4.9-stable patches

added patches:
	pipe-avoid-round_pipe_size-nr_pages-overflow-on-32-bit.patch

diff --git a/queue-4.9/pipe-avoid-round_pipe_size-nr_pages-overflow-on-32-bit.patch b/queue-4.9/pipe-avoid-round_pipe_size-nr_pages-overflow-on-32-bit.patch
new file mode 100644 (file)
index 0000000..70a9c5b
--- /dev/null
+++ b/queue-4.9/pipe-avoid-round_pipe_size-nr_pages-overflow-on-32-bit.patch
@@ -0,0 +1,115 @@
+From d3f14c485867cfb2e0c48aa88c41d0ef4bf5209c Mon Sep 17 00:00:00 2001
+From: Joe Lawrence <joe.lawrence@redhat.com>
+Date: Fri, 17 Nov 2017 15:29:21 -0800
+Subject: pipe: avoid round_pipe_size() nr_pages overflow on 32-bit
+
+From: Joe Lawrence <joe.lawrence@redhat.com>
+
+commit d3f14c485867cfb2e0c48aa88c41d0ef4bf5209c upstream.
+
+round_pipe_size() contains a right-bit-shift expression which may
+overflow, which would cause undefined results in a subsequent
+roundup_pow_of_two() call.
+
+  static inline unsigned int round_pipe_size(unsigned int size)
+  {
+          unsigned long nr_pages;
+
+          nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+          return roundup_pow_of_two(nr_pages) << PAGE_SHIFT;
+  }
+
+PAGE_SIZE is defined as (1UL << PAGE_SHIFT), so:
+  - 4 bytes wide on 32-bit (0 to 0xffffffff)
+  - 8 bytes wide on 64-bit (0 to 0xffffffffffffffff)
+
+That means that 32-bit round_pipe_size(), nr_pages may overflow to 0:
+
+  size=0x00000000    nr_pages=0x0
+  size=0x00000001    nr_pages=0x1
+  size=0xfffff000    nr_pages=0xfffff
+  size=0xfffff001    nr_pages=0x0         << !
+  size=0xffffffff    nr_pages=0x0         << !
+
+This is bad because roundup_pow_of_two(n) is undefined when n == 0!
+
+64-bit is not a problem as the unsigned int size is 4 bytes wide
+(similar to 32-bit) and the larger, 8 byte wide unsigned long, is
+sufficient to handle the largest value of the bit shift expression:
+
+  size=0xffffffff    nr_pages=100000
+
+Modify round_pipe_size() to return 0 if n == 0 and updates its callers to
+handle accordingly.
+
+Link: http://lkml.kernel.org/r/1507658689-11669-3-git-send-email-joe.lawrence@redhat.com
+Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
+Reported-by: Mikulas Patocka <mpatocka@redhat.com>
+Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
+Cc: Al Viro <viro@zeniv.linux.org.uk>
+Cc: Jens Axboe <axboe@kernel.dk>
+Cc: Michael Kerrisk <mtk.manpages@gmail.com>
+Cc: Randy Dunlap <rdunlap@infradead.org>
+Cc: Josh Poimboeuf <jpoimboe@redhat.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Dong Jinguang <dongjinguang@huawei.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/pipe.c |   17 +++++++++++++++--
+ 1 file changed, 15 insertions(+), 2 deletions(-)
+
+--- a/fs/pipe.c
++++ b/fs/pipe.c
+@@ -1018,13 +1018,19 @@ const struct file_operations pipefifo_fo
+ 
+ /*
+  * Currently we rely on the pipe array holding a power-of-2 number
+- * of pages.
++ * of pages. Returns 0 on error.
+  */
+ static inline unsigned int round_pipe_size(unsigned int size)
+ {
+       unsigned long nr_pages;
+ 
++      if (size < pipe_min_size)
++              size = pipe_min_size;
++
+       nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
++      if (nr_pages == 0)
++              return 0;
++
+       return roundup_pow_of_two(nr_pages) << PAGE_SHIFT;
+ }
+ 
+@@ -1040,6 +1046,8 @@ static long pipe_set_size(struct pipe_in
+       long ret = 0;
+ 
+       size = round_pipe_size(arg);
++      if (size == 0)
++              return -EINVAL;
+       nr_pages = size >> PAGE_SHIFT;
+ 
+       if (!nr_pages)
+@@ -1123,13 +1131,18 @@ out_revert_acct:
+ int pipe_proc_fn(struct ctl_table *table, int write, void __user *buf,
+                size_t *lenp, loff_t *ppos)
+ {
++      unsigned int rounded_pipe_max_size;
+       int ret;
+ 
+       ret = proc_dointvec_minmax(table, write, buf, lenp, ppos);
+       if (ret < 0 || !write)
+               return ret;
+ 
+-      pipe_max_size = round_pipe_size(pipe_max_size);
++      rounded_pipe_max_size = round_pipe_size(pipe_max_size);
++      if (rounded_pipe_max_size == 0)
++              return -EINVAL;
++
++      pipe_max_size = rounded_pipe_max_size;
+       return ret;
+ }
+ 

diff --git a/queue-4.9/series b/queue-4.9/series
index c9ada2aae99265716e7274d1b904471bea1582b2..4ac70ed37baf474f4bfa8ffc46dbd3499ff30de9 100644 (file)
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -18,3 +18,4 @@ x86-cpufeature-move-processor-tracing-out-of-scattered-features.patch
 module-add-retpoline-tag-to-vermagic.patch
 x86-mm-pkeys-fix-fill_sig_info_pkey.patch
 x86-tsc-fix-erroneous-tsc-rate-on-skylake-xeon.patch
+pipe-avoid-round_pipe_size-nr_pages-overflow-on-32-bit.patch