diff options
| author | Patrick McHardy <kaber@trash.net> | 2006-05-23 15:07:07 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.sfo1.dsl.speakeasy.net> | 2006-05-23 15:15:08 -0700 |
| commit | 7185989db4d926dbef1a2f638c464f35599c83e0 (patch) | |
| tree | bea35167acbd7cc38dfc8b543833cf22f0e8b460 | |
| parent | 14ba3e7b3103a12b6f6a1057a1ecbfb15e1b48c0 (diff) | |
[NETFILTER]: H.323 helper: fix parser error propagation
The condition "> H323_ERROR_STOP" can never be true since H323_ERROR_STOP
is positive and is the highest possible return code, while real errors are
negative, fix the checks. Also only abort on real errors in some spots
that were just interpreting any return value != 0 as error.
Fixes crashes caused by use of stale data after a parsing error occured:
BUG: unable to handle kernel paging request at virtual address bfffffff
printing eip:
c01aa0f8
*pde = 1a801067
*pte = 00000000
Oops: 0000 [#1]
PREEMPT
Modules linked in: ip_nat_h323 ip_conntrack_h323 nfsd exportfs sch_sfq sch_red cls_fw sch_hfsc xt_length ipt_owner xt_MARK iptable_mangle nfs lockd sunrpc pppoe pppoxx
CPU: 0
EIP: 0060:[<c01aa0f8>] Not tainted VLI
EFLAGS: 00210646 (2.6.17-rc4 #8)
EIP is at memmove+0x19/0x22
eax: d77264e9 ebx: d77264e9 ecx: e88d9b17 edx: d77264e9
esi: bfffffff edi: bfffffff ebp: de6a7680 esp: c0349db8
ds: 007b es: 007b ss: 0068
Process asterisk (pid: 3765, threadinfo=c0349000 task=da068540)
Stack: <0>00000006 c0349e5e d77264e3 e09a2b4e e09a38a0 d7726052 d7726124 00000491
00000006 00000006 00000006 00000491 de6a7680 d772601e d7726032 c0349f74
e09a2dc2 00000006 c0349e5e 00000006 00000000 d76dda28 00000491 c0349f74
Call Trace:
[<e09a2b4e>] mangle_contents+0x62/0xfe [ip_nat]
[<e09a2dc2>] ip_nat_mangle_tcp_packet+0xa1/0x191 [ip_nat]
[<e0a2712d>] set_addr+0x74/0x14c [ip_nat_h323]
[<e0ad531e>] process_setup+0x11b/0x29e [ip_conntrack_h323]
[<e0ad534f>] process_setup+0x14c/0x29e [ip_conntrack_h323]
[<e0ad57bd>] process_q931+0x3c/0x142 [ip_conntrack_h323]
[<e0ad5dff>] q931_help+0xe0/0x144 [ip_conntrack_h323]
...
Found by the PROTOS c07-h2250v4 testsuite.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/netfilter/ip_conntrack_helper_h323_asn1.c | 34 |
1 files changed, 19 insertions, 15 deletions
diff --git a/net/ipv4/netfilter/ip_conntrack_helper_h323_asn1.c b/net/ipv4/netfilter/ip_conntrack_helper_h323_asn1.c index 355a53a5b6c..5d04438dda4 100644 --- a/net/ipv4/netfilter/ip_conntrack_helper_h323_asn1.c +++ b/net/ipv4/netfilter/ip_conntrack_helper_h323_asn1.c @@ -528,14 +528,15 @@ int decode_seq(bitstr_t * bs, field_t * f, char *base, int level) /* Decode */ if ((err = (Decoders[son->type]) (bs, son, base, - level + 1)) > - H323_ERROR_STOP) + level + 1)) < + H323_ERROR_NONE) return err; bs->cur = beg + len; bs->bit = 0; } else if ((err = (Decoders[son->type]) (bs, son, base, - level + 1))) + level + 1)) < + H323_ERROR_NONE) return err; } @@ -584,8 +585,8 @@ int decode_seq(bitstr_t * bs, field_t * f, char *base, int level) beg = bs->cur; if ((err = (Decoders[son->type]) (bs, son, base, - level + 1)) > - H323_ERROR_STOP) + level + 1)) < + H323_ERROR_NONE) return err; bs->cur = beg + len; @@ -660,18 +661,20 @@ int decode_seqof(bitstr_t * bs, field_t * f, char *base, int level) i < effective_count ? base : NULL, - level + 1)) > - H323_ERROR_STOP) + level + 1)) < + H323_ERROR_NONE) return err; bs->cur = beg + len; bs->bit = 0; } else - if ((err = (Decoders[son->type]) (bs, son, - i < effective_count ? - base : NULL, - level + 1))) - return err; + if ((err = (Decoders[son->type]) (bs, son, + i < + effective_count ? + base : NULL, + level + 1)) < + H323_ERROR_NONE) + return err; if (base) base += son->offset; @@ -735,13 +738,14 @@ int decode_choice(bitstr_t * bs, field_t * f, char *base, int level) } beg = bs->cur; - if ((err = (Decoders[son->type]) (bs, son, base, level + 1)) > - H323_ERROR_STOP) + if ((err = (Decoders[son->type]) (bs, son, base, level + 1)) < + H323_ERROR_NONE) return err; bs->cur = beg + len; bs->bit = 0; - } else if ((err = (Decoders[son->type]) (bs, son, base, level + 1))) + } else if ((err = (Decoders[son->type]) (bs, son, base, level + 1)) < + H323_ERROR_NONE) return err; return H323_ERROR_NONE; |