opnsense-src/sys
Olivier Certner 3e49891270
sys_procctl(): Make it clear that negative commands are invalid
An initial reading of the preamble of sys_procctl() gives the impression
that no test prevents a malicious user from passing a negative commands
index (in 'uap->com'), which is soon used as an index into the static
array procctl_cmds_info[].

However, a closer examination leads to the conclusion that the existing
code is technically correct.  Indeed, the comparison of 'uap->com' to
the nitems() expression, which expands to a ratio of sizeof(), leads to
a conversion of 'uap->com' to an 'unsigned int' as per Usual Arithmetic
Conversions/Integer Promotions applied by '<=', because sizeof() returns
'size_t' values, and we define 'size_t' as an equivalent of 'unsigned
int' (which is not mandated by the standard, the latter allowing, e.g.,
integers of lower ranks).

With this conversion, negative values of 'uap->com' are automatically
ruled-out since they are converted to very big unsigned integers which
are caught by the test.  An analysis of assembly code produced by LLVM
16 on amd64 and practical tests confirm that no exploitation is possible.

However, the guard code as written is misleading to readers and might
trip up static analysis tools.  Make sure that negative values are
explicitly excluded so that it is immediately clear that EINVAL will be
returned in this case.

Build tested with clang 16 and GCC 12.

Approved by:    markj (mentor)
MFC after:      1 week
Sponsored by:   The FreeBSD Foundation

(cherry picked from commit afc10f8bba3dd293a66461aaca41237c986b6ca7)

Approved by:    emaste (mentor)
2024-04-29 11:48:02 +09:00
..
amd64 vmm(4): Fix a typo in a kernel message 2024-04-28 07:20:46 +02:00
arm arm: Fix a typo in a KASSERT message 2024-04-24 12:20:03 +02:00
arm64 arm64: Remove a double word in a source code comment 2024-04-23 07:23:53 +02:00
bsm timerfd: Move implementation from linux compat to sys/kern 2023-08-24 14:28:56 -06:00
cam cam: Check if cam_simq_alloc fails for the xpt bus during module init 2024-04-08 10:53:43 -07:00
cddl Revert "dtrace: make 'ring' and 'fill' policies imply 'noswitch' flag" 2024-04-21 15:27:11 +03:00
compat linux: ignore setsockopt(IPV6_RECVERR) 2024-04-27 06:59:46 -06:00
conf ice_ddp: Update package to 1.3.36.0 2024-04-24 15:14:48 -07:00
contrib ice_ddp: Update package to 1.3.36.0 2024-04-24 15:14:48 -07:00
crypto ossl: Remove a stray __FBSDID("$FreeBSD$") 2024-03-29 09:53:05 -04:00
ddb ddb: Add sysctl flag CTLFLAG_TUN to loader tunable 2023-10-12 12:08:18 +08:00
dev wtap: Fix typos in kernel messages 2024-04-28 07:20:25 +02:00
dts add allwinner overlays for enabling additional USB ports 2024-02-17 16:15:10 +02:00
fs Revert "nfsd: Fix NFSv4.1/4.2 Claim_Deleg_Cur_FH" 2024-04-27 18:36:04 -07:00
gdb sys: Remove $FreeBSD$: one-line .c pattern 2023-08-16 11:54:36 -06:00
geom geom(4): Fix a typo in a source code comment 2024-04-24 12:19:28 +02:00
gnu sys: Remove $FreeBSD$: one-line .c pattern 2023-08-16 11:54:36 -06:00
i386 i386: Fix a typo in a source code comment 2024-04-27 07:49:27 +02:00
isa isa: Postpone removal of the non-PNP driver until 15 2023-10-30 08:55:08 +08:00
kern sys_procctl(): Make it clear that negative commands are invalid 2024-04-29 11:48:02 +09:00
kgssapi nfscl/kgssapi: Fix Kerberized NFS mounts to pNFS servers 2023-12-23 17:03:58 -08:00
libkern arm64: Mark the armv8 crc32c as supporting BTI 2024-02-19 13:17:47 +00:00
modules ice_ddp: Update package to 1.3.36.0 2024-04-24 15:14:48 -07:00
net Support ARP for 802 networks 2024-04-27 10:45:22 -04:00
net80211 net80211: amrr_init: change order of commands 2024-04-22 17:00:22 +00:00
netgraph ng_socket: Treat EEXIST from kern_kldload() as success 2024-04-16 12:34:56 +08:00
netinet Support ARP for 802 networks 2024-04-27 10:45:22 -04:00
netinet6 carp: check CARP status in in_localip_fib(), in6_localip_fib() 2024-03-28 12:35:45 -07:00
netipsec ipsec esp: avoid dereferencing freed secasindex 2024-03-04 02:27:17 +02:00
netlink netlink: Don't use a zero-length array 2024-04-08 10:58:16 -07:00
netpfil pf tests: Add option to send fragmented packets 2024-04-24 22:11:56 +00:00
netsmb sys: Remove $FreeBSD$: one-line .c pattern 2023-08-16 11:54:36 -06:00
nfs sys: Remove $FreeBSD$: one-line .c pattern 2023-08-16 11:54:36 -06:00
nfsclient sys: Remove $FreeBSD$: one-line .h pattern 2023-08-16 11:54:18 -06:00
nfsserver sys: Remove $FreeBSD$: one-line .h pattern 2023-08-16 11:54:18 -06:00
nlm sys: Remove $FreeBSD$: one-line .c pattern 2023-08-16 11:54:36 -06:00
ofed ibcore: Introduce enum ib_raw_packet_caps from Linux 4.11 2023-11-04 15:22:18 -04:00
opencrypto sys: Remove $FreeBSD$: one-line sh pattern 2023-08-16 11:54:58 -06:00
powerpc busdma: fix page miscount for small segment sizes 2024-04-18 15:09:02 -03:00
riscv busdma: fix page miscount for small segment sizes 2024-04-18 15:09:02 -03:00
rpc NFS: Request use of TCP_USE_DDP for in-kernel TCP sockets 2024-04-12 12:25:27 -07:00
security veriexec: Simplify the initialization of loader tunable 2023-11-13 11:56:57 +08:00
sys sys: Remove two double words in source code comments 2024-04-25 08:17:04 +02:00
teken teken: fix style in teken_wcwidth.h 2023-10-21 17:28:35 +03:00
tests netlink: move NETLINK define to opt_global.h 2023-10-16 09:42:33 +02:00
tools arm_kernel_bothdr.awk: Update to latest ota 2024-04-24 17:57:55 -06:00
ufs Eliminate unnecessary UFS1 integrity checks. 2024-03-04 16:09:10 -08:00
vm vm_reserv_reclaim_contig: Return NULL not false 2024-04-17 10:33:26 -04:00
x86 busdma: fix page miscount for small segment sizes 2024-04-18 15:09:02 -03:00
xdr sys: Remove $FreeBSD$: one-line .c pattern 2023-08-16 11:54:36 -06:00
xen sys: Remove $FreeBSD$: one-line sh pattern 2023-08-16 11:54:58 -06:00
Makefile sys: Remove $FreeBSD$: one-line sh pattern 2023-08-16 11:54:58 -06:00
README.md sys/README.md: Add a section for documentation 2023-08-03 11:07:41 -03:00

FreeBSD Kernel Source:

This directory contains the source files and build glue that make up the FreeBSD kernel and its modules, including both original and contributed software.

Kernel configuration files are located in the conf/ subdirectory of each architecture. GENERIC is the configuration used in release builds. NOTES contains documentation of all possible entries. LINT is a compile-only configuration used to maximize build coverage and detect regressions.

Documentation:

Source code documentation is maintained in a set of man pages, under section 9. These pages are located in share/man/man9, from the top-level of the src tree. Consult intro(9) for an overview of existing pages.

Some additional high-level documentation of the kernel is maintained in the Architecture Handbook.

Source Roadmap:

Directory Description
amd64 AMD64 (64-bit x86) architecture support
arm 32-bit ARM architecture support
arm64 64-bit ARM (AArch64) architecture support
cam Common Access Method storage subsystem - cam(4) and ctl(4)
cddl CDDL-licensed optional sources such as DTrace
conf kernel build glue
compat Linux compatibility layer, FreeBSD 32-bit compatibility
contrib 3rd-party imported software such as OpenZFS
crypto crypto drivers
ddb interactive kernel debugger - ddb(4)
fs most filesystems, excluding UFS, NFS, and ZFS
dev device drivers and other arch independent code
gdb kernel remote GDB stub - gdb(4)
geom GEOM framework - geom(4)
i386 i386 (32-bit x86) architecture support
kern main part of the kernel
libkern libc-like and other support functions for kernel use
modules kernel module infrastructure
net core networking code
net80211 wireless networking (IEEE 802.11) - net80211(4)
netgraph graph-based networking subsystem - netgraph(4)
netinet IPv4 protocol implementation - inet(4)
netinet6 IPv6 protocol implementation - inet6(4)
netipsec IPsec protocol implementation - ipsec(4)
netpfil packet filters - ipfw(4), pf(4), and ipfilter(4)
opencrypto OpenCrypto framework - crypto(7)
powerpc PowerPC/POWER (32 and 64-bit) architecture support
riscv 64-bit RISC-V architecture support
security security facilities - audit(4) and mac(4)
sys kernel headers
tests kernel unit tests
ufs Unix File System - ffs(7)
vm virtual memory system
x86 code shared by AMD64 and i386 architectures