From: Jeff Layton Date: Tue, 14 Nov 2017 19:42:57 +0000 (-0500) Subject: fcntl: don't cap l_start and l_end values for F_GETLK64 in compat syscall X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4d2dc2cc766c3b51929658cacbc6e34fc8e242fb;p=linux.git fcntl: don't cap l_start and l_end values for F_GETLK64 in compat syscall Currently, we're capping the values too low in the F_GETLK64 case. The fields in that structure are 64-bit values, so we shouldn't need to do any sort of fixup there. Make sure we check that assumption at build time in the future however by ensuring that the sizes we're copying will fit. With this, we no longer need COMPAT_LOFF_T_MAX either, so remove it. Fixes: 94073ad77fff2 (fs/locks: don't mess with the address limit in compat_fcntl64) Reported-by: Vitaly Lipatov Signed-off-by: Jeff Layton Reviewed-by: David Howells --- diff --git a/arch/arm64/include/asm/compat.h b/arch/arm64/include/asm/compat.h index e39d487bf7243..a3c7f271ad4c7 100644 --- a/arch/arm64/include/asm/compat.h +++ b/arch/arm64/include/asm/compat.h @@ -215,7 +215,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL /* * A pointer passed in from user mode. This should not diff --git a/arch/mips/include/asm/compat.h b/arch/mips/include/asm/compat.h index 8e2b5b5564886..49691331ada4c 100644 --- a/arch/mips/include/asm/compat.h +++ b/arch/mips/include/asm/compat.h @@ -200,7 +200,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL /* * A pointer passed in from user mode. This should not diff --git a/arch/parisc/include/asm/compat.h b/arch/parisc/include/asm/compat.h index 07f48827afdae..acf8aa07cbe09 100644 --- a/arch/parisc/include/asm/compat.h +++ b/arch/parisc/include/asm/compat.h @@ -195,7 +195,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL struct compat_ipc64_perm { compat_key_t key; diff --git a/arch/powerpc/include/asm/compat.h b/arch/powerpc/include/asm/compat.h index a035b1e5dfa7c..8a2aecfe9b024 100644 --- a/arch/powerpc/include/asm/compat.h +++ b/arch/powerpc/include/asm/compat.h @@ -185,7 +185,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL /* * A pointer passed in from user mode. This should not diff --git a/arch/s390/include/asm/compat.h b/arch/s390/include/asm/compat.h index 1b60eb3676d55..5e6a63641a5f1 100644 --- a/arch/s390/include/asm/compat.h +++ b/arch/s390/include/asm/compat.h @@ -263,7 +263,6 @@ typedef struct compat_siginfo { #define si_overrun _sifields._timer._overrun #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL /* * A pointer passed in from user mode. This should not diff --git a/arch/sparc/include/asm/compat.h b/arch/sparc/include/asm/compat.h index 977c3f280ba19..fa38c78de0f00 100644 --- a/arch/sparc/include/asm/compat.h +++ b/arch/sparc/include/asm/compat.h @@ -209,7 +209,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL /* * A pointer passed in from user mode. This should not diff --git a/arch/tile/include/asm/compat.h b/arch/tile/include/asm/compat.h index c14e36f008c8f..62a7b83025dd2 100644 --- a/arch/tile/include/asm/compat.h +++ b/arch/tile/include/asm/compat.h @@ -173,7 +173,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL struct compat_ipc64_perm { compat_key_t key; diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h index a600a6cda9ecd..2cbd75dd2fd35 100644 --- a/arch/x86/include/asm/compat.h +++ b/arch/x86/include/asm/compat.h @@ -210,7 +210,6 @@ typedef struct compat_siginfo { } compat_siginfo_t; #define COMPAT_OFF_T_MAX 0x7fffffff -#define COMPAT_LOFF_T_MAX 0x7fffffffffffffffL struct compat_ipc64_perm { compat_key_t key; diff --git a/fs/fcntl.c b/fs/fcntl.c index e15bcc4265d0e..0522e283a4f48 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -563,6 +563,9 @@ static int put_compat_flock64(const struct flock *kfl, struct compat_flock64 __u { struct compat_flock64 fl; + BUILD_BUG_ON(sizeof(kfl->l_start) > sizeof(ufl->l_start)); + BUILD_BUG_ON(sizeof(kfl->l_len) > sizeof(ufl->l_len)); + memset(&fl, 0, sizeof(struct compat_flock64)); copy_flock_fields(&fl, kfl); if (copy_to_user(ufl, &fl, sizeof(struct compat_flock64))) @@ -641,12 +644,8 @@ COMPAT_SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd, if (err) break; err = fcntl_getlk(f.file, convert_fcntl_cmd(cmd), &flock); - if (err) - break; - err = fixup_compat_flock(&flock); - if (err) - return err; - err = put_compat_flock64(&flock, compat_ptr(arg)); + if (!err) + err = put_compat_flock64(&flock, compat_ptr(arg)); break; case F_SETLK: case F_SETLKW: