Paul Chaignon e7be679124 bpf: Reject %p% format string in bprintf-like helpers ... [ Upstream commit f824274587 ] static const char fmt[] = "%p%"; bpf_trace_printk(fmt, sizeof(fmt)); The above BPF program isn't rejected and causes a kernel warning at runtime: Please remove unsupported %\x00 in format string WARNING: CPU: 1 PID: 7244 at lib/vsprintf.c:2680 format_decode+0x49c/0x5d0 This happens because bpf_bprintf_prepare skips over the second %, detected as punctuation, while processing %p. This patch fixes it by not skipping over punctuation. %\x00 is then processed in the next iteration and rejected. Reported-by: syzbot+e2c932aec5c8a6e1d31c@syzkaller.appspotmail.com Fixes: 48cac3f4a9 ("bpf: Implement formatted output helpers with bstr_printf") Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com> Link: https://lore.kernel.org/r/a0e06cc479faec9e802ae51ba5d66420523251ee.1751395489.git.paul.chaignon@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2025-07-24 08:53:16 +02:00
..
preload
arraymap.c	bpf: Check percpu map value size first	2024-10-17 15:24:15 +02:00
bloom_filter.c	bpf: Check bloom filter map value size	2024-05-17 12:02:11 +02:00
bpf_cgrp_storage.c	bpf: Only fails the busy counter check in bpf_cgrp_storage_get if it creates storage	2025-05-02 07:50:53 +02:00
bpf_inode_storage.c
bpf_iter.c
bpf_local_storage.c	bpf: bpf_local_storage: Always use bpf_mem_alloc in PREEMPT_RT	2025-02-08 09:52:06 +01:00
bpf_lru_list.c	bpf: Adjust free target to avoid global starvation of LRU map	2025-07-17 18:35:21 +02:00
bpf_lru_list.h	bpf: Adjust free target to avoid global starvation of LRU map	2025-07-17 18:35:21 +02:00
bpf_lsm.c
bpf_struct_ops_types.h
bpf_struct_ops.c
bpf_task_storage.c
btf.c	bpf: Check size for BTF-based ctx access of pointer members	2024-12-19 18:11:25 +01:00
cgroup_iter.c
cgroup.c	bpf: Allow pre-ordering for bpf cgroup progs	2025-06-04 14:41:58 +02:00
core.c	bpf: Avoid __bpf_prog_ret0_warn when jit fails	2025-06-19 15:28:18 +02:00
cpumap.c	bpf: report RCU QS in cpumap kthread	2024-03-26 18:20:12 -04:00
cpumask.c
devmap.c	bpf: fix OOB devmap writes when deleting elements	2024-12-14 19:59:56 +01:00
disasm.c
disasm.h
dispatcher.c
hashtab.c	bpf: fix possible endless loop in BPF map iteration	2025-06-04 14:41:53 +02:00
helpers.c	bpf: Reject %p% format string in bprintf-like helpers	2025-07-24 08:53:16 +02:00
inode.c
Kconfig
link_iter.c
local_storage.c
log.c
lpm_trie.c	bpf: Fix exact match conditions in trie_get_next_key()	2024-12-14 19:59:51 +01:00
Makefile
map_in_map.c	bpf: Optimize the free of inner map	2024-06-21 14:38:15 +02:00
map_in_map.h
map_iter.c
memalloc.c
mmap_unlock_work.h
mprog.c
net_namespace.c
offload.c
percpu_freelist.c
percpu_freelist.h
prog_iter.c
queue_stack_maps.c
reuseport_array.c
ringbuf.c	bpf: Use raw_spinlock_t in ringbuf	2025-03-22 12:50:37 -07:00
stackmap.c	bpf: Fix stackmap overflow check on 32-bit arches	2024-03-26 18:19:39 -04:00
syscall.c	bpf: Allow pre-ordering for bpf cgroup progs	2025-06-04 14:41:58 +02:00
sysfs_btf.c
task_iter.c	bpf: Fix iter/task tid filtering	2024-11-01 01:58:25 +01:00
tcx.c
tnum.c
trampoline.c
verifier.c	bpf: don't do clean_live_states when state->loop_entry->branches > 0	2025-06-04 14:42:07 +02:00