| Message ID | 20220225053938.643605-4-matt@codeconstruct.com.au (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 33f5d1a9d9707d1c9ab227aadd9498664e0442e4 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Small fixes for MCTP | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Clearly marked for net-next |
| netdev/fixes_present | success | Fixes tag not required for -next series |
| netdev/subject_prefix | success | Link |
| netdev/cover_letter | success | Series has a cover letter |
| netdev/patch_count | success | Link |
| netdev/header_inline | success | No static functions without inline keyword in header files |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/cc_maintainers | success | CCed 5 of 5 maintainers |
| netdev/build_clang | success | Errors and warnings before: 0 this patch: 0 |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
| netdev/verify_fixes | success | No Fixes tag |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 17 lines checked |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/source_inline | success | Was 0 now: 0 |
diff --git a/drivers/net/mctp/mctp-i2c.c b/drivers/net/mctp/mctp-i2c.c index 470682c88d7e..baf7afac7857 100644 --- a/drivers/net/mctp/mctp-i2c.c +++ b/drivers/net/mctp/mctp-i2c.c @@ -537,6 +537,9 @@ static int mctp_i2c_header_create(struct sk_buff *skb, struct net_device *dev, struct mctp_hdr *mhdr; u8 lldst, llsrc; + if (len > MCTP_I2C_MAXMTU) + return -EMSGSIZE; + lldst = *((u8 *)daddr); llsrc = *((u8 *)saddr); @@ -547,8 +550,6 @@ static int mctp_i2c_header_create(struct sk_buff *skb, struct net_device *dev, hdr->dest_slave = (lldst << 1) & 0xff; hdr->command = MCTP_I2C_COMMANDCODE; hdr->byte_count = len + 1; - if (hdr->byte_count > MCTP_I2C_MAXBLOCK) - return -EMSGSIZE; hdr->source_slave = ((llsrc << 1) & 0xff) | 0x01; mhdr->ver = 0x01;
We should be testing the length before fitting into the u8 byte_count. This is just a sanity check, the MCTP stack should have limited to MTU which is checked, and we check consistency later in mctp_i2c_xmit(). Found by Smatch mctp_i2c_header_create() warn: impossible condition '(hdr->byte_count > 255) => (0-255 > 255)' Signed-off-by: Matt Johnston <matt@codeconstruct.com.au> --- drivers/net/mctp/mctp-i2c.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)