Messages in this thread Patch in this message | | | From | Neil Brown <> | Date | Fri, 20 Jul 2007 16:41:33 +1000 | Subject | Re: BUG: unable to handle kernel NULL pointer dereference - nfs v3 |
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On Thursday July 19, satyam.sharma@gmail.com wrote: > Ugh, not a good day for me today ... my earlier conclusion was right, > but not the reasoning behind it ... hopefully this time I'll do better :-)
Looks good. Thanks for your helpful analysis.
> > 0x34 bytes is the offset of ex_uuid in struct fh_export. > %ecx == 0, which means ex_uuid was NULL.
Yup. That shouldn't happen, but I can see that it is possible.
There was another case were ex_uuid could conceivably be referenced while NULL that I fixed a little while ago. Looks like I need to fix this one too. Something like the following.
Thanks, NeilBrown
Signed-off-by: Neil Brown <neilb@suse.de>
### Diffstat output ./fs/nfsd/nfsfh.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)
diff .prev/fs/nfsd/nfsfh.c ./fs/nfsd/nfsfh.c --- .prev/fs/nfsd/nfsfh.c 2007-07-13 17:41:48.000000000 +1000 +++ ./fs/nfsd/nfsfh.c 2007-07-20 12:53:36.000000000 +1000 @@ -566,13 +566,23 @@ enum fsid_source fsid_source(struct svc_ case FSID_DEV: case FSID_ENCODE_DEV: case FSID_MAJOR_MINOR: - return FSIDSOURCE_DEV; + if (fhp->fh_export->ex_dentry->d_inode->i_sb->s_type->fs_flags + & FS_REQUIRES_DEV) + return FSIDSOURCE_DEV; + break; case FSID_NUM: - return FSIDSOURCE_FSID; - default: if (fhp->fh_export->ex_flags & NFSEXP_FSID) return FSIDSOURCE_FSID; - else - return FSIDSOURCE_UUID; + break; + default: + break; } + /* either a UUID type filehandle, or the filehandle doesn't + * match the export. + */ + if (fhp->fh_export->ex_flags & NFSEXP_FSID) + return FSIDSOURCE_FSID; + if (fhp->fh_export->ex_uuid) + return FSIDSOURCE_UUID; + return FSIDSOURCE_DEV; } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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