From 9a3efb6b661f71d5675369ace9257833f0e78ef3 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 13 Feb 2018 19:00:21 -0800 Subject: bpf: fix memory leak in lpm_trie map_free callback function There is a memory leak happening in lpm_trie map_free callback function trie_free. The trie structure itself does not get freed. Also, trie_free function did not do synchronize_rcu before freeing various data structures. This is incorrect as some rcu_read_lock region(s) for lookup, update, delete or get_next_key may not complete yet. The fix is to add synchronize_rcu in the beginning of trie_free. The useless spin_lock is removed from this function as well. Fixes: b95a5c4db09b ("bpf: add a longest prefix match trie map implementation") Reported-by: Mathieu Malaterre Reported-by: Alexei Starovoitov Tested-by: Mathieu Malaterre Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov --- kernel/bpf/lpm_trie.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c index 7b469d10d0e9..a75e02c961b5 100644 --- a/kernel/bpf/lpm_trie.c +++ b/kernel/bpf/lpm_trie.c @@ -555,7 +555,10 @@ static void trie_free(struct bpf_map *map) struct lpm_trie_node __rcu **slot; struct lpm_trie_node *node; - raw_spin_lock(&trie->lock); + /* Wait for outstanding programs to complete + * update/lookup/delete/get_next_key and free the trie. + */ + synchronize_rcu(); /* Always start at the root and walk down to a node that has no * children. Then free that node, nullify its reference in the parent @@ -569,7 +572,7 @@ static void trie_free(struct bpf_map *map) node = rcu_dereference_protected(*slot, lockdep_is_held(&trie->lock)); if (!node) - goto unlock; + goto out; if (rcu_access_pointer(node->child[0])) { slot = &node->child[0]; @@ -587,8 +590,8 @@ static void trie_free(struct bpf_map *map) } } -unlock: - raw_spin_unlock(&trie->lock); +out: + kfree(trie); } static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key) -- cgit v1.2.3 From 952fad8e323975c4e826b659087d2648777594a6 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 13 Feb 2018 15:33:52 -0800 Subject: bpf: fix sock_map_alloc() error path In case user program provides silly parameters, we want a map_alloc() handler to return an error, not a NULL pointer, otherwise we crash later in find_and_alloc_map() Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: Eric Dumazet Reported-by: syzbot Acked-by: John Fastabend Signed-off-by: Alexei Starovoitov --- kernel/bpf/sockmap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 48c33417d13c..a927e89dad6e 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -521,8 +521,8 @@ static struct smap_psock *smap_init_psock(struct sock *sock, static struct bpf_map *sock_map_alloc(union bpf_attr *attr) { struct bpf_stab *stab; - int err = -EINVAL; u64 cost; + int err; if (!capable(CAP_NET_ADMIN)) return ERR_PTR(-EPERM); @@ -547,6 +547,7 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr) /* make sure page count doesn't overflow */ cost = (u64) stab->map.max_entries * sizeof(struct sock *); + err = -EINVAL; if (cost >= U32_MAX - PAGE_SIZE) goto free_stab; -- cgit v1.2.3 From 7fc17e909edfb9bf421ee04e981d3d474175c7c7 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Wed, 14 Feb 2018 22:17:34 +0800 Subject: bpf: cpumap: use GFP_KERNEL instead of GFP_ATOMIC in __cpu_map_entry_alloc() There're several implications after commit 0bf7800f1799 ("ptr_ring: try vmalloc() when kmalloc() fails") with the using of vmalloc() since can't allow GFP_ATOMIC but mandate GFP_KERNEL. This will lead a WARN since cpumap try to call with GFP_ATOMIC. Fortunately, entry allocation of cpumap can only be done through syscall path which means GFP_ATOMIC is not necessary, so fixing this by replacing GFP_ATOMIC with GFP_KERNEL. Reported-by: syzbot+1a240cdb1f4cc88819df@syzkaller.appspotmail.com Fixes: 0bf7800f1799 ("ptr_ring: try vmalloc() when kmalloc() fails") Cc: Michal Hocko Cc: Daniel Borkmann Cc: Matthew Wilcox Cc: Jesper Dangaard Brouer Cc: akpm@linux-foundation.org Cc: dhowells@redhat.com Cc: hannes@cmpxchg.org Signed-off-by: Jason Wang Acked-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann --- kernel/bpf/cpumap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index fbfdada6caee..a4bb0b34375a 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -334,7 +334,7 @@ static int cpu_map_kthread_run(void *data) static struct bpf_cpu_map_entry *__cpu_map_entry_alloc(u32 qsize, u32 cpu, int map_id) { - gfp_t gfp = GFP_ATOMIC|__GFP_NOWARN; + gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; struct bpf_cpu_map_entry *rcpu; int numa, err; -- cgit v1.2.3 From 9c481b908b011398b1491752271cd1e2c9ad5758 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 14 Feb 2018 15:31:00 +0100 Subject: bpf: fix bpf_prog_array_copy_to_user warning from perf event prog query syzkaller tried to perform a prog query in perf_event_query_prog_array() where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and thus causing a warning due to failed kcalloc() allocation out of the bpf_prog_array_copy_to_user() helper. Given we cannot attach more than 64 programs to a perf event, there's no point in allowing huge ids_len. Therefore, allow a buffer that would fix the maximum number of ids and also add a __GFP_NOWARN to the temporary ids buffer. Fixes: f371b304f12e ("bpf/tracing: allow user space to query prog array on the same tp") Fixes: 0911287ce32b ("bpf: fix bpf_prog_array_copy_to_user() issues") Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov --- kernel/bpf/core.c | 2 +- kernel/trace/bpf_trace.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 29ca9208dcfa..d315b393abdd 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1590,7 +1590,7 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs, * so always copy 'cnt' prog_ids to the user. * In a rare race the user will see zero prog_ids */ - ids = kcalloc(cnt, sizeof(u32), GFP_USER); + ids = kcalloc(cnt, sizeof(u32), GFP_USER | __GFP_NOWARN); if (!ids) return -ENOMEM; rcu_read_lock(); diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index fc2838ac8b78..c0a9e310d715 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -872,6 +872,8 @@ int perf_event_query_prog_array(struct perf_event *event, void __user *info) return -EINVAL; if (copy_from_user(&query, uquery, sizeof(query))) return -EFAULT; + if (query.ids_len > BPF_TRACE_MAX_PROGS) + return -E2BIG; mutex_lock(&bpf_event_mutex); ret = bpf_prog_array_copy_info(event->tp_event->prog_array, -- cgit v1.2.3 From 52c84d36b7e2f8197a9a6174d6f901a7c7afb850 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Wed, 14 Feb 2018 22:42:54 -0800 Subject: tools: bpftool: preserve JSON for batch mode when dumping insns to file Print a "null" JSON object to standard output when bpftool is used to print program instructions to a file, so as to avoid breaking JSON output on batch mode. This null object was added for most commands in a previous commit, but this specific case had been omitted. Fixes: 004b45c0e51a ("tools: bpftool: provide JSON output for all possible commands") Signed-off-by: Quentin Monnet Acked-by: Jakub Kicinski Signed-off-by: Daniel Borkmann --- tools/bpf/bpftool/prog.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index e8e2baaf93c2..e549e329be82 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -774,6 +774,9 @@ static int do_dump(int argc, char **argv) n < 0 ? strerror(errno) : "short write"); goto err_free; } + + if (json_output) + jsonw_null(json_wtr); } else { if (member_len == &info.jited_prog_len) { const char *name = NULL; -- cgit v1.2.3 From 9be6d411b0c473d31f756993b8b41bb16b0679c1 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Wed, 14 Feb 2018 22:42:55 -0800 Subject: tools: bpftool: preserve JSON output on errors on batch file parsing Before this patch, perror() function is used in some cases when bpftool fails to parse its input file in batch mode. This function does not integrate well with the rest of the output when JSON is used, so we replace it by something that is compliant. Most calls to perror() had already been replaced in a previous patch, this one is a leftover. Fixes: d319c8e101c5 ("tools: bpftool: preserve JSON output on errors on batch file parsing") Signed-off-by: Quentin Monnet Acked-by: Jakub Kicinski Signed-off-by: Daniel Borkmann --- tools/bpf/bpftool/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index 3a0396d87c42..185acfa229b5 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -244,7 +244,7 @@ static int do_batch(int argc, char **argv) } if (errno && errno != ENOENT) { - perror("reading batch file failed"); + p_err("reading batch file failed: %s", strerror(errno)); err = -1; } else { p_info("processed %d lines", lines); -- cgit v1.2.3 From 9c2d63b843a5c8a8d0559cc067b5398aa5ec3ffc Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 16 Feb 2018 01:10:29 +0100 Subject: bpf: fix mlock precharge on arraymaps syzkaller recently triggered OOM during percpu map allocation; while there is work in progress by Dennis Zhou to add __GFP_NORETRY semantics for percpu allocator under pressure, there seems also a missing bpf_map_precharge_memlock() check in array map allocation. Given today the actual bpf_map_charge_memlock() happens after the find_and_alloc_map() in syscall path, the bpf_map_precharge_memlock() is there to bail out early before we go and do the map setup work when we find that we hit the limits anyway. Therefore add this for array map as well. Fixes: 6c9059817432 ("bpf: pre-allocate hash map elements") Fixes: a10423b87a7e ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map") Reported-by: syzbot+adb03f3f0bb57ce3acda@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann Cc: Dennis Zhou Signed-off-by: Alexei Starovoitov --- kernel/bpf/arraymap.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index b1f66480135b..a364c408f25a 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -73,11 +73,11 @@ static int array_map_alloc_check(union bpf_attr *attr) static struct bpf_map *array_map_alloc(union bpf_attr *attr) { bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; - int numa_node = bpf_map_attr_numa_node(attr); + int ret, numa_node = bpf_map_attr_numa_node(attr); u32 elem_size, index_mask, max_entries; bool unpriv = !capable(CAP_SYS_ADMIN); + u64 cost, array_size, mask64; struct bpf_array *array; - u64 array_size, mask64; elem_size = round_up(attr->value_size, 8); @@ -109,8 +109,19 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) array_size += (u64) max_entries * elem_size; /* make sure there is no u32 overflow later in round_up() */ - if (array_size >= U32_MAX - PAGE_SIZE) + cost = array_size; + if (cost >= U32_MAX - PAGE_SIZE) return ERR_PTR(-ENOMEM); + if (percpu) { + cost += (u64)attr->max_entries * elem_size * num_possible_cpus(); + if (cost >= U32_MAX - PAGE_SIZE) + return ERR_PTR(-ENOMEM); + } + cost = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT; + + ret = bpf_map_precharge_memlock(cost); + if (ret < 0) + return ERR_PTR(ret); /* allocate all map elements and zero-initialize them */ array = bpf_map_area_alloc(array_size, numa_node); @@ -121,20 +132,13 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) /* copy mandatory map attributes */ bpf_map_init_from_attr(&array->map, attr); + array->map.pages = cost; array->elem_size = elem_size; - if (!percpu) - goto out; - - array_size += (u64) attr->max_entries * elem_size * num_possible_cpus(); - - if (array_size >= U32_MAX - PAGE_SIZE || - bpf_array_alloc_percpu(array)) { + if (percpu && bpf_array_alloc_percpu(array)) { bpf_map_area_free(array); return ERR_PTR(-ENOMEM); } -out: - array->map.pages = round_up(array_size, PAGE_SIZE) >> PAGE_SHIFT; return &array->map; } -- cgit v1.2.3 From b1a2ce825737b0165cc08e6f98f8c0ea1affdd60 Mon Sep 17 00:00:00 2001 From: Jeremy Cline Date: Tue, 20 Feb 2018 01:00:07 +0000 Subject: tools/libbpf: Avoid possibly using uninitialized variable Fixes a GCC maybe-uninitialized warning introduced by 48cca7e44f9f. "text" is only initialized inside the if statement so only print debug info there. Fixes: 48cca7e44f9f ("libbpf: add support for bpf_call") Signed-off-by: Jeremy Cline Signed-off-by: Daniel Borkmann --- tools/lib/bpf/libbpf.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 97073d649c1a..5bbbf285af74 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1060,11 +1060,12 @@ bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, prog->insns = new_insn; prog->main_prog_cnt = prog->insns_cnt; prog->insns_cnt = new_cnt; + pr_debug("added %zd insn from %s to prog %s\n", + text->insns_cnt, text->section_name, + prog->section_name); } insn = &prog->insns[relo->insn_idx]; insn->imm += prog->main_prog_cnt - relo->insn_idx; - pr_debug("added %zd insn from %s to prog %s\n", - text->insns_cnt, text->section_name, prog->section_name); return 0; } -- cgit v1.2.3