From f38aed975c0c3645bbdfc5ebe35726e64caaf588 Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Mon, 27 Oct 2014 00:46:11 +0100 Subject: [PATCH] UBI: Fix invalid vfree() The logic of vfree()'ing vol->upd_buf is tied to vol->updating. In ubi_start_update() vol->updating is set long before vmalloc()'ing vol->upd_buf. If we encounter a write failure in ubi_start_update() before vmalloc() the UBI device release function will try to vfree() vol->upd_buf because vol->updating is set. Fix this by allocating vol->upd_buf directly after setting vol->updating. Fixes: [ 31.559338] UBI warning: vol_cdev_release: update of volume 2 not finished, volume is damaged [ 31.559340] ------------[ cut here ]------------ [ 31.559343] WARNING: CPU: 1 PID: 2747 at mm/vmalloc.c:1446 __vunmap+0xe3/0x110() [ 31.559344] Trying to vfree() nonexistent vm area (ffffc90001f2b000) [ 31.559345] Modules linked in: [ 31.565620] 0000000000000bba ffff88002a0cbdb0 ffffffff818f0497 ffff88003b9ba148 [ 31.566347] ffff88002a0cbde0 ffffffff8156f515 ffff88003b9ba148 0000000000000bba [ 31.567073] 0000000000000000 0000000000000000 ffff88002a0cbe88 ffffffff8156c10a [ 31.567793] Call Trace: [ 31.568034] [] dump_stack+0x4e/0x7a [ 31.568510] [] ubi_io_write_vid_hdr+0x155/0x160 [ 31.569084] [] ubi_eba_write_leb+0x23a/0x870 [ 31.569628] [] vol_cdev_write+0x226/0x380 [ 31.570155] [] vfs_write+0xb5/0x1f0 [ 31.570627] [] SyS_pwrite64+0x6a/0xa0 [ 31.571123] [] system_call_fastpath+0x16/0x1b Cc: Signed-off-by: Richard Weinberger Signed-off-by: Artem Bityutskiy --- drivers/mtd/ubi/upd.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/mtd/ubi/upd.c b/drivers/mtd/ubi/upd.c index ec2c2dc1c1ca..2a1b6e037e1a 100644 --- a/drivers/mtd/ubi/upd.c +++ b/drivers/mtd/ubi/upd.c @@ -133,6 +133,10 @@ int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol, ubi_assert(!vol->updating && !vol->changing_leb); vol->updating = 1; + vol->upd_buf = vmalloc(ubi->leb_size); + if (!vol->upd_buf) + return -ENOMEM; + err = set_update_marker(ubi, vol); if (err) return err; @@ -152,14 +156,12 @@ int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol, err = clear_update_marker(ubi, vol, 0); if (err) return err; + + vfree(vol->upd_buf); vol->updating = 0; return 0; } - vol->upd_buf = vmalloc(ubi->leb_size); - if (!vol->upd_buf) - return -ENOMEM; - vol->upd_ebs = div_u64(bytes + vol->usable_leb_size - 1, vol->usable_leb_size); vol->upd_bytes = bytes; -- GitLab