[PATCH 5.1 017/155] initramfs: free initrd memory if opening /initrd.image fails

Greg Kroah-Hartman
2019-06-13T16:06:47Z

[ Upstream commit 54c7a8916a887f357088f99e9c3a7720cd57d2c8 ]

Patch series "initramfs tidyups".

I've spent some time chasing down behavior in initramfs and found
plenty of opportunity to improve the code. A first stab on that is
contained in this series.

This patch (of 7):

We free the initrd memory for all successful or error cases except for the
case where opening /initrd.image fails, which looks like an oversight.

Steven said:

: This also changes the behaviour when CONFIG_INITRAMFS_FORCE is enabled
: - specifically it means that the initrd is freed (previously it was
: ignored and never freed). But that seems like reasonable behaviour and
: the previous behaviour looks like another oversight.

Link: http://lkml.kernel.org/r/20190213174621.29297-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Cc: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
init/initramfs.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/init/initramfs.c b/init/initramfs.c
index 4749e1115eef..c322e1099f43 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -612,13 +612,12 @@ static int __init populate_rootfs(void)
printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
err = unpack_to_rootfs((char *)initrd_start,
initrd_end - initrd_start);
- if (!err) {
- free_initrd();
+ if (!err)
goto done;
- } else {
- clean_rootfs();
- unpack_to_rootfs(__initramfs_start, __initramfs_size);
- }
+
+ clean_rootfs();
+ unpack_to_rootfs(__initramfs_start, __initramfs_size);
+
printk(KERN_INFO "rootfs image is not initramfs (%s)"
"; looks like an initrd\n", err);
fd = ksys_open("/initrd.image",
@@ -632,7 +631,6 @@ static int __init populate_rootfs(void)
written, initrd_end - initrd_start);

ksys_close(fd);
- free_initrd();
}
done:
/* empty statement */;
@@ -642,9 +640,9 @@ static int __init populate_rootfs(void)
initrd_end - initrd_start);
if (err)
printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
- free_initrd();
#endif
}
+ free_initrd();
flush_delayed_fput();
return 0;
}
--
2.20.1