diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-12-05 12:09:06 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-12-08 11:15:42 +0100 |
| commit | 6e3644aca0bcb572e461ace04d7045beeebb4aaa (patch) | |
| tree | 575aed260dda212633ec79c071121194f83e31a9 | |
| parent | 32646215df00b5dbc79bbeb4df69189fc2a0b234 (diff) | |
proc: proc_skip_spaces() shouldn't think it is working on C strings
commit bce9332220bd677d83b19d21502776ad555a0e73 upstream.
proc_skip_spaces() seems to think it is working on C strings, and ends
up being just a wrapper around skip_spaces() with a really odd calling
convention.
Instead of basing it on skip_spaces(), it should have looked more like
proc_skip_char(), which really is the exact same function (except it
skips a particular character, rather than whitespace). So use that as
inspiration, odd coding and all.
Now the calling convention actually makes sense and works for the
intended purpose.
Reported-and-tested-by: Kyle Zeng <zengyhkyle@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/sysctl.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index bbd0876e100b..9890f93a56fb 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -2041,13 +2041,14 @@ int proc_dostring(struct ctl_table *table, int write, (char __user *)buffer, lenp, ppos); } -static size_t proc_skip_spaces(char **buf) +static void proc_skip_spaces(char **buf, size_t *size) { - size_t ret; - char *tmp = skip_spaces(*buf); - ret = tmp - *buf; - *buf = tmp; - return ret; + while (*size) { + if (!isspace(**buf)) + break; + (*size)--; + (*buf)++; + } } static void proc_skip_char(char **buf, size_t *size, const char v) @@ -2260,7 +2261,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, bool neg; if (write) { - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (!left) break; @@ -2291,7 +2292,7 @@ static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, if (!write && !first && left && !err) err = proc_put_char(&buffer, &left, '\n'); if (write && !err && left) - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (write) { kfree(kbuf); if (first) @@ -2543,7 +2544,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int if (write) { bool neg; - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (!left) break; @@ -2576,7 +2577,7 @@ static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int if (!write && !first && left && !err) err = proc_put_char(&buffer, &left, '\n'); if (write && !err) - left -= proc_skip_spaces(&p); + proc_skip_spaces(&p, &left); if (write) { kfree(kbuf); if (first) |