Doug / smarc-fsl-linux-kernel

Download as
Browse Code ยป

Commit 225add619624b4877941470f31d297e0151b21be

Authored by Eric Sandeen
Committed by Linus Torvalds
1 parent ce2c6b5384
Exists in master and in 7 other branches imx_3.0.35_4.1.0, imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga, smarc-l5.0.0_1.0.0-ga

[PATCH] udf: initialize parts of inode earlier in create 

I saw an oops down this path when trying to create a new file on a UDF
filesystem which was internally marked as readonly, but mounted rw:

udf_create
        udf_new_inode
                new_inode
                        alloc_inode
                        	udf_alloc_inode
                udf_new_block
                        returns EIO due to readonlyness
                iput (on error)
                        udf_put_inode
                                udf_discard_prealloc
                                        udf_next_aext
                                                udf_current_aext
                                                        udf_get_fileshortad
                                                                OOPS

the udf_discard_prealloc() path was examining uninitialized fields of the
udf inode.

udf_discard_prealloc() already has this code to short-circuit the discard
path if no extents are preallocated:

        if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
                inode->i_size == UDF_I_LENEXTENTS(inode))
        {
                return;
        }

so if we initialize UDF_I_LENEXTENTS(inode) = 0 earlier in udf_new_inode,
we won't try to free the (not) preallocated blocks, since this will match
the i_size = 0 set when the inode was initialized.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Showing 1 changed file with 6 additions and 5 deletions Side-by-side Diff

... ... @@ -75,6 +75,12 @@
75 75 }
76 76 *err = -ENOSPC;
77 77  
  78 + UDF_I_UNIQUE(inode) = 0;
  79 + UDF_I_LENEXTENTS(inode) = 0;
  80 + UDF_I_NEXT_ALLOC_BLOCK(inode) = 0;
  81 + UDF_I_NEXT_ALLOC_GOAL(inode) = 0;
  82 + UDF_I_STRAT4096(inode) = 0;
  83 +
78 84 block = udf_new_block(dir->i_sb, NULL, UDF_I_LOCATION(dir).partitionReferenceNum,
79 85 start, err);
80 86 if (*err)
... ... @@ -84,11 +90,6 @@
84 90 }
85 91  
86 92 mutex_lock(&sbi->s_alloc_mutex);
87   - UDF_I_UNIQUE(inode) = 0;
88   - UDF_I_LENEXTENTS(inode) = 0;
89   - UDF_I_NEXT_ALLOC_BLOCK(inode) = 0;
90   - UDF_I_NEXT_ALLOC_GOAL(inode) = 0;
91   - UDF_I_STRAT4096(inode) = 0;
92 93 if (UDF_SB_LVIDBH(sb))
93 94 {
94 95 struct logicalVolHeaderDesc *lvhd;