| Message ID | 20230528164400.592092-1-princekumarmaurya06@gmail.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | Null check to prevent null-ptr-deref bug | expand |
On Sun, May 28, 2023 at 09:44:00AM -0700, Prince Kumar Maurya wrote: > sb_getblk(inode->i_sb, parent) return a null ptr and taking lock on that leads to the null-ptr-deref bug. > > Signed-off-by: Prince Kumar Maurya <princekumarmaurya06@gmail.com> > --- > fs/sysv/itree.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c > index b22764fe669c..3a6b66e719fd 100644 > --- a/fs/sysv/itree.c > +++ b/fs/sysv/itree.c > @@ -145,6 +145,8 @@ static int alloc_branch(struct inode *inode, > */ > parent = block_to_cpu(SYSV_SB(inode->i_sb), branch[n-1].key); > bh = sb_getblk(inode->i_sb, parent); > + if (!bh) > + break; > lock_buffer(bh); > memset(bh->b_data, 0, blocksize); > branch[n].bh = bh; > -- > 2.40.1 Why resend this when I already responded: https://lore.kernel.org/r/2023052803-pucker-depress-5452@gregkh confused, greg k-h
diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c index b22764fe669c..3a6b66e719fd 100644 --- a/fs/sysv/itree.c +++ b/fs/sysv/itree.c @@ -145,6 +145,8 @@ static int alloc_branch(struct inode *inode, */ parent = block_to_cpu(SYSV_SB(inode->i_sb), branch[n-1].key); bh = sb_getblk(inode->i_sb, parent); + if (!bh) + break; lock_buffer(bh); memset(bh->b_data, 0, blocksize); branch[n].bh = bh;
sb_getblk(inode->i_sb, parent) return a null ptr and taking lock on that leads to the null-ptr-deref bug. Signed-off-by: Prince Kumar Maurya <princekumarmaurya06@gmail.com> --- fs/sysv/itree.c | 2 ++ 1 file changed, 2 insertions(+)