Home Home > GIT Browse > SLE15
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChris Wright <chrisw@sous-sol.org>2008-06-04 09:16:33 -0700
committerChris Wright <chrisw@sous-sol.org>2008-06-06 16:04:46 -0700
commit33afb8403f361919aa5c8fe1d0a4f5ddbfbbea3c (patch)
tree2b95d72be1b19dbb8d3963f8bd9a798652831668
parenta82a9bfebc74862798a3f6949fe6f6a959c1fd4e (diff)
asn1: additional sanity checking during BER decoding (CVE-2008-1673)
upstream commit: ddb2c43594f22843e9f3153da151deaba1a834c5 - Don't trust a length which is greater than the working buffer. An invalid length could cause overflow when calculating buffer size for decoding oid. - An oid length of zero is invalid and allows for an off-by-one error when decoding oid because the first subid actually encodes first 2 subids. - A primitive encoding may not have an indefinite length. Thanks to Wei Wang from McAfee for report. Cc: Steven French <sfrench@us.ibm.com> Cc: stable@kernel.org Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--fs/cifs/asn1.c14
-rw-r--r--net/ipv4/netfilter/nf_nat_snmp_basic.c14
2 files changed, 28 insertions, 0 deletions
diff --git a/fs/cifs/asn1.c b/fs/cifs/asn1.c
index bcda2c6b6a04..5dbba896a7df 100644
--- a/fs/cifs/asn1.c
+++ b/fs/cifs/asn1.c
@@ -186,6 +186,11 @@ asn1_length_decode(struct asn1_ctx *ctx, unsigned int *def, unsigned int *len)
}
}
}
+
+ /* don't trust len bigger than ctx buffer */
+ if (*len > ctx->end - ctx->pointer)
+ return 0;
+
return 1;
}
@@ -203,6 +208,10 @@ asn1_header_decode(struct asn1_ctx *ctx,
if (!asn1_length_decode(ctx, &def, &len))
return 0;
+ /* primitive shall be definite, indefinite shall be constructed */
+ if (*con == ASN1_PRI && !def)
+ return 0;
+
if (def)
*eoc = ctx->pointer + len;
else
@@ -389,6 +398,11 @@ asn1_oid_decode(struct asn1_ctx *ctx,
unsigned long *optr;
size = eoc - ctx->pointer + 1;
+
+ /* first subid actually encodes first two subids */
+ if (size < 2 || size > ULONG_MAX/sizeof(unsigned long))
+ return 0;
+
*oid = kmalloc(size * sizeof(unsigned long), GFP_ATOMIC);
if (*oid == NULL)
return 0;
diff --git a/net/ipv4/netfilter/nf_nat_snmp_basic.c b/net/ipv4/netfilter/nf_nat_snmp_basic.c
index 540ce6ae887c..5f35f0b589db 100644
--- a/net/ipv4/netfilter/nf_nat_snmp_basic.c
+++ b/net/ipv4/netfilter/nf_nat_snmp_basic.c
@@ -231,6 +231,11 @@ static unsigned char asn1_length_decode(struct asn1_ctx *ctx,
}
}
}
+
+ /* don't trust len bigger than ctx buffer */
+ if (*len > ctx->end - ctx->pointer)
+ return 0;
+
return 1;
}
@@ -249,6 +254,10 @@ static unsigned char asn1_header_decode(struct asn1_ctx *ctx,
if (!asn1_length_decode(ctx, &def, &len))
return 0;
+ /* primitive shall be definite, indefinite shall be constructed */
+ if (*con == ASN1_PRI && !def)
+ return 0;
+
if (def)
*eoc = ctx->pointer + len;
else
@@ -433,6 +442,11 @@ static unsigned char asn1_oid_decode(struct asn1_ctx *ctx,
unsigned long *optr;
size = eoc - ctx->pointer + 1;
+
+ /* first subid actually encodes first two subids */
+ if (size < 2 || size > ULONG_MAX/sizeof(unsigned long))
+ return 0;
+
*oid = kmalloc(size * sizeof(unsigned long), GFP_ATOMIC);
if (*oid == NULL) {
if (net_ratelimit())