Doug / smarc-fsl-linux-kernel

Download as
Browse Code ยป

Commit f6940fe9092e796119af691c7f722c252f4fc524

Authored by Jan Kara
Committed by Al Viro
1 parent 978d6d8c45
Exists in smarc-l5.0.0_1.0.0-ga and in 5 other branches 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

udf: Fix deadlock in udf_release_file() 

udf_release_file() can be called from munmap() path with mmap_sem held.  Thus
we cannot take i_mutex there because that ranks above mmap_sem. Luckily,
i_mutex is not needed in udf_release_file() anymore since protection by
i_data_sem is enough to protect from races with write and truncate.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Showing 1 changed file with 0 additions and 2 deletions Side-by-side Diff

... ... @@ -201,12 +201,10 @@
201 201 static int udf_release_file(struct inode *inode, struct file *filp)
202 202 {
203 203 if (filp->f_mode & FMODE_WRITE) {
204   - mutex_lock(&inode->i_mutex);
205 204 down_write(&UDF_I(inode)->i_data_sem);
206 205 udf_discard_prealloc(inode);
207 206 udf_truncate_tail_extent(inode);
208 207 up_write(&UDF_I(inode)->i_data_sem);
209   - mutex_unlock(&inode->i_mutex);
210 208 }
211 209 return 0;
212 210 }