1 files changed, 14 insertions, 7 deletions

diff --git a/coreutils/tail.c b/coreutils/tail.c
index 74e14232d..8a112346d 100644
--- a/coreutils/tail.c
+++ b/coreutils/tail.c
@@ -47,13 +47,16 @@ static void tail_xprint_header(const char *fmt, const char *filename)
 static ssize_t tail_read(int fd, char *buf, size_t count)
 {
         ssize_t r;
-        off_t current, end;
+        off_t current;
         struct stat sbuf;
 
-        end = current = lseek(fd, 0, SEEK_CUR);
-        if (!fstat(fd, &sbuf))
-                end = sbuf.st_size;
-        lseek(fd, end < current ? 0 : current, SEEK_SET);
+        /* (A good comment is missing here) */
+        current = lseek(fd, 0, SEEK_CUR);
+        /* /proc files report zero st_size, don't lseek them. */
+        if (fstat(fd, &sbuf) == 0 && sbuf.st_size)
+                if (sbuf.st_size < current)
+                        lseek(fd, 0, SEEK_SET);
+
         r = safe_read(fd, buf, count);
         if (r < 0) {
                 bb_perror_msg(bb_msg_read_error);
@@ -67,8 +70,12 @@ static const char header_fmt[] ALIGN1 = "\n==> %s <==\n";
 
 static unsigned eat_num(const char *p)
 {
-        if (*p == '-') p++;
-        else if (*p == '+') { p++; G.status = EXIT_FAILURE; }
+        if (*p == '-')
+                p++;
+        else if (*p == '+') {
+                p++;
+                G.status = EXIT_FAILURE;
+        }
         return xatou_sfx(p, tail_suffixes);
 }