Procfs does not set max file size (s_maxbytes) and ends up with default
value of
MAX_NON_LFS ((1UL<<31) - 1)
Commit be83bbf80682 ("mmap: introduce sane default mmap limits")
introduced "pgoff" limits checks for mmap, considering fs max file size
as upper limit, which made it impossible to mmap /proc/vmcore file
contents above 2Gb (/proc/vmcore appears to be the only procfs file
supporting mmap).
Reuse MAX_LFS_FILESIZE as procfs s_maxbytes value.
Fixes: be83bbf80682 ("mmap: introduce sane default mmap limits")
Signed-off-by: Vasily Gorbik <g...@linux.ibm.com>
---
fs/proc/inode.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 2cf3b74391ca..de1b3b1da883 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -502,6 +502,7 @@ int proc_fill_super(struct super_block *s, void *data, int
silent)
/* User space would break if executables or devices appear on proc */
s->s_iflags |= SB_I_USERNS_VISIBLE | SB_I_NOEXEC | SB_I_NODEV;
s->s_flags |= SB_NODIRATIME | SB_NOSUID | SB_NOEXEC;
+ s->s_maxbytes = MAX_LFS_FILESIZE;
s->s_blocksize = 1024;
s->s_blocksize_bits = 10;
s->s_magic = PROC_SUPER_MAGIC;
--
⢀⡵⣤⡴⣅ 2.17.0
⠏⢟⡛⣛⠏⠇ space invaders edition
