All over the place we define local variables for the various sockopts
that take a bool-like "int" value. Sometimes they are const, sometimes
static, sometimes both, sometimes neither.
Let's clean this up, introduce a common const variable "const_int_one"
(as well as one matching "const_int_zero") and use it everywhere, all
acorss the codebase.
Let's use structured initialization, but more importantly, let's
increase salen by 1, if we reference AF_UNIX sockets in the file system,
so that they also contain the trailing NUL byte. This is what unix(7)
suggests to do, hence follow it.
Insist on NUL termination, just to be safe rather than sorry. The kernel
doesn't require it, but it's really annoying if people rely on this,
hence refuse this early.
This is actually a u16, not a u32, so the kernel complains:
kernel: netlink: 'systemd-network': attribute type 5 has an invalid length
This is due to:
if (nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) {
pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n",
current->comm, type);
}
Presumably this has been working fine in functionality on little-endian
systems, but nobody bothered to try on big-endian systems.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Mempool use is enabled or disabled based on the mempool_use_allowed symbol that
is linked in.
Should fix assert crashes in external programs caused by #9792.
Replaces #10286.
v2:
- use two different source files instead of a gcc constructor
linux/capability.h's CAP_TO_MASK potentially shifts a signed int "1"
(i.e. 32bit wide) left by 31 which means it becomes negative. That's
just weird, and ubsan complains about it. Let's introduce our own macro
CAP_TO_MASK_CORRECTED which doesn't fall into this trap, and make use of
it.
Fixes: #10347
We would read (-1), and then add 1 to it, call message_peek_body(..., 0, ...),
and when trying to make use of the data.
The fuzzer test case is just for one site, but they all look similar.
v2: fix two UINT8_MAX/UINT32_MAX mismatches founds by LGTM
We copied part of the string into a buffer that was off by two.
If the element signature had length one, we'd copy 0 bytes and crash when
looking at the "first" byte. Otherwise, we would crash because strncpy would
not terminate the string.
This is similar to the grandparent commit 'fix calculation of offsets table',
except that now the change is for array elements. Same story as before: we need
to make sure that the offsets increase enough taking alignment into account.
While at it, rename 'p' to 'previous' to match similar code in other places.
The offsets specify the ends of variable length data. We would trust the
incoming data, putting the offsets specified in our message
into the offsets tables after doing some superficial verification.
But when actually reading the data we apply alignment, so we would take
the previous offset, align it, making it bigger then current offset, and
then we'd try to read data of negative length.
In the attached example, the message specifies the following offsets:
[1, 4]
but the alignment of those items is
[1, 8]
so we'd calculate the second item as starting at 8 and ending at 4.
Yu Watanabe
Lennart Poettering
Jason A. Donenfeld
Zbigniew Jędrzejewski-Szmek