diff options
| author | Vasily Averin <vvs@virtuozzo.com> | 2020-01-25 12:10:02 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-24 08:34:51 +0100 |
| commit | ca2b45936522f128c6b7b26399fb316be2f35af1 (patch) | |
| tree | 16fe0bd878252320c1755aea4ec0fb489e7e4caa /kernel | |
| parent | 35c9bcb672e36fc64b84b1b7b3b8ff93c8b6cc49 (diff) | |
bpf: map_seq_next should always increase position index
[ Upstream commit 90435a7891a2259b0f74c5a1bc5600d0d64cba8f ]
If seq_file .next fuction does not change position index,
read after some lseek can generate an unexpected output.
See also: https://bugzilla.kernel.org/show_bug.cgi?id=206283
v1 -> v2: removed missed increment in end of function
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/eca84fdd-c374-a154-d874-6c7b55fc3bc4@virtuozzo.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/inode.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index dc9d7ac8228d..c04815bb15cc 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -198,6 +198,7 @@ static void *map_seq_next(struct seq_file *m, void *v, loff_t *pos) void *key = map_iter(m)->key; void *prev_key; + (*pos)++; if (map_iter(m)->done) return NULL; @@ -210,8 +211,6 @@ static void *map_seq_next(struct seq_file *m, void *v, loff_t *pos) map_iter(m)->done = true; return NULL; } - - ++(*pos); return key; } |