Daniel J Blueman
2011-May-04 02:54 UTC
[PATCH, fixed] Prevent oopsing in posix_acl_valid()
If posix_acl_from_xattr() returns an error code, a negative address is dereferenced causing an oops; fix by checking for an error code first. Typo fixed; too much late-night coding. Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com> --- fs/btrfs/acl.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c index 5d505aa..44ea5b9 100644 --- a/fs/btrfs/acl.c +++ b/fs/btrfs/acl.c @@ -178,12 +178,13 @@ static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name, if (value) { acl = posix_acl_from_xattr(value, size); + if (IS_ERR(acl)) + return PTR_ERR(acl); + if (acl) { ret = posix_acl_valid(acl); if (ret) goto out; - } else if (IS_ERR(acl)) { - return PTR_ERR(acl); } } -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/03/2011 10:54 PM, Daniel J Blueman wrote:> If posix_acl_from_xattr() returns an error code, a negative address is > dereferenced causing an oops; fix by checking for an error code first. > > Typo fixed; too much late-night coding. > > Signed-off-by: Daniel J Blueman<daniel.blueman@gmail.com> > --- > fs/btrfs/acl.c | 5 +++-- > 1 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c > index 5d505aa..44ea5b9 100644 > --- a/fs/btrfs/acl.c > +++ b/fs/btrfs/acl.c > @@ -178,12 +178,13 @@ static int btrfs_xattr_acl_set(struct dentry *dentry, const char *name, > > if (value) { > acl = posix_acl_from_xattr(value, size); > + if (IS_ERR(acl)) > + return PTR_ERR(acl); > + > if (acl) { > ret = posix_acl_valid(acl); > if (ret) > goto out; > - } else if (IS_ERR(acl)) { > - return PTR_ERR(acl); > } > } >Actually pulled this down and compiled it this time to make sure it worked. You can add Reviewed-by: Josef Bacik <josef@redhat.com> Thanks, Josef -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Daniel J Blueman
2011-May-10 05:42 UTC
Re: [PATCH, fixed] Prevent oopsing in posix_acl_valid()
Hi Chris, On 4 May 2011 22:40, Josef Bacik <josef@redhat.com> wrote:> On 05/03/2011 10:54 PM, Daniel J Blueman wrote: >> >> If posix_acl_from_xattr() returns an error code, a negative address is >> dereferenced causing an oops; fix by checking for an error code first. >> >> Typo fixed; too much late-night coding. >> >> Signed-off-by: Daniel J Blueman<daniel.blueman@gmail.com> >> --- >> fs/btrfs/acl.c | 5 +++-- >> 1 files changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c >> index 5d505aa..44ea5b9 100644 >> --- a/fs/btrfs/acl.c >> +++ b/fs/btrfs/acl.c >> @@ -178,12 +178,13 @@ static int btrfs_xattr_acl_set(struct dentry >> *dentry, const char *name, >> >> if (value) { >> acl = posix_acl_from_xattr(value, size); >> + if (IS_ERR(acl)) >> + return PTR_ERR(acl); >> + >> if (acl) { >> ret = posix_acl_valid(acl); >> if (ret) >> goto out; >> - } else if (IS_ERR(acl)) { >> - return PTR_ERR(acl); >> } >> } >> > > Actually pulled this down and compiled it this time to make sure it worked. > You can add > > Reviewed-by: Josef Bacik <josef@redhat.com>Will this fix go upstream for the final 2.6.39, now that the last -rc is already out? I hit it in two independent cases when rebooting after other kernel crashes. Thanks, Daniel -- Daniel J Blueman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Excerpts from Daniel J Blueman''s message of 2011-05-10 01:42:45 -0400:> Hi Chris, > > On 4 May 2011 22:40, Josef Bacik <josef@redhat.com> wrote: > > On 05/03/2011 10:54 PM, Daniel J Blueman wrote: > >> > >> If posix_acl_from_xattr() returns an error code, a negative address is > >> dereferenced causing an oops; fix by checking for an error code first. > >> > >> Typo fixed; too much late-night coding. > >> > >> Signed-off-by: Daniel J Blueman<daniel.blueman@gmail.com> > >> --- > >> Â fs/btrfs/acl.c | Â Â 5 +++-- > >> Â 1 files changed, 3 insertions(+), 2 deletions(-) > >> > >> diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c > >> index 5d505aa..44ea5b9 100644 > >> --- a/fs/btrfs/acl.c > >> +++ b/fs/btrfs/acl.c > >> @@ -178,12 +178,13 @@ static int btrfs_xattr_acl_set(struct dentry > >> *dentry, const char *name, > >> > >> Â Â Â Â if (value) { > >> Â Â Â Â Â Â Â Â acl = posix_acl_from_xattr(value, size); > >> + Â Â Â Â Â Â Â if (IS_ERR(acl)) > >> + Â Â Â Â Â Â Â Â Â Â Â return PTR_ERR(acl); > >> + > >> Â Â Â Â Â Â Â Â if (acl) { > >> Â Â Â Â Â Â Â Â Â Â Â Â ret = posix_acl_valid(acl); > >> Â Â Â Â Â Â Â Â Â Â Â Â if (ret) > >> Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â goto out; > >> - Â Â Â Â Â Â Â } else if (IS_ERR(acl)) { > >> - Â Â Â Â Â Â Â Â Â Â Â return PTR_ERR(acl); > >> Â Â Â Â Â Â Â Â } > >> Â Â Â Â } > >> > > > > Actually pulled this down and compiled it this time to make sure it worked. > > Â You can add > > > > Reviewed-by: Josef Bacik <josef@redhat.com> > > Will this fix go upstream for the final 2.6.39, now that the last -rc > is already out? I hit it in two independent cases when rebooting after > other kernel crashes.Yes, I have one other patch to from Li Zefan that I will send along. -chris -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html