shmem.c kernel-rt-2.6.24.7-74.el5rt/mm/shmem.c
>--- kernel-rt-2.6.24.7-74.el5rt.default/mm/shmem.c	2008-08-01 13:55:27.000000000 +0800
>+++ kernel-rt-2.6.24.7-74.el5rt/mm/shmem.c	2008-08-01 17:13:20.000000000 +0800
>@@ -1415,7 +1415,6 @@ shmem_get_inode(struct super_block *sb, 
> 		inode->i_uid = current->fsuid;
> 		inode->i_gid = current->fsgid;
> 		inode->i_blocks = 0;
>-		inode->i_mapping->a_ops = &shmem_aops;
> 		inode->i_mapping->backing_dev_info = &shmem_backing_dev_info;
> 		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
> 		inode->i_generation = get_seconds();
>@@ -1430,6 +1429,7 @@ shmem_get_inode(struct super_block *sb, 
> 			init_special_inode(inode, mode, dev);
> 			break;
> 		case S_IFREG:
>+			inode->i_mapping->a_ops = &shmem_aops;
> 			inode->i_op = &shmem_inode_operations;
> 			inode->i_fop = &shmem_file_operations;
> 			mpol_shared_policy_init(&info->policy, sbinfo->policy,
>@@ -1924,6 +1924,7 @@ static int shmem_symlink(struct inode *d
> 			iput(inode);
> 			return error;
> 		}
>+		inode->i_mapping->a_ops = &shmem_aops;
> 		inode->i_op = &shmem_symlink_inode_operations;
> 		kaddr = kmap_atomic(page, KM_USER0);
> 		memcpy(kaddr, symname, len);

Actions: View | Diff

Attachments on bug 457507: 313169 | 313174 | 314678