diff options
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/trace.c | 65 | ||||
-rw-r--r-- | kernel/trace/trace_events.c | 9 | ||||
-rw-r--r-- | kernel/trace/trace_functions_graph.c | 11 | ||||
-rw-r--r-- | kernel/trace/trace_seq.c | 177 |
4 files changed, 140 insertions, 122 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index ce11fa50a2f0..1af4f8f2ab5d 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -939,19 +939,20 @@ out: return ret; } +/* TODO add a seq_buf_to_buffer() */ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) { int len; - if (s->len <= s->readpos) + if (trace_seq_used(s) <= s->seq.readpos) return -EBUSY; - len = s->len - s->readpos; + len = trace_seq_used(s) - s->seq.readpos; if (cnt > len) cnt = len; - memcpy(buf, s->buffer + s->readpos, cnt); + memcpy(buf, s->buffer + s->seq.readpos, cnt); - s->readpos += cnt; + s->seq.readpos += cnt; return cnt; } @@ -4313,6 +4314,8 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) goto out; } + trace_seq_init(&iter->seq); + /* * We make a copy of the current tracer to avoid concurrent * changes on it while we are reading. @@ -4506,18 +4509,18 @@ waitagain: trace_access_lock(iter->cpu_file); while (trace_find_next_entry_inc(iter) != NULL) { enum print_line_t ret; - int len = iter->seq.len; + int save_len = iter->seq.seq.len; ret = print_trace_line(iter); if (ret == TRACE_TYPE_PARTIAL_LINE) { /* don't print partial lines */ - iter->seq.len = len; + iter->seq.seq.len = save_len; break; } if (ret != TRACE_TYPE_NO_CONSUME) trace_consume(iter); - if (iter->seq.len >= cnt) + if (trace_seq_used(&iter->seq) >= cnt) break; /* @@ -4533,7 +4536,7 @@ waitagain: /* Now copy what we have to the user */ sret = trace_seq_to_user(&iter->seq, ubuf, cnt); - if (iter->seq.readpos >= iter->seq.len) + if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) trace_seq_init(&iter->seq); /* @@ -4567,20 +4570,33 @@ static size_t tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) { size_t count; + int save_len; int ret; /* Seq buffer is page-sized, exactly what we need. */ for (;;) { - count = iter->seq.len; + save_len = iter->seq.seq.len; ret = print_trace_line(iter); - count = iter->seq.len - count; - if (rem < count) { - rem = 0; - iter->seq.len -= count; + + if (trace_seq_has_overflowed(&iter->seq)) { + iter->seq.seq.len = save_len; break; } + + /* + * This should not be hit, because it should only + * be set if the iter->seq overflowed. But check it + * anyway to be safe. + */ if (ret == TRACE_TYPE_PARTIAL_LINE) { - iter->seq.len -= count; + iter->seq.seq.len = save_len; + break; + } + + count = trace_seq_used(&iter->seq) - save_len; + if (rem < count) { + rem = 0; + iter->seq.seq.len = save_len; break; } @@ -4661,13 +4677,13 @@ static ssize_t tracing_splice_read_pipe(struct file *filp, /* Copy the data into the page, so we can start over. */ ret = trace_seq_to_buffer(&iter->seq, page_address(spd.pages[i]), - iter->seq.len); + trace_seq_used(&iter->seq)); if (ret < 0) { __free_page(spd.pages[i]); break; } spd.partial[i].offset = 0; - spd.partial[i].len = iter->seq.len; + spd.partial[i].len = trace_seq_used(&iter->seq); trace_seq_init(&iter->seq); } @@ -5667,7 +5683,8 @@ tracing_stats_read(struct file *filp, char __user *ubuf, cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); trace_seq_printf(s, "read events: %ld\n", cnt); - count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); + count = simple_read_from_buffer(ubuf, count, ppos, + s->buffer, trace_seq_used(s)); kfree(s); @@ -6630,11 +6647,19 @@ void trace_printk_seq(struct trace_seq *s) { /* Probably should print a warning here. */ - if (s->len >= TRACE_MAX_PRINT) - s->len = TRACE_MAX_PRINT; + if (s->seq.len >= TRACE_MAX_PRINT) + s->seq.len = TRACE_MAX_PRINT; + + /* + * More paranoid code. Although the buffer size is set to + * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just + * an extra layer of protection. + */ + if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) + s->seq.len = s->seq.size - 1; /* should be zero ended, but we are paranoid. */ - s->buffer[s->len] = 0; + s->buffer[s->seq.len] = 0; printk(KERN_TRACE "%s", s->buffer); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 139716bcef7a..d0e4f92b5eb6 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -1044,7 +1044,8 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, mutex_unlock(&event_mutex); if (file) - r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); + r = simple_read_from_buffer(ubuf, cnt, ppos, + s->buffer, trace_seq_used(s)); kfree(s); @@ -1210,7 +1211,8 @@ subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, trace_seq_init(s); print_subsystem_event_filter(system, s); - r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); + r = simple_read_from_buffer(ubuf, cnt, ppos, + s->buffer, trace_seq_used(s)); kfree(s); @@ -1265,7 +1267,8 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) trace_seq_init(s); func(s); - r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len); + r = simple_read_from_buffer(ubuf, cnt, ppos, + s->buffer, trace_seq_used(s)); kfree(s); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 6c2ab955018c..ba476009e5de 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -1136,14 +1136,17 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, return ret; } + if (trace_seq_has_overflowed(s)) + goto out; + /* Strip ending newline */ - if (s->buffer[s->len - 1] == '\n') { - s->buffer[s->len - 1] = '\0'; - s->len--; + if (s->buffer[s->seq.len - 1] == '\n') { + s->buffer[s->seq.len - 1] = '\0'; + s->seq.len--; } trace_seq_puts(s, " */\n"); - + out: return trace_handle_return(s); } diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c index fabfa0f190a3..f8b45d8792f9 100644 --- a/kernel/trace/trace_seq.c +++ b/kernel/trace/trace_seq.c @@ -27,10 +27,19 @@ #include <linux/trace_seq.h> /* How much buffer is left on the trace_seq? */ -#define TRACE_SEQ_BUF_LEFT(s) ((PAGE_SIZE - 1) - (s)->len) +#define TRACE_SEQ_BUF_LEFT(s) seq_buf_buffer_left(&(s)->seq) /* How much buffer is written? */ -#define TRACE_SEQ_BUF_USED(s) min((s)->len, (unsigned int)(PAGE_SIZE - 1)) +#define TRACE_SEQ_BUF_USED(s) seq_buf_used(&(s)->seq) + +/* + * trace_seq should work with being initialized with 0s. + */ +static inline void __trace_seq_init(struct trace_seq *s) +{ + if (unlikely(!s->seq.size)) + trace_seq_init(s); +} /** * trace_print_seq - move the contents of trace_seq into a seq_file @@ -43,10 +52,11 @@ */ int trace_print_seq(struct seq_file *m, struct trace_seq *s) { - unsigned int len = TRACE_SEQ_BUF_USED(s); int ret; - ret = seq_write(m, s->buffer, len); + __trace_seq_init(s); + + ret = seq_buf_print_seq(m, &s->seq); /* * Only reset this buffer if we successfully wrote to the @@ -72,24 +82,23 @@ int trace_print_seq(struct seq_file *m, struct trace_seq *s) */ void trace_seq_printf(struct trace_seq *s, const char *fmt, ...) { - unsigned int len = TRACE_SEQ_BUF_LEFT(s); + unsigned int save_len = s->seq.len; va_list ap; - int ret; - if (s->full || !len) + if (s->full) return; + __trace_seq_init(s); + va_start(ap, fmt); - ret = vsnprintf(s->buffer + s->len, len, fmt, ap); + seq_buf_vprintf(&s->seq, fmt, ap); va_end(ap); /* If we can't write it all, don't bother writing anything */ - if (ret >= len) { + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; s->full = 1; - return; } - - s->len += ret; } EXPORT_SYMBOL_GPL(trace_seq_printf); @@ -104,14 +113,19 @@ EXPORT_SYMBOL_GPL(trace_seq_printf); void trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp, int nmaskbits) { - unsigned int len = TRACE_SEQ_BUF_LEFT(s); - int ret; + unsigned int save_len = s->seq.len; - if (s->full || !len) + if (s->full) return; - ret = bitmap_scnprintf(s->buffer + s->len, len, maskp, nmaskbits); - s->len += ret; + __trace_seq_init(s); + + seq_buf_bitmask(&s->seq, maskp, nmaskbits); + + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; + s->full = 1; + } } EXPORT_SYMBOL_GPL(trace_seq_bitmask); @@ -128,21 +142,20 @@ EXPORT_SYMBOL_GPL(trace_seq_bitmask); */ void trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args) { - unsigned int len = TRACE_SEQ_BUF_LEFT(s); - int ret; + unsigned int save_len = s->seq.len; - if (s->full || !len) + if (s->full) return; - ret = vsnprintf(s->buffer + s->len, len, fmt, args); + __trace_seq_init(s); + + seq_buf_vprintf(&s->seq, fmt, args); /* If we can't write it all, don't bother writing anything */ - if (ret >= len) { + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; s->full = 1; - return; } - - s->len += ret; } EXPORT_SYMBOL_GPL(trace_seq_vprintf); @@ -163,21 +176,21 @@ EXPORT_SYMBOL_GPL(trace_seq_vprintf); */ void trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary) { - unsigned int len = TRACE_SEQ_BUF_LEFT(s); - int ret; + unsigned int save_len = s->seq.len; - if (s->full || !len) + if (s->full) return; - ret = bstr_printf(s->buffer + s->len, len, fmt, binary); + __trace_seq_init(s); + + seq_buf_bprintf(&s->seq, fmt, binary); /* If we can't write it all, don't bother writing anything */ - if (ret >= len) { + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; s->full = 1; return; } - - s->len += ret; } EXPORT_SYMBOL_GPL(trace_seq_bprintf); @@ -198,13 +211,14 @@ void trace_seq_puts(struct trace_seq *s, const char *str) if (s->full) return; + __trace_seq_init(s); + if (len > TRACE_SEQ_BUF_LEFT(s)) { s->full = 1; return; } - memcpy(s->buffer + s->len, str, len); - s->len += len; + seq_buf_putmem(&s->seq, str, len); } EXPORT_SYMBOL_GPL(trace_seq_puts); @@ -223,12 +237,14 @@ void trace_seq_putc(struct trace_seq *s, unsigned char c) if (s->full) return; + __trace_seq_init(s); + if (TRACE_SEQ_BUF_LEFT(s) < 1) { s->full = 1; return; } - s->buffer[s->len++] = c; + seq_buf_putc(&s->seq, c); } EXPORT_SYMBOL_GPL(trace_seq_putc); @@ -247,19 +263,17 @@ void trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len) if (s->full) return; + __trace_seq_init(s); + if (len > TRACE_SEQ_BUF_LEFT(s)) { s->full = 1; return; } - memcpy(s->buffer + s->len, mem, len); - s->len += len; + seq_buf_putmem(&s->seq, mem, len); } EXPORT_SYMBOL_GPL(trace_seq_putmem); -#define MAX_MEMHEX_BYTES 8U -#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1) - /** * trace_seq_putmem_hex - write raw memory into the buffer in ASCII hex * @s: trace sequence descriptor @@ -273,32 +287,26 @@ EXPORT_SYMBOL_GPL(trace_seq_putmem); void trace_seq_putmem_hex(struct trace_seq *s, const void *mem, unsigned int len) { - unsigned char hex[HEX_CHARS]; - const unsigned char *data = mem; - unsigned int start_len; - int i, j; + unsigned int save_len = s->seq.len; if (s->full) return; - while (len) { - start_len = min(len, HEX_CHARS - 1); -#ifdef __BIG_ENDIAN - for (i = 0, j = 0; i < start_len; i++) { -#else - for (i = start_len-1, j = 0; i >= 0; i--) { -#endif - hex[j++] = hex_asc_hi(data[i]); - hex[j++] = hex_asc_lo(data[i]); - } - if (WARN_ON_ONCE(j == 0 || j/2 > len)) - break; - - /* j increments twice per loop */ - len -= j / 2; - hex[j++] = ' '; - - trace_seq_putmem(s, hex, j); + __trace_seq_init(s); + + /* Each byte is represented by two chars */ + if (len * 2 > TRACE_SEQ_BUF_LEFT(s)) { + s->full = 1; + return; + } + + /* The added spaces can still cause an overflow */ + seq_buf_putmem_hex(&s->seq, mem, len); + + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; + s->full = 1; + return; } } EXPORT_SYMBOL_GPL(trace_seq_putmem_hex); @@ -317,30 +325,27 @@ EXPORT_SYMBOL_GPL(trace_seq_putmem_hex); */ int trace_seq_path(struct trace_seq *s, const struct path *path) { - unsigned char *p; + unsigned int save_len = s->seq.len; if (s->full) return 0; + __trace_seq_init(s); + if (TRACE_SEQ_BUF_LEFT(s) < 1) { s->full = 1; return 0; } - p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len); - if (!IS_ERR(p)) { - p = mangle_path(s->buffer + s->len, p, "\n"); - if (p) { - s->len = p - s->buffer; - return 1; - } - } else { - s->buffer[s->len++] = '?'; - return 1; + seq_buf_path(&s->seq, path, "\n"); + + if (unlikely(seq_buf_has_overflowed(&s->seq))) { + s->seq.len = save_len; + s->full = 1; + return 0; } - s->full = 1; - return 0; + return 1; } EXPORT_SYMBOL_GPL(trace_seq_path); @@ -366,25 +371,7 @@ EXPORT_SYMBOL_GPL(trace_seq_path); */ int trace_seq_to_user(struct trace_seq *s, char __user *ubuf, int cnt) { - int len; - int ret; - - if (!cnt) - return 0; - - if (s->len <= s->readpos) - return -EBUSY; - - len = s->len - s->readpos; - if (cnt > len) - cnt = len; - ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); - if (ret == cnt) - return -EFAULT; - - cnt -= ret; - - s->readpos += cnt; - return cnt; + __trace_seq_init(s); + return seq_buf_to_user(&s->seq, ubuf, cnt); } EXPORT_SYMBOL_GPL(trace_seq_to_user); 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