Message ID | 65FDECA153DE9A40B78CA281949AC88902A9FBF1@ausx3mps309.aus.amer.dell.com |
---|---|
State | Not Applicable, archived |
Delegated to: | David Miller |
Headers | show |
> -----Original Message----- > From: Chenault, Thomas > Sent: Thursday, May 14, 2009 7:03 AM > To: 'netdev@vger.kernel.org' > Cc: Iyer, Shyam; 'michaelc@cs.wisc.edu' > Subject: [PATCH] net: fix skb_seq_read returning wrong offset/length > for page frag data > > When called with a consumed value that is less than skb_headlen(skb) > bytes into a page frag, skb_seq_read() incorrectly returns an > offset/length relative to skb->data. Ensure that data which should come > from a page frag does. > > Signed-off-by: Thomas Chenault <thomas_chenault@dell.com> > > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > index d152394..e505b53 100644 > --- a/net/core/skbuff.c > +++ b/net/core/skbuff.c > @@ -2288,7 +2288,7 @@ unsigned int skb_seq_read(unsigned int consumed, > const u8 **data, > next_skb: > block_limit = skb_headlen(st->cur_skb) + st->stepped_offset; > > - if (abs_offset < block_limit) { > + if (abs_offset < block_limit && !st->frag_data) { > *data = st->cur_skb->data + (abs_offset - st- > >stepped_offset); > return block_limit - abs_offset; > } Tested-by: Shyam Iyer <shyam_iyer@dell.com> We have seen this scenario affect iSCSI transactions(mainly login) with BCM57710 10G Ethernet(bnx2x driver) card. The iSCSI login errs because the iSCSI PDU header is wrongly read with a wrong ITT value. This error in reading the PDU is seen with this card because of the way the bnx2x driver pushes data to the frags with LRO enabled (through skb->frags[n]). Intel 10G(ixgbe driver) + LRO combination does not expose the issue and the patch doesn't cause a regression either. I am not sure if this patch will break other driver+card configurations. Dave - Does this patch needs more review or you want to queue it up to your tree? I believe it is a critical bug fix. -Shyam Iyer -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: <Shyam_Iyer@Dell.com> Date: Mon, 18 May 2009 18:32:29 +0530 > Dave - Does this patch needs more review or you want to queue it up to > your tree? I believe it is a critical bug fix. I just got back from a week of being away on a cruise, so don't worry it's in my backlog. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: <Thomas_Chenault@Dell.com> Date: Wed, 13 May 2009 20:33:11 -0500 > When called with a consumed value that is less than skb_headlen(skb) > bytes into a page frag, skb_seq_read() incorrectly returns an > offset/length relative to skb->data. Ensure that data which should come > from a page frag does. > > Signed-off-by: Thomas Chenault <thomas_chenault@dell.com> Applied and queued up for -stable, thanks. > @@ -2288,7 +2288,7 @@ unsigned int skb_seq_read(unsigned int consumed, > const u8 **data, Lots of lines in this patch were chopped up by your email client. Please fix this up before you submit any future patches, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d152394..e505b53 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -2288,7 +2288,7 @@ unsigned int skb_seq_read(unsigned int consumed, const u8 **data, next_skb: block_limit = skb_headlen(st->cur_skb) + st->stepped_offset; - if (abs_offset < block_limit) { + if (abs_offset < block_limit && !st->frag_data) { *data = st->cur_skb->data + (abs_offset - st->stepped_offset);
When called with a consumed value that is less than skb_headlen(skb) bytes into a page frag, skb_seq_read() incorrectly returns an offset/length relative to skb->data. Ensure that data which should come from a page frag does. Signed-off-by: Thomas Chenault <thomas_chenault@dell.com> return block_limit - abs_offset; } -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html