diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2006-11-29 11:40:22 +0100 |
|---|---|---|
| committer | Adrian Bunk <bunk@stusta.de> | 2006-11-29 11:40:22 +0100 |
| commit | 82182ed2ce8df69635bcfed4baad8bbfae842bc8 (patch) | |
| tree | da5bc595a8151b82150069759097c6dc1d358d4d | |
| parent | cf76a4a8bd6b14d9fc09e2d050253dc70312c273 (diff) | |
add forgotten ->b_data in memcpy() call in ext3/resize.c (oopsable)
sbi->s_group_desc is an array of pointers to buffer_head. memcpy() of
buffer size from address of buffer_head is a bad idea - it will generate
junk in any case, may oops if buffer_head is close to the end of slab
page and next page is not mapped and isn't what was intended there.
IOW, ->b_data is missing in that call. Fortunately, result doesn't go
into the primary on-disk data structures, so only backup ones get crap
written to them; that had allowed this bug to remain unnoticed until
now.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
| -rw-r--r-- | fs/ext3/resize.c | 2 | ||||
| -rw-r--r-- | include/linux/skbuff.h | 15 | ||||
| -rw-r--r-- | net/ipv4/ip_output.c | 4 | ||||
| -rw-r--r-- | net/ipv6/ip6_output.c | 2 |
4 files changed, 19 insertions, 4 deletions
diff --git a/fs/ext3/resize.c b/fs/ext3/resize.c index 14f5f6ea3e7..34b39e9a1e5 100644 --- a/fs/ext3/resize.c +++ b/fs/ext3/resize.c @@ -213,7 +213,7 @@ static int setup_new_group_blocks(struct super_block *sb, goto exit_bh; } lock_buffer(bh); - memcpy(gdb->b_data, sbi->s_group_desc[i], bh->b_size); + memcpy(gdb->b_data, sbi->s_group_desc[i]->b_data, bh->b_size); set_buffer_uptodate(gdb); unlock_buffer(bh); ext3_journal_dirty_metadata(handle, gdb); diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 7e631a54257..9a0e9e78933 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -998,6 +998,21 @@ static inline int pskb_trim(struct sk_buff *skb, unsigned int len) } /** + * pskb_trim_unique - remove end from a paged unique (not cloned) buffer + * @skb: buffer to alter + * @len: new length + * + * This is identical to pskb_trim except that the caller knows that + * the skb is not cloned so we should never get an error due to out- + * of-memory. + */ +static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) +{ + int err = pskb_trim(skb, len); + BUG_ON(err); +} + +/** * skb_orphan - orphan a buffer * @skb: buffer to orphan * diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 8dcba3887f0..b24c6a0c557 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -946,7 +946,7 @@ alloc_new_skb: skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; - skb_trim(skb_prev, maxfraglen); + pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; @@ -1139,7 +1139,7 @@ ssize_t ip_append_page(struct sock *sk, struct page *page, data, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); - skb_trim(skb_prev, maxfraglen); + pskb_trim_unique(skb_prev, maxfraglen); } /* diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 5bf70b1442e..1b528aa1320 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1046,7 +1046,7 @@ alloc_new_skb: skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; - skb_trim(skb_prev, maxfraglen); + pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy < 0) { |