Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Tony Ambardar 67a57230b4 bpf: Fix sysfs export of empty BTF section ... commit e23bb04b0c938588eae41b7f4712b722290ed2b8 upstream. If BTF data is missing or removed from the ELF section it is still exported via sysfs as a zero-length file: root@OpenWrt:/# ls -l /sys/kernel/btf/vmlinux -r--r--r-- 1 root root 0 Jul 18 02:59 /sys/kernel/btf/vmlinux Moreover, reads from this file succeed and leak kernel data: root@OpenWrt:/# hexdump -C /sys/kernel/btf/vmlinux|head -10 000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 000cc0 00 00 00 00 00 00 00 00 00 00 00 00 80 83 b0 80 |................| 000cd0 00 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 000ce0 00 00 00 00 00 00 00 00 00 00 00 00 57 ac 6e 9d |............W.n.| 000cf0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 002650 00 00 00 00 00 00 00 10 00 00 00 01 00 00 00 01 |................| 002660 80 82 9a c4 80 85 97 80 81 a9 51 68 00 00 00 02 |..........Qh....| 002670 80 25 44 dc 80 85 97 80 81 a9 50 24 81 ab c4 60 |.%D.......P$...`| This situation was first observed with kernel 5.4.x, cross-compiled for a MIPS target system. Fix by adding a sanity-check for export of zero-length data sections. Fixes: 341dfcf8d7 ("btf: expose BTF info through sysfs") Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/b38db205a66238f70823039a8c531535864eaac5.1600417359.git.Tony.Ambardar@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-10-14 10:32:58 +02:00
..
arraymap.c
bpf_lru_list.c
bpf_lru_list.h
btf.c	bpf: Explicitly memset some bpf info structures declared on the stack	2020-04-02 15:11:01 +02:00
cgroup.c	bpf: Don't return EINVAL from {get,set}sockopt when optlen > PAGE_SIZE	2020-06-30 15:36:56 -04:00
core.c	bpf: Fix use after free in subprog's jited symbol removal	2019-10-22 11:26:09 -07:00
cpumap.c	cpumap: Avoid warning when CONFIG_DEBUG_PER_CPU_MAPS is enabled	2020-05-02 08:48:51 +02:00
devmap.c	devmap: Use bpf_map_area_alloc() for allocating hash buckets	2020-06-30 15:36:56 -04:00
disasm.c
disasm.h
hashtab.c	bpf: Remove recursion prevention from rcu free callback	2020-10-01 13:17:36 +02:00
helpers.c
inode.c	bpf: Fix a rcu warning for bpffs map pretty-print	2020-10-01 13:18:19 +02:00
local_storage.c
lpm_trie.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2019-06-22 08:59:24 -04:00
Makefile	btf: expose BTF info through sysfs	2019-08-13 16:14:15 +02:00
map_in_map.c
map_in_map.h
offload.c	bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fill	2020-02-28 17:22:27 +01:00
percpu_freelist.c
percpu_freelist.h
queue_stack_maps.c
reuseport_array.c
stackmap.c	bpf/stackmap: Fix deadlock with rq_lock in bpf_get_stack()	2019-12-31 16:44:09 +01:00
syscall.c	bpf: sockmap: Require attach_bpf_fd when detaching a program	2020-08-07 09:34:02 +02:00
sysfs_btf.c	bpf: Fix sysfs export of empty BTF section	2020-10-14 10:32:58 +02:00
tnum.c	bpf: Fix incorrect verifier simulation of ARSH under ALU32	2020-01-23 08:22:44 +01:00
verifier.c	bpf: Forbid XADD on spilled pointers for unprivileged users	2020-05-02 08:48:46 +02:00
xskmap.c	bpf/xskmap: Return ERR_PTR for failure case instead of NULL.	2019-09-25 22:14:16 +02:00