Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter
> On 10 Oct 2016, at 21:50, Ilya Dryomov wrote: > > On Mon, Oct 10, 2016 at 3:13 PM, Nikolay Borisov wrote: >> >> >> On 10/10/2016 04:11 PM, Yan, Zheng wrote: >>> On 10 Oct 2016, at 20:56, Nikolay Borisov wrote: In case __ceph_do_getattr returns an error and the retry_op in ceph_read_iter is not READ_INLINE, then it's possible to invoke __free_page on a page which is NULL, this naturally leads to a crash. This can happen when, for example, a process waiting on a MDS reply receives sigterm. Fix this by explicitly checking whether the page is set or not. Signed-off-by: Nikolay Borisov Link: http://www.spinics.net/lists/ceph-users/msg31592.html --- Inverted the condition, so resending with correct condition this time. fs/ceph/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 3c68e6aee2f0..7413313ae6c8 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -929,7 +929,8 @@ again: statret = __ceph_do_getattr(inode, page, CEPH_STAT_CAP_INLINE_DATA, !!page); if (statret < 0) { - __free_page(page); +if (page) +__free_page(page); if (statret == -ENODATA) { BUG_ON(retry_op != READ_INLINE); goto again; — >>> Reviewed-by: Yan, Zheng >> >> I believe this needs to also be tagged as stable. To whomever is going >> to merge it: can you please do that? > > I'll do that. Zheng, do you see any other issues with the killable > wait here? No. this change is obvious, what’s your concern? Regards Yan, Zheng > > Thanks, > >Ilya
Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter
On Mon, Oct 10, 2016 at 3:13 PM, Nikolay Borisov wrote: > > > On 10/10/2016 04:11 PM, Yan, Zheng wrote: >> >>> On 10 Oct 2016, at 20:56, Nikolay Borisov wrote: >>> >>> In case __ceph_do_getattr returns an error and the retry_op in >>> ceph_read_iter is not READ_INLINE, then it's possible to invoke >>> __free_page on a page which is NULL, this naturally leads to a crash. >>> This can happen when, for example, a process waiting on a MDS reply >>> receives sigterm. >>> >>> Fix this by explicitly checking whether the page is set or not. >>> >>> Signed-off-by: Nikolay Borisov >>> Link: http://www.spinics.net/lists/ceph-users/msg31592.html >>> --- >>> >>> Inverted the condition, so resending with correct condition >>> this time. >>> >>> fs/ceph/file.c | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >>> >>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c >>> index 3c68e6aee2f0..7413313ae6c8 100644 >>> --- a/fs/ceph/file.c >>> +++ b/fs/ceph/file.c >>> @@ -929,7 +929,8 @@ again: >>> statret = __ceph_do_getattr(inode, page, >>> CEPH_STAT_CAP_INLINE_DATA, !!page); >>> if (statret < 0) { >>> - __free_page(page); >>> +if (page) >>> +__free_page(page); >>> if (statret == -ENODATA) { >>> BUG_ON(retry_op != READ_INLINE); >>> goto again; >>> — >> Reviewed-by: Yan, Zheng > > I believe this needs to also be tagged as stable. To whomever is going > to merge it: can you please do that? I'll do that. Zheng, do you see any other issues with the killable wait here? Thanks, Ilya
Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter
On 10/10/2016 04:11 PM, Yan, Zheng wrote: > >> On 10 Oct 2016, at 20:56, Nikolay Borisov wrote: >> >> In case __ceph_do_getattr returns an error and the retry_op in >> ceph_read_iter is not READ_INLINE, then it's possible to invoke >> __free_page on a page which is NULL, this naturally leads to a crash. >> This can happen when, for example, a process waiting on a MDS reply >> receives sigterm. >> >> Fix this by explicitly checking whether the page is set or not. >> >> Signed-off-by: Nikolay Borisov >> Link: http://www.spinics.net/lists/ceph-users/msg31592.html >> --- >> >> Inverted the condition, so resending with correct condition >> this time. >> >> fs/ceph/file.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/fs/ceph/file.c b/fs/ceph/file.c >> index 3c68e6aee2f0..7413313ae6c8 100644 >> --- a/fs/ceph/file.c >> +++ b/fs/ceph/file.c >> @@ -929,7 +929,8 @@ again: >> statret = __ceph_do_getattr(inode, page, >> CEPH_STAT_CAP_INLINE_DATA, !!page); >> if (statret < 0) { >> - __free_page(page); >> +if (page) >> +__free_page(page); >> if (statret == -ENODATA) { >> BUG_ON(retry_op != READ_INLINE); >> goto again; >> — > Reviewed-by: Yan, Zheng I believe this needs to also be tagged as stable. To whomever is going to merge it: can you please do that? > >> 2.5.0 >> >
Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter
> On 10 Oct 2016, at 21:13, Nikolay Borisov wrote: > > > > On 10/10/2016 04:11 PM, Yan, Zheng wrote: >> >>> On 10 Oct 2016, at 20:56, Nikolay Borisov wrote: >>> >>> In case __ceph_do_getattr returns an error and the retry_op in >>> ceph_read_iter is not READ_INLINE, then it's possible to invoke >>> __free_page on a page which is NULL, this naturally leads to a crash. >>> This can happen when, for example, a process waiting on a MDS reply >>> receives sigterm. >>> >>> Fix this by explicitly checking whether the page is set or not. >>> >>> Signed-off-by: Nikolay Borisov >>> Link: http://www.spinics.net/lists/ceph-users/msg31592.html >>> --- >>> >>> Inverted the condition, so resending with correct condition >>> this time. >>> >>> fs/ceph/file.c | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >>> >>> diff --git a/fs/ceph/file.c b/fs/ceph/file.c >>> index 3c68e6aee2f0..7413313ae6c8 100644 >>> --- a/fs/ceph/file.c >>> +++ b/fs/ceph/file.c >>> @@ -929,7 +929,8 @@ again: >>> statret = __ceph_do_getattr(inode, page, >>> CEPH_STAT_CAP_INLINE_DATA, !!page); >>> if (statret < 0) { >>> -__free_page(page); >>> + if (page) >>> + __free_page(page); >>> if (statret == -ENODATA) { >>> BUG_ON(retry_op != READ_INLINE); >>> goto again; >>> — >> Reviewed-by: Yan, Zheng > > I believe this needs to also be tagged as stable. To whomever is going > to merge it: can you please do that? > need to get it upstream first > >> >>> 2.5.0 >>> >>
Re: [PATCHv2] ceph: Fix error handling in ceph_read_iter
> On 10 Oct 2016, at 20:56, Nikolay Borisov wrote: > > In case __ceph_do_getattr returns an error and the retry_op in > ceph_read_iter is not READ_INLINE, then it's possible to invoke > __free_page on a page which is NULL, this naturally leads to a crash. > This can happen when, for example, a process waiting on a MDS reply > receives sigterm. > > Fix this by explicitly checking whether the page is set or not. > > Signed-off-by: Nikolay Borisov > Link: http://www.spinics.net/lists/ceph-users/msg31592.html > --- > > Inverted the condition, so resending with correct condition > this time. > > fs/ceph/file.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/fs/ceph/file.c b/fs/ceph/file.c > index 3c68e6aee2f0..7413313ae6c8 100644 > --- a/fs/ceph/file.c > +++ b/fs/ceph/file.c > @@ -929,7 +929,8 @@ again: > statret = __ceph_do_getattr(inode, page, > CEPH_STAT_CAP_INLINE_DATA, !!page); > if (statret < 0) { > - __free_page(page); > + if (page) > + __free_page(page); > if (statret == -ENODATA) { > BUG_ON(retry_op != READ_INLINE); > goto again; > — Reviewed-by: Yan, Zheng > 2.5.0 >
[PATCHv2] ceph: Fix error handling in ceph_read_iter
In case __ceph_do_getattr returns an error and the retry_op in ceph_read_iter is not READ_INLINE, then it's possible to invoke __free_page on a page which is NULL, this naturally leads to a crash. This can happen when, for example, a process waiting on a MDS reply receives sigterm. Fix this by explicitly checking whether the page is set or not. Signed-off-by: Nikolay Borisov Link: http://www.spinics.net/lists/ceph-users/msg31592.html --- Inverted the condition, so resending with correct condition this time. fs/ceph/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 3c68e6aee2f0..7413313ae6c8 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -929,7 +929,8 @@ again: statret = __ceph_do_getattr(inode, page, CEPH_STAT_CAP_INLINE_DATA, !!page); if (statret < 0) { -__free_page(page); + if (page) + __free_page(page); if (statret == -ENODATA) { BUG_ON(retry_op != READ_INLINE); goto again; -- 2.5.0