From 3daf19bda4c30fd3b3c3d2fc9d23a20804403139 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 27 Apr 2007 15:21:23 -0700 Subject: [PATCH] [NET]: Revert sk_buff walker cleanups. This reverts 7bd1629d2d0527cd2addcf337ee7128b6fb16a14 The simplification made in that change works with the assumption that the 'offset' parameter to these functions is always positive or zero, which is not true. It can be and often is negative in order to access SKB header values in front of skb->data. Signed-off-by: David S. Miller --- net/appletalk/ddp.c | 25 +++++---- net/core/datagram.c | 50 ++++++++++++------ net/core/skbuff.c | 122 ++++++++++++++++++++++++++++--------------- net/core/user_dma.c | 25 +++++---- net/xfrm/xfrm_algo.c | 22 +++++--- 5 files changed, 158 insertions(+), 86 deletions(-) diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c index 16eda21fb38ce..f6a92a0b7aa6b 100644 --- a/net/appletalk/ddp.c +++ b/net/appletalk/ddp.c @@ -937,11 +937,11 @@ static unsigned long atalk_sum_partial(const unsigned char *data, static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, int len, unsigned long sum) { - int end = skb_headlen(skb); + int start = skb_headlen(skb); int i, copy; /* checksum stuff in header space */ - if ((copy = end - offset) > 0) { + if ( (copy = start - offset) > 0) { if (copy > len) copy = len; sum = atalk_sum_partial(skb->data + offset, copy, sum); @@ -953,9 +953,11 @@ static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, /* checksum stuff in frags */ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { u8 *vaddr; skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; @@ -963,31 +965,36 @@ static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, if (copy > len) copy = len; vaddr = kmap_skb_frag(frag); - sum = atalk_sum_partial(vaddr + frag->page_offset, - copy, sum); + sum = atalk_sum_partial(vaddr + frag->page_offset + + offset - start, copy, sum); kunmap_skb_frag(vaddr); if (!(len -= copy)) return sum; offset += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - sum = atalk_sum_skb(list, 0, copy, sum); + sum = atalk_sum_skb(list, offset - start, + copy, sum); if ((len -= copy) == 0) return sum; offset += copy; } + start = end; } } diff --git a/net/core/datagram.c b/net/core/datagram.c index e1afa76794456..cb056f4761262 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -247,8 +247,8 @@ EXPORT_SYMBOL(skb_kill_datagram); int skb_copy_datagram_iovec(const struct sk_buff *skb, int offset, struct iovec *to, int len) { - int end = skb_headlen(skb); - int i, copy = end - offset; + int start = skb_headlen(skb); + int i, copy = start - offset; /* Copy header. */ if (copy > 0) { @@ -263,9 +263,11 @@ int skb_copy_datagram_iovec(const struct sk_buff *skb, int offset, /* Copy paged appendix. Hmm... why does this look so complicated? */ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { int err; u8 *vaddr; @@ -275,8 +277,8 @@ int skb_copy_datagram_iovec(const struct sk_buff *skb, int offset, if (copy > len) copy = len; vaddr = kmap(page); - err = memcpy_toiovec(to, vaddr + frag->page_offset, - copy); + err = memcpy_toiovec(to, vaddr + frag->page_offset + + offset - start, copy); kunmap(page); if (err) goto fault; @@ -284,24 +286,30 @@ int skb_copy_datagram_iovec(const struct sk_buff *skb, int offset, return 0; offset += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - if (skb_copy_datagram_iovec(list, 0, to, copy)) + if (skb_copy_datagram_iovec(list, + offset - start, + to, copy)) goto fault; if ((len -= copy) == 0) return 0; offset += copy; } + start = end; } } if (!len) @@ -315,9 +323,9 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, u8 __user *to, int len, __wsum *csump) { - int end = skb_headlen(skb); + int start = skb_headlen(skb); int pos = 0; - int i, copy = end - offset; + int i, copy = start - offset; /* Copy header. */ if (copy > 0) { @@ -336,9 +344,11 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { __wsum csum2; int err = 0; @@ -350,7 +360,8 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, copy = len; vaddr = kmap(page); csum2 = csum_and_copy_to_user(vaddr + - frag->page_offset, + frag->page_offset + + offset - start, to, copy, 0, &err); kunmap(page); if (err) @@ -362,20 +373,24 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, to += copy; pos += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list=list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { __wsum csum2 = 0; if (copy > len) copy = len; - if (skb_copy_and_csum_datagram(list, 0, + if (skb_copy_and_csum_datagram(list, + offset - start, to, copy, &csum2)) goto fault; @@ -386,6 +401,7 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, to += copy; pos += copy; } + start = end; } } if (!len) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 32f087b5233e7..142257307fa26 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1045,13 +1045,13 @@ pull_pages: int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len) { int i, copy; - int end = skb_headlen(skb); + int start = skb_headlen(skb); if (offset > (int)skb->len - len) goto fault; /* Copy header. */ - if ((copy = end - offset) > 0) { + if ((copy = start - offset) > 0) { if (copy > len) copy = len; skb_copy_from_linear_data_offset(skb, offset, to, copy); @@ -1062,9 +1062,11 @@ int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len) } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { u8 *vaddr; @@ -1073,8 +1075,8 @@ int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len) vaddr = kmap_skb_frag(&skb_shinfo(skb)->frags[i]); memcpy(to, - vaddr + skb_shinfo(skb)->frags[i].page_offset, - copy); + vaddr + skb_shinfo(skb)->frags[i].page_offset+ + offset - start, copy); kunmap_skb_frag(vaddr); if ((len -= copy) == 0) @@ -1082,25 +1084,30 @@ int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len) offset += copy; to += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - if (skb_copy_bits(list, 0, to, copy)) + if (skb_copy_bits(list, offset - start, + to, copy)) goto fault; if ((len -= copy) == 0) return 0; offset += copy; to += copy; } + start = end; } } if (!len) @@ -1125,12 +1132,12 @@ fault: int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len) { int i, copy; - int end = skb_headlen(skb); + int start = skb_headlen(skb); if (offset > (int)skb->len - len) goto fault; - if ((copy = end - offset) > 0) { + if ((copy = start - offset) > 0) { if (copy > len) copy = len; skb_copy_to_linear_data_offset(skb, offset, from, copy); @@ -1142,9 +1149,11 @@ int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len) for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + frag->size; + end = start + frag->size; if ((copy = end - offset) > 0) { u8 *vaddr; @@ -1152,7 +1161,8 @@ int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len) copy = len; vaddr = kmap_skb_frag(frag); - memcpy(vaddr + frag->page_offset, from, copy); + memcpy(vaddr + frag->page_offset + offset - start, + from, copy); kunmap_skb_frag(vaddr); if ((len -= copy) == 0) @@ -1160,25 +1170,30 @@ int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len) offset += copy; from += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; - end = offset + list->len; + BUG_TRAP(start <= offset + len); + + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - if (skb_store_bits(list, 0, from, copy)) + if (skb_store_bits(list, offset - start, + from, copy)) goto fault; if ((len -= copy) == 0) return 0; offset += copy; from += copy; } + start = end; } } if (!len) @@ -1195,8 +1210,8 @@ EXPORT_SYMBOL(skb_store_bits); __wsum skb_checksum(const struct sk_buff *skb, int offset, int len, __wsum csum) { - int end = skb_headlen(skb); - int i, copy = end - offset; + int start = skb_headlen(skb); + int i, copy = start - offset; int pos = 0; /* Checksum header. */ @@ -1211,9 +1226,11 @@ __wsum skb_checksum(const struct sk_buff *skb, int offset, } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + skb_shinfo(skb)->frags[i].size; + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { __wsum csum2; u8 *vaddr; @@ -1222,8 +1239,8 @@ __wsum skb_checksum(const struct sk_buff *skb, int offset, if (copy > len) copy = len; vaddr = kmap_skb_frag(frag); - csum2 = csum_partial(vaddr + frag->page_offset, - copy, 0); + csum2 = csum_partial(vaddr + frag->page_offset + + offset - start, copy, 0); kunmap_skb_frag(vaddr); csum = csum_block_add(csum, csum2, pos); if (!(len -= copy)) @@ -1231,26 +1248,31 @@ __wsum skb_checksum(const struct sk_buff *skb, int offset, offset += copy; pos += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; - end = offset + list->len; + BUG_TRAP(start <= offset + len); + + end = start + list->len; if ((copy = end - offset) > 0) { __wsum csum2; if (copy > len) copy = len; - csum2 = skb_checksum(list, 0, copy, 0); + csum2 = skb_checksum(list, offset - start, + copy, 0); csum = csum_block_add(csum, csum2, pos); if ((len -= copy) == 0) return csum; offset += copy; pos += copy; } + start = end; } } BUG_ON(len); @@ -1263,8 +1285,8 @@ __wsum skb_checksum(const struct sk_buff *skb, int offset, __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to, int len, __wsum csum) { - int end = skb_headlen(skb); - int i, copy = end - offset; + int start = skb_headlen(skb); + int i, copy = start - offset; int pos = 0; /* Copy header. */ @@ -1281,9 +1303,11 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + skb_shinfo(skb)->frags[i].size; + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { __wsum csum2; u8 *vaddr; @@ -1293,8 +1317,9 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, copy = len; vaddr = kmap_skb_frag(frag); csum2 = csum_partial_copy_nocheck(vaddr + - frag->page_offset, - to, copy, 0); + frag->page_offset + + offset - start, to, + copy, 0); kunmap_skb_frag(vaddr); csum = csum_block_add(csum, csum2, pos); if (!(len -= copy)) @@ -1303,6 +1328,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, to += copy; pos += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { @@ -1310,13 +1336,16 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, for (; list; list = list->next) { __wsum csum2; - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - csum2 = skb_copy_and_csum_bits(list, 0, + csum2 = skb_copy_and_csum_bits(list, + offset - start, to, copy, 0); csum = csum_block_add(csum, csum2, pos); if ((len -= copy) == 0) @@ -1325,6 +1354,7 @@ __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, to += copy; pos += copy; } + start = end; } } BUG_ON(len); @@ -1996,8 +2026,8 @@ void __init skb_init(void) int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len) { - int end = skb_headlen(skb); - int i, copy = end - offset; + int start = skb_headlen(skb); + int i, copy = start - offset; int elt = 0; if (copy > 0) { @@ -2013,39 +2043,45 @@ skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len) } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; if (copy > len) copy = len; sg[elt].page = frag->page; - sg[elt].offset = frag->page_offset; + sg[elt].offset = frag->page_offset+offset-start; sg[elt].length = copy; elt++; if (!(len -= copy)) return elt; offset += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - elt += skb_to_sgvec(list, sg+elt, 0, copy); + elt += skb_to_sgvec(list, sg+elt, offset - start, copy); if ((len -= copy) == 0) return elt; offset += copy; } + start = end; } } BUG_ON(len); diff --git a/net/core/user_dma.c b/net/core/user_dma.c index 89241cdeea3f7..0ad1cd57bc393 100644 --- a/net/core/user_dma.c +++ b/net/core/user_dma.c @@ -49,8 +49,8 @@ int dma_skb_copy_datagram_iovec(struct dma_chan *chan, struct sk_buff *skb, int offset, struct iovec *to, size_t len, struct dma_pinned_list *pinned_list) { - int end = skb_headlen(skb); - int i, copy = end - offset; + int start = skb_headlen(skb); + int i, copy = start - offset; dma_cookie_t cookie = 0; /* Copy header. */ @@ -69,9 +69,11 @@ int dma_skb_copy_datagram_iovec(struct dma_chan *chan, /* Copy paged appendix. Hmm... why does this look so complicated? */ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; copy = end - offset; if ((copy = end - offset) > 0) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; @@ -80,8 +82,8 @@ int dma_skb_copy_datagram_iovec(struct dma_chan *chan, if (copy > len) copy = len; - cookie = dma_memcpy_pg_to_iovec(chan, to, pinned_list, - page, frag->page_offset, copy); + cookie = dma_memcpy_pg_to_iovec(chan, to, pinned_list, page, + frag->page_offset + offset - start, copy); if (cookie < 0) goto fault; len -= copy; @@ -89,21 +91,25 @@ int dma_skb_copy_datagram_iovec(struct dma_chan *chan, goto end; offset += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; copy = end - offset; if (copy > 0) { if (copy > len) copy = len; cookie = dma_skb_copy_datagram_iovec(chan, list, - 0, to, copy, pinned_list); + offset - start, to, copy, + pinned_list); if (cookie < 0) goto fault; len -= copy; @@ -111,6 +117,7 @@ int dma_skb_copy_datagram_iovec(struct dma_chan *chan, goto end; offset += copy; } + start = end; } } diff --git a/net/xfrm/xfrm_algo.c b/net/xfrm/xfrm_algo.c index be529c4241a6b..6249a9405bb83 100644 --- a/net/xfrm/xfrm_algo.c +++ b/net/xfrm/xfrm_algo.c @@ -532,8 +532,8 @@ EXPORT_SYMBOL_GPL(xfrm_count_enc_supported); int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc, int offset, int len, icv_update_fn_t icv_update) { - int end = skb_headlen(skb); - int i, copy = end - offset; + int start = skb_headlen(skb); + int i, copy = start - offset; int err; struct scatterlist sg; @@ -556,9 +556,11 @@ int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc, } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; @@ -566,7 +568,7 @@ int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc, copy = len; sg.page = frag->page; - sg.offset = frag->page_offset; + sg.offset = frag->page_offset + offset-start; sg.length = copy; err = icv_update(desc, &sg, copy); @@ -577,19 +579,22 @@ int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc, return 0; offset += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - err = skb_icv_walk(list, desc, 0, + err = skb_icv_walk(list, desc, offset-start, copy, icv_update); if (unlikely(err)) return err; @@ -597,6 +602,7 @@ int skb_icv_walk(const struct sk_buff *skb, struct hash_desc *desc, return 0; offset += copy; } + start = end; } } BUG_ON(len); -- 2.39.5